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Sample records for associating water-soluble copolymers

  1. Thermodynamic interactions of water-soluble homopolymers and double-hydrophilic diblock copolymer

    International Nuclear Information System (INIS)

    Yazici, D. Topaloglu; Askin, A.; Buetuen, V.

    2008-01-01

    Thermodynamic interaction parameters of water-soluble poly[2-(dimethylamino)ethyl methacrylate] (DMA) and poly[2-(N-morpholino)ethyl methacrylate] (MEMA) homopolymers and their diblock copolymer (DMA-MEMA) were investigated at the temperatures above their glass-transition temperatures (T g ) by inverse gas chromatography (IGC) method. Sorption thermodynamic parameters of some aliphatic, alicyclic and aromatic hydrocarbons, weight fraction activity coefficients, Flory-Huggins interaction parameters, and solubility parameters for hydrocarbons and polymers were calculated. It was observed that sorption thermodynamic parameters on (co)polymers depend on the molecular structures of hydrocarbons. Evaluating both the calculated values of the weight fraction activity coefficients and Flory-Huggins interaction parameters, the solving ability of the hydrocarbons for DMA, MEMA homopolymers, and DMA-MEMA diblock copolymer decreased in the following sequence: Aromatic > alicyclic > aliphatic hydrocarbons

  2. Monoglyceride-based self-assembling copolymers as carriers for poorly water-soluble drugs.

    Science.gov (United States)

    Rouxhet, L; Dinguizli, M; Latere Dwan'isa, J P; Ould-Ouali, L; Twaddle, P; Nathan, A; Brewster, M E; Rosenblatt, J; Ariën, A; Préat, V

    2009-12-01

    To develop self-assembling polymers forming polymeric micelles and increasing the solubility of poorly soluble drugs, amphiphilic polymers containing a hydrophilic PEG moiety and a hydrophobic moiety derived from monoglycerides and polyethers were designed. The biodegradable copolymers were obtained via a polycondensation reaction of polyethylene glycol (PEG), monooleylglyceride (MOG) and succinic anhydride (SA). Polymers with molecular weight below 10,000 g/mol containing a minimum of 40 mol% PEG and a maximum of 10 mol% MOG self-assembled spontaneously in aqueous media upon gentle mixing. They formed particles with a diameter of 10 nm although some aggregation was evident. The critical micellar concentration varied between 3x10(-4) and 4x10(-3) g/ml, depending on the polymer. The cloud point (> or = 66 degrees C) and flocculation point (> or = 0.89 M) increased with the PEG chain length. At a 1% concentration, the polymers increased the solubility of poorly water-soluble drug candidates up to 500-fold. Drug solubility increased as a function of the polymer concentration. HPMC capsules filled with these polymers disintegrated and released model drugs rapidly. Polymer with long PEG chains had a lower cytotoxicity (MTT test) on Caco-2 cells. All of these data suggest that the object polymers, in particular PEG1000/MOG/SA (45/5/50) might be potential candidates for improving the oral biopharmaceutical performance of poorly soluble drugs.

  3. Radiation synthesis of the water-soluble, temperature sensitive polymer, copolymer and study on their properties

    International Nuclear Information System (INIS)

    Zhai Maolin; Yin Min; Ha Hongfei

    1994-01-01

    In order to obtain the water-soluble, temperature sensitive polymer and activated copolymer, the radiation polymerization of N-isopropylacrylamide (NIPAAm), radiation copolymerization of NIPAAm and N-acryloxysuccide (NASI) in aqueous solution or in buffer solution (PBS pH = 7.4) have been carried out by γ-rays from 60 Co source at room temperature. The optimum dose range (1-7 kGy), dose rate (>40 Gy/min) and monomer concentration (1%) were chosen through determining the monomer conversion yield and molecular weight (M w = 6.8 x 10 5 ) of product. Synthesis of the reversible linear polymer was performed in tetrahydrofuran (THF) as well. In this way a white powder product could be obtained which possesses of thermally reversible property too, when it was dissolved in water or PBS. The only disadvantages of this method is that the molecular weight of the polymer produced in THF was much lower than that in aqueous solution

  4. Radiation synthesis of a water-soluble temperature sensitive polymer, activated copolymer and applications in immobilization of proteins

    International Nuclear Information System (INIS)

    Zhai Maolin; Ha Hongfei; Wu Jilan

    1993-01-01

    In this work the radiation polymerization of N-isopropylacrylamide (NIPAAM) in aqueous solutions has been carried out and a water-soluble, temperature sensitive polymer and copolymer were obtained by using γ-rays from Co-60 source at room temperature. We have gained the optimum dose and dose-rate of radiation synthesis of linear polyNIPAAM through determining conversion yield and viscosity. In order to immobilize protein (BSA) and enzyme (HRP) into this water-soluble polymer, we prepared an activated copolymer, poly(N-isopropylacrylamide-co-N-acryloxysuccinimide). The BSA and HRP has been immobilized onto the activated copolymer. The BSA (HRP)/copolymer conjugates still kept the original thermally sensitive properties of the linear polyNIPAAM. The conjugation yield of BSA to the activated copolymer decreased with increasing dose. Immobilized HRP was stable at 0 o C for a long time and has, at least, 4 days stability at room temperature. Immobilized HRP activity was lowered when the temperature was raised. This phenomenon was reversible and the immobilized HRP regained activity. The optimum pH of the immobilized HRP shifted from ca.5 upward to ca. 7. (author)

  5. Synthesis and characterization of a novel water-soluble cationic diblock copolymer with star conformation by ATRP

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shuzhao [Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3 (Canada); School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237 (China); Xiao, Miaomiao [Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3 (Canada); Zheng, Anna [School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237 (China); Xiao, Huining, E-mail: hxiao@unb.ca [Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3 (Canada)

    2014-10-01

    A water-soluble cationic diblock copolymer, CD-PAM-b-PMeDMA, was synthesized through atom transfer radical polymerization (ATRP) from a β-cyclodextrin (CD) macroinitiator with 10-active sites (10Br-β-CD). In order to reduce the cytotoxicity of the CD-PAM-b-PMeDMA, biocompatible polyacrylamide (PAM) was first introduced onto the surface of β-CD as a scaffold structure by ATRP using the 10Br-β-CD as a macroinitiator. The reaction conditions of AM were explored and optimized. The ATRP of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride (MeDMA) was also performed to synthesize the second cationic block using the resulting CD-PAM as a macroinitiator. The resulting diblock copolymer shows an increased hydrodynamic radius in aqueous solution with a pretty low concentration compared with β-CD. In addition, it appears a near-uniform coniform after being deposited on mica ascribed to the presence of an asymmetric 10-arm structure. - Highlights: • A 10-arm diblock polymer was prepared by ATRP for the potential use as a non-viral gene delivery. • PAM was first synthesized in a controlled manner considering its biocompatibility. • The hydrodynamic radius of the copolymer in aqueous solution increase to 130 nm from 7.5 nm of CD. • The copolymer appears coniform after deposited on mica surface due to the charge attraction.

  6. Solvent-Free Polymerization of L-Aspartic Acid in the Presence of D-Sorbitol to Obtain Water Soluble or Network Copolymers

    Science.gov (United States)

    L-aspartic acid was thermally polymerized in the presence of D-sorbitol with the goal of synthesizing new, higher molecular weight water soluble and absorbent copolymers. No reaction occurred when aspartic acid alone was heated at 170 or 200 degrees C. In contrast, heating sorbitol and aspartic ac...

  7. An Electrochemical Study of Two Self-Dopable Water-Soluble Aniline Derivatives: Electrochemical Deposition of Copolymers

    Directory of Open Access Journals (Sweden)

    Loredana Vacareanu

    2012-01-01

    Full Text Available An electrochemical study of two water-soluble aniline derivatives, N-(3-sulfopropyl aniline (AnPS and N-(3-sulfopropyl p-aminodiphenylamine (DAnPS, in aqueous acidic electrolytic solutions containing different kinds of doping anions (Cl −, SO4 2−, and ClO4 − was carried out. At sufficiently high anodic potential, the sulfonated aniline derivatives undergo oxidation processes yielding cation-radical and dimer intermediates, but no polymer deposition was observed on the working electrode surface. Experimental results showed that both aniline derivatives are electroactive compounds exhibiting redox behaviour in the range of potential of −0.2 V–1.6 V. Due to the self-doping effect induced by sulfonic groups, AnPS and DAnPS compounds have good electroactivity even in neat water solution. By adding a small amount of aniline into electrolytic system, thin layers of copolymers were deposited on the working electrode surface. The copolymer layers formed on the electrodes show a highly orientational and positional order, confirmed by AFM and XRD spectroscopic techniques. During the anodic oxidation processes some distinct colour changes were observed.

  8. Thermodynamics of association of water soluble fullerene derivatives

    Indian Academy of Sciences (India)

    SONANKI KESHRI

    2017-08-31

    Aug 31, 2017 ... Entropic and enthalpic contributions to the association of solute molecules are calculated ... authors.7,46–70 The association of fullerene in aque- ous media is ..... The main mechanism accounting for the stabiliza- tion of the ...

  9. Preparation of Water-soluble Polyion Complex (PIC Micelles Covered with Amphoteric Random Copolymer Shells with Pendant Sulfonate and Quaternary Amino Groups

    Directory of Open Access Journals (Sweden)

    Rina Nakahata

    2018-02-01

    Full Text Available An amphoteric random copolymer (P(SA91 composed of anionic sodium 2-acrylamido-2-methylpropanesulfonate (AMPS, S and cationic 3-acrylamidopropyl trimethylammonium chloride (APTAC, A was prepared via reversible addition-fragmentation chain transfer (RAFT radical polymerization. The subscripts in the abbreviations indicate the degree of polymerization (DP. Furthermore, AMPS and APTAC were polymerized using a P(SA91 macro-chain transfer agent to prepare an anionic diblock copolymer (P(SA91S67 and a cationic diblock copolymer (P(SA91A88, respectively. The DP was estimated from quantitative 13C NMR measurements. A stoichiometrically charge neutralized mixture of the aqueous P(SA91S67 and P(SA91A88 formed water-soluble polyion complex (PIC micelles comprising PIC cores and amphoteric random copolymer shells. The PIC micelles were in a dynamic equilibrium state between PIC micelles and charge neutralized small aggregates composed of a P(SA91S67/P(SA91A88 pair. Interactions between PIC micelles and fetal bovine serum (FBS in phosphate buffered saline (PBS were evaluated by changing the hydrodynamic radius (Rh and light scattering intensity (LSI. Increases in Rh and LSI were not observed for the mixture of PIC micelles and FBS in PBS for one day. This observation suggests that there is no interaction between PIC micelles and proteins, because the PIC micelle surfaces were covered with amphoteric random copolymer shells. However, with increasing time, the diblock copolymer chains that were dissociated from PIC micelles interacted with proteins.

  10. Genome-Wide Association of Stem Water Soluble Carbohydrates in Bread Wheat.

    Science.gov (United States)

    Dong, Yan; Liu, Jindong; Zhang, Yan; Geng, Hongwei; Rasheed, Awais; Xiao, Yonggui; Cao, Shuanghe; Fu, Luping; Yan, Jun; Wen, Weie; Zhang, Yong; Jing, Ruilian; Xia, Xianchun; He, Zhonghu

    2016-01-01

    Water soluble carbohydrates (WSC) in stems play an important role in buffering grain yield in wheat against biotic and abiotic stresses; however, knowledge of genes controlling WSC is very limited. We conducted a genome-wide association study (GWAS) using a high-density 90K SNP array to better understand the genetic basis underlying WSC, and to explore marker-based breeding approaches. WSC was evaluated in an association panel comprising 166 Chinese bread wheat cultivars planted in four environments. Fifty two marker-trait associations (MTAs) distributed across 23 loci were identified for phenotypic best linear unbiased estimates (BLUEs), and 11 MTAs were identified in two or more environments. Liner regression showed a clear dependence of WSC BLUE scores on numbers of favorable (increasing WSC content) and unfavorable alleles (decreasing WSC), indicating that genotypes with higher numbers of favorable or lower numbers of unfavorable alleles had higher WSC content. In silico analysis of flanking sequences of trait-associated SNPs revealed eight candidate genes related to WSC content grouped into two categories based on the type of encoding proteins, namely, defense response proteins and proteins triggered by environmental stresses. The identified SNPs and candidate genes related to WSC provide opportunities for breeding higher WSC wheat cultivars.

  11. Genome-Wide Association of Stem Water Soluble Carbohydrates in Bread Wheat.

    Directory of Open Access Journals (Sweden)

    Yan Dong

    Full Text Available Water soluble carbohydrates (WSC in stems play an important role in buffering grain yield in wheat against biotic and abiotic stresses; however, knowledge of genes controlling WSC is very limited. We conducted a genome-wide association study (GWAS using a high-density 90K SNP array to better understand the genetic basis underlying WSC, and to explore marker-based breeding approaches. WSC was evaluated in an association panel comprising 166 Chinese bread wheat cultivars planted in four environments. Fifty two marker-trait associations (MTAs distributed across 23 loci were identified for phenotypic best linear unbiased estimates (BLUEs, and 11 MTAs were identified in two or more environments. Liner regression showed a clear dependence of WSC BLUE scores on numbers of favorable (increasing WSC content and unfavorable alleles (decreasing WSC, indicating that genotypes with higher numbers of favorable or lower numbers of unfavorable alleles had higher WSC content. In silico analysis of flanking sequences of trait-associated SNPs revealed eight candidate genes related to WSC content grouped into two categories based on the type of encoding proteins, namely, defense response proteins and proteins triggered by environmental stresses. The identified SNPs and candidate genes related to WSC provide opportunities for breeding higher WSC wheat cultivars.

  12. RAFT Aqueous Dispersion Polymerization of N-(2-(Methacryloyloxy)ethyl)pyrrolidone: A Convenient Low Viscosity Route to High Molecular Weight Water-Soluble Copolymers.

    Science.gov (United States)

    Cunningham, Victoria J; Derry, Matthew J; Fielding, Lee A; Musa, Osama M; Armes, Steven P

    2016-06-28

    RAFT solution polymerization of N -(2-(methacryoyloxy)ethyl)pyrrolidone (NMEP) in ethanol at 70 °C was conducted to produce a series of PNMEP homopolymers with mean degrees of polymerization (DP) varying from 31 to 467. Turbidimetry was used to assess their inverse temperature solubility behavior in dilute aqueous solution, with an LCST of approximately 55 °C being observed in the high molecular weight limit. Then a poly(glycerol monomethacylate) (PGMA) macro-CTA with a mean DP of 63 was chain-extended with NMEP using a RAFT aqueous dispersion polymerization formulation at 70 °C. The target PNMEP DP was systematically varied from 100 up to 6000 to generate a series of PGMA 63 -PNMEP x diblock copolymers. High conversions (≥92%) could be achieved when targeting up to x = 5000. GPC analysis confirmed high blocking efficiencies and a linear evolution in M n with increasing PNMEP DP. A gradual increase in M w / M n was also observed when targeting higher DPs. However, this problem could be minimized ( M w / M n RAFT aqueous dispersion polymerization of NMEP was approximately four times faster than the RAFT solution polymerization of NMEP in ethanol when targeting the same DP in each case. This is perhaps surprising because both 1 H NMR and SAXS studies indicate that the core-forming PNMEP chains remain relatively solvated at 70 °C in the latter formulation. Moreover, dissolution of the initial PGMA 63 -PNMEP x particles occurs on cooling from 70 to 20 °C as the PNMEP block passes through its LCST. Hence this RAFT aqueous dispersion polymerization formulation offers an efficient route to a high molecular weight water-soluble polymer in a rather convenient low-viscosity form. Finally, the relatively expensive PGMA macro-CTA was replaced with a poly(methacrylic acid) (PMAA) macro-CTA. High conversions were also achieved for PMAA 85 -PNMEP x diblock copolymers prepared via RAFT aqueous dispersion polymerization for x ≤ 4000. Again, better control was achieved when

  13. Water Soluble Polymers for Pharmaceutical Applications

    Directory of Open Access Journals (Sweden)

    Veeran Gowda Kadajji

    2011-11-01

    Full Text Available Advances in polymer science have led to the development of novel drug delivery systems. Some polymers are obtained from natural resources and then chemically modified for various applications, while others are chemically synthesized and used. A large number of natural and synthetic polymers are available. In the present paper, only water soluble polymers are described. They have been explained in two categories (1 synthetic and (2 natural. Drug polymer conjugates, block copolymers, hydrogels and other water soluble drug polymer complexes have also been explained. The general properties and applications of different water soluble polymers in the formulation of different dosage forms, novel delivery systems and biomedical applications will be discussed.

  14. Functional single-wall carbon nanotube nanohybrids--associating SWNTs with water-soluble enzyme model systems.

    Science.gov (United States)

    Guldi, Dirk M; Rahman, G M Aminur; Jux, Norbert; Balbinot, Domenico; Hartnagel, Uwe; Tagmatarchis, Nikos; Prato, Maurizio

    2005-07-13

    We succeeded in integrating single-wall carbon nanotubes (SWNTs), several water-soluble pyrene derivatives (pyrene(-)), which bear negatively charged ionic headgroups, and a series of water-soluble metalloporphyrins (MP(8+)) into functional nanohybrids through a combination of associative van der Waals and electrostatic interactions. The resulting SWNT/pyrene(-) and SWNT/pyrene(-)/MP(8+) were characterized by spectroscopic and microscopic means and were found to form stable nanohybrid structures in aqueous media. A crucial feature of our SWNT/pyrene(-) and SWNT/pyrene(-)/MP(8)(+) is that an efficient exfoliation of the initial bundles brings about isolated nanohybrid structures. When the nanohybrid systems are photoexcited with visible light, a rapid intrahybrid charge separation causes the reduction of the electron-accepting SWNT and, simultaneously, the oxidation of the electron-donating MP(8)(+). Transient absorption measurements confirm that the radical ion pairs are long-lived, with lifetimes in the microsecond range. Particularly beneficial are charge recombination dynamics that are located deep in the Marcus-inverted region. We include, for the first time, work devoted to exploring and testing FeP(8)(+) and CoP(8)(+) in donor-acceptor nanohybrids.

  15. Biochemical synthesis of water soluble conducting polymers

    Science.gov (United States)

    Bruno, Ferdinando F.; Bernabei, Manuele

    2016-05-01

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  16. Biochemical synthesis of water soluble conducting polymers

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Ferdinando F., E-mail: Ferdinando-Bruno@uml.edu [US Army Natick Soldier Research, Development and Engineering Center, Natick, MA 01760 (United States); Bernabei, Manuele [ITAF, Test Flight Centre, Chemistry Dept. Pratica di Mare AFB, 00071 Pomezia (Rome), Italy (UE) (Italy)

    2016-05-18

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  17. Biochemical synthesis of water soluble conducting polymers

    International Nuclear Information System (INIS)

    Bruno, Ferdinando F.; Bernabei, Manuele

    2016-01-01

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  18. Preparation of Water-Soluble Homo and Copolymers of Bithiophene with 3,4-Ethylene Dioxythiophene and 3-Dodecylthiophene in Presence of Polystyrene Sulfonic Acid: Structure, Morphology, Thermal Stability

    Directory of Open Access Journals (Sweden)

    Bakhshali Massoumi

    2015-04-01

    Full Text Available Conductive polymers based on water-soluble polythiophenes were prepared. In this respect, alkylation reaction was carried out to synthesize the monomer 3-dodecylthiophene using 3-bromothiophene, bromododecane and magnesium. The monomer 2,2′-bithiophene was also prepared from 2-bromothiophene. Then, poly(2,2′-bithiophene, poly(3,4-ethylenedioxythiophene and poly(3-dodecylthiophene homopolymers were prepared at room temperature by successive chemical oxidation in the presence of polystyrene sulfonic acid and ammonium persulfate and water, as dopant, oxidant and solvent, respectively, under vigorous stirring. Under similar conditions, 2,2′-bithiophene copolymers with 3-dodecylthiophene and 3,4-ethylenedioxythiophene, copolymers with 3-dodecylthiophene were prepared at different molar ratios. To purify and dry the prepared polymers, dialysis tubs and freezing dry processes were applied. Structure of homo and copolymers were investigated by Fourier transform infrared (FTIR. Conjugated and planar structures of polymers were studied by Ultravoilet (UV-vis spectroscopy. The electrical conductivity of synthesized polymers was measured by four probe technique. The morphology and thermal stability of the products were studied using scanning electron microscopy (SEM, transmission electron microscopy (TEM and thermogravimetric analysis (TGA. Finally, solubility of homo and copolymers were tested in some organic solvents and water. Electro- activity of the prepared polymers was studied by cyclic voltammetry (CV on the glassy carbon (GC in LiClO4/CH3CN electrolyte solution and their electro-activity was confirmed. Electro-conductivity and electro-activity of homo and co polymers were low due topresence of polystyrene sulfonic acid which reduced the immobility of the polymers.

  19. Metal-ion retention properties of water-soluble amphiphilic block copolymer in double emulsion systems (w/o/w) stabilized by non-ionic surfactants.

    Science.gov (United States)

    Palencia, Manuel; Rivas, Bernabé L

    2011-11-15

    Metal-ion retention properties of water-soluble amphiphilic polymers in presence of double emulsion were studied by diafiltration. Double emulsion systems, water-in-oil-in-water, with a pH gradient between external and internal aqueous phases were prepared. A poly(styrene-co-maleic anhydride) (PSAM) solution at pH 6.0 was added to the external aqueous phase of double emulsion and by application of pressure a divalent metal-ion stream was continuously added. Metal-ions used were Cu(2+) and Cd(2+) at the same pH of polymer solution. According to our results, metal-ion retention is mainly the result of polymer-metal interaction. Interaction between PSMA and reverse emulsion globules is strongly controlled by amount of metal-ions added in the external aqueous phase. In addition, as metal-ion concentration was increased, a negative effect on polymer retention capacity and promotion of flocculation phenomena were produced. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Water Soluble Polymers for Pharmaceutical Applications

    OpenAIRE

    Veeran Gowda Kadajji; Guru V. Betageri

    2011-01-01

    Advances in polymer science have led to the development of novel drug delivery systems. Some polymers are obtained from natural resources and then chemically modified for various applications, while others are chemically synthesized and used. A large number of natural and synthetic polymers are available. In the present paper, only water soluble polymers are described. They have been explained in two categories (1) synthetic and (2) natural. Drug polymer conjugates, block copolymers, hydrogel...

  1. Microflow Mechanism of Oil Displacement by Viscoelastic Hydrophobically Associating Water-Soluble Polymers in Enhanced Oil Recovery

    Directory of Open Access Journals (Sweden)

    Huiying Zhong

    2018-06-01

    Full Text Available Polymer flooding plays an important role in enhanced oil recovery (EOR, particularly in China, where partially hydrolyzed polyacrylamide (HPAM and hydrophobically associating water-soluble polymers (HAWP are used in onshore and offshore reservoirs, respectively. Many researchers have highlighted the elasticity of HPAM, which can be used to improve the sweep efficiency, i.e., the ratio of the area swept by an injected fluid to the oil area. On the other hand, fewer studies exist on the elasticity of HAWP. In this study, we investigate the flow of HAWP and Xanthan solutions with identical viscosities in core experiments in terms of elasticity; results reveal that the HAWP can produce shear thickening in the core. The constitutive equation for the HAWP can be obtained using the simulation results matched with the experimental data. On the basis of these experiments, we established a two-phase flow model of a polymer and oil, including the continuity, momentum, constitutive, and phase equations. The volume-of-fluid (VOF method was used to track the interface between the two phases. A complex pore model was established based on the glass-etched model used in the experiment. We used the OpenFOAM platform to solve the mathematical model. The saturation, pressure, and stress tensor distributions were obtained. The results show that the displacement efficiency increased as the elasticity of the polymer increased; accordingly, the elasticity can enlarge the sweep area and decrease the residual oil saturation. As the elasticity increases, the stresses (the first normal stress, second normal stress, and shear stress increase. Finally, the results obtained in this study can be used as a guideline in polymer design, screening, and optimization in the polymer flooding oilfields.

  2. Water-soluble Organic Components in Aerosols Associated with Savanna Fires in Southern Africa: Identification, Evolution and Distribution

    Science.gov (United States)

    Gao, Song; Hegg, Dean A.; Hobbs, Peter V.; Kirchstetter, Thomas W.; Magi, Brian I.; Sadilek, Martin

    2003-01-01

    During the SAFARI 2000 field campaign, both smoke aerosols from savanna fires and haze aerosols in the boundary layer and in the free troposphere were collected from an aircraft in southern Africa. These aerosol samples were analyzed for their water-soluble chemical components, particularly the organic species. A novel technique, electrospray ionization-ion trap mass spectrometry, was used concurrently with an ion chromatography system to analyze for carbohydrate species. Seven carbohydrates, seven organic acids, five metallic elements, and three inorganic anions were identified and quantified. On the average, these 22 species comprised 36% and 27% of the total aerosol mass in haze and smoke aerosols, respectively. For the smoke aerosols, levoglucosan was the most abundant carbohydrate species, while gluconic acid was tentatively identified as the most abundant organic acid. The mass abundance and possible source of each class of identified species are discussed, along with their possible formation pathways. The combustion phase of a fire had an impact on the chemical composition of the emitted aerosols. Secondary formation of sulfate, nitrate, levoglucosan, and several organic acids occurred during the initial aging of smoke aerosols. It is likely that under certain conditions, some carbohydrate species in smoke aerosols, such as levoglucosan, were converted to organic acids during upward transport.

  3. Novel micellar systems for the formulation of poorly water soluble drugs : biocompatibility aspects and pharmaceutical applications

    OpenAIRE

    Dumontet Mondon, Karine

    2010-01-01

    Amongst the large number of novel drugs, 95% are lipophilic and poorly water soluble. Particularly, this renders their aqueous formulation very difficult. In this regard this thesis focused on polymeric micelles based on novel MPEG-hexPLA copolymers forming a hydrophilic shell and a very hydrophobic core that favors the incorporation of poorly water soluble drugs. Although the drug hydrophobicity and water solubility are the main parameters in respect to their incorporation efficiency, struct...

  4. Water-soluble vitamins.

    Science.gov (United States)

    Konings, Erik J M

    2006-01-01

    Simultaneous Determination of Vitamins.--Klejdus et al. described a simultaneous determination of 10 water- and 10 fat-soluble vitamins in pharmaceutical preparations by liquid chromatography-diode-array detection (LC-DAD). A combined isocratic and linear gradient allowed separation of vitamins in 3 distinct groups: polar, low-polar, and nonpolar. The method was applied to pharmaceutical preparations, fortified powdered drinks, and food samples, for which results were in good agreement with values claimed. Heudi et al. described a separation of 9 water-soluble vitamins by LC-UV. The method was applied for the quantification of vitamins in polyvitaminated premixes used for the fortification of infant nutrition products. The repeatability of the method was evaluated at different concentration levels and coefficients of variation were based on, for example, LC. Koontz et al. showed results of total folate concentrations measured by microbiological assay in a variety of foods. Samples were submitted in a routine manner to experienced laboratories that regularly perform folate analysis fee-for-service basis in the United States. Each laboratory reported the use of a microbiological method similar to the AOAC Official Method for the determination of folic acid. Striking was, the use of 3 different pH extraction conditions by 4 laboratories. Only one laboratory reported using a tri-enzyme extraction. Results were evaluated. Results for folic acid fortified foods had considerably lower between-laboratory variation, 9-11%, versus >45% for other foods. Mean total folate ranged from 14 to 279 microg/100 g for a mixed vegetable reference material, from 5 to 70 microg/100 g for strawberries, and from 28 to 81 microg/100 g for wholemeal flour. One should realize a large variation in results, which might be caused by slight modifications in the microbiological analysis of total folate in foods or the analysis in various (unfortified) food matrixes. Furthermore, optimal

  5. Rheological Properties of Hydrophobically Associative Copolymers Prepared in a Mixed Micellar Method Based on Methacryloxyethyl-dimethyl Cetyl Ammonium Chloride as Surfmer

    Directory of Open Access Journals (Sweden)

    Rui Liu

    2014-01-01

    Full Text Available A novel cationic surfmer, methacryloxyethyl-dimethyl cetyl ammonium chloride (DMDCC, is synthesized. The micellar properties, including critical micelle concentration and aggregation number, of DMDCC-SDS mixed micelle system are studied using conductivity measurement and a steady-state fluorescence technique. A series of water-soluble associative copolymers with acrylamide and DMDCC are prepared using the mixed micellar polymerization. Compared to conventional micellar polymerization, this new method could not only reasonably adjust the length of the hydrophobic microblock, that is, NH, but also sharply reduce the amount of surfactant. Their rheological properties related to hydrophobic microblock and stickers are studied by the combination of steady flow and linear viscoelasticity experiments. The results indicate that both the hydrophobic content and, especially the length of the hydrophobic microblock are the dominating factors effecting the intermolecular hydrophobic association. The presence of salt influences the dynamics of copolymers, resulting in the variation of solution characters. Viscosity measurement indicates that mixed micelles between the copolymer chain and SDS molecules serving as junction bridges for transitional network remarkably enhance the viscosity. Moreover, the microscopic structures of copolymers at different experimental conditions are conducted by ESEM. This method gives us an insight into the preparation of hydrophobically associative water-soluble copolymers by cationic surfmer-anionic surfactant mixed micellar polymerization with good performance.

  6. Synthesis of water-soluble poly [acrylic acid-co-vinyl butyl ether] and its applications in cement admixtures

    International Nuclear Information System (INIS)

    Negim, S.M.; Mun, G.A.; Nurkeeva, Z.S.; Danveesh, H.H.M.

    2005-01-01

    Three composition ratios of poly[acrylic acid (AA)-co-vinyl butyl ether)] were prepared in alcoholic solution using azo-bis-isobutyro-nitrile as initiator (ABIN). The water-soluble copolymers were characterized through FT-IR, 1 H NMR, Mass spectra, ESEM as well as viscosity. The effect of water-soluble copolymers and their sodium salts on the physico-mechanical properties of Ordaniary Portland Cement (O.P.C) pastes was investigated. The results showed that the addition of aqueous solutions from the prepared copolymers and their sodium salts to the cement improve most of the specific characteristics of (O.P.C). As the concentration of the water-soluble copolymer increases, the setting time increases. The combined water content enhances the addition of copolymer to the mixing water. The compressive strength was she increased at all any hydration. The results of the solution of the prepared sodium salt copolymers are better than its copolymers. (author)

  7. Favorable Alleles for Stem Water-Soluble Carbohydrates Identified by Association Analysis Contribute to Grain Weight under Drought Stress Conditions in Wheat

    Science.gov (United States)

    Li, Runzhi; Chang, Xiaoping; Jing, Ruilian

    2015-01-01

    Drought is a major environmental constraint to crop distribution and productivity. Stem water-soluble carbohydrates (WSC) buffer wheat grain yield against conditions unfavorable for photosynthesis during the grain filling stage. In this study, 262 winter wheat accessions and 209 genome-wide SSR markers were collected and used to undertake association analysis based on a mixed linear model (MLM). The WSC in different internodes at three growth stages and 1000-grain weight (TGW) were investigated under four environmental regimes (well-watered, drought stress during the whole growth period, and two levels of terminal drought stress imposed by chemical desiccation under the well-watered and drought stress during the whole growth period conditions). Under diverse drought stress conditions, WSC in lower internodes showed significant positive correlations with TGW, especially at the flowering stage under well-watered conditions and at grain filling under drought stress. Sixteen novel WSC-favorable alleles were identified, and five of them contributed to significantly higher TGW. In addition, pyramiding WSC favorable alleles was not only effective for obtaining accessions with higher WSC, but also for enhancing TGW under different water regimes. During the past fifty years of wheat breeding, WSC was selected incidentally. The average number of favorable WSC alleles increased from 1.13 in the pre-1960 period to 4.41 in the post-2000 period. The results indicate a high potential for using marker-assisted selection to pyramid WSC favorable alleles in improving WSC and TGW in wheat. PMID:25768726

  8. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    NICO

    radiation balance.4,5 Major water-soluble inorganic ions are associated with atmospheric ... molecular weight carboxylic acids in aerosol samples collected from a rural ... include biomass burning, agriculture, livestock and soil dust. Tropical ...

  9. Water-soluble dietary fibers and cardiovascular disease.

    Science.gov (United States)

    Theuwissen, Elke; Mensink, Ronald P

    2008-05-23

    One well-established way to reduce the risk of developing cardiovascular disease (CVD) is to lower serum LDL cholesterol levels by reducing saturated fat intake. However, the importance of other dietary approaches, such as increasing the intake of water-soluble dietary fibers is increasingly recognized. Well-controlled intervention studies have now shown that four major water-soluble fiber types-beta-glucan, psyllium, pectin and guar gum-effectively lower serum LDL cholesterol concentrations, without affecting HDL cholesterol or triacylglycerol concentrations. It is estimated that for each additional gram of water-soluble fiber in the diet serum total and LDL cholesterol concentrations decrease by -0.028 mmol/L and -0.029 mmol/L, respectively. Despite large differences in molecular structure, no major differences existed between the different types of water-soluble fiber, suggesting a common underlying mechanism. In this respect, it is most likely that water-soluble fibers lower the (re)absorption of in particular bile acids. As a result hepatic conversion of cholesterol into bile acids increases, which will ultimately lead to increased LDL uptake by the liver. Additionally, epidemiological studies suggest that a diet high in water-soluble fiber is inversely associated with the risk of CVD. These findings underlie current dietary recommendations to increase water-soluble fiber intake.

  10. Dissipative Particle Dynamics Study of Electrostatic Self-Assembly in Aqueous Mixtures of Copolymers Containing One Neutral Water-Soluble Block and One Either Positively or Negatively Charged Polyelectrolyte Block

    Czech Academy of Sciences Publication Activity Database

    Šindelka, K.; Limpouchová, Z.; Lísal, Martin; Procházka, K.

    2014-01-01

    Roč. 47, č. 17 (2014), s. 6121-6134 ISSN 0024-9297 R&D Projects: GA ČR(CZ) GA13-02938S; GA MŠk LH12020 Grant - others:GA ČR(CZ) GAP106/12/0143; GA MŠMT(CZ) LK21302; GA MŠMT(CZ) LM2010005; GA MŠMT(CZ) CZ. 1.05/3.2.00/08.0144 Institutional support: RVO:67985858 Keywords : monte-carlo simulations * molecular-dynamics * diblock copolymer Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.800, year: 2014

  11. Synthesis, characterization and fluorescent properties of water-soluble glycopolymer bearing curcumin pendant residues.

    Science.gov (United States)

    Zhang, Haisong; Yu, Meng; Zhang, Hailei; Bai, Libin; Wu, Yonggang; Wang, Sujuan; Ba, Xinwu

    2016-08-01

    Curcumin is a potential natural anticancer drug with low oral bioavailability because of poor water solubility. The aqueous solubility of curcumin is enhanced by means of modification with the carbohydrate units. Polymerization of the curcumin-containing monomer with carbohydrate-containing monomer gives the water-soluble glycopolymer bearing curcumin pendant residues. The obtained copolymers (P1 and P2) having desirable water solubility were well-characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), UV-Vis absorption spectroscopy, and photoluminescence spectroscopy. The copolymer P2 with a molar ratio of 1:6 (curcumin/carbohydrate) calculated from the proton NMR results exhibits a similar anticancer activity compared to original curcumin, which may serve as a potential chemotherapeutic agent in the field of anticancer medicine.

  12. Synthesis and Anchoring of Antineoplastic Ferrocene and Phthalocyanine Derivatives on Water-Soluble Polymeric Drug Carriers Derived from Lysine and Aspartic Acid

    OpenAIRE

    Maree, M. David; Neuse, Eberhard W.; Erasmus, Elizabeth; Swarts, Jannie C.

    2007-01-01

    The general synthetic strategy towards water-soluble biodegradable drug carriers and the properties that they must have are discussed. The syntheses of water-soluble biodegradable copolymers of lysine and aspartic acid as potential drug-delivering devices, having amine-functionalised side chains are then described. Covalent anchoring of carboxylic acid derivatives of the antineoplastic ferrocene and photodynamically active phthalocyanine moieties to the amine-containing drug carrier copolymer...

  13. Bioremediation prospects of fungi isolated from water soluble ...

    African Journals Online (AJOL)

    The fungi associated with water soluble fraction (WSF) of crude oil from two different locations were investigated. The samples were collected from Ezibin oil well (Sample A), Okwagbe village in Ughelli South Local Government Area of Delta State and from NPDC laboratory (Sample B) in Benin City, Oredo Local ...

  14. Plasma concentrations of water.soluble vitamins in metabolic ...

    African Journals Online (AJOL)

    Context: Vitamins B1 (thiamine), B3 (niacin), B6 (pyridoxine), and C (ascorbic acid) are vital for energy, carbohydrate, lipid, and amino acid metabolism and in the regulation of the cellular redox state. Some studies have associated low levels of water.soluble vitamins with metabolic syndrome and its various components.

  15. Some physicochemical aspects of water-soluble mineral flotation.

    Science.gov (United States)

    Wu, Zhijian; Wang, Xuming; Liu, Haining; Zhang, Huifang; Miller, Jan D

    2016-09-01

    Some physicochemical aspects of water-soluble mineral flotation including hydration phenomena, associations and interactions between collectors, air bubbles, and water-soluble mineral particles are presented. Flotation carried out in saturated salt solutions, and a wide range of collector concentrations for effective flotation of different salts are two basic aspects of water-soluble mineral flotation. Hydration of salt ions, mineral particle surfaces, collector molecules or ions, and collector aggregates play an important role in water-soluble mineral flotation. The adsorption of collectors onto bubble surfaces is suggested to be the precondition for the association of mineral particles with bubbles. The association of collectors with water-soluble minerals is a complicated process, which may include the adsorption of collector molecules or ions onto such surfaces, and/or the attachment of collector precipitates or crystals onto the mineral surfaces. The interactions between the collectors and the minerals include electrostatic and hydrophobic interactions, hydrogen bonding, and specific interactions, with electrostatic and hydrophobic interactions being the common mechanisms. For the association of ionic collectors with minerals with an opposite charge, electrostatic and hydrophobic interactions could have a synergistic effect, with the hydrophobic interactions between the hydrophobic groups of the previously associated collectors and the hydrophobic groups of oncoming collectors being an important attractive force. Association between solid particles and air bubbles is the key to froth flotation, which is affected by hydrophobicity of the mineral particle surfaces, surface charges of mineral particles and bubbles, mineral particle size and shape, temperature, bubble size, etc. The use of a collector together with a frother and the use of mixed surfactants as collectors are suggested to improve flotation. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Reduction of facial wrinkles by hydrolyzed water-soluble egg membrane associated with reduction of free radical stress and support of matrix production by dermal fibroblasts

    Directory of Open Access Journals (Sweden)

    Jensen GS

    2016-10-01

    Full Text Available Gitte S Jensen,1 Bijal Shah,2 Robert Holtz,3 Ashok Patel,4 Donald C Lo2 1NIS Labs, Klamath Falls, OR, 2Department of Neurobiology, Center for Drug Discovery, Duke University Medical Center, Durham, NC, 3BioInnovation Laboratories, Inc., Lakewood, CO, 4Centre Manufacturing LLC, Eden Prairie, MN, USA Objective: The aim of this study was to evaluate the effects of water-soluble egg membrane (WSEM on wrinkle reduction in a clinical pilot study and to elucidate specific mechanisms of action using primary human immune and dermal cell-based bioassays.Methods: To evaluate the effects of topical application of WSEM (8% on human skin, an open-label 8-week study was performed involving 20 healthy females between the age of 45 years and 65 years. High-resolution photography and digital analysis were used to evaluate the wrinkle depth in the facial skin areas beside the eye (crow’s feet. WSEM was tested for total antioxidant capacity and effects on the formation of reactive oxygen species by human polymorphonuclear cells. Human keratinocytes (HaCaT cells were used for quantitative polymerase chain reaction analysis of the antioxidant response element genes Nqo1, Gclm, Gclc, and Hmox1. Evaluation of effects on human primary dermal fibroblasts in vitro included cellular viability and production of the matrix components collagen and elastin.Results: Topical use of a WSEM-containing facial cream for 8 weeks resulted in a significant reduction of wrinkle depth (P<0.05. WSEM contained antioxidants and reduced the formation of reactive oxygen species by inflammatory cells in vitro. Despite lack of a quantifiable effect on Nrf2, WSEM induced the gene expression of downstream Nqo1, Gclm, Gclc, and Hmox1 in human keratinocytes. Human dermal fibroblasts treated with WSEM produced more collagen and elastin than untreated cells or cells treated with dbcAMP control. The increase in collagen production was statistically significant (P<0.05.Conclusion: The topical use

  17. Radiculography with water-soluble contraste medium

    International Nuclear Information System (INIS)

    Araujo Pinheiro, R.S. de

    1987-01-01

    The etiologic diagnosis of the lumbar pain is discussed. The radiculography with water-soluble contrast medium is used and 250 cases are studied. Some practical criteria of indication executation and interpretation of the examination are reported. (M.A.C.) [pt

  18. Oxidative potential of ambient water-soluble PM2.5 in the southeastern United States: contrasts in sources and health associations between ascorbic acid (AA and dithiothreitol (DTT assays

    Directory of Open Access Journals (Sweden)

    T. Fang

    2016-03-01

    Full Text Available The ability of certain components of particulate matter to induce oxidative stress through the generation of reactive oxygen species (ROS in vivo may be one mechanism accounting for observed linkages between ambient aerosols and adverse health outcomes. A variety of assays have been used to measure this so-called aerosol oxidative potential. We developed a semi-automated system to quantify oxidative potential of filter aqueous extracts utilizing the dithiothreitol (DTT assay and report here the development of a similar semi-automated system for the ascorbic acid (AA assay. Approximately 500 PM2.5 filter samples collected in contrasting locations in the southeastern US were analyzed for a host of aerosol species, along with AA and DTT activities. We present a detailed contrast in findings from these two assays. Water-soluble AA activity was higher in summer and fall than in winter, with highest levels near heavily trafficked highways, whereas DTT activity was higher in winter compared to summer and fall and more spatially homogeneous. AA activity was nearly exclusively correlated with water-soluble Cu (r  =  0.70–0.94 at most sites, whereas DTT activity was correlated with organic and metal species. Source apportionment models, positive matrix factorization (PMF and a chemical mass balance method with ensemble-averaged source impact profiles (CMB-E, suggest a strong contribution from traffic emissions and secondary processes (e.g., organic aerosol oxidation or metals mobilization by secondary acids to both AA and DTT activities in urban Atlanta. In contrast, biomass burning was a large source for DTT activity, but insignificant for AA. AA activity was not correlated with PM2.5 mass, while DTT activity co-varied strongly with mass (r  =  0.49–0.86 across sites and seasons. Various linear models were developed to estimate AA and DTT activities for the central Atlanta Jefferson Street site, based on the CMB-E sources. The

  19. PM 2.5-10, PM 2.5 and associated water-soluble inorganic species at a coastal urban site in the metropolitan region of Rio de Janeiro

    Science.gov (United States)

    Mariani, Rauda L.; de Mello, William Z.

    The concentrations of PM 2.5-10, PM 2.5 and associated water-soluble inorganic species (WSIS) were determined in a coastal site of the metropolitan region of Rio de Janeiro, Southeastern Brazil, from October 1998 to September 1999 ( n=50). Samples were dissolved in water and analyzed for major inorganic ions. The mean (± standard deviation; median) concentrations of PM 2.5-10 and PM 2.5 were, respectively, 26 (± 16; 21) μg m -3 and 17 (± 13; 14) μg m -3. Their mean concentrations were 1.7-1.8 times higher in dry season (May-October) than in rainy season (November-April). The WSIS comprised, respectively, 34% and 28% of the PM 2.5-10 and PM 2.5 masses. Chloride, Na + and Mg 2+ were the predominant ions in PM 2.5-10, indicating a significant influence of sea-salt aerosols. In PM 2.5, SO 42- (˜97% nss-SO 42-) and NH 4+ were the most abundant ions and their equivalent concentration ratio (SO 42-/NH 4+ ˜1.0) suggests that they were present as (NH 4) 2SO 4 particles. The mean concentration of (NH 4) 2SO 4 was 3.4 μg m -3. The mean equivalent PM 2.5 NO 3- concentration was eight times smaller than those of SO 42- and NH 4+. The PM 2.5 NO 3- concentration in dry season was three times higher than in rainy season, probably due to reaction of NaCl (sea salt) with HNO 3 as a result of higher levels of NO y during the dry season and/or reduced volatilization of NH 4NO 3 due to lower wintertime temperature. Chloride depletion was observed in both size ranges, although more pronouncely in PM 2.5.

  20. Responsive copolymers for enhanced petroleum recovery. Second annual report

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, C.; Hester, R.

    1995-05-01

    The authors describe second year efforts in synthesis, characterization, and rheology to develop polymers with significantly improved efficiency in mobility control and conformance. These advanced polymer systems would maintain high viscosities or behave as virtual gels under low shear conditions and at elevated electrolyte concentrations. At high fluid shear rates, associates would deaggregate yielding low viscosity solutions, reducing problems of shear degradation or face plugging during injection. Polymeric surfactants were also developed with potential for use in higher salt, higher temperature reservoirs for mobilization of entrapped oil. Chapters include: Ampholytic terpolymers of acrylamide with sodium 3-acrylamido-3-methylbutanoate and 2-acrylamido-2-methylpropanetrimethylammonium chloride; Hydrophilic sulfobetaine copolymers of acrylamide and 3-(2-acrylamido-methylpropane-dimethylammonio)-1-propanesulfonate; Copolymerization of maleic anhydride and N-vinylformamide; Reactivity ratio of N-vinylformamide with acrylamide, sodium acrylate, and n-butyl acrylate; Effect of the distribution of the hydrophobic cationic monomer dimethyldodecyl(2-acrylamidoethyl)ammonium bromide on the solution behavior of associating acrylamide copolymers; Effect of surfactants on the solution properties of amphipathic copolymers of acrylamide and N,N-dimethyl-N-dodecyl-N-(2-acrylamidoethyl)ammonium bromide; Associative interactions and photophysical behavior of amphiphilic terpolymers prepared by modification of maleic anhydride/ethyl vinyl ether copolymers; Copolymer compositions of high-molecular-weight functional acrylamido water-soluble polymers using direct-polarization magic-angle spinning {sup 13}C NMR; Use of factorial experimental design in static and dynamic light scattering characterization of water soluble polymers; and Porous medium elongational rheometer studies of NaAMB/AM copolymer solutions.

  1. Thermoresponsive behavior of chitosan-g-N-isopropylacrylamide copolymer solutions.

    Science.gov (United States)

    Recillas, Maricarmen; Silva, Luisa L; Peniche, Carlos; Goycoolea, Francisco M; Rinaudo, Marguerite; Argüelles-Monal, Waldo M

    2009-06-08

    Chitosan-g-N-isopropylacrylamide (NIPAm) water-soluble copolymers were synthesized and characterized by FTIR and (1)H NMR spectroscopies combined with conductometric and potentiometric titrations. Their thermoresponsive, fully reversible, behavior in aqueous solutions was characterized by means of microcalorimetry and rheology. During heating of copolymer solutions there is a well-known endothermic effect, which coincides with a marked increase in G' and a moderate decrement in G'' due to the formation of a hydrophobic network at the expense of the net amount of sol fraction. It was also found that a straight dependence between the values of G' above the LCST and the enthalpies associated with the transition reflecting that the connectivity in the gel network is governed by the net number of formed enthalpic-hydrophobic driven-junctions. Both the LCST and the enthalpy change vary with the ionic strength of copolymer solutions, but no dependence was found with the neutralization of the polyelectrolyte chain.

  2. Solution Properties of Water-Soluble “Smart” Poly(N-acryloyl-N′-ethyl piperazine-co-methyl methacrylate

    Directory of Open Access Journals (Sweden)

    G. Roshan Deen

    2012-01-01

    Full Text Available Water-soluble copolymers of N-acryloyl-N′-ethylpiperazine (AcrNEP with methyl methacrylate (MMA were synthesized to high conversion by free-radical solution polymerization. The composition of the copolymers was determined using Fourier Transform Infra-red Spectroscopy (FTIR. Copolymers containing AcrNEP content above 44 mol% were readily soluble in water and exhibited the critical solution temperature behavior. The copolymers were strongly responsive to changes in pH of the external medium due to the presence of tertiary amine functions that could be protonated at low pH. The influence of various factors such as copolymer composition, pH, temperature, salt and surfactant concentration on the LCST of the copolymers were systematically studied. The intrinsic viscosity of the copolymers in dimethyl formamide decreased with increase in temperature due to a decrease in thermodynamic affinity between polymer chains and solvent molecules. The viscosity behavior of the copolymers in sodium chloride solution was similar to that of classical polyelectrolytes and hydrophobically modified polyacrylate systems.

  3. Teratogenicity and metabolism of water-soluble forms of vitamin A in the pregnant rat

    International Nuclear Information System (INIS)

    Gunning, D.B.; Barua, A.B.; Olson, J.A.

    1990-01-01

    Retinoyl β-glucuronide, unlike retinoic acid, has been shown to be non-teratogenic when administered orally, even in large doses, to pregnant rats. The degree to which water-solubility is associated with low teratogenicity is not known. Other water-soluble forms of vitamin A have now been synthesized in our laboratory and are being evaluated for teratogenicity. New water-soluble forms of vitamin A were administered orally to pregnant Sprague-Dawley rats in a single dose of 0.35 mmole/kg bw on day 8 of gestation. On day 19, the dams were sacrificed and the litters were examined. Control animals received either vehicle only or an equivalent dose of all-trans retinoic acid. Maternal and fetal tissues were taken and analyzed by HPLC for vitamin A metabolites. In another experiment, a large single oral dose of the radiolabelled water-soluble compound was administered on day 10. At either 30 minutes or 1 hour after the dose, dams were sacrificed and the embryos analyzed both for radioactivity and for specific metabolites. In contrast to retinoyl β-glucuronide, retinoyl β-glucose is highly teratogenic under identical conditions. Thus, water-solubility does not seem to be the determining factor in the teratogenicity of retinoic acid conjugates

  4. Lipid nanoparticles for administration of poorly water soluble neuroactive drugs.

    Science.gov (United States)

    Esposito, Elisabetta; Drechsler, Markus; Mariani, Paolo; Carducci, Federica; Servadio, Michela; Melancia, Francesca; Ratano, Patrizia; Campolongo, Patrizia; Trezza, Viviana; Cortesi, Rita; Nastruzzi, Claudio

    2017-09-01

    This study describes the potential of solid lipid nanoparticles and nanostructured lipid carriers as nano-formulations to administer to the central nervous system poorly water soluble drugs. Different neuroactive drugs, i.e. dimethylfumarate, retinyl palmitate, progesterone and the endocannabinoid hydrolysis inhibitor URB597 have been studied. Lipid nanoparticles constituted of tristearin or tristearin in association with gliceryl monoolein were produced. The nanoencapsulation strategy allowed to obtain biocompatible and non-toxic vehicles, able to increase the solubility of the considered neuroactive drugs. To improve URB597 targeting to the brain, stealth nanoparticles were produced modifying the SLN surface with polysorbate 80. A behavioural study was conducted in rats to test the ability of SLN containing URB597 given by intranasal administration to alter behaviours relevant to psychiatric disorders. URB597 maintained its activity after nanoencapsulation, suggesting the possibility to propose this kind of vehicle as alternative to unphysiological mixtures usually employed for animal and clinical studies.

  5. Solubilization of poorly water-soluble drugs using solid dispersions.

    Science.gov (United States)

    Tran, Thao T-D; Tran, Phuong H-L; Khanh, Tran N; Van, Toi V; Lee, Beom-Jin

    2013-08-01

    Many new drugs have been discovered in pharmaceutical industry and exposed their surprised potential therapeutic effects. Unfortunately, these drugs possess low absorption and bioavailability since their solubility limitation in water. Solid dispersion (SD) is the current technique gaining so many attractions from scientists due to its effect on improving solubility and dissolution rate of poorly water-soluble drugs. A number of patents including the most recent inventions have been undertaken in this review to address various respects of this strategy in solubilization of poorly watersoluble drugs including type of carriers, preparation methods and view of technologies used to detect SD properties and mechanisms with the aim to accomplish a SD not only effective on enhanced bioavailability but also overcome difficulties associated with stability and production. Future prospects are as well discussed with an only hope that many developments and researches in this field will be successfully reached and contributed to commercial use for treatment as much as possible.

  6. Case study of water-soluble metal containing organic constituents of biomass burning aerosol

    Science.gov (United States)

    Alexandra L. Chang-Graham; Luisa T. M. Profeta; Timothy J. Johnson; Robert J. Yokelson; Alexander Laskin; Julia Laskin

    2011-01-01

    Natural and prescribed biomass fires are a major source of aerosols that may persist in the atmosphere for several weeks. Biomass burning aerosols (BBA) can be associated with long-range transport of water-soluble N-, S-, P-, and metal-containing species. In this study, BBA samples were collected using a particle-into-liquid sampler (PILS) from laboratory burns of...

  7. Study on REE bound water-soluble polysaccharides in plant

    International Nuclear Information System (INIS)

    Wang Yuqi; Guo Fanqing; Xu Lei; Chen Hongmin; Sun Jingxin; Cao Guoyin

    1999-01-01

    The binding of REE with water-soluble polysaccharides (PSs) in leaves of fern Dicranopteris Dichotoma (DD) has been studied by molecular activation analysis. The cold-water-soluble and hot-water-soluble PSs in leaves of DD were obtained by using biochemical separation techniques. The PSs of non-deproteinization and deproteinization, were separated on Sephadex G-200 gel permeation chromatography. The absorption curves of elution for the PSs were obtained by colorimetry, and the proteins were detected using Coomassic brilliant G-250. Eight REEs (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu) in these PSs were determined by instrumental neutron activation analysis. The results obtained show that the REEs are bound firmly with the water-soluble PSs in the plant. A measurement demonstrates that the PSs bound with REEs are mainly of smaller molecular weight (10,000 to 20,000 Dalton)

  8. Characterization of Gasolines, Diesel Fuels and Their Water Soluble Fractions

    Science.gov (United States)

    1983-09-01

    Hutchinson, et al.,1979 ) with the marine algae, Chlorella vulgaris and Chlamydomonas angulosa, suggests that the toxicity of hydrocarbons is a...water-soluble petroleum components on the growth of Chlorella vulgaris Beijernck. Environ. Poll. 9: 157. Morrow, J.E., et al. 1975. Effects of some...P.B., and T.C. Hutchison. 1975. The effects of water-soluble petroleum components on the growth of Chlorella vulqaris Beijerinck. Environ. Poll. 9

  9. Mechanisms for oral absorption of poorly water-soluble compounds

    DEFF Research Database (Denmark)

    Lind, Marianne Ladegaard

    Abstract A large part of the new drug candidates discovered by the pharmaceutical industry have poor solubility in aqueous media. The preferred route of drug administration is the oral route, but for these poorly water-soluble drug candidates the oral bioavailability can be low and variable. Often......, phospholipids) and exogenous surfactants used in pharmaceutical formulations on the oral absorption of poorly water-soluble drug substances. Three different models were used for this purpose. The first model was the in vitro Caco-2 cell model. Simulated intestinal fluids which did not decrease cellular...... products are important for the solubilization of poorly water-soluble drug substances and thus absorption. The second model used was the lipoprotein secreting Caco-2 cell model, which was used to simulate intestinal lymphatic transport in vitro. Various simulated intestinal fluids were composed...

  10. The guanidinium group as a key part of water-soluble polymer carriers for siRNA complexation and protection against degradation.

    Science.gov (United States)

    Tabujew, Ilja; Freidel, Christoph; Krieg, Bettina; Helm, Mark; Koynov, Kaloian; Müllen, Klaus; Peneva, Kalina

    2014-07-01

    Here, the preparation of a novel block copolymer consisting of a statistical copolymer N-(2-hydroxypropyl) methacrylamide-s-N-(3-aminopropyl) methacrylamide and a short terminal 3-guanidinopropyl methacrylamide block is reported. This polymer structure forms neutral but water-soluble nanosized complexes with siRNA. The siRNA block copolymer complexes are first analyzed using agarose gel electrophoresis and their size is determined with fluorescence correlation spectroscopy. The protective properties of the polymer against RNA degradation are investigated by treating the siRNA block copolymer complexes with RNase V1. Heparin competition assays confirm the efficient release of the cargo in vitro. In addition, the utilization of microscale thermophoresis is demonstrated for the determination of the binding strength between a fluorescently labeled polyanion and a polymer molecule. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Water-soluble resorcin[4]arene based cavitands

    NARCIS (Netherlands)

    Grote gansey, M.H.B.; Grote Gansey, Marcel H.B.; Bakker, Frank K.G.; Feiters, Martinus C.; Geurts, Hubertus P.M.; Verboom, Willem; Reinhoudt, David

    1998-01-01

    Water-soluble resorcin[4]arene based cavitands were obtained in good yields by reaction of bromomethylcavitands with pyridine. Their solubility was determined by conductometry. The behaviour in water depends on the alkyl chain length; the methylcavitand does not aggregate, whereas the pentyl- and

  12. Physical and ionic characteristics in water soluble fraction (WSF) of ...

    African Journals Online (AJOL)

    The values of ionic and physical characteristics at 25, 50 and 100% water soluble fraction (WSF) of Olomoro well-head crude oil before and after exposure to Azolla africana were investigated. The WSF values before and after exposure to the plants showed that more ions were available after the introduction of the test plant.

  13. Process for radiation cocrosslinking water soluble polymers and products thereof

    International Nuclear Information System (INIS)

    Assarsson, P.G.; King, P.A.

    1976-01-01

    Poly(ethylene oxide) and at least one other water soluble polymer are conveniently cocrosslinked by exposing aqueous systems of the polymers to high energy irradiation. The resulting products are insoluble hydrophilic gels which can contain or when dried absorb large quantities of aqueous fluids and hence are useful as absorbing media for disposable absorbent articles, agricultural applications and the like

  14. Water-soluble diphosphadiazacyclooctanes as ligands for aqueous organometallic catalysis

    KAUST Repository

    Boulanger, Jérôme

    2012-12-01

    Two new water-soluble diphosphacyclooctanes been synthesized and characterized by NMR and surface tension measurements. Both phosphanes proved to coordinate rhodium in a very selective way as well-defined bidentates were obtained. When used in Rh-catalyzed hydroformylation of terminal alkenes, both ligands positively impacted the reaction chemoselectivity. © 2012 Elsevier B.V.

  15. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    Atmospheric aerosol samples of PM2.5 and PM10 were collected in April–May 2011 from a rural site in Tanzania and analyzed for water-soluble inorganic ions and low molecular weight carboxylic acids using ion chromatography. PM2.5 and PM10 low-volume samplers with quartz fibre filters were deployed and aerosol ...

  16. Aggregation and Photophysical Properties of Water-Soluble Sapphyrins

    Czech Academy of Sciences Publication Activity Database

    Kubát, Pavel; Lang, Kamil; Zelinger, Zdeněk; Král, V.

    2004-01-01

    Roč. 395, - (2004), s. 82-86 ISSN 0009-2614 R&D Projects: GA AV ČR KSK4040110 Keywords : water-soluble * sapphyrins * photophysical Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.438, year: 2004

  17. Leaching behavior of water-soluble carbohydrates from almond hulls

    Science.gov (United States)

    Over 58% of the dry matter content of the hulls from the commercial almond (Prunus dulcis (Miller) D.A. Webb) is soluble in warm water (50-70°C) extraction. The water-soluble extractables include useful amounts of fermentable sugars (glucose, fructose, sucrose), sugar alcohols (inositol and sorbito...

  18. Short Communication Relationships between the water solubility of ...

    African Journals Online (AJOL)

    132. Short Communication. Relationships between the water solubility of roughage dry matter and certain chemical characteristics. J.W. Cilliers- and H.J. Cilliers. North West Agricultural Development lnstitute, Private. Bag X804, Potchefstroom, 2520 Republic of South Africa. Received 17 May 1995; accepted 8 August 1995.

  19. Synthesis of water soluble photo-initiators of thioxanthone derivatives

    International Nuclear Information System (INIS)

    Qi Guozhen; Wang Jindi; Lin Yiqing

    1999-01-01

    Eight new photo-initiators of water-soluble thioxanthone derivatives were prepared. These compounds were identified by IR, NMR, MS and elemental analysis etc. The UV absorption wavelength, molar absorption coefficient and fluorescent quantum yield were determined. Furthermore, the relationship between structure and properties was discussed

  20. Synthesis of water soluble photo-initiators of thioxanthone derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Guozhen, Qi; Jindi, Wang; Yiqing, Lin [Inst. of Fine Chemicals ECUST, Shanghai (China)

    1999-07-01

    Eight new photo-initiators of water-soluble thioxanthone derivatives were prepared. These compounds were identified by IR, NMR, MS and elemental analysis etc. The UV absorption wavelength, molar absorption coefficient and fluorescent quantum yield were determined. Furthermore, the relationship between structure and properties was discussed.

  1. Water-soluble diphosphadiazacyclooctanes as ligands for aqueous organometallic catalysis

    KAUST Repository

    Boulanger, Jé rô me; Bricout, Hervé ; Tilloy, Sé bastien; Fihri, Aziz; Len, Christophe; Hapiot, Fré dé ric; Monflier, É ric

    2012-01-01

    Two new water-soluble diphosphacyclooctanes been synthesized and characterized by NMR and surface tension measurements. Both phosphanes proved to coordinate rhodium in a very selective way as well-defined bidentates were obtained. When used in Rh-catalyzed hydroformylation of terminal alkenes, both ligands positively impacted the reaction chemoselectivity. © 2012 Elsevier B.V.

  2. Selective Photooxidation Reactions using Water-Soluble Anthraquinone Photocatalysts

    NARCIS (Netherlands)

    Zhang, W.; Gacs, Jenő; Arends, I.W.C.E.; Hollmann, F.

    2017-01-01

    The aerobic organocatalytic oxidation of alcohols was achieved by using water-soluble sodium anthraquinone sulfonate. Under visible-light activation, this catalyst mediated the aerobic oxidation of alcohols to aldehydes and ketones. The photo-oxyfunctionalization of alkanes was also possible

  3. Twenty-four-hour urinary water-soluble vitamin levels correlate with their intakes in free-living Japanese schoolchildren.

    Science.gov (United States)

    Tsuji, Tomiko; Fukuwatari, Tsutomu; Sasaki, Satoshi; Shibata, Katsumi

    2011-02-01

    To examine the association between 24 h urinary water-soluble vitamin levels and their intakes in free-living Japanese schoolchildren. All foods consumed for four consecutive days were recorded accurately by a weighed food record. A single 24 h urine sample was collected on the fourth day, and the urinary levels of water-soluble vitamins were measured. An elementary school in Inazawa City, Japan. A total of 114 healthy, free-living, Japanese elementary-school children aged 10-12 years. The urinary level of each water-soluble vitamin was correlated positively to its mean intake in the past 2-4 d (vitamin B1: r = 0·42, P vitamin B2: r = 0·43, P vitamin B6: r = 0·49, P vitamin C: r = 0·39, P vitamin B12 (r = 0·10, P = NS). Estimated mean intakes of water-soluble vitamins calculated using urinary levels and recovery rates were 97-102 % of their 3 d mean intake, except for vitamin B12 (79 %). The results show that urinary levels of water-soluble vitamins, except for vitamin B12, reflected their recent intakes in free-living Japanese schoolchildren and could be used as a potential biomarker to estimate mean vitamin intake.

  4. Application of various water soluble polymers in gas hydrate inhibition

    DEFF Research Database (Denmark)

    Kamal, Muhammad Shahzad; Hussein, Ibnelwaleed A.; Sultan, Abdullah S.

    2016-01-01

    . This review presents the various types of water soluble polymers used for hydrate inhibition, including conventional and novel polymeric inhibitors along with their limitations. The review covers the relevant properties of vinyl lactam, amide, dendrimeric, fluorinated, and natural biodegradable polymers....... The factors affecting the performance of these polymers and the structure-property relationships are reviewed. A comprehensive review of the techniques used to evaluate the performance of the polymeric inhibitors is given. This review also addresses recent developments, current and future challenges...

  5. Extraction vitamins of group B water-soluble polymers

    Directory of Open Access Journals (Sweden)

    Y. I. Korenman

    2012-01-01

    Full Text Available General lows of extraction of B vitamins in aquatic environments of the solution of polymers (poly-N-vinylpyrrolidone, poly-N-vinilkaprolaktam has been studied. The influence of polymer concentration and structure on the distribution coefficients and degree of extraction of vitamins has been established. As a result, the direct search of a stable two-phase systems based on water-soluble polymers has been developed effective systems for the extraction of vitamin B from aqueous salt solutions.

  6. Water soluble vitamins and peritoneal dialysis - State of the art.

    Science.gov (United States)

    Jankowska, Magdalena; Lichodziejewska-Niemierko, Monika; Rutkowski, Bolesław; Dębska-Ślizień, Alicja; Małgorzewicz, Sylwia

    2017-12-01

    This review presents the results of a systematic literature search concerning water soluble vitamins and peritoneal dialysis modality. We provide an overview of the data available on vitamin requirements, dietary intake, dialysis related losses, metabolism and the benefits of supplementation. We also summarise the current recommendations concerning the supplementation of vitamins in peritoneal dialysis and discuss the safety of an administration of vitamins in pharmacological doses. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  7. Polyelectrolyte microcapsules for sustained delivery of water-soluble drugs

    Energy Technology Data Exchange (ETDEWEB)

    Anandhakumar, S.; Debapriya, M. [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India); Nagaraja, V. [Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012 (India); Raichur, Ashok M., E-mail: amr@materials.iisc.ernet.in [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India)

    2011-03-12

    Polyelectrolyte capsules composed of weak polyelectrolytes are introduced as a simple and efficient system for spontaneous encapsulation of low molecular weight water-soluble drugs. Polyelectrolyte capsules were prepared by layer-by-layer (LbL) assembling of weak polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) on polystyrene sulfonate (PSS) doped CaCO{sub 3} particles followed by core removal with ethylene-diaminetetraacetic acid (EDTA). The loading process was observed by confocal laser scanning microscopy (CLSM) using tetramethylrhodamineisothiocyanate labeled dextran (TRITC-dextran) as a fluorescent probe. The intensity of fluorescent probe inside the capsule decreased with increase in cross-linking time. Ciprofloxacin hydrochloride (a model water-soluble drug) was spontaneously deposited into PAH/PMA capsules and their morphological changes were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The quantitative study of drug loading was also elucidated which showed that drug loading increased with initial drug concentration, but decreased with increase in pH. The loaded drug was released in a sustained manner for 6 h, which could be further extended by cross-linking the capsule wall. The released drug showed significant antibacterial activity against E. coli. These findings indicate that such capsules can be potential carriers for water-soluble drugs in sustained/controlled drug delivery applications.

  8. Polyelectrolyte microcapsules for sustained delivery of water-soluble drugs

    International Nuclear Information System (INIS)

    Anandhakumar, S.; Debapriya, M.; Nagaraja, V.; Raichur, Ashok M.

    2011-01-01

    Polyelectrolyte capsules composed of weak polyelectrolytes are introduced as a simple and efficient system for spontaneous encapsulation of low molecular weight water-soluble drugs. Polyelectrolyte capsules were prepared by layer-by-layer (LbL) assembling of weak polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) on polystyrene sulfonate (PSS) doped CaCO 3 particles followed by core removal with ethylene-diaminetetraacetic acid (EDTA). The loading process was observed by confocal laser scanning microscopy (CLSM) using tetramethylrhodamineisothiocyanate labeled dextran (TRITC-dextran) as a fluorescent probe. The intensity of fluorescent probe inside the capsule decreased with increase in cross-linking time. Ciprofloxacin hydrochloride (a model water-soluble drug) was spontaneously deposited into PAH/PMA capsules and their morphological changes were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The quantitative study of drug loading was also elucidated which showed that drug loading increased with initial drug concentration, but decreased with increase in pH. The loaded drug was released in a sustained manner for 6 h, which could be further extended by cross-linking the capsule wall. The released drug showed significant antibacterial activity against E. coli. These findings indicate that such capsules can be potential carriers for water-soluble drugs in sustained/controlled drug delivery applications.

  9. Effect of surfactants on the fluorescence spectra of water-soluble ...

    Indian Academy of Sciences (India)

    TECS

    Effect of surfactants on the fluorescence spectra of water-soluble. MEHPPV ... polyacrylic acid (PAA) chains grafted onto their backbone were found to be water soluble, and they exhi- ..... in other words the variation of emission intensity.

  10. Water-soluble vitamin homeostasis in fasting northern elephant seals (Mirounga angustirostris) measured by metabolomics analysis and standard methods.

    Science.gov (United States)

    Boaz, Segal M; Champagne, Cory D; Fowler, Melinda A; Houser, Dorian H; Crocker, Daniel E

    2012-02-01

    Despite the importance of water-soluble vitamins to metabolism, there is limited knowledge of their serum availability in fasting wildlife. We evaluated changes in water-soluble vitamins in northern elephant seals, a species with an exceptional ability to withstand nutrient deprivation. We used a metabolomics approach to measure vitamins and associated metabolites under extended natural fasts for up to 7 weeks in free-ranging lactating or developing seals. Water-soluble vitamins were not detected with this metabolomics platform, but could be measured with standard assays. Concentrations of measured vitamins varied independently, but all were maintained at detectable levels over extended fasts, suggesting that defense of vitamin levels is a component of fasting adaptation in the seals. Metabolomics was not ideal for generating complete vitamin profiles in this species, but gave novel insights into vitamin metabolism by detecting key related metabolites. For example, niacin level reductions in lactating females were associated with significant reductions in precursors suggesting downregulation of the niacin synthetic pathway. The ability to detect individual vitamins using metabolomics may be impacted by the large number of novel compounds detected. Modifications to the analysis platforms and compound detection algorithms used in this study may be required for improving water-soluble vitamin detection in this and other novel wildlife systems. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Water-soluble vitamin homeostasis in fasting northern elephant seals (Mirounga angustirostris) measured by metabolomics analysis and standard methods

    Science.gov (United States)

    Boaz, Segal M.; Champagne, Cory D.; Fowler, Melinda A.; Houser, Dorian H.; Crocker, Daniel E.

    2011-01-01

    Despite the importance of water-soluble vitamins to metabolism, there is limited knowledge of their serum availability in fasting wildlife. We evaluated changes in water-soluble vitamins in northern elephant seals, a species with an exceptional ability to withstand nutrient deprivation. We used a metabolomics approach to measure vitamins and associated metabolites under extended natural fasts for up to seven weeks in free-ranging lactating or developing seals. Water-soluble vitamins were not detected with this metabolomics platform, but could be measured with standard assays. Concentrations of measured vitamins varied independently, but all were maintained at detectable levels over extended fasts, suggesting that defense of vitamin levels is a component of fasting adaptation in the seals. Metabolomics was not ideal for generating complete vitamin profiles in this species, but gave novel insights into vitamin metabolism by detecting key related metabolites. For example, niacin level reductions in lactating females were associated with significant reductions in precursors suggesting downregulation of the niacin synthetic pathway. The ability to detect individual vitamins using metabolomics may be impacted by the large number of novel compounds detected. Modifications to the analysis platforms and compound detection algorithms used in this study may be required for improving water-soluble vitamin detection in this and other novel wildlife systems. PMID:21983145

  12. Association and Structure of Thermo Sensitive Comblike Block Copolymers in Aqueous Solutions

    International Nuclear Information System (INIS)

    Cheng, Gang

    2008-01-01

    The structures and association properties of thermo sensitive poly(methoxyoligo(ethylene glycol) norbornenyl esters) block copolymers in D2O were investigated by Small Angle Neutron Scattering (SANS). Each block is a comb-like polymer with a polynorbornene (PNB) backbone and oligo ethylene glycol (OEG) side chains (one side chain per NB monomer). The chemical formula of the block copolymer is (OEG3NB)79-(OEG6.6NB)67, where subscripts represent the degree of polymerization (DP) of OEG and NB in each block The polymer concentration was fixed at 2.0 wt % and the structural changes were investigated over a temperature range between 25 C and 68 C. It was found that at room temperature polymers associate to form micelles with a spherical core formed by the block (OEG3NB)79 and corona formed by the block (OEG6.6NB)67 and that the shape of the polymer in the corona could be described by the form factor of rigid cylinders. At elevated temperatures, the aggregation number increases and the micelles become more compact. At temperatures round the cloud point temperature (CPT) T = 60 C a correlation peak started to appear and became pronounced at 68 C due to the formation of a partially ordered structure with a correlation length ∼ 349

  13. Nanonization strategies for poorly water-soluble drugs.

    Science.gov (United States)

    Chen, Huabing; Khemtong, Chalermchai; Yang, Xiangliang; Chang, Xueling; Gao, Jinming

    2011-04-01

    Poor water solubility for many drugs and drug candidates remains a major obstacle to their development and clinical application. Conventional formulations to improve solubility suffer from low bioavailability and poor pharmacokinetics, with some carriers rendering systemic toxicities (e.g. Cremophor(®) EL). In this review, several major nanonization techniques that seek to overcome these limitations for drug solubilization are presented. Strategies including drug nanocrystals, nanoemulsions and polymeric micelles are reviewed. Finally, perspectives on existing challenges and future opportunities are highlighted. Published by Elsevier Ltd.

  14. A novel pH sensitive water soluble fluorescent nanomicellar sensor for potential biomedical applications.

    Science.gov (United States)

    Georgiev, Nikolai I; Bryaskova, Rayna; Tzoneva, Rumiana; Ugrinova, Iva; Detrembleur, Christophe; Miloshev, Stoyan; Asiri, Abdullah M; Qusti, Abdullah H; Bojinov, Vladimir B

    2013-11-01

    Herein we report on the synthesis and sensor activity of a novel pH sensitive probe designed as highly water-soluble fluorescent micelles by grafting of 1,8-naphthalimide-rhodamine bichromophoric FRET system (RNI) to the PMMA block of a well-defined amphiphilic diblock copolymer-poly(methyl methacrylate)-b-poly(methacrylic acid) (PMMA48-b-PMAA27). The RNI-PMMA48-b-PMAA27 adduct is capable of self-assembling into micelles with a hydrophobic PMMA core, containing the anchored fluorescent probe, and a hydrophilic shell composed of PMAA block. Novel fluorescent micelles are able to serve as a highly sensitive pH probe in water and to internalize successfully HeLa and HEK cells. Furthermore, they showed cell specificity and significantly higher photostability than that of a pure organic dye label such as BODIPY. The valuable properties of the newly prepared fluorescent micelles indicate the high potential of the probe for future biological and biomedical applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Water-Soluble Vitamin E-Tocopheryl Phosphate.

    Science.gov (United States)

    Zingg, Jean-Marc

    The hydrophobicity of vitamin E poses transport and metabolic challenges to regulate its bioavailability and to prevent its accumulation in lipid-rich tissues such as adipose tissue, brain, and liver. Water-soluble precursors of vitamin E (α-tocopherol, αT), such as its esters with acetate (αTA), succinate (αTS), or phosphate (αTP), have increased solubility in water and stability against reaction with free radicals, but they are rapidly converted during their uptake into the lipid-soluble vitamin E. Therefore, the bioavailability of these precursors as intact molecules is low; nevertheless, at least for αTS and αTP, the recent research has revealed unique regulatory effects on signal transduction and gene expression and the modulation of cellular events ranging from proliferation, survival/apoptosis, lipid uptake and metabolism, phagocytosis, long term potentiation, cell migration, telomere maintenance, and angiogenesis. Moreover, water-soluble derivatives of vitamin E including some based on αTP are increasingly used as components of nanocarriers for enhanced and targeted delivery of drugs and other molecules (vitamins, including αT and αTP itself, vitamin D3, carnosine, caffeine, docosahexaenoic acid (DHA), insulin) and cofactors such as coenzyme Q10. In this review, the chemical characteristics, transport, metabolic pathways, and molecular mechanisms of action of αTP in cells and tissues are summarized and put into perspective with its possible role in the prevention of a number of diseases. © 2018 Elsevier Inc. All rights reserved.

  16. Water-soluble, triflate-based, pyrrolidinium ionic liquids

    International Nuclear Information System (INIS)

    Moreno, M.; Montanino, M.; Carewska, M.; Appetecchi, G.B.; Jeremias, S.; Passerini, S.

    2013-01-01

    Highlights: • Water-soluble, pyrrolidinium triflate ILs as solvents for extraction processes. • Electrolyte components for high safety, electrochemical devices. • Effect of the oxygen atom in the alkyl main side chain of pyrrolidinium cation. -- Abstract: The physicochemical and electrochemical properties of the water-soluble, N-methoxyethyl-N-methylpyrrolidinium trifluoromethanesulfonate (PYR 1(2O1) OSO 2 CF 3 ) ionic liquid (IL) were investigated and compared with those of commercial N-butyl-N-methylpyrrolidinium trifluoromethanesulfonate (PYR 14 OSO 2 CF 3 ). The results have shown that the transport properties are well correlated with the rheological and thermal behavior. The incorporation of an oxygen atom in the pyrrolidinium cation aliphatic side chain resulted in enhanced flexibility of the ether side chain, this supporting for the higher ionic conductivity, self-diffusion coefficient and density of PYR 1(2O1) OSO 2 CF 3 with respect to PYR 14 OSO 2 CF 3 , whereas no relevant effect on the crystallization of the ionic liquid was found. Finally, the presence of the ether side chain material in the pyrrolidinium cation led to a reduction in electrochemical stability, particularly on the cathodic verse

  17. Chelating water-soluble polymers for waste minimization

    International Nuclear Information System (INIS)

    Smith, B.; Cournoyer, M.; Duran, B.; Ford, D.; Gibson, R.; Lin, M.; Meck, A.; Robinson, P.; Robison, T.

    1996-01-01

    Within the DOE complex and in industry there is a tremendous need for advanced metal ion recovery and waste minimization techniques. This project sought to employ capabilities for ligand-design and separations chemistry in which one can develop and evaluate water- soluble chelating polymers for recovering actinides and toxic metals from various process streams. Focus of this work was (1) to develop and select a set of water-soluble polymers suitable for a selected waste stream and (2) demonstrate this technology in 2 areas: removal of (a) actinides and toxic RCRA metals from waste water and (b) recovery of Cu and other precious metals from industrial process streams including from solid catalysts and aqueous waste streams. The R ampersand D was done in 4 phases for each of the 2 target areas: polymer synthesis for scaleup, equipment assembly, process demonstration at a DOE or industrial site, and advanced ligand/polymer synthesis. The TA- 50 site at Los Alamos was thought to be appropriate due to logistics and to its being representative of similar problems throughout the DOE complex

  18. Changes in the content of water-soluble sulphur in the soil after an application of straw and elemental sulphur

    Directory of Open Access Journals (Sweden)

    Pavel Ryant

    2007-01-01

    Full Text Available The changes in the content of water-soluble sulphur in the soil after the application of straw and elemental sulphur (ES were explored in a 2-year vegetation pot experiment. The following variants were included in the experiment: 1 unfertilised control; 2 wheat straw; 3 rape straw; 4 ES; 5 wheat straw + ES; 6 rape straw + ES. The two types of straw were applied in a dose of 32 g of dry matter and elemental sulphur was applied in a dose of 0.42 g per pot, i.e. 6 kg of soil. The unsatisfactory C:N ratio in the straw was optimised to 25:1 by adding nitrogen in urea. Soil samples were taken prior to sowing of the model plant (spring wheat in 2005 and white mustard in 2006 and then in regular monthly intervals until harvesting (5 times a year. The content of water-soluble sulphur in the soil was evaluated by multifactorial analysis of variance monitoring the effect of the crop, date of soil sampling, application of straw and elemental sulphur.The contents of water-soluble sulphur differed statistically significantly (P > 0.999 when growing the individual model plants. When growing white mustard in 2006 the amount of available sulphur was by 1/5 higher and could have been partly affected by the warm year 2006, as compared to 2005 when spring wheat was grown. Significant differences (P > 0.999 were also discovered among the dates of soil sampling; higher values were detected before the sowing of model plants, i.e. after incubation in the winter, during vegetation the content of water-soluble sulphur decreased and sulphur showed the significantly highest values at the harvest of model plants. When wheat straw was applied the sulphur content did not increase and this may be associated with the wide C:S ratio, whereas after the application of rape straw the content of water-soluble sulphur increased by one third more than in the unfertilised control. The application of elemental sulphur also significantly increased the amount of water-soluble sulphur in

  19. Template-directed hydrothermal synthesis of hydroxyapatite as a drug delivery system for the poorly water-soluble drug carvedilol

    Science.gov (United States)

    Zhao, Qinfu; Wang, Tianyi; Wang, Jing; Zheng, Li; Jiang, Tongying; Cheng, Gang; Wang, Siling

    2011-09-01

    In order to improve the dissolution rate and increase the bioavailability of a poorly water-soluble drug, intended to be administered orally, the biocompatible and bioactive mesoporous hydroxyapatite (HA) was successfully synthesized. In the present study, mesoporous HA nanoparticles were produced using Pluronic block co-polymer F127 and cetyltrimethylammonium bromide (CTAB) as templates by the hydrothermal method. The obtained mesoporous HA was employed as a drug delivery carrier to investigate the drug storage/release properties using carvedilol (CAR) as a model drug. Characterizations of the raw CAR powder, mesoporous HA and CAR-loaded HA were carried out by the scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, N2 adsorption/desorption, thermogravimetric analysis (TGA), and UV-VIS spectrophotometry. The results demonstrated that CAR was successfully incorporated into the mesoporous HA host. In vitro drug release studies showed that mesoporous HA had a high drug load efficiency and provided immediate release of CAR compared with micronized raw drug in simulated gastric fluid (pH 1.2) and intestinal fluid (pH 6.8). Consequently, mesoporous HA is a good candidate as a drug carrier for the oral delivery of poorly water-soluble drugs.

  20. Template-directed hydrothermal synthesis of hydroxyapatite as a drug delivery system for the poorly water-soluble drug carvedilol

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Qinfu [Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No.103, Wenhua Road, Shenyang 110016 (China); Wang Tianyi [Department of Clinical Pharmacy, School of Pharmacy, Shenyang Pharmaceutical University, No.103, Wenhua Road, Shenyang 110016 (China); Wang Jing [Department of Physical Chemistry, School of Basic Science, Shenyang Pharmaceutical University, No.103, Wenhua Road, Shenyang 110016 (China); Zheng Li; Jiang, Tongying; Cheng Gang [Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No.103, Wenhua Road, Shenyang 110016 (China); Wang Siling, E-mail: silingwang@syphu.edu.cn [Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No.103, Wenhua Road, Shenyang 110016 (China)

    2011-09-15

    In order to improve the dissolution rate and increase the bioavailability of a poorly water-soluble drug, intended to be administered orally, the biocompatible and bioactive mesoporous hydroxyapatite (HA) was successfully synthesized. In the present study, mesoporous HA nanoparticles were produced using Pluronic block co-polymer F127 and cetyltrimethylammonium bromide (CTAB) as templates by the hydrothermal method. The obtained mesoporous HA was employed as a drug delivery carrier to investigate the drug storage/release properties using carvedilol (CAR) as a model drug. Characterizations of the raw CAR powder, mesoporous HA and CAR-loaded HA were carried out by the scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, N{sub 2} adsorption/desorption, thermogravimetric analysis (TGA), and UV-VIS spectrophotometry. The results demonstrated that CAR was successfully incorporated into the mesoporous HA host. In vitro drug release studies showed that mesoporous HA had a high drug load efficiency and provided immediate release of CAR compared with micronized raw drug in simulated gastric fluid (pH 1.2) and intestinal fluid (pH 6.8). Consequently, mesoporous HA is a good candidate as a drug carrier for the oral delivery of poorly water-soluble drugs.

  1. Template-directed hydrothermal synthesis of hydroxyapatite as a drug delivery system for the poorly water-soluble drug carvedilol

    International Nuclear Information System (INIS)

    Zhao Qinfu; Wang Tianyi; Wang Jing; Zheng Li; Jiang, Tongying; Cheng Gang; Wang Siling

    2011-01-01

    In order to improve the dissolution rate and increase the bioavailability of a poorly water-soluble drug, intended to be administered orally, the biocompatible and bioactive mesoporous hydroxyapatite (HA) was successfully synthesized. In the present study, mesoporous HA nanoparticles were produced using Pluronic block co-polymer F127 and cetyltrimethylammonium bromide (CTAB) as templates by the hydrothermal method. The obtained mesoporous HA was employed as a drug delivery carrier to investigate the drug storage/release properties using carvedilol (CAR) as a model drug. Characterizations of the raw CAR powder, mesoporous HA and CAR-loaded HA were carried out by the scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, N 2 adsorption/desorption, thermogravimetric analysis (TGA), and UV-VIS spectrophotometry. The results demonstrated that CAR was successfully incorporated into the mesoporous HA host. In vitro drug release studies showed that mesoporous HA had a high drug load efficiency and provided immediate release of CAR compared with micronized raw drug in simulated gastric fluid (pH 1.2) and intestinal fluid (pH 6.8). Consequently, mesoporous HA is a good candidate as a drug carrier for the oral delivery of poorly water-soluble drugs.

  2. Catalytic hydrotreating of lignin with water-soluble molybdenum catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Osmaa, A.; Johansson, A. (Technical Research Centre of Finland, Espoo (Finland). Lab. of Fuel and Process Technology)

    High yields (61% of the original lignin) of low molecular weight oil (84% of the oil eluted through GC) have been obtained by hydrotreating kraft pine lignin with a water-soluble molybdenum catalyst at 430[degree]C for 60 min. The main compounds in the product oil were phenols (8.7% of the original lignin), cyclohexanes (5.0%), benzenes (3.8%), naphthalenes (4.0%), and phenanthrenes (1.2%). The degree of hydrodeoxygenation was 98%. The quality (measured by GPC and GC) of the product was as good as when using more expensive solid NiMo-CR[sub 2]O[sub 3] catalysts. 30 refs., 6 tabs.

  3. Formulation of poorly water-soluble Gemfibrozil applying power ultrasound.

    Science.gov (United States)

    Ambrus, R; Naghipour Amirzadi, N; Aigner, Z; Szabó-Révész, P

    2012-03-01

    The dissolution properties of a drug and its release from the dosage form have a basic impact on its bioavailability. Solubility problems are a major challenge for the pharmaceutical industry as concerns the development of new pharmaceutical products. Formulation problems may possibly be overcome by modification of particle size and morphology. The application of power ultrasound is a novel possibility in drug formulation. This article reports on solvent diffusion and melt emulsification, as new methods supplemented with drying in the field of sonocrystallization of poorly water-soluble Gemfibrozil. During thermoanalytical characterization, a modified structure was detected. The specific surface area of the drug was increased following particle size reduction and the poor wettability properties could also be improved. The dissolution rate was therefore significantly increased. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Lumbar myelography using water-soluble contrast media

    International Nuclear Information System (INIS)

    Langlotz, M.

    1981-01-01

    With the new water-soluble contrast media developed in the last 10 years, lumbar myelography has become a simple and low-risk diagnostic method of great value which is hardly ever omitted before surgery is undertaken. The book attempts a synopsis of radiology and clinical examinations. In its first part, the pathological, clinical, and radiological aspects of diseases of the lumbosacral spinal duct are reviewed. The second part contains more than 300 myelographic pictures in original size. Each of the myelograms is supplemented by the case history of the patient (anamnesis, neurological examination, therapy and course). Interpretation is facilitated by drawings at the beginning of each chapter which show the major pathological and radiological changes. (orig./MG) [de

  5. Preparation of water soluble chitosan by hydrolysis using hydrogen peroxide.

    Science.gov (United States)

    Xia, Zhenqiang; Wu, Shengjun; Chen, Jinhua

    2013-08-01

    Chitosan is not soluble in water, which limits its wide application particularly in the medicine and food industry. In the present study, water soluble chitosan (WSC) was prepared by hydrolyzing chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid in homogeneous phase. Factors affecting hydrolysis were investigated and the optimal hydrolysis conditions were determined. The WSC structure was characterized by Fourier transform infrared spectroscopy. The resulting products were composed of chitooligosaccharides of DP 2-9. The WSC content of the product and the yield were 94.7% and 92.3% (w/w), respectively. The results indicate that WSC can be effectively prepared by hydrolysis of chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Facile synthesis of water-soluble curcumin nanocrystals

    Directory of Open Access Journals (Sweden)

    Marković Zoran M.

    2015-01-01

    Full Text Available In this paper, facile synthesis of water soluble curcumin nanocrystals is reported. Solvent exchange method was applied to synthesize curcumin nanocrystals. Different techniques were used to characterize the structural and photophysical properties of curcumin nanocrystals. We found that nanocurcumin prepared by this method had good chemical and physical stability, could be stored in the powder form at room temperature, and was freely dispersible in water. It was established that the size of curcumin nanocrystals was varied in the range of 20-500 nm. Fourier transform infrared spectroscopy and UV-Vis analyses showed the presence of tetrahydrofuran inside the curcumin nanocrystals. Also, it was found that nanocurcumin emitted photoluminescencewith yellow-green colour. [Projekat Ministarstva nauke Republike Srbije, br. 172003

  7. Novel water-soluble curcumin derivative mediating erectile signaling.

    Science.gov (United States)

    Abdel Aziz, Mohamed Talaat; El Asmer, Mohammed F; Rezq, Ameen; Kumosani, Taha Abdullah; Mostafa, Samya; Mostafa, Taymour; Atta, Hazem; Abdel Aziz Wassef, Mohamed; Fouad, Hanan H; Rashed, Laila; Sabry, Dina; Hassouna, Amira A; Senbel, Amira; Abdel Aziz, Ahmed

    2010-08-01

    Curcumin is an inducer of heme oxygenase enzyme-1 (HO-1) that is involved in erectile signaling via elevating cyclic guanosine monophosphate (cGMP)levels. To assess the effect of oral administration of a water-soluble long-acting curcumin derivative on erectile signaling. Two hundred and thirty six male white albino rats were divided into four groups; group 1 (N = 20) includes control. Group 2 (N = 72) was equally divided into four subgroups; subgroup 1 received pure curcumin (10 mg/kg), subgroup 2 received the long-acting curcumin derivative (2 mg/kg), subgroup 3 received the long-acting curcumin derivative (10 mg/kg), and subgroup 4 received sildenafil (4 mg/kg). Subgroups were sacrificed after the first, second, and third hour. Group 3 (N = 72) was equally divided into the same four subgroups already mentioned and were sacrificed after 24 hours, 48 hours, and 1 week. Group 4 (N = 72) was subjected to intracavernosal pressure (ICP) measurements 1 hour following oral administration of the same previous doses in the same rat subgroups. Cavernous tissue HO enzyme activity, cGMP, and ICP. In group 2, there was a significant progressive maintained elevation of HO activity and cGMP tissue levels starting from the first hour in subgroups 3 and 4, whereas, the rise in HO activity and cGMP started from second hour regarding the other rat subgroups. Sildenafil effect decreased after 3 hours. In group 3, there was a significant maintained elevation of HO activity and cGMP tissue levels extended to 1 week as compared to controls for all rat subgroups that received both forms of curcumin. In group 4, long-acting curcumin derivative exhibited more significant potentiation of intracavernosal pressure as compared to control and to the pure curcumin. Water-soluble long-acting curcumin derivative could mediate erectile function via upregulating cavernous tissue cGMP. © 2009 International Society for Sexual Medicine.

  8. Spectrofluorimetric determination of some water-soluble vitamins.

    Science.gov (United States)

    Mohamed, Abdel-Maaboud I; Mohamed, Horria A; Abdel-Latif, Niveen M; Mohamed, Marwa R

    2011-01-01

    Two simple and sensitive spectrofluorimetric methods were developed for determination of three water-soluble vitamins (B1, B2, and B6) in mixtures in the presence of cyanocobalamin. The first one was for thiamine determination, which depends on the oxidation of thiamine HCl to thiochrome by iodine in an alkaline medium. The method was applied accurately to determine thiamine in binary, ternary, and quaternary mixtures with pyridoxine HCl, riboflavin, and cyanocobalamin without interference. In the second method, riboflavin and pyridoxine HCl were determined fluorimetrically in acetate buffer, pH 6. The three water-soluble vitamins (B1, B2, and B6) were determined spectrofluorimetrically in binary, ternary, and quaternary mixtures in the presence of cyanocobalamin. All variables were studied in order to optimize the reaction conditions. Linear relationship was obeyed for all studied vitamins by the proposed methods at their corresponding lambda(exc) or lambda(em). The linear calibration curves were obtained from 10 to 500 ng/mL; the correlation ranged from 0.9991 to 0.9999. The suggested procedures were applied to the analysis of the investigated vitamins in their laboratory-prepared mixtures and pharmaceutical dosage forms from different manufacturers. The RSD range was 0.46-1.02%, which indicates good precision. No interference was observed from common pharmaceutical additives. Good recoveries (97.6 +/- 0.7-101.2 +/- 0.8%) were obtained. Statistical comparison of the results with reported methods shows excellent agreement and indicates no significant difference in accuracy and precision.

  9. Synthesis and self-assembling of responsive polysaccharide-based copolymers in aqueous media

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Nivia do N.; Balaban, Rosangela de C. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Halila, Sami; Borsali, Redouane, E-mail: borsali@cermav.cnrs.fr, E-mail: halila@cermav.cnrs.fr [Centre de Recherche sur les Macromolecules Vegetales (CERMAV), Grenoble (France)

    2015-07-01

    This work reports the synthesis and the thermoresponsive self-assembly behavior of carboxymethylcellulose-g-JeffamineM2070 and carboxymethylcellulose-g-JeffamineM600 copolymers in aqueous media. They were prepared through the grafting of two different types of amino-terminated poly(ethylene oxide-co-propylene oxide) chains onto the carboxylate groups of carboxymethylcellulose, by using water-soluble carbodiimide derivative and N-hydroxysuccinimide as coupling reagents. The grafting efficiency was confirmed by infrared and the degree of substitution by {sup 1}H NMR integrations. The salt effect on cloud point temperature was evaluated into different solvents (Milli-Q water, 0.5M NaCl, synthetic sea water (SSW) and 0.5M K{sub 2}CO{sub 3}) by UV-Vis and dynamic light scattering (DLS) measurements. Both copolymers showed lower cloud point temperature in 0.5M K2CO3 than in 0.5M NaCl and in SSW, which was attributed to the higher ionic strength for K{sub 2}CO{sub 3} combined to the ability of CO{sub 3}{sup 2-} to decrease polymer-water interactions. Copolymers chains displayed higher hydrodynamic radii than CMC precursor at 25 and 60 °C in saline solutions, and self-associations changed as a function of the environment and copolymer composition. (author)

  10. Synthesis and self-assembling of responsive polysaccharide-based copolymers in aqueous media

    International Nuclear Information System (INIS)

    Marques, Nivia do N.; Balaban, Rosangela de C.; Halila, Sami; Borsali, Redouane

    2015-01-01

    This work reports the synthesis and the thermoresponsive self-assembly behavior of carboxymethylcellulose-g-JeffamineM2070 and carboxymethylcellulose-g-JeffamineM600 copolymers in aqueous media. They were prepared through the grafting of two different types of amino-terminated poly(ethylene oxide-co-propylene oxide) chains onto the carboxylate groups of carboxymethylcellulose, by using water-soluble carbodiimide derivative and N-hydroxysuccinimide as coupling reagents. The grafting efficiency was confirmed by infrared and the degree of substitution by "1H NMR integrations. The salt effect on cloud point temperature was evaluated into different solvents (Milli-Q water, 0.5M NaCl, synthetic sea water (SSW) and 0.5M K_2CO_3) by UV-Vis and dynamic light scattering (DLS) measurements. Both copolymers showed lower cloud point temperature in 0.5M K2CO3 than in 0.5M NaCl and in SSW, which was attributed to the higher ionic strength for K_2CO_3 combined to the ability of CO_3"2"- to decrease polymer-water interactions. Copolymers chains displayed higher hydrodynamic radii than CMC precursor at 25 and 60 °C in saline solutions, and self-associations changed as a function of the environment and copolymer composition. (author)

  11. Water-soluble elements in atmospheric particulate matter over tropical and equatorial Atlantic

    International Nuclear Information System (INIS)

    Buat-Menard, Patrick; Morelli, Jacques; Chesselet, Roger

    1974-01-01

    Samples of water-soluble atmospheric particulate matter collected from R/V ''Jean Charcot'' (May to October 1971) and R/V ''James Gilliss'' (October 1972) over Tropical and Equatorial Atlantic were analyzed for Na, Mg, K and Ca by atomic absorption and for Cl and S as SO 4 by colorimetry. Data shows a strong geographical dependence of K and Ca enrichment relative to their elemental ratio to Na in sea-water. Ca enrichment is related to presence of identified soluble calcium minerals in continental dust originating from African deserts (Sahara-Kalahari). This dust does not influence amounts of K in the water-soluble phase. When observed, strong K enrichment appears tightly associated with high concentrations of surface-active organic material in the microlayer derived from high biological activity (Gulf of Guinea). Observed in same samples, SO 4 enrichment could also be controlled by the same source. This SO 4 enrichment balances the observed Cl loss in aerosols accordingly with gaseous HCl formation processes in marine atmosphere [fr

  12. Water soluble bioactives of nacre mediate antioxidant activity and osteoblast differentiation.

    Directory of Open Access Journals (Sweden)

    Ratna Chaturvedi

    Full Text Available The water soluble matrix of nacre is a proven osteoinductive material. In spite of the differences in the biomolecular compositions of nacre obtained from multiple species of oysters, the common biochemical properties of those principles substantiate their biological activity. However, the mechanism by which nacre stimulates bone differentiation remains largely unknown. Since the positive impact of antioxidants on bone metabolism is well acknowledged, in this study we investigated the antioxidant potential of a water soluble matrix (WSM obtained from the nacre of the marine oyster Pinctada fucata, which could regulate its osteoblast differentiation activity. Enhanced levels of ALP activity observed in pre-osteoblast cells upon treatment with WSM, suggested the induction of bone differentiation events. Furthermore, bone nodule formation and up-regulation of bone differentiation marker transcripts, i.e. collagen type-1 and osteocalcin by WSM confirmed its ability to induce differentiation of the pre-osteoblasts into mature osteoblasts. Remarkably, same WSM fraction upon pre-treatment lowered the H2O2 and UV-B induced oxidative damages in keratinocytes, thus indicating the antioxidant potential of WSM. This was further confirmed from the in vitro scavenging of ABTS and DPPH free radicals and inhibition of lipid peroxidation by WSM. Together, these results indicate that WSM poses both antioxidant potential and osteoblast differentiation property. Thus, bioactivities associated with nacre holds potential in the development of therapeutics for bone regeneration and against oxidative stress induced damages in cells.

  13. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].

    Science.gov (United States)

    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming

    2015-06-01

    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane.

  14. Impact of fog processing on water soluble organic aerosols.

    Science.gov (United States)

    Tripathi, S. N.; Chakraborty, A.; Gupta, T.

    2017-12-01

    Fog is a natural meteorological phenomenon that occurs all around the world, and contains a substantial quantity of liquid water. Fog is generally seen as a natural cleansing agent but can also form secondary organic aerosols (SOA) via aqueous processing of ambient organics. Few field studies have reported elevated O/C ratio and SOA mass during or after fog events. However, mechanism behind aqueous SOA formation and its contribution to total organic aerosols (OA) still remains unclear. In this study we have tried to explore the impact of fog/aqueous processing on the characteristics of water soluble organic aerosols (WSOC), which to our knowledge has not been studied before. To assess this, both online (using HR-ToF-AMS) and offline (using a medium volume PM2.5 sampler and quartz filter) aerosol sampling were carried out at Kanpur, India from 15 December 2014 - 10 February 2015. Further, offline analysis of the aqueous extracts of the collected filters were carried out by AMS to characterize the water soluble OA (WSOA). Several (17) fog events occurred during the campaign and high concentrations of OA (151 ± 68 µg/m3) and WSOA (47 ± 19 µg/m3) were observed. WSOA/OA ratios were similar during fog (0.36 ± 0.14) and nofog (0.34 ± 0.15) periods. WSOA concentrations were also similar (slightly higher) during foggy (49 ± 18 µg/m3) and non-foggy periods (46 ± 20 µg/m3), in spite of fog scavenging. However, WSOA was more oxidized during foggy period (average O/C = 0.81) than non foggy periods (average O/C = 0.70). Like WSOA, OA was also more oxidized during foggy periods (average O/C = 0.64) than non foggy periods (average O/C = 0.53). During fog, WSOA to WIOA (water insoluble OA) ratios were higher (0.65 ± 0.16) compared to non foggy periods (0.56 ± 0.15). These observations clearly showed that WSOA become more dominant and processed during fog events, possibly due to the presence of fog droplets. This study highlights that fog processing of soluble organics

  15. Novel Water Soluble Chitosan Derivatives with 1,2,3-Triazolium and Their Free Radical-Scavenging Activity.

    Science.gov (United States)

    Li, Qing; Sun, Xueqi; Gu, Guodong; Guo, Zhanyong

    2018-03-28

    Chitosan is an abundant and renewable polysaccharide, which exhibits attractive bioactivities and natural properties. Improvement such as chemical modification of chitosan is often performed for its potential of providing high bioactivity and good water solubility. A new class of chitosan derivatives possessing 1,2,3-triazolium charged units by associating "click reaction" with efficient 1,2,3-triazole quaternization were designed and synthesized. Their free radical-scavenging activity against three free radicals was tested. The inhibitory property and water solubility of the synthesized chitosan derivatives exhibited a remarkable improvement over chitosan. It is hypothesized that triazole or triazolium groups enable the synthesized chitosan to possess obviously better radical-scavenging activity. Moreover, the scavenging activity against superoxide radical of chitosan derivatives with triazolium (IC 50 radical-scavenging assay, the same pattern were observed, which should be related to the triazolium grafted at the periphery of molecular chains.

  16. Biological properties of water-soluble phosphorhydrazone dendrimers

    Directory of Open Access Journals (Sweden)

    Anne-Marie Caminade

    2013-01-01

    Full Text Available Dendrimers are hyperbranched and perfectly defined macromolecules, constituted of branches emanating from a central core in an iterative fashion. Phosphorhydrazone dendrimers constitute a special family of dendrimers, possessing one phosphorus atom at each branching point. The internal structure of these dendrimers is hydrophobic, but hydrophilic terminal groups can induce the solubility of the whole structure in water. Indeed, the properties of these compounds are mainly driven by the type of terminal groups their bear; this is especially true for the biological properties. For instance, positively charged terminal groups are efficient for transfection experiments, as drug carriers, as anti-prion agents, and as inhibitor of the aggregation of Alzheimer's peptides, whereas negatively charged dendrimers have anti-HIV properties and can influence the human immune system, leading to anti-inflammatory properties usable against rheumatoid arthritis. This review will give the most representative examples of the biological properties of water-soluble phosphorhydrazone dendrimers, organized depending on the type of terminal groups they bear.

  17. Water-soluble resist for environmentally friendly lithography

    Science.gov (United States)

    Lin, Qinghuang; Simpson, Logan L.; Steinhaeusler, Thomas; Wilder, Michelle; Willson, C. Grant; Havard, Jennifer M.; Frechet, Jean M. J.

    1996-05-01

    This paper describes an 'environmentally friendly,' water castable, water developable photoresist system. The chemically amplified negative-tone resist system consists of three water-soluble components: a polymer, poly(methyl acrylamidoglycolate methyl ether), [poly(MAGME)]; a photoacid generator, dimethyl dihydroxyphenylsulfonium triflate and a crosslinker, butanediol. Poly(MAGME) was synthesized by solution free radical polymerization. In the three-component resist system, the acid generated by photolysis of the photoacid generator catalyzes the crosslinking of poly(MAGME) in the exposed regions during post-exposure baking, thus rendering the exposed regions insoluble in water. Negative tone relief images are obtained by developing with pure water. The resist is able to resolve 1 micrometer line/space features (1:1 aspect ratio) with an exposure dose of 100 mJ/cm2 at 248 nm. The resist can be used to generate etched copper relief images on printed circuit boards using aqueous sodium persulfate as the etchant. The crosslinking mechanism has been investigated by model compound studies using 13C NMR. These studies have revealed that the acid catalyzed reaction of the poly(MAGME) with butanediol proceeds via both transesterification and transacetalization (transaminalization) reactions at low temperatures, and also via transamidation at high temperatures.

  18. Water Soluble Polymers as Proton Exchange Membranes for Fuel Cells

    Directory of Open Access Journals (Sweden)

    Bing-Joe Hwang

    2012-03-01

    Full Text Available The relentless increase in the demand for useable power from energy-hungry economies continues to drive energy-material related research. Fuel cells, as a future potential power source that provide clean-at-the-point-of-use power offer many advantages such as high efficiency, high energy density, quiet operation, and environmental friendliness. Critical to the operation of the fuel cell is the proton exchange membrane (polymer electrolyte membrane responsible for internal proton transport from the anode to the cathode. PEMs have the following requirements: high protonic conductivity, low electronic conductivity, impermeability to fuel gas or liquid, good mechanical toughness in both the dry and hydrated states, and high oxidative and hydrolytic stability in the actual fuel cell environment. Water soluble polymers represent an immensely diverse class of polymers. In this comprehensive review the initial focus is on those members of this group that have attracted publication interest, principally: chitosan, poly (ethylene glycol, poly (vinyl alcohol, poly (vinylpyrrolidone, poly (2-acrylamido-2-methyl-1-propanesulfonic acid and poly (styrene sulfonic acid. The paper then considers in detail the relationship of structure to functionality in the context of polymer blends and polymer based networks together with the effects of membrane crosslinking on IPN and semi IPN architectures. This is followed by a review of pore-filling and other impregnation approaches. Throughout the paper detailed numerical results are given for comparison to today’s state-of-the-art Nafion® based materials.

  19. Carcinogenicity assessment of water-soluble nickel compounds.

    Science.gov (United States)

    Goodman, Julie E; Prueitt, Robyn L; Dodge, David G; Thakali, Sagar

    2009-01-01

    IARC is reassessing the human carcinogenicity of nickel compounds in 2009. To address the inconsistencies among results from studies of water-soluble nickel compounds, we conducted a weight-of-evidence analysis of the relevant epidemiological, toxicological, and carcinogenic mode-of-action data. We found the epidemiological evidence to be limited, in that some, but not all, data suggest that exposure to soluble nickel compounds leads to increased cancer risk in the presence of certain forms of insoluble nickel. Although there is no evidence that soluble nickel acts as a complete carcinogen in animals, there is limited evidence that suggests it may act as a tumor promoter. The mode-of-action data suggest that soluble nickel compounds will not be able to cause genotoxic effects in vivo because they cannot deliver sufficient nickel ions to nuclear sites of target cells. Although the mode-of-action data suggest several possible non-genotoxic effects of the nickel ion, it is unclear whether soluble nickel compounds can elicit these effects in vivo or whether these effects, if elicited, would result in tumor promotion. The mode-of-action data equally support soluble nickel as a promoter or as not being a causal factor in carcinogenesis at all. The weight of evidence does not indicate that soluble nickel compounds are complete carcinogens, and there is only limited evidence that they could act as tumor promoters.

  20. Aerobic Biodegradation Characteristic of Different Water-Soluble Azo Dyes

    Directory of Open Access Journals (Sweden)

    Shixiong Sheng

    2017-12-01

    Full Text Available This study investigated the biodegradation performance and characteristics of Sudan I and Acid Orange 7 (AO7 to improve the biological dye removal efficiency in wastewater and optimize the treatment process. The dyes with different water-solubility and similar molecular structure were biologically treated under aerobic condition in parallel continuous-flow mixed stirred reactors. The biophase analysis using microscopic examination suggested that the removal process of the two azo dyes is different. Removal of Sudan I was through biosorption, since it easily assembled and adsorbed on the surface of zoogloea due to its insolubility, while AO7 was biodegraded incompletely and bioconverted, the AO7 molecule was decomposed to benzene series and inorganic ions, since it could reach the interior area of zoogloea due to the low oxidation-reduction potential conditions and corresponding anaerobic microorganisms. The transformation of NH3-N, SO42− together with the presence of tryptophan-like components confirm that AO7 can be decomposed to non-toxic products in an aerobic bioreactor. This study provides a theoretical basis for the use of biosorption or biodegradation mechanisms for the treatment of different azo dyes in wastewater.

  1. Monosaccharides as Versatile Units for Water-Soluble Supramolecular Polymers.

    Science.gov (United States)

    Leenders, Christianus M A; Jansen, Gijs; Frissen, Martijn M M; Lafleur, René P M; Voets, Ilja K; Palmans, Anja R A; Meijer, E W

    2016-03-18

    We introduce monosaccharides as versatile water-soluble units to compatibilise supramolecular polymers based on the benzene-1,3,5-tricarboxamide (BTA) moiety with water. A library of monosaccharide-based BTAs is evaluated, varying the length of the alkyl chain (hexyl, octyl, decyl and dodecyl) separating the BTA and saccharide units, as well as the saccharide units (α-glucose, β-glucose, α-mannose and α-galactose). In all cases, the monosaccharides impart excellent water compatibility. The length of the alkyl chain is the determining factor to obtain either long, one-dimensional supramolecular polymers (dodecyl spacer), small aggregates (decyl spacer) or molecularly dissolved (octyl and hexyl) BTAs in water. For the BTAs comprising a dodecyl spacer, our results suggest that a cooperative self-assembly process is operative and that the introduction of different monosaccharides does not significantly change the self- assembly behaviour. Finally, we investigate the potential of post-assembly functionalisation of the formed supramolecular polymers by taking advantage of dynamic covalent bond formation between the monosaccharides and benzoxaboroles. We observe that the supramolecular polymers readily react with a fluorescent benzoxaborole derivative permitting imaging of these dynamic complexes by confocal fluorescence microscopy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. OCTANOL/WATER PARTITION COEFFICIENTS AND WATER SOLUBILITIES OF PHTHALATE ESTERS

    Science.gov (United States)

    Measurements of the octanol/water partition coefficients (K-ow) and water solubilities of di-n-octyl phthalate (DnOP) and di-n-decyl phthalate (DnDP) by the slow-stirring method are reported. The water solubility was also measured for di-n-hexyl phthalate (DnHP). The log K-ow val...

  3. Process for the production of furfural from pentoses and/or water soluble pentosans

    NARCIS (Netherlands)

    De Jong, W.; Marcotullio, G.

    2012-01-01

    The invention is directed to a process for the production of furfural from pentoses and/or water soluble pentosans, said process comprising converting the said pentoses and/or water soluble pentosans in aqueous solution in a first step to furfural and in a second step feeding the aqueous solution

  4. Analyzing water soluble soil organics as Trifluoroacetyl derivatives by liquid state proton nuclear magnetic resonance

    Science.gov (United States)

    Felipe Garza Sanchez; Zakiya Holmes Leggett; Sabapathy Sankar

    2005-01-01

    In forested ecosystems, water soluble organics play an important role in soil processes including carbon and nutrient turnover, microbial activity and pedogenesis. The quantity and quality (i.e., chemistry) of these materials is sensitive to land management practices. Monitoring alterations in the chemistry of water soluble organics resulting from land management...

  5. Study on spraying water soluble resin to reduce pollution for Fukushima daiichi NPP accident

    International Nuclear Information System (INIS)

    Zhang Qiong; Guo Ruiping; Zhang Chunming; Han Fujuan; Hua Jie; Zhang Jiankui

    2012-01-01

    After Fukushima nuclear accident, Tokyo electric power company used the method of spraying water soluble resin synthesis at the scene of the accident, to restrain and control the spread of the radioactive dust, by forming consolidation layer in pollution area surface. This paper briefly introduced the accident, motivation of spraying water soluble resin, spraying range and implementation process. According to the relevant report on Fukushima nuclear accident, the effect of spraying water soluble resin for reducing pollution was analyzed. The mechanism of reducing pollution for water soluble resin and the application prospect were discussed. Spraying water soluble resin for fixing radioactive dust has reasonable reducing pollution effect. It is worth to use as reference and study in China. (authors)

  6. Antibacterial Characteristics and Activity of Water-Soluble Chitosan Derivatives Prepared by the Maillard Reaction

    Directory of Open Access Journals (Sweden)

    Ying-Chien Chung

    2011-10-01

    Full Text Available The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. In addition, it was found that the susceptibility of the test organisms to the water-soluble chitosan derivative was higher in deionized water than in saline solution. Metal ions were also found to reduce the antibacterial activity of the water-soluble chitosan derivative on S. aureus. The marked increase in glucose level, protein content and lactate dehydrogenase (LDH activity was observed in the cell supernatant of S. aureus exposed to the water-soluble chitosan derivative in deionized water. The results suggest that the water-soluble chitosan produced by Maillard reaction may be a promising commercial substitute for acid-soluble chitosan.

  7. Sulfomethylated graft copolymers of xanthan gum and polyacrylamide

    Energy Technology Data Exchange (ETDEWEB)

    Cottrell, I.W.; Empey, R.A.; Racciato, J.S.

    1978-08-08

    A water-soluble anionic graft copolymer of xanthan gum and polyacrylamide is described in which at least part of the amide function of the acrylamide portion of the copolymer is sulfomethylated and the xanthan gum portion of the copolymer is unreacted with formaldehyde. The copolymer is sulfomethylated by reaction with formaldehyde and sodium metabisulfite. The formaldehyde does not cause any appreciable cross-linking between hydroxyl groups of the xanthan moieties. The sulfomethylation of the acrylamido group takes place at temperatures from 35 to 70 C. The pH is 10 or higher, typically from 12 to 13. The degree of anionic character may be varied by adjusting the molar ratio of formaldehyde and sodium metabisulfite with respect to the copolymer. 10 claims.

  8. Utilization of water soluble plastics for radiological control within nuclear power plants

    International Nuclear Information System (INIS)

    Smith, R.J.; Deltete, C.P.; Homyk, W.A.; Kasprzak, L.; Robinson, P.J.

    1989-01-01

    The utilization of plastic products for radioactive contamination control within nuclear power facilities currently results in relatively large volumes of waste requiring disposal as low-level radioactive waste. The utilization of a polymer resin product that possesses comparable physical attributes to currently utilized plastic materials, but which is water soluble, has significant potential to reduce the volume of plastic waste requiring disposal as radwaste. Such a volume reduction will reduce overall plant )ampersand M costs, reduce the overall waste volume allocation utilization, and improve the regulatory perception of any plant realizing a volume reduction through plastic source minimization. This potential reduction in waste volume (and associated availability of the Low-level Waste Policy Amendments Act disposal allocation for other purposes), combined with potential economic benefits summarized above, has led to the undertaking of a detailed evaluation, presented in this paper

  9. Diseño y validación de un nuevo método para estimar reductores hidrosolubles asociados con la quitina Design and validation of a new method for estimation of water-soluble reducers associated with chitin

    Directory of Open Access Journals (Sweden)

    Yania Suárez Pérez

    2005-12-01

    Full Text Available Se desarrolló por primera vez un método espectrofotométrico para estimar reductores hidrosolubles asociados con la quitina materia prima. Para el ajuste del método se utilizó glucosamina como sustancia de referencia. Las determinaciones se realizaron a 330 nm que fue la longitud de onda de máxima absorción. Se seleccionó como tiempo óptimo de calentamiento 5 min y se verificó la selectividad de la respuesta analítica. Se demostró el cumplimiento de la ley de Lambert-Beer en el intervalo de 100-300 mg/mL. Se obtuvo un extracto acuoso a partir de quitina materia prima procesado para eliminar posibles interferencias, el cual se empleó como control en la validación del método. El método fue lineal, exacto y preciso en el intervalo estudiado. El límite de detección fue de 25,21 mg/mL y el de cuantificación de 65,45 mg/mL.For the first time, a spectrophotometric method to estimate water-soluble reducers associated with raw material chitin was developed. For the purpose of adjusting the method, glucosamine as a reference substance was used. The estimations were made at 330 nm that was the wavelength of maximum absorption. The selected optimal heating time was 5 min; the selectivity of analytical response was checked. The Lambert-Beer law was demonstrated in the 100-300 mg/mL interval. An aqueous extract from raw material chitin was obtained and then processed to eliminate possible interference and be used as a control for the method validation. The method was linear, exact and accurate in the studied interval. The detection limit was 25,21 mg/mL and the quantification limit was 65,45 mg/mL.

  10. Electrochemical detection of dopamine using water-soluble sulfonated graphene

    International Nuclear Information System (INIS)

    Li, Su-Juan; He, Jun-Zhi; Zhang, Meng-Jie; Zhang, Rong-Xia; Lv, Xia-Lei; Li, Shao-Hua; Pang, Huan

    2013-01-01

    Graphical abstract: DPV responses of dopamine (DA) at sulfonated graphene based glassy carbon electrode in the presence of ascorbic acid (AA) and uric acid (UA). The separation of the oxidation peak potentials for AA-DA, DA-UA and UA-AA was about 227 mV, 125 mV and 352 mV, which allowed selectively determining DA. -- Abstract: In the present study, a biosensor was prepared using the water-soluble sulfonated graphene with the aim of achieving the selective and sensitive determination of dopamine (DA) in the presence of ascorbic acid (AA) and uric acid (UA). The aromatic π–π stacking and electrostatic attraction between positively charged DA and negatively charged sulfonated graphene can accelerate the electron transfer whereas weakening AA and UA oxidation on the sulfonated graphene-modified electrode. Fourier transform infrared spectra (FTIR), energy dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to characterize the successful synthesis of sulfonated graphene sheets. Differential pulse voltammetry was used for electrochemical detection, the separation of the oxidation peak potentials for AA-DA, DA-UA and UA-AA was about 227 mV, 125 mV and 352 mV, which allowed selectively determining DA. A broad linear range, low detection limit, along with good ability to suppress the background current from large excess ascorbic acid (AA) and uric acid (UA) were obtained. The as-prepared sulfonated graphene sheets exhibited superior performance over conventional negatively charged Nafion films, such as flexible film thickness, unique nanostructure, excellent anti-interference ability, high sensitivity and selectivity. The proposed method was used to detect DA in real hydrochloride injection sample, human urine and serum samples with satisfactory recovery results

  11. Water soluble vitamin E (TMG) as a radioprotector.

    Science.gov (United States)

    Nair, Cherupally Krishnan K; Devi, Pathirissery Uma; Shimanskaya, R; Kunugita, N; Murase, Hironobu; Gu, Yeun-Hwa; Kagiya, Tsutomu V

    2003-12-01

    Tocopherol monoglucoside (TMG), a water soluble derivative of vitamin E offers protection against deleterious effects of ionizing radiation, both under in vivo and in vitro conditions, to biological systems. TMG was found to be a potent antioxidant and an effective free radical scavenger. It forms a phenoxyl radical similar to trolox upon reaction with various one-electron oxidants. TMG protected DNA from radiation-induced strand breaks. It also protected thymine glycol formation induced by gamma-radiation. Gamma-radiation-induced loss of viability of EL-tumor cells and peroxidation of lipids in microsomal and mitochondrial membranes were prevented by TMG. TMG was nontoxic to mice when administered orally up to 7.0 g/kg body weight. The LD50 dose of TMG for ip administration in mice was 1.15 g/kg body wt. In rats, following oral and ip administration of TMG, the absorption (distribution) half lives were 5.8 and 3.0 min respectively and elimination half lives were 6.7 and 3.1 min respectively. Embryonic mortality resulting from exposure of pregnant mice to ionizing radiation (2 Gy) was reduced by 75% by ip administration of TMG (0.6 g/kg, body wt) prior to irradiation. TMG offered protection to mice against whole body gamma-radiation-induced lethality and weight loss. The LD50(30) of mice increased from 6 to 6.72 Gy upon post irradiation administration of a single dose of TMG (0.6 g/kg, body wt) by ip.

  12. Determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of water-soluble tetrazolium salts.

    Science.gov (United States)

    Tsukatani, Tadayuki; Suenaga, Hikaru; Ishiyama, Munetaka; Ezoe, Takatoshi; Matsumoto, Kiyoshi

    2011-07-15

    A method for the determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of the tetrazolium salt {2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8)} via 2-methyl-1,4-napthoquinone (NQ) was developed. Measurement conditions were optimized for the microbiological determination of water-soluble vitamins, such as vitamin B(6), biotin, folic acid, niacin, and pantothenic acid, using microorganisms that have a water-soluble vitamin requirement. A linear relationship between absorbance and water-soluble vitamin concentration was obtained. The proposed method was applied to determine the concentration of vitamin B(6) in various foodstuffs. There was good agreement between vitamin B(6) concentrations determined after 24h using the WST-8 colorimetric method and those obtained after 48h using a conventional method. The results suggest that the WST-8 colorimetric assay is a useful method for the rapid determination of water-soluble vitamins in a 96-well microtiter plate. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Aqueous dispersion polymerization: a new paradigm for in situ block copolymer self-assembly in concentrated solution.

    Science.gov (United States)

    Sugihara, Shinji; Blanazs, Adam; Armes, Steven P; Ryan, Anthony J; Lewis, Andrew L

    2011-10-05

    Reversible addition-fragmentation chain transfer polymerization has been utilized to polymerize 2-hydroxypropyl methacrylate (HPMA) using a water-soluble macromolecular chain transfer agent based on poly(2-(methacryloyloxy)ethylphosphorylcholine) (PMPC). A detailed phase diagram has been elucidated for this aqueous dispersion polymerization formulation that reliably predicts the precise block compositions associated with well-defined particle morphologies (i.e., pure phases). Unlike the ad hoc approaches described in the literature, this strategy enables the facile, efficient, and reproducible preparation of diblock copolymer spheres, worms, or vesicles directly in concentrated aqueous solution. Chain extension of the highly hydrated zwitterionic PMPC block with HPMA in water at 70 °C produces a hydrophobic poly(2-hydroxypropyl methacrylate) (PHPMA) block, which drives in situ self-assembly to form well-defined diblock copolymer spheres, worms, or vesicles. The final particle morphology obtained at full monomer conversion is dictated by (i) the target degree of polymerization of the PHPMA block and (ii) the total solids concentration at which the HPMA polymerization is conducted. Moreover, if the targeted diblock copolymer composition corresponds to vesicle phase space at full monomer conversion, the in situ particle morphology evolves from spheres to worms to vesicles during the in situ polymerization of HPMA. In the case of PMPC(25)-PHPMA(400) particles, this systematic approach allows the direct, reproducible, and highly efficient preparation of either block copolymer vesicles at up to 25% solids or well-defined worms at 16-25% solids in aqueous solution.

  14. Formulation of a poorly water-soluble drug in sustained-release hollow granules with a high viscosity water-soluble polymer using a fluidized bed rotor granulator.

    Science.gov (United States)

    Asada, Takumi; Yoshihara, Naoki; Ochiai, Yasushi; Kimura, Shin-Ichiro; Iwao, Yasunori; Itai, Shigeru

    2018-04-25

    Water-soluble polymers with high viscosity are frequently used in the design of sustained-release formulations of poorly water-soluble drugs to enable complete release of the drug in the gastrointestinal tract. Tablets containing matrix granules with a water-soluble polymer are preferred because tablets are easier to handle and the multiple drug-release units of the matrix granules decreases the influences of the physiological environment on the drug. However, matrix granules with a particle size of over 800 μm sometimes cause a content uniformity problem in the tableting process because of the large particle size. An effective method of manufacturing controlled-release matrix granules with a smaller particle size is desired. The aim of this study was to develop tablets containing matrix granules with a smaller size and good controlled-release properties, using phenytoin as a model poorly water-soluble drug. We adapted the recently developed hollow spherical granule granulation technology, using water-soluble polymers with different viscosities. The prepared granules had an average particle size of 300 μm and sharp particle size distribution (relative width: 0.52-0.64). The values for the particle strength of the granules were 1.86-1.97 N/mm 2 , and the dissolution profiles of the granules were not affected by the tableting process. The dissolution profiles and the blood concentration levels of drug released from the granules depended on the viscosity of the polymer contained in the granules. We succeeded in developing the desired controlled-release granules, and this study should be valuable in the development of sustained-release formulations of poorly water-soluble drugs. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Predicting water solubility of congeners: Chloronaphthalenes-A case study

    Energy Technology Data Exchange (ETDEWEB)

    Puzyn, Tomasz, E-mail: puzi@qsar.eu.org [Faculty of Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Mostrag, Aleksandra; Falandysz, Jerzy [Faculty of Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Kholod, Yana; Leszczynski, Jerzy [NSF CREST Nanotoxicity Center, Department of Chemistry, Jackson State University, 1325 Lynch St, Jackson, MS 39217-0510 (United States)

    2009-10-30

    Since the important physicochemical data for chloronaphtalenes (PCNs) are still scarce, we have predicted water solubility (log S) of all 75 congeners with the Quantitative Structure-Property Relationship (QSPR) scheme. The values of log S, predicted by the most efficient model, varied from 0.01 to 1660 {mu}g dm{sup -3} (2.85 x 10{sup -11}-1.02 x 10{sup -5} mol dm{sup -3}), depending on the number of chlorine atoms present in the molecule and the substitution pattern. We found that the main factor determining relative differences in solubility between the congeners is the solvent accessible volume related to the cavitation process occurring in the solvent. The results are presented as a case study of QSPR modeling for those Persistent Organic Pollutants (POPs) that exist as families of congeners. By investigating the impact of (i) the way of the molecular descriptors' calculation, (ii) the size of applied database and (iii) chemometric method of modeling (Multiple Linear Regression, MLR, and/or Partial Least Squares regression, PLS) on the quality of the models we proposed general recommendations for dealing with congeners. We found that the combination of the B3LYP functional with 6-311++G(d,p) basis set was the most optimal technique of the molecular descriptors' calculation for congeners when comparing with semi-empirical PM3, ab initio Hartee-Fock (HF), and Moller-Pleset 2 (MP2) method carried out with different-size basis sets. Moreover, the model developed with a larger and more general database that includes chloronaphthalenes, polychlorinated dibezno-p-dioxins, furans and biphenyls predicted the values of log S for PCNs noticeable worse than the model calibrated only on PCNs. In the later case it was possible to obtain satisfactory results by employing even the simplest MLR method and only one molecular descriptor. The values of log S were also calculated with the WSKOWIN and COSMO-RS models as the reference techniques and then compared to our

  16. Predicting water solubility of congeners: Chloronaphthalenes-A case study

    International Nuclear Information System (INIS)

    Puzyn, Tomasz; Mostrag, Aleksandra; Falandysz, Jerzy; Kholod, Yana; Leszczynski, Jerzy

    2009-01-01

    Since the important physicochemical data for chloronaphtalenes (PCNs) are still scarce, we have predicted water solubility (log S) of all 75 congeners with the Quantitative Structure-Property Relationship (QSPR) scheme. The values of log S, predicted by the most efficient model, varied from 0.01 to 1660 μg dm -3 (2.85 x 10 -11 -1.02 x 10 -5 mol dm -3 ), depending on the number of chlorine atoms present in the molecule and the substitution pattern. We found that the main factor determining relative differences in solubility between the congeners is the solvent accessible volume related to the cavitation process occurring in the solvent. The results are presented as a case study of QSPR modeling for those Persistent Organic Pollutants (POPs) that exist as families of congeners. By investigating the impact of (i) the way of the molecular descriptors' calculation, (ii) the size of applied database and (iii) chemometric method of modeling (Multiple Linear Regression, MLR, and/or Partial Least Squares regression, PLS) on the quality of the models we proposed general recommendations for dealing with congeners. We found that the combination of the B3LYP functional with 6-311++G(d,p) basis set was the most optimal technique of the molecular descriptors' calculation for congeners when comparing with semi-empirical PM3, ab initio Hartee-Fock (HF), and Moller-Pleset 2 (MP2) method carried out with different-size basis sets. Moreover, the model developed with a larger and more general database that includes chloronaphthalenes, polychlorinated dibezno-p-dioxins, furans and biphenyls predicted the values of log S for PCNs noticeable worse than the model calibrated only on PCNs. In the later case it was possible to obtain satisfactory results by employing even the simplest MLR method and only one molecular descriptor. The values of log S were also calculated with the WSKOWIN and COSMO-RS models as the reference techniques and then compared to our results.

  17. Review: kinetics of water-soluble contrast media in the central nervous system

    International Nuclear Information System (INIS)

    Sage, M.R.

    1983-01-01

    In neuroradiology, intraarterial, intravenous, and intrathecal injections of water-soluble contrast media are made. With the growing importance of water-soluble myelography, interventional angiography, and enhanced computed tomography (CT), it is essential to have a clear understanding of the response of the nervous system to such procedures. The blood, cerebrospinal fluid (CSF), and extracellular fluid of the parenchyma form the fluid compartments of the brain with three interfaces between, namely, the blood-brain interface, the CSF-brain interface, and the blood-CSF interface. One of more of these interfaces are exposed to water-soluble contrast media after intraarterial, intravenous, or intrathecal administration. The behavior of water-soluble contrast media at these interfaces is discussed on the basis of local experience and a review of the literature

  18. Comparative toxicity of water soluble fractions of four oils on the growth of a Microalga

    Digital Repository Service at National Institute of Oceanography (India)

    Phatarpekar, P.V.; Ansari, Z.A.

    Toxic effects of water soluble fractions (WSF) of four different fuel oils on a microalga. Tetraselmis gracilis, were examined and compared. On applying different concentrations of WSF, a decrease in cell population was observed. Depending...

  19. Application of spray-drying and electrospraying/electospinning for poorly water-soluble drugs

    DEFF Research Database (Denmark)

    Bohr, Adam; Boetker, Johan P; Rades, Thomas

    2014-01-01

    Solid dispersions have been widely studied as an attractive formulation strategy for the increasingly prevalent poorly water-soluble drug compounds, including herbal medicines, often leading to improvements in drug dissolution rate and bioavailability. However, several challenges are encountered...

  20. Intestinal absorption of water-soluble vitamins in health and disease

    OpenAIRE

    Said, Hamid M.

    2011-01-01

    Our knowledge of the mechanisms and regulation of intestinal absorption of water-soluble vitamins under normal physiological conditions, and of the factors/conditions that affect and interfere with theses processes has been significantly expanded in recent years as a result of the availability of a host of valuable molecular/cellular tools. Although structurally and functionally unrelated, the water-soluble vitamins share the feature of being essential for normal cellular functions, growth an...

  1. Bioassay using the water soluble fraction of a Nigerian Light Crude ...

    African Journals Online (AJOL)

    Summary: A 96-hour bioassay was conducted using the water soluble fraction of a Nigerian light crude oil sample on Clarias gariepinus fingerlings. 0, 2.5, 5.0, 7.5 and 10 mls of water soluble fractions (WSF) of the oil were added to 1000 litres of de-chlorinated tap water to form 0, 25, 50 , 75 and 100 parts per million ...

  2. The role of vitamins in the diet of the elderly II. Water-soluble vitamins

    OpenAIRE

    Csapó J.; Albert Cs.; Prokisch J.

    2017-01-01

    Following a presentation of humans’ water-soluble vitamin requirements, the authors will discuss in detail the role these vitamins play in human organism and outline those major biochemical processes that are negatively affected in the body in case of vitamin deficiency. They point out that in the elderly population of developed countries cases of water-soluble vitamin deficiency are extremely rare and they are due to the lack of dietary vitamin, but mostly to the vitamin being released from ...

  3. Effect of fasting on the urinary excretion of water-soluble vitamins in humans and rats.

    Science.gov (United States)

    Fukuwatari, Tsutomu; Yoshida, Erina; Takahashi, Kei; Shibata, Katsumi

    2010-01-01

    Recent studies showed that the urinary excretion of the water-soluble vitamins can be useful as a nutritional index. To determine how fasting affects urinary excretion of water-soluble vitamins, a human study and an animal experiment were conducted. In the human study, the 24-h urinary excretion of water-soluble vitamins in 12 healthy Japanese adults fasting for a day was measured. One-day fasting drastically decreased urinary thiamin content to 30%, and increased urinary riboflavin content by 3-fold. Other water-soluble vitamin contents did not show significant change by fasting. To further investigate the alterations of water-soluble vitamin status by starvation, rats were starved for 3 d, and water-soluble vitamin contents in the liver, blood and urine were measured during starvation. Urinary excretion of thiamin, riboflavin, vitamin B(6) metabolite 4-pyridoxic acid, nicotinamide metabolites and folate decreased during starvation, but that of vitamin B(12), pantothenic acid and biotin did not. As for blood vitamin levels, only blood vitamin B(1), plasma PLP and plasma folate levels decreased with starvation. All water-soluble vitamin contents in the liver decreased during starvation, whereas vitamin concentrations in the liver did not decrease. Starvation decreased only concentrations of vitamin B(12) and folate in the skeletal muscle. These results suggest that water-soluble vitamins were released from the liver, and supplied to the peripheral tissues to maintain vitamin nutrition. Our human study also suggested that the effect of fasting should be taken into consideration for subjects showing low urinary thiamin and high urinary riboflavin.

  4. Evaluation of ammonium nitrate phosphate (Suphala) having different water soluble phosphorus levels on black soils

    International Nuclear Information System (INIS)

    Deo Dutt; Mutatkar, V.K.; Chapke, V.G.

    1974-01-01

    Efficiency of the laboratory prepared 32 P tagged ammonium nitrate phosphate (Suphala) varying in water soluble P was studied both on calcareous and non-calcareous soils of Maharashtra for bajra and wheat crops under greenhouse conditions. The results revealed a significant increase in dry matter production and uptake of total and fertilizer P with Suphala containing 30-32% water-soluble phosphorus. (author)

  5. Abalone water-soluble matrix for self-healing biomineralization of tooth defects

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Zhenliang [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Chen, Jingdi, E-mail: ibptcjd@fzu.edu.cn [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Wang, Hailiang [The Affiliated Stomatological Hospital, Fujian Medical University, Fuzhou 350002 (China); Zhong, Shengnan; Hu, Yimin; Wang, Zhili [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Zhang, Qiqing, E-mail: zhangqiq@126.com [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Institute of Biomedical Engineering, Chinese Academy of Medical Science & Peking Union Medical College, Tianjin 300192 (China)

    2016-10-01

    Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% the abalone water-soluble protein (AWSPro) and 2.04 wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application. - Graphical abstract: In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% abalone water-soluble protein (AWSPro) and 2.04 wt% abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro by self-organized. Display Omitted - Highlights: • Provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell. • The abalone shell water-soluble matrix contains protein and polysaccharide. • The abalone water-soluble matrix can efficiently induce remineralization of HAP by self-organized. • Achieved self-healing biomineralization of tooth defects in

  6. Water soluble organic aerosols in the Colorado Rocky Mountains, USA: composition, sources and optical properties

    OpenAIRE

    Xie, Mingjie; Mladenov, Natalie; Williams, Mark W.; Neff, Jason C.; Wasswa, Joseph; Hannigan, Michael P.

    2016-01-01

    Atmospheric aerosols have been shown to be an important input of organic carbon and nutrients to alpine watersheds and influence biogeochemical processes in these remote settings. For many remote, high elevation watersheds, direct evidence of the sources of water soluble organic aerosols and their chemical and optical characteristics is lacking. Here, we show that the concentration of water soluble organic carbon (WSOC) in the total suspended particulate (TSP) load at a high elevation site in...

  7. Abalone water-soluble matrix for self-healing biomineralization of tooth defects

    International Nuclear Information System (INIS)

    Wen, Zhenliang; Chen, Jingdi; Wang, Hailiang; Zhong, Shengnan; Hu, Yimin; Wang, Zhili; Zhang, Qiqing

    2016-01-01

    Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% the abalone water-soluble protein (AWSPro) and 2.04 wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application. - Graphical abstract: In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% abalone water-soluble protein (AWSPro) and 2.04 wt% abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro by self-organized. Display Omitted - Highlights: • Provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell. • The abalone shell water-soluble matrix contains protein and polysaccharide. • The abalone water-soluble matrix can efficiently induce remineralization of HAP by self-organized. • Achieved self-healing biomineralization of tooth defects in vitro.

  8. Oral water soluble contrast for malignant bowel obstruction.

    Science.gov (United States)

    Syrmis, William; Richard, Russell; Jenkins-Marsh, Sue; Chia, Siew C; Good, Phillip

    2018-03-07

    Malignant bowel obstruction (MBO) is a common problem in patients with intra-abdominal cancer. Oral water soluble contrast (OWSC) has been shown to be useful in the management of adhesive small bowel obstruction in identifying patients who will recover with conservative management alone and also in reducing the length of hospital stay. It is not clear whether the benefits of OWSC in adhesive small bowel obstruction are also seen in patients with MBO. To determine the reliability of OWSC media and follow-up abdominal radiographs in predicting the success of conservative treatment in resolving inoperable MBO with conservative management.To determine the efficacy and safety of OWSC media in reducing the duration of obstruction and reducing hospital stay in people with MBO. We identified studies from searching Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and MEDLINE in Process, Embase, CINAHL, Science Citation Index (Web of Science) and Conference Proceedings Citation Index - Science (Web of Science). We also searched registries of clinical trials and the CareSearch Grey Literature database. The date of the search was the 6 June 2017. Randomised controlled trials (RCTs), or prospective controlled studies, that evaluated the diagnostic potential of OWSC in predicting which malignant bowel obstructions will resolve with conservative treatment.RCTs, or prospective controlled studies, that assessed the therapeutic potential of OWSC in managing MBO at any level compared with placebo, no intervention or usual treatment or supportive care. We used standard methodological procedures expected by Cochrane. We assessed risk of bias and assessed the evidence using GRADE and created a 'Summary of findings' table. We found only one RCT meeting the selection criteria for the second objective (therapeutic potential) of this review. This study recruited nine participants. It compared the use of gastrografin versus placebo in adult patients with MBO with no

  9. Poly(ethylene oxide)–Poly(propylene oxide)-Based Copolymers for ...

    African Journals Online (AJOL)

    Amphiphilic poly(ethylene oxide)–poly(propylene oxide) (PEO–PPO)-based copolymers are thermoresponsive materials having aggregation properties in aqueous medium. As hydrosolubilizers of poorly water-soluble drugs and improved stability of sensitive agents, these materials have been investigated for improvement ...

  10. Fluorescence quenching behaviour of uric acid interacting with water-soluble cationic porphyrin

    International Nuclear Information System (INIS)

    Makarska-Bialokoz, Magdalena; Borowski, Piotr

    2015-01-01

    The process of association between 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H 2 TTMePP) and uric acid as well as its sodium salt has been studied in aqueous NaOH solution analysing its absorption and steady-state fluorescence spectra. The fluorescence quenching effect observed during interactions porphyrin-uric acid compounds points at the fractional accessibility of the fluorophore for the quencher. The association and fluorescence quenching constants are of the order of magnitude of 10 5 mol −1 . The fluorescence lifetimes and the quantum yields of the porphyrin anionic form were established. The results demonstrate that uric acid and its sodium salt can interact with H 2 TTMePP at basic pH and through formation of stacking complexes are able to quench its ability to emission. - Highlights: • Association study of water soluble cationic porphyrin with uric acid. • Porphyrin absorption spectra undergo the bathochromic and hypochromic effects. • Uric acid interacts with porphyrin in inhibiting manner, quenching its emission. • Fluorescence quenching effect testifies for the partial inactivation of a porphyrin. • The association and fluorescence quenching constants were calculated

  11. Fluorescence quenching behaviour of uric acid interacting with water-soluble cationic porphyrin

    Energy Technology Data Exchange (ETDEWEB)

    Makarska-Bialokoz, Magdalena, E-mail: makarska@hektor.umcs.lublin.pl [Department of Inorganic Chemistry, Maria Curie-Sklodowska University M. C. Sklodowska Sq. 2, 20-031 Lublin (Poland); Borowski, Piotr [Faculty of Chemistry, Maria Curie-Sklodowska University M. C. Sklodowska Sq. 3, 20-031 Lublin (Poland)

    2015-04-15

    The process of association between 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H{sub 2}TTMePP) and uric acid as well as its sodium salt has been studied in aqueous NaOH solution analysing its absorption and steady-state fluorescence spectra. The fluorescence quenching effect observed during interactions porphyrin-uric acid compounds points at the fractional accessibility of the fluorophore for the quencher. The association and fluorescence quenching constants are of the order of magnitude of 10{sup 5} mol{sup −1}. The fluorescence lifetimes and the quantum yields of the porphyrin anionic form were established. The results demonstrate that uric acid and its sodium salt can interact with H{sub 2}TTMePP at basic pH and through formation of stacking complexes are able to quench its ability to emission. - Highlights: • Association study of water soluble cationic porphyrin with uric acid. • Porphyrin absorption spectra undergo the bathochromic and hypochromic effects. • Uric acid interacts with porphyrin in inhibiting manner, quenching its emission. • Fluorescence quenching effect testifies for the partial inactivation of a porphyrin. • The association and fluorescence quenching constants were calculated.

  12. Development of lipid-shell and polymer core nanoparticles with water-soluble salidroside for anti-cancer therapy.

    Science.gov (United States)

    Fang, Dai-Long; Chen, Yan; Xu, Bei; Ren, Ke; He, Zhi-Yao; He, Li-Li; Lei, Yi; Fan, Chun-Mei; Song, Xiang-Rong

    2014-02-25

    Salidroside (Sal) is a potent antitumor drug with high water-solubility. The clinic application of Sal in cancer therapy has been significantly restricted by poor oral absorption and low tumor cell uptake. To solve this problem, lipid-shell and polymer-core nanoparticles (Sal-LPNPs) loaded with Sal were developed by a double emulsification method. The processing parameters including the polymer types, organic phase, PVA types and amount were systemically investigated. The obtained optimal Sal-LPNPs, composed of PLGA-PEG-PLGA triblock copolymers and lipids, had high entrapment efficiency (65%), submicron size (150 nm) and negatively charged surface (-23 mV). DSC analysis demonstrated the successful encapsulation of Sal into LPNPs. The core-shell structure of Sal-LPNPs was verified by TEM. Sal released slowly from the LPNPs without apparent burst release. MTT assay revealed that 4T1 and PANC-1 cancer cell lines were sensitive to Sal treatment. Sal-LPNPs had significantly higher antitumor activities than free Sal in 4T1 and PANC-1 cells. The data indicate that LPNPs are a promising Sal vehicle for anti-cancer therapy and worthy of further investigation.

  13. Development of Lipid-Shell and Polymer Core Nanoparticles with Water-Soluble Salidroside for Anti-Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Dai-Long Fang

    2014-02-01

    Full Text Available Salidroside (Sal is a potent antitumor drug with high water-solubility. The clinic application of Sal in cancer therapy has been significantly restricted by poor oral absorption and low tumor cell uptake. To solve this problem, lipid-shell and polymer-core nanoparticles (Sal-LPNPs loaded with Sal were developed by a double emulsification method. The processing parameters including the polymer types, organic phase, PVA types and amount were systemically investigated. The obtained optimal Sal-LPNPs, composed of PLGA-PEG-PLGA triblock copolymers and lipids, had high entrapment efficiency (65%, submicron size (150 nm and negatively charged surface (−23 mV. DSC analysis demonstrated the successful encapsulation of Sal into LPNPs. The core-shell structure of Sal-LPNPs was verified by TEM. Sal released slowly from the LPNPs without apparent burst release. MTT assay revealed that 4T1 and PANC-1 cancer cell lines were sensitive to Sal treatment. Sal-LPNPs had significantly higher antitumor activities than free Sal in 4T1 and PANC-1 cells. The data indicate that LPNPs are a promising Sal vehicle for anti-cancer therapy and worthy of further investigation.

  14. Associative, thermodynamic and thermo-kinetics behavior of di- and triblock copolymers of oxyethylene and oxybutylene in aqueous media

    International Nuclear Information System (INIS)

    Khan, Abbas; Siddiq, Mohammad

    2014-01-01

    Highlights: • Associative, thermodynamic and thermo-kinetics behavior was investigated. • Micellization of these copolymer is spontaneous, endothermic and entropy driven. • Micelles are spherical in shape and their nature depends on temperature. • Fusion/fission mechanism dominates over unimer entry/expulsion for micellar dynamics. • Micellar parameters depend on temperature and on the delicate hydrophobic–hydrophilic balance of the blocks. - Abstract: The associative, thermodynamic and thermo-kinetics properties of a diblock E 90 B 10 and three triblock copolymers based on polyoxyethylene and polyoxybutylene of the type E m B 10 E m water have been studied by surface tensiometry, light scattering and temperature-jump stopped-flow techniques. The data from surface tension was helpful to detect the critical micelle concentration (CMC) as well as to calculate the thermodynamic parameters of micellization. Dynamic light scattering (DLS) was employed to obtain the values of hydrodynamic radii (R h ), volume (υ h ) and hydrodynamic expansion parameter (δ h ) of the micelle at different temperatures. Similarly, static light scattering (SLS) measurements made us enable to find out various micellar parameters such as; weight-average molar (M w ), association number (N w ), thermodynamic radius (R t ), thermodynamic volume (υ t ), anhydrous volume (υ a ) and thermodynamic expansion parameter (δ t ) of the micelles. Likewise, the kinetics of micellar aggregation/dynamic was also investigated by using temperature-jump stopped-flow technique in the temperature range of 20–50 °C

  15. Atmospheric water-soluble organic nitrogen (WSON) in the eastern Mediterranean: origin and ramifications regarding marine productivity

    Science.gov (United States)

    Nehir, Münevver; Koçak, Mustafa

    2018-03-01

    Aerosol and rain sampling in two size fractions was carried out at a rural site located on the coast of the eastern Mediterranean, Erdemli, Turkey (36°33'54'' N, 34°15'18'' E). A total of 674 aerosol samples in two size fractions (337 coarse, 337 fine) and 23 rain samples were collected between March 2014 and April 2015. Samples were analyzed for NO3-, NH4+ and ancillary water-soluble ions using ion chromatography and water-soluble total nitrogen (WSTN) by applying a high-temperature combustion method. The mean aerosol water-soluble organic nitrogen (WSON) was 23.8 ± 16.3 nmol N m-3, reaching a maximum of 79 nmol N m-3, with about 66 % being associated with coarse particles. The volume weighted mean (VWM) concentration of WSON in rain was 21.5 µmol N L-1. The WSON contributed 37 and 29 % to the WSTN in aerosol and rainwater, respectively. Aerosol WSON concentrations exhibited large temporal variation, mainly due to meteorology and the origin of air mass flow. The highest mean aerosol WSON concentration was observed in the summer and was attributed to the absence of rain and resuspension of cultivated soil in the region. The mean concentration of WSON during dust events (38.2 ± 17.5 nmol N m-3) was 1.3 times higher than that of non-dust events (29.4 ± 13.9 nmol N m-3). Source apportionment analysis demonstrated that WSON was originated from agricultural activities (43 %), secondary aerosol (20 %), nitrate (22 %), crustal material (10 %) and sea salt (5 %). The dry and wet depositions of WSON were equivalent and amounted to 36 % of the total atmospheric WSTN flux.

  16. Evaluation of solution and rheological properties for hydrophobically associated polyacrylamide copolymer as a promised enhanced oil recovery candidate

    Directory of Open Access Journals (Sweden)

    A.N. El-hoshoudy

    2017-09-01

    Full Text Available Crude oil is the most critical energy source in the world, especially for transportation, provision of heat and light as there has not been a sufficient energy source to replace crude oil has broadly integrated, so there is an urgent need to maximize the extraction of the original oil in-place for every reservoir, and accelerating the development of enhanced oil recovery (EOR technologies. Polymer flooding by hydrophobically associated polyacrylamides (HAPAM is a widely used technique through EOR technology. For successful application of these polymers, one should evaluate rheological and solution properties at simulated reservoir conditions as a function of polymer concentration, salinity, temperature and shear rate. The results showed that these copolymers exhibit favorable salt tolerance, temperature resistance, and recoverable viscosity after shearing, reasonable thickening behavior and improved viscosity enhancement properties due to presence of hydrophobic association in the copolymer main chains. Moreover, its capacity for oil production improvement was evaluated during flooding experiments through one dimensional sandstone model at simulated reservoir conditions.

  17. Preparation and Characterization of Water-Soluble Chitosan Microparticles Loaded with Insulin Using the Polyelectrolyte Complexation Method

    International Nuclear Information System (INIS)

    Wu, S.; Tao, Y.; Zhang, H.; Su, Z.

    2011-01-01

    Polymeric delivery systems based on microparticles have emerged as a promising approach for peroral insulin delivery. The amount of insulin was quantified by the improved Bradford method. It was shown that water-soluble chitosan/insulin/tripolyphosphate (TPP) mass ratio played an important role in microparticles formation. Stable, uniform, and spherical water-soluble chitosan microparticles (WSC-MPs) with high insulin association efficiency were formed at or close to optimized WSC/insulin/TPP mass ratio. WSC-MPs had higher association efficiency in the ph 4.0 and ph 9.7 of TPP solution. The results showed that association efficiency and loading capacity of insulin-loaded WSC-MPs prepared in 0.01 mol/L HCl of insulin were 48.28 ± 0.90% and 9.52 ± 1.34%. The average size of insulin-loaded WSC-MPs was 292 nm. The presented WSC microparticulate system has promising properties towards the development of an oral delivery system for insulin

  18. [Characteristics of mass size distributions of water-soluble, inorganic ions during summer and winter haze days of Beijing].

    Science.gov (United States)

    Huang, Yi-Min; Liu, Zi-Rui; Chen, Hong; Wang, Yue-Si

    2013-04-01

    To investigate the size distribution characteristics of water soluble inorganic ions in haze days, the particle samples were collected by two Andersen cascade impactors in Beijing during summer and winter time and each sampling period lasted two weeks. Online measurement of PM10 and PM2.5 using TEOM were also conducted at the same time. Sources and formation mechanism of water soluble inorganic ions were analyzed based on their size distributions. The results showed that average concentrations of PM10 and PM 2.5 were (245.5 +/- 8.4) microg x m(-3) and (120.2 +/- 2.0) microg x m(-3) during summer haze days (SHD), and were (384.2 +/- 30.2) microg x m(-3) and (252.7 +/- 47.1) microg x m(-3) during winter haze days (WHD), which suggested fine particles predominated haze pollution episode in both seasons. Total water-soluble inorganic ions concentrations were higher in haze days than those in non-haze days, especially in fine particles. Furthermore, concentrations of secondary inorganic ions (SO4(2-), NO3(-) and NH4(+)) increased quicker than other inorganic ions in fine particles during haze days, indicating secondary inorganic ions played an important role in the formation of haze pollution. Similar size distributions were found for all Sinorganic water soluble ions except for NO3(-), during SHD and WHD. SO4(2-) and NH4(+) dominated in the fine mode (PM1.0) while Mg2+ and Ca2+ accumulated in coarse fraction, Na+, Cl- and K+ showed a bimodal distribution. For NO3(-), however, it showed a bimodal distribution during SHD and a unimodal distribution dominated in the fine fraction was found during WHD. The average mass median aerodynamic diameter (MMAD) of SO4(2-) was 0.64 microm in SHD, which suggested the formation of SO4(2-) was mainly attributed to in-cloud processes. Furthermore, a higher apparent conversion rate of sulfur dioxide (SOR) was found in SHD, indicating more fine particles were produced by photochemical reaction in haze days than that in non-haze days. The

  19. Temperature-dependent photoluminescence of water-soluble quantum dots for a bioprobe

    International Nuclear Information System (INIS)

    Liu Tiancai; Huang Zhenli; Wang Haiqiao; Wang Jianhao; Li Xiuqing; Zhao Yuandi; Luo Qingming

    2006-01-01

    The photoluminescence of water-soluble CdSe/ZnS core/shell quantum dots is found to be temperature-dependent: as temperature arising from 280 K to 351 K, the photoluminescence declines with emission peak shifting towards the red at a rate of ∼0.11 nm K -1 . And the studies show that the photoluminescence of water-soluble CdSe/ZnS quantum dots with core capped by a thinner ZnS shell is more sensitive to temperature than that of ones with core capped by a thicker one. That is, with 50% decrement of the quantum yield the temperature of the former need to arise from 280 K to 295 K, while the latter requires much higher temperature (315.6 K), which means that the integrality of shell coverage is a very important factor on temperature-sensitivity to for the photoluminescence of water-soluble CdSe/ZnS quantum dots. Moreover, it is found that the water-soluble CdSe quantum dots with different core sizes, whose cores are capped by thicker ZnS shells, possess almost the same sensitivity to the temperature. All of the studies about photoluminescence temperature-dependence of water-soluble CdSe/ZnS core/shell quantum dots show an indispensable proof for their applications in life science

  20. Study on Mixed Solvency Concept in Formulation Development of Aqueous Injection of Poorly Water Soluble Drug

    Directory of Open Access Journals (Sweden)

    Shailendra Singh Solanki

    2013-01-01

    Full Text Available In the present investigation, mixed-solvency approach has been applied for the enhancement of aqueous solubility of a poorly water- soluble drug, zaltoprofen (selected as a model drug, by making blends (keeping total concentrations 40% w/v, constant of selected water-soluble substances from among the hydrotropes (urea, sodium benzoate, sodium citrate, nicotinamide; water-soluble solids (PEG-4000, PEG-6000; and co-solvents (propylene glycol, glycerine, PEG-200, PEG-400, PEG-600. Aqueous solubility of drug in case of selected blends (12 blends ranged from 9.091 ± 0.011 mg/ml–43.055 ± 0.14 mg/ml (as compared to the solubility in distilled water 0.072 ± 0.012 mg/ml. The enhancement in the solubility of drug in a mixed solvent containing 10% sodium citrate, 5% sodium benzoate and 25 % S cosolvent (25% S cosolvent contains PEG200, PEG 400, PEG600, Glycerine and Propylene glycol was more than 600 fold. This proved a synergistic enhancement in solubility of a poorly water-soluble drug due to mixed cosolvent effect. Each solubilized product was characterized by ultraviolet and infrared techniques. Various properties of solution such as pH, viscosity, specific gravity and surface tension were studied. The developed formulation was studied for physical and chemical stability. This mixed solvency shall prove definitely a boon for pharmaceutical industries for the development of dosage form of poorly water soluble drugs.

  1. Water soluble {2-[3-(diethylamino)phenoxy]ethoxy} substituted zinc(II) phthalocyanine photosensitizers

    Energy Technology Data Exchange (ETDEWEB)

    Çakır, Dilek [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Göl, Cem [Gebze Institute of Technology, Department of Chemistry, PO Box 141, Gebze, 41400, Kocaeli (Turkey); Çakır, Volkan [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Durmuş, Mahmut [Gebze Institute of Technology, Department of Chemistry, PO Box 141, Gebze, 41400, Kocaeli (Turkey); Bıyıklıoğlu, Zekeriya, E-mail: zekeriya_61@yahoo.com [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Kantekin, Halit [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2015-03-15

    The new peripherally and non-peripherally tetra-{2-[3-(diethylamino)phenoxy] ethoxy} substituted zinc phthalocyanines (2a and 3a) were synthesized by cyclotetramerization of phthalonitrile derivatives (2 and 3). 2-[3-(diethylamino)phenoxy] ethoxy group was chosen as substituent because the quaternization of the diethylamino functionality on the structure of this group produced water soluble zinc phthalocyanines (2b and 3b). The water solubility is very important for many different applications such as photosensitizers in the photodynamic therapy of cancer because the water soluble photosensitizers can be injected directly to the body and they can transport to cancer cells through blood stream. The new compounds were characterized by using elemental analysis, UV–vis, IR, {sup 1}H NMR, {sup 13}C NMR and mass spectroscopies. The photophysical and photochemical properties of these novel photosensitizer compounds were examined in DMSO (both non-ionic and ionic complexes) and in PBS (for ionic complexes) solutions. The investigation of these properties is very important for the usage of the compounds as photosensitizers for PDT because determination of these properties is the first stage of potential of the compounds as photosensitizers. The bovine serum albumin (BSA) and DNA binding behaviour of the studied water soluble zinc (II) phthalocyanines were also investigated in PBS solutions for the determination of biological activity of these compounds. - Highlights: • Synthesis of water soluble zinc phthalocyanines. • Photophysical and photochemical properties for phthalocyanines. • Photodynamic therapy studies.

  2. The role of vitamins in the diet of the elderly II. Water-soluble vitamins

    Directory of Open Access Journals (Sweden)

    Csapó J.

    2017-10-01

    Full Text Available Following a presentation of humans’ water-soluble vitamin requirements, the authors will discuss in detail the role these vitamins play in human organism and outline those major biochemical processes that are negatively affected in the body in case of vitamin deficiency. They point out that in the elderly population of developed countries cases of water-soluble vitamin deficiency are extremely rare and they are due to the lack of dietary vitamin, but mostly to the vitamin being released from its bindings, the difficulty of free vitamin absorption, gastrointestinal problems, medication, and often alcoholism. Among water-soluble vitamins, B12 is the only one with a sufficient storage level in the body, capable of preventing deficiency symptoms for a long period of time in cases of vitamin-deficient nutrition. Each type of vitamin is dealt with separately in discussing the beneficial outcomes of their overconsumption regarding health, while the authors of the article also present cases with contradictory results. Daily requirements are set forth for every water-soluble vitamin and information is provided on the types of nutrients that help us to the water-soluble vitamins essential for the organism.

  3. Water Soluble Vitamins Enhance the Growth of Microorganisms in Peripheral Parenteral Nutrition Solutions.

    Science.gov (United States)

    Omotani, Sachiko; Tani, Katsuji; Nagai, Katsuhito; Hatsuda, Yasutoshi; Mukai, Junji; Myotoku, Michiaki

    2017-01-01

    Peripheral parenteral nutrition (PPN) solutions contain amino acids, glucose, and electrolytes, with or without some water soluble vitamins. Peripheral venous catheters are one of the causes of catheter related blood stream infection (CRBSI), which requires infection control. In Japan, PPN solutions have rarely been prepared under aseptic conditions. However, in recent years, the necessity of adding vitamins to infusions has been reported. Therefore, we investigated the effects of water soluble vitamins on growth of microorganisms in PPN solutions. AMINOFLUID ® (AF), BFLUID ® (BF), PARESAFE ® (PS) and PAREPLUS ® (PP) PPN solutions were used. Water soluble vitamins contained in PP were also used. Causative microorganisms of CRBSI were used. Staphylococcus epidermidis decreased after 24 hours or 48 hours in all solutions. On the other hand, Escherichia coli , Serratia marcescens , Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans increased, especially in PP. When each water soluble vitamin was added to BF and PS, growth of S. aureus was greater in solutions that contained nicotinamide than in solutions that contained other vitamins. As for C. albicans , they grew in all test solutions. C. albicans grew especially well in solutions that contained biotin. When commercial amino acids and glucose solutions with electrolytes are administered, in particular those containing multivitamins or water soluble vitamins, efforts to control infection must be taken to prevent proliferation of microorganisms.

  4. Temperature-dependent photoluminescence of water-soluble quantum dots for a bioprobe

    Energy Technology Data Exchange (ETDEWEB)

    Liu Tiancai [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Huang Zhenli [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wang Haiqiao [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wang Jianhao [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Li Xiuqing [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Zhao Yuandi [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)]. E-mail: zydi@mail.hust.edu.cn; Luo Qingming [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

    2006-02-10

    The photoluminescence of water-soluble CdSe/ZnS core/shell quantum dots is found to be temperature-dependent: as temperature arising from 280 K to 351 K, the photoluminescence declines with emission peak shifting towards the red at a rate of {approx}0.11 nm K{sup -1}. And the studies show that the photoluminescence of water-soluble CdSe/ZnS quantum dots with core capped by a thinner ZnS shell is more sensitive to temperature than that of ones with core capped by a thicker one. That is, with 50% decrement of the quantum yield the temperature of the former need to arise from 280 K to 295 K, while the latter requires much higher temperature (315.6 K), which means that the integrality of shell coverage is a very important factor on temperature-sensitivity to for the photoluminescence of water-soluble CdSe/ZnS quantum dots. Moreover, it is found that the water-soluble CdSe quantum dots with different core sizes, whose cores are capped by thicker ZnS shells, possess almost the same sensitivity to the temperature. All of the studies about photoluminescence temperature-dependence of water-soluble CdSe/ZnS core/shell quantum dots show an indispensable proof for their applications in life science.

  5. Membrane Proteins Are Dramatically Less Conserved than Water-Soluble Proteins across the Tree of Life.

    Science.gov (United States)

    Sojo, Victor; Dessimoz, Christophe; Pomiankowski, Andrew; Lane, Nick

    2016-11-01

    Membrane proteins are crucial in transport, signaling, bioenergetics, catalysis, and as drug targets. Here, we show that membrane proteins have dramatically fewer detectable orthologs than water-soluble proteins, less than half in most species analyzed. This sparse distribution could reflect rapid divergence or gene loss. We find that both mechanisms operate. First, membrane proteins evolve faster than water-soluble proteins, particularly in their exterior-facing portions. Second, we demonstrate that predicted ancestral membrane proteins are preferentially lost compared with water-soluble proteins in closely related species of archaea and bacteria. These patterns are consistent across the whole tree of life, and in each of the three domains of archaea, bacteria, and eukaryotes. Our findings point to a fundamental evolutionary principle: membrane proteins evolve faster due to stronger adaptive selection in changing environments, whereas cytosolic proteins are under more stringent purifying selection in the homeostatic interior of the cell. This effect should be strongest in prokaryotes, weaker in unicellular eukaryotes (with intracellular membranes), and weakest in multicellular eukaryotes (with extracellular homeostasis). We demonstrate that this is indeed the case. Similarly, we show that extracellular water-soluble proteins exhibit an even stronger pattern of low homology than membrane proteins. These striking differences in conservation of membrane proteins versus water-soluble proteins have important implications for evolution and medicine. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  6. Amelioration of radiation induced oxidative stress using water soluble chitosan produced by Aspergillus niger

    International Nuclear Information System (INIS)

    EL-Sonbaty, S.M.; Swailam, H.M.; Noaman, E.

    2012-01-01

    Chitosan is a natural polysaccharide synthesized by a great number of living organisms and considered as a source of potential bioactive material and has many biological applications which are greatly affected by its solubility in neutral ph. In this study low molecular weight water soluble chitosan was prepared by chemical degradation of chitosan produced by Aspergillus niger using H 2 O 2 . Chitosan chemical structure was detected before and after treatment using FTIR spectrum, and its molecular weight was determined by its viscosity using viscometer. Its antioxidant activity against gamma radiation was evaluated in vivo using rats. Rats were divided into 4 groups; group 1: control, group 2: exposed to acute dose of gamma radiation (6 Gy), group 3: received water soluble chitosan, group 4: received water soluble chitosan then exposed to gamma radiation as group 2. Gamma radiation significantly increased malonaldehyde, decreased glutathione concentration, activity of superoxide dismutase, catalase, and glutatione peroxidase, while significantly increase the activity of alanine transferase, aspartate transferase, urea and creatinine concentration. Administration of water soluble chitosan has ameliorated induced changes caused by gamma radiation. It could be concluded that water soluble chitosan by scavenging free radicals directly or indirectly may act as a potent radioprotector against ionizing irradiation.

  7. Water soluble {2-[3-(diethylamino)phenoxy]ethoxy} substituted zinc(II) phthalocyanine photosensitizers

    International Nuclear Information System (INIS)

    Çakır, Dilek; Göl, Cem; Çakır, Volkan; Durmuş, Mahmut; Bıyıklıoğlu, Zekeriya; Kantekin, Halit

    2015-01-01

    The new peripherally and non-peripherally tetra-{2-[3-(diethylamino)phenoxy] ethoxy} substituted zinc phthalocyanines (2a and 3a) were synthesized by cyclotetramerization of phthalonitrile derivatives (2 and 3). 2-[3-(diethylamino)phenoxy] ethoxy group was chosen as substituent because the quaternization of the diethylamino functionality on the structure of this group produced water soluble zinc phthalocyanines (2b and 3b). The water solubility is very important for many different applications such as photosensitizers in the photodynamic therapy of cancer because the water soluble photosensitizers can be injected directly to the body and they can transport to cancer cells through blood stream. The new compounds were characterized by using elemental analysis, UV–vis, IR, 1 H NMR, 13 C NMR and mass spectroscopies. The photophysical and photochemical properties of these novel photosensitizer compounds were examined in DMSO (both non-ionic and ionic complexes) and in PBS (for ionic complexes) solutions. The investigation of these properties is very important for the usage of the compounds as photosensitizers for PDT because determination of these properties is the first stage of potential of the compounds as photosensitizers. The bovine serum albumin (BSA) and DNA binding behaviour of the studied water soluble zinc (II) phthalocyanines were also investigated in PBS solutions for the determination of biological activity of these compounds. - Highlights: • Synthesis of water soluble zinc phthalocyanines. • Photophysical and photochemical properties for phthalocyanines. • Photodynamic therapy studies

  8. Ubiquitous water-soluble molecules in aquatic plant exudates determine specific insect attraction.

    Science.gov (United States)

    Sérandour, Julien; Reynaud, Stéphane; Willison, John; Patouraux, Joëlle; Gaude, Thierry; Ravanel, Patrick; Lempérière, Guy; Raveton, Muriel

    2008-10-08

    Plants produce semio-chemicals that directly influence insect attraction and/or repulsion. Generally, this attraction is closely associated with herbivory and has been studied mainly under atmospheric conditions. On the other hand, the relationship between aquatic plants and insects has been little studied. To determine whether the roots of aquatic macrophytes release attractive chemical mixtures into the water, we studied the behaviour of mosquito larvae using olfactory experiments with root exudates. After testing the attraction on Culex and Aedes mosquito larvae, we chose to work with Coquillettidia species, which have a complex behaviour in nature and need to be attached to plant roots in order to obtain oxygen. This relationship is non-destructive and can be described as commensal behaviour. Commonly found compounds seemed to be involved in insect attraction since root exudates from different plants were all attractive. Moreover, chemical analysis allowed us to identify a certain number of commonly found, highly water-soluble, low-molecular-weight compounds, several of which (glycerol, uracil, thymine, uridine, thymidine) were able to induce attraction when tested individually but at concentrations substantially higher than those found in nature. However, our principal findings demonstrated that these compounds appeared to act synergistically, since a mixture of these five compounds attracted larvae at natural concentrations (0.7 nM glycerol, insect relationships in aquatic eco-systems.

  9. Case study of water-soluble metal containing organic constituents of biomass burning aerosol.

    Science.gov (United States)

    Chang-Graham, Alexandra L; Profeta, Luisa T M; Johnson, Timothy J; Yokelson, Robert J; Laskin, Alexander; Laskin, Julia

    2011-02-15

    Natural and prescribed biomass fires are a major source of aerosols that may persist in the atmosphere for several weeks. Biomass burning aerosols (BBA) can be associated with long-range transport of water-soluble N-, S-, P-, and metal-containing species. In this study, BBA samples were collected using a particle-into-liquid sampler (PILS) from laboratory burns of vegetation collected on military bases in the southeastern and southwestern United States. The samples were then analyzed using high resolution electrospray ionization mass spectrometry (ESI/HR-MS) that enabled accurate mass measurements for hundreds of species with m/z values between 70 and 1000 and assignment of elemental formulas. Mg, Al, Ca, Cr, Mn, Fe, Ni, Cu, Zn, and Ba-containing organometallic species were identified. The results suggest that the biomass may have accumulated metal-containing species that were re-emitted during biomass burning. Further research into the sources, dispersion, and persistence of metal-containing aerosols, as well as their environmental effects, is needed.

  10. Visualizing monolayers with a water-soluble fluorophore to quantify adsorption, desorption, and the double layer.

    Science.gov (United States)

    Shieh, Ian C; Zasadzinski, Joseph A

    2015-02-24

    Contrast in confocal microscopy of phase-separated monolayers at the air-water interface can be generated by the selective adsorption of water-soluble fluorescent dyes to disordered monolayer phases. Optical sectioning minimizes the fluorescence signal from the subphase, whereas convolution of the measured point spread function with a simple box model of the interface provides quantitative assessment of the excess dye concentration associated with the monolayer. Coexisting liquid-expanded, liquid-condensed, and gas phases could be visualized due to differential dye adsorption in the liquid-expanded and gas phases. Dye preferentially adsorbed to the liquid-disordered phase during immiscible liquid-liquid phase coexistence, and the contrast persisted through the critical point as shown by characteristic circle-to-stripe shape transitions. The measured dye concentration in the disordered phase depended on the phase composition and surface pressure, and the dye was expelled from the film at the end of coexistence. The excess concentration of a cationic dye within the double layer adjacent to an anionic phospholipid monolayer was quantified as a function of subphase ionic strength, and the changes in measured excess agreed with those predicted by the mean-field Gouy-Chapman equations. This provided a rapid and noninvasive optical method of measuring the fractional dissociation of lipid headgroups and the monolayer surface potential.

  11. Phytotoxicity of water-soluble substances from alfalfa and barley soil extracts on four crop species.

    Science.gov (United States)

    Read, J J; Jensen, E H

    1989-02-01

    Problems associated with continuously planting alfalfa (Medicago saliva L.) or seeding to thicken depleted alfalfa stands may be due to autotoxicity, an intraspecific form of allelopathy. A bioassay approach was utilized to characterize the specificity and chemical nature of phytotoxins in extracts of alfalfa soils as compared to fallow soil or soil where a cereal was the previous crop. In germination chamber experiments, water-soluble substances present in methanol extracts of soil cropped to alfalfa or barley (Hordeum vulgare L.) decreased seedling root length of alfalfa L-720, winter wheat (Triticum aestivum L. Nugaines) and radish (Raphanus sativa L. Crimson Giant). Five days after germination, seedling dry weights of alfalfa and radish in alfalfa soil extracts were lower compared to wheat or red clover (Trifolium pralense L. Kenland). Growth of red clover was not significantly reduced by soil extracts from cropped soil. Extracts of crop residue screened from soil cropped to alfalfa or barley significantly reduced seedling root length; extracts of alfalfa residue caused a greater inhibition of seedling dry weight than extracts of barely residue. A phytotoxic, unidentified substance present in extracts of crop residue screened from alfalfa soil, which inhibited seedling root length of alfalfa, was isolated by thin-layer chromatography (TLC). Residues from a soil cropped continuously to alfalfa for 10 years had the greatest phytotoxic activity.

  12. Water-Soluble Dinitrosyl Iron Complex (DNIC): a Nitric Oxide Vehicle Triggering Cancer Cell Death via Apoptosis.

    Science.gov (United States)

    Wu, Shou-Cheng; Lu, Chung-Yen; Chen, Yi-Lin; Lo, Feng-Chun; Wang, Ting-Yin; Chen, Yu-Jen; Yuan, Shyng-Shiou; Liaw, Wen-Feng; Wang, Yun-Ming

    2016-09-19

    Nitric oxide (NO) is an important cellular signaling molecule that modulates various physiological activities. Angiogenesis-promoting activities of NO-donor drugs have been explored in both experimental and clinical studies. In this study, a structurally well characterized and water-soluble neutral {Fe(NO)2}(9) DNIC [(S(CH2)2OH)(S(CH2)2NH3)Fe(NO)2] (DNIC 2) was synthesized to serve as a NO-donor species. The antitumor activity of DNIC 2 was determined by MTT assay, confocal imaging, and Annexin-V/PI staining. The IC50 values of DNIC 2 were 18.8, 42.9, and 38.6 μM for PC-3, SKBR-3, and CRL5866 tumor cells, respectively. Moreover, DNIC 2 promoted apoptotic cell death via activation of apoptosis-associated proteins and inhibition of survival associated proteins. In particular, DNIC 2 treatment suppressed PC-3 tumor growth by 2.34- and 19.3-fold at 7 and 21 days, in comparison with the control group. These results indicate that water-soluble DNIC 2 may serve as a promising drug for cancer therapy.

  13. Separation of three water-soluble vitamins by poly(dimethylsiloxane) microchannel electrophoresis with electrochemical detection.

    Science.gov (United States)

    Li, Xiang-Yun; Zhang, Qian-Li; Lian, Hong-Zhen; Xu, Jing-Juan; Chen, Hong-Yuan

    2007-09-01

    A method for rapid separation and sensitive determination of three water-soluble vitamins, pyridoxine, ascorbic acid (VC), and p-aminobenzoic acid (PABA) has been developed by PDMS microchannel electrophoresis integrated with amperometric detection. After treatment of the microchip with oxygen plasma, the peak shapes of the three analytes were essentially improved. Pyridoxine, VC, and PABA were well separated within only 80 s in a running buffer of 20 mM borate solution (pH 8.5). Good linearity was obtained within the concentration range of 2-200 microM for the three water-soluble vitamins. The detection limits were 1.0 microM for pyridoxine and VC, and 1.5 microM for PABA. The proposed method has been successfully applied to real human urine sample, without solid phase extraction, with recoveries of 80-122% for the three water-soluble vitamins.

  14. Effect of supplementation of water-soluble vitamins on oxidative stress and blood pressure in prehypertensives.

    Science.gov (United States)

    Talikoti, Prashanth; Bobby, Zachariah; Hamide, Abdoul

    2015-01-01

    The objective of the study was to evaluate the effect of water-soluble vitamins on oxidative stress and blood pressure in prehypertensives. Sixty prehypertensives were recruited and randomized into 2 groups of 30 each. One group received water-soluble vitamins and the other placebo for 4 months. Further increase in blood pressure was not observed in the vitamin group which increased significantly in the placebo group at the end of 4 months. Malonedialdehyde and protein carbonylation were reduced during the course of treatment with vitamins whereas in the placebo group there was an increase in the level of malondialdehyde. In conclusion, supplementation of water-soluble vitamins in prehypertension reduces oxidative stress and its progression to hypertension.

  15. Urinary excretion levels of water-soluble vitamins in pregnant and lactating women in Japan.

    Science.gov (United States)

    Shibata, Katsumi; Fukuwatari, Tsutomu; Sasaki, Satoshi; Sano, Mitsue; Suzuki, Kahoru; Hiratsuka, Chiaki; Aoki, Asami; Nagai, Chiharu

    2013-01-01

    Recent studies have shown that the urinary excretion levels of water-soluble vitamins can be used as biomarkers for the nutritional status of these vitamins. To determine changes in the urinary excretion levels of water-soluble vitamins during pregnant and lactating stages, we surveyed and compared levels of nine water-soluble vitamins in control (non-pregnant and non-lactating women), pregnant and lactating women. Control women (n=37), women in the 2nd (16-27 wk, n=24) and 3rd trimester of pregnancy (over 28 wk, n=32), and early- (0-5 mo, n=54) and late-stage lactating (6-11 mo, n=49) women took part in the survey. The mean age of subjects was ~30 y, and mean height was ~160 cm. A single 24-h urine sample was collected 1 d after the completion of a validated, self-administered comprehensive diet history questionnaire to measure water-soluble vitamins or metabolites. The average intake of each water-soluble vitamin was ≍ the estimated average requirement value and adequate intake for the Japanese Dietary Reference Intakes in all life stages, except for vitamin B6 and folate intakes during pregnancy. No change was observed in the urinary excretion levels of vitamin B2, vitamin B6, vitamin B12, biotin or vitamin C among stages. Urine nicotinamide and folate levels were higher in pregnant women than in control women. Urine excretion level of vitamin B1 decreased during lactation and that of pantothenic acid decreased during pregnancy and lactation. These results provide valuable information for setting the Dietary Reference Intakes of water-soluble vitamins for pregnant and lactating women.

  16. Polymer-assisted synthesis of water-soluble PbSe quantum dots

    International Nuclear Information System (INIS)

    Melnig, V.; Apostu, M.-O.; Foca, N.

    2008-01-01

    Stable PbSe quantum dots were synthesised in water-based media using poly(amidehydroxyurethane) water-soluble polymer. The polymer acts like a precursor carrier, blocks the particles aggregation and assures their solubility. Atomic force microscopy data show that the particle radius is smaller than the Bohr radius of PbSe. Interactions studies, performed by Fourier transform IR spectroscopy, show that the quantum dots are capped with poly(amidehydroxyurethane). The proposed synthesis was realised in the absence of any organic solvent. As a result, the produced particles have good water solubility, stability and good arguments to be biologically compatible.

  17. Smart polyelectrolyte microcapsules as carriers for water-soluble small molecular drug.

    Science.gov (United States)

    Song, Weixing; He, Qiang; Möhwald, Helmuth; Yang, Yang; Li, Junbai

    2009-10-15

    Heat treatment is introduced as a simple method for the encapsulation of low molecular weight water-soluble drugs within layer-by-layer assembled microcapsules. A water-soluble drug, procainamide hydrochloride, could thus be encapsulated in large amount and enriched by more than 2 orders of magnitude in the assembled PDADMAC/PSS capsules. The shrunk capsules could control the unloading rate of drugs, and the drugs could be easily unloaded using ultrasonic treatment. The encapsulated amount could be quantitatively controlled via the drug concentration in the bulk. We also found that smaller capsules possess higher encapsulation capability.

  18. Lipid-based formulations for oral administration of poorly water-soluble drugs

    DEFF Research Database (Denmark)

    Mu, Huiling; Holm, René; Müllertz, Anette

    2013-01-01

    Lipid-based drug delivery systems have shown great potentials in oral delivery of poorly water-soluble drugs, primarily for lipophilic drugs, with several successfully marketed products. Pre-dissolving drugs in lipids, surfactants, or mixtures of lipids and surfactants omits the dissolving....../dissolution step, which is a potential rate limiting factor for oral absorption of poorly water-soluble drugs. Lipids not only vary in structures and physiochemical properties, but also in their digestibility and absorption pathway; therefore selection of lipid excipients and dosage form has a pronounced effect...

  19. Bioavailability assessment of the lipophilic benfotiamine as compared to a water-soluble thiamin derivative.

    Science.gov (United States)

    Bitsch, R; Wolf, M; Möller, J; Heuzeroth, L; Grüneklee, D

    1991-01-01

    The bioequivalence of thiamin in 2 therapeutically used preparations was tested in 10 healthy young men. Thiamin was orally administered either as lipophilic benfotiamine or as water-soluble thiamin mononitrate. Biokinetic data, measured as area under the curve and maximal concentration in plasma and hemolysate after ingestion, demonstrated a significantly improved bioavailability from the lipophilic derivative despite an ingested dose of only 40% as compared with the water-soluble salt. A superior cellular efficacy of benfotiamine was also concluded from the short-term stimulation of the thiamin-dependent transketolase activity in erythrocytes.

  20. Studeis on the immobilization of water soluble phosphatic fertilizer in some soils with 32P

    International Nuclear Information System (INIS)

    Zhang Yumei; Li Rensheng; Xu Xinyu

    1985-01-01

    Using superphosphate lablled with 32 P, we studied immobilization of water-soluble phosphatic fertilizer on 12 typies of soil. The experimental result showed that major factors to govern immobilization of water-soluble phosphatic fertilizer are: quickly availible Fe that showed positive correlation with the immobilization when it was 4.64-65.72 ppm; and pH that showed negative correlation with the immobilization when it was between 5.35 and 8.88. CaCO 3 and organic matter showed a great effect on the immobilization though there wasn't obvious correlation among them

  1. Lyophilized silica lipid hybrid (SLH) carriers for poorly water-soluble drugs: physicochemical and in vitro pharmaceutical investigations.

    Science.gov (United States)

    Yasmin, Rokhsana; Tan, Angel; Bremmell, Kristen E; Prestidge, Clive A

    2014-09-01

    Lyophilization was investigated to produce a powdery silica-lipid hybrid (SLH) carrier for oral delivery of poorly water-soluble drugs. The silica to lipid ratio, incorporation of cryoprotectant, and lipid loading level were investigated as performance indicators for lyophilized SLH carriers. Celecoxib, a nonsteroidal anti-inflammatory drug, was used as the model poorly soluble moiety to attain desirable physicochemical and in vitro drug solubilization properties. Scanning electron microscopy and confocal fluorescence imaging verified a nanoporous, homogenous internal matrix structures of the lyophilized SLH particles, prepared from submicron triglyceride emulsions and stabilized by porous silica nanoparticles (Aerosil 380), similar to spray-dried SLH. 20-50 wt % of silica in the formulation have shown to produce nonoily SLH agglomerates with complete lipid encapsulation. The incorporation of a cryoprotectant prevented irreversible aggregation of the silica-stabilized droplets during lyophilization, thereby readily redispersing in water to form micrometre-sized particles (water-soluble therapeutics is confirmed. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  2. Novel Water Soluble Chitosan Derivatives with 1,2,3-Triazolium and Their Free Radical-Scavenging Activity

    Directory of Open Access Journals (Sweden)

    Qing Li

    2018-03-01

    Full Text Available Chitosan is an abundant and renewable polysaccharide, which exhibits attractive bioactivities and natural properties. Improvement such as chemical modification of chitosan is often performed for its potential of providing high bioactivity and good water solubility. A new class of chitosan derivatives possessing 1,2,3-triazolium charged units by associating “click reaction” with efficient 1,2,3-triazole quaternization were designed and synthesized. Their free radical-scavenging activity against three free radicals was tested. The inhibitory property and water solubility of the synthesized chitosan derivatives exhibited a remarkable improvement over chitosan. It is hypothesized that triazole or triazolium groups enable the synthesized chitosan to possess obviously better radical-scavenging activity. Moreover, the scavenging activity against superoxide radical of chitosan derivatives with triazolium (IC50 < 0.01 mg mL−1 was more efficient than that of derivatives with triazole and Vitamin C. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH and hydroxyl radical-scavenging assay, the same pattern were observed, which should be related to the triazolium grafted at the periphery of molecular chains.

  3. Relationship Between Urinary Concentrations of Nine Water-soluble Vitamins and their Vitamin Intakes in Japanese Adult Males

    OpenAIRE

    Shibata, Katsumi; Hirose, Junko; Fukuwatari, Tsutomu

    2014-01-01

    Excess water-soluble vitamins are thought to be eliminated in the urine. We have reported a strong relationship between water-soluble vitamin intake and urinary excretion in females. The relationship, however, is not well understood in males. In the present experiment, 10 Japanese male subjects were given a standard Japanese diet for the first week. The subjects remained on the same diet, and a synthesized water-soluble vitamin mixture containing one time the Dietary Reference Intakes (DRIs) ...

  4. Associative, thermodynamic and thermo-kinetics behavior of di- and triblock copolymers of oxyethylene and oxybutylene in aqueous media

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Abbas [Department of Chemistry, Abdul Wali Khan University, Mardan 23200 (Pakistan); Department of Chemistry, Quaid-I-Azam University, Islamabad 45320 (Pakistan); Siddiq, Mohammad, E-mail: m_sidiq12@yahoo.com [Department of Chemistry, Quaid-I-Azam University, Islamabad 45320 (Pakistan)

    2014-11-10

    Highlights: • Associative, thermodynamic and thermo-kinetics behavior was investigated. • Micellization of these copolymer is spontaneous, endothermic and entropy driven. • Micelles are spherical in shape and their nature depends on temperature. • Fusion/fission mechanism dominates over unimer entry/expulsion for micellar dynamics. • Micellar parameters depend on temperature and on the delicate hydrophobic–hydrophilic balance of the blocks. - Abstract: The associative, thermodynamic and thermo-kinetics properties of a diblock E{sub 90}B{sub 10} and three triblock copolymers based on polyoxyethylene and polyoxybutylene of the type E{sub m}B{sub 10}E{sub m} water have been studied by surface tensiometry, light scattering and temperature-jump stopped-flow techniques. The data from surface tension was helpful to detect the critical micelle concentration (CMC) as well as to calculate the thermodynamic parameters of micellization. Dynamic light scattering (DLS) was employed to obtain the values of hydrodynamic radii (R{sub h}), volume (υ{sub h}) and hydrodynamic expansion parameter (δ{sub h}) of the micelle at different temperatures. Similarly, static light scattering (SLS) measurements made us enable to find out various micellar parameters such as; weight-average molar (M{sub w}), association number (N{sub w}), thermodynamic radius (R{sub t}), thermodynamic volume (υ{sub t}), anhydrous volume (υ{sub a}) and thermodynamic expansion parameter (δ{sub t}) of the micelles. Likewise, the kinetics of micellar aggregation/dynamic was also investigated by using temperature-jump stopped-flow technique in the temperature range of 20–50 °C.

  5. Precise Control over the Rheological Behavior of Associating Stimuli-Responsive Block Copolymer Gels

    Directory of Open Access Journals (Sweden)

    Jérémy Brassinne

    2015-12-01

    Full Text Available “Smart” materials have considerably evolved over the last few years for specific applications. They rely on intelligent macromolecules or (supra-molecular motifs to adapt their structure and properties in response to external triggers. Here, a supramolecular stimuli-responsive polymer gel is constructed from heterotelechelic double hydrophilic block copolymers that incorporate thermo-responsive sequences. These macromolecular building units are synthesized via a three-step controlled radical copolymerization and then hierarchically assembled to yield coordination micellar hydrogels. The dynamic mechanical properties of this particular class of materials are studied in shear flow and finely tuned via temperature changes. Notably, rheological experiments show that structurally reinforcing the micellar network nodes leads to precise tuning of the viscoelastic response and yield behavior of the material. Hence, they constitute promising candidates for specific applications, such as mechano-sensors.

  6. Silk-collagen-like block copolymers with charged blocks : self-assembly into nanosized ribbons and macroscopic gels

    NARCIS (Netherlands)

    Martens, A.A.

    2008-01-01

    The research described in this thesis concerns the design, biotechnological production, and physiochemical study of large water-soluble (monodisperse) protein triblock-copolymers with sequential blocks, some of which are positively or negatively charged and self-assemble in response to a change in

  7. A clear coat from a water soluble precursor

    NARCIS (Netherlands)

    Yang, Juan; Bos, Inge; Pranger, Wim; Stuiver, Anthonie; Velders, Aldrik H.; Cohen Stuart, Martien A.; Kamperman, Marleen

    2016-01-01

    Traditional paints consist of hydrophobic polymers dissolved in hydrocarbons; they are appreciated for their rheological properties and the smooth and glossy films they form upon drying and crosslinking, but are now largely banned because of the hazards associated with the solvents. In terms of

  8. Synthesis of phthalocyanines-ALA conjugates: water-soluble compounds with low aggregation.

    Science.gov (United States)

    de Oliveira, Kleber T; de Assis, Francisco F; Ribeiro, Anderson O; Neri, Claudio R; Fernandes, Adjaci U; Baptista, Mauricio S; Lopes, Norberto P; Serra, Osvaldo A; Iamamoto, Yassuko

    2009-10-16

    Syntheses of two water-soluble phthalocyanines (Pc) containing 5-aminolevulinic acid (ALA) linked to the core structure are described. These compounds were prepared by using original functionalizations, and they present remarkable structural and photophysical features, indicating that they could be applied to photodynamic therapy (PDT).

  9. Profiling and relationship of water-soluble sugar and protein compositions in soybean seeds.

    Science.gov (United States)

    Yu, Xiaomin; Yuan, Fengjie; Fu, Xujun; Zhu, Danhua

    2016-04-01

    Sugar and protein are important quality traits in soybean seeds for making soy-based food products. However, the investigations on both compositions and their relationship have rarely been reported. In this study, a total of 35 soybean germplasms collected from Zhejiang province of China, were evaluated for both water-soluble sugar and protein. The total water-soluble sugar (TWSS) content of the germplasms studied ranged from 84.70 to 140.91 mg/g and the water-soluble protein (WSP) content varied from 26.5% to 36.0%. The WSP content showed positive correlations with the TWSS and sucrose contents but negative correlations with the fructose and glucose contents. The clustering showed the 35 germplasms could be divided into four groups with specific contents of sugar and protein. The combination of water-soluble sugar and protein profiles provides useful information for future breeding and genetic research. This investigation will facilitate future work for seed quality improvement. Copyright © 2015. Published by Elsevier Ltd.

  10. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer

    NARCIS (Netherlands)

    Baker, M.B.; Albertazzi, L.; Voets, Ilja K.; Leenders, C.M.A.; Palmans, A.R.A.; Pavan, G.M.; Meijer, E. W.

    2015-01-01

    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers:

  11. pKa Determination of water-soluble calix[4]arenes

    NARCIS (Netherlands)

    Shinkai, Seiji; Araki, Koji; Grootenhuis, P.D.J.; Reinhoudt, David

    1991-01-01

    Neutral, water-soluble 5,11,17,23-tetrakis[bis-(2-hydroxyethyl)aminosulphonyl]calix[4]arene-25,26,27,28-tetraol and 5,11,17,23-tetranitrocalix[4]arene-25,26,27,28-tetraol have been synthesized and the pKa values of the OH groups determined in an aqueous system.

  12. Processes controlling the production of aromatic water-soluble organic matter during litter decomposition

    NARCIS (Netherlands)

    Klotzbücher, T.; Kaiser, K.; Filley, T.R.; Kalbitz, K.

    2013-01-01

    Dissolved organic matter (DOM) plays a fundamental role for many soil processes. For instance, production, transport, and retention of DOM control properties and long-term storage of organic matter in mineral soils. Production of water-soluble compounds during the decomposition of plant litter is a

  13. Fluorescent Water Soluble Polymers for Isozyme-Selective Interactions with Matrix Metalloproteinase-9

    Science.gov (United States)

    Dutta, Rinku; Scott, Michael D.; Haldar, Manas K.; Ganguly, Bratati; Srivastava, D. K.; Friesner, Daniel L.; Mallik, Sanku

    2011-01-01

    Matrix metalloproteinases (MMPs) are overexpressed in various pathological conditions, including various cancers. Although these isozymes have similar active sites, the patterns of exposed amino acids on their surfaces are different. Herein, we report the synthesis and molecular interactions of two water-soluble, fluorescent polymers which demonstrate selective interactions with MMP-9 compared to MMP-7 and -10. PMID:21367603

  14. Testing water-soluble carbohydrate QTL effects in perennial ryegrass (Lolium perenne L.) by marker selection

    NARCIS (Netherlands)

    Turner, L.B.; Farrell, M.; Humphreys, M.O.; Dolstra, O.

    2010-01-01

    Water-soluble carbohydrates (WSC) are an important factor determining the nutritional value of grass forage and development of genetic markers for selection of WSC traits in perennial ryegrass would benefit future breeding programmes. Quantitative trait loci (QTLs) for WSC have been published for an

  15. Antioxidative activity of water soluble polysaccharide in pumpkin fruits (Cucurbita maxima Duchesne).

    Science.gov (United States)

    Nara, Kazuhiro; Yamaguchi, Akira; Maeda, Naomi; Koga, Hidenori

    2009-06-01

    We evaluated the antioxidative activity of a water soluble polysaccharide fraction (WSP) from pumpkin fruits (Cucurbita maxima Duchesne). In the WSP, DPPH radical scavenging and superoxide dismutase-like activity increased depending on the total sugar content. Furthermore, the WSP can serve as an inhibitor of ascorbic acid oxidation. The efficacy was also affected by the total sugar content.

  16. Cross-linking of dermal sheep collagen using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Damink, LHHO; Dijkstra, PJ; vanLuyn, MJA; vanWachem, PB; Nieuwenhuis, P; Feijen, J

    A cross-linking method for collagen-based biomaterials was developed using the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride (EDC). Cross-linking using EDC involves the activation of carboxylic acid groups to give O-acylisourea groups, which form cross-links

  17. In vitro degradation of dermal sheep collagen cross-linked using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Damink, LHHO; Dijkstra, PJ; vanLuyn, MJA; vanWachem, PB; Nieuwenhuis, P; Feijen, J

    Bacterial collagenase was used to study the susceptibility of dermal sheep collagen (DSC) cross-inked with a mixture of the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide (EIN-DSC) towards enzymatic degradation. Contrary to

  18. Cross-linking of dermal sheep collagen using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Olde damink, L.H.H.; Olde Damink, L.H.H.; Dijkstra, Pieter J.; van Luyn, M.J.A.; van Wachem, P.B.; Nieuwenhuis, P.; Feijen, Jan

    1996-01-01

    A cross-linking method for collagen-based biomaterials was developed using the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride (EDC). Cross-linking using EDC involves the activation of carboxylic acid groups to give O-acylisourea groups, which form cross-links

  19. 40 CFR 799.6786 - TSCA water solubility: Generator column method.

    Science.gov (United States)

    2010-07-01

    ... b, using a linear regression equation of C vs. R in the following form: Equation 4: ER15DE00.062... address in paragraph (e) of this section. (b) Introduction—(1) Purpose. (i) The water solubility of a... peak area to volume injected and, from the regression equation of the calibration line, determine the...

  20. Synthesis of water-soluble scaffolds for peptide cyclization, labeling, and ligation

    NARCIS (Netherlands)

    Smeenk, L.E.J.; Dailly, N.; Hiemstra, H.; van Maarseveen, J.H.; Timmerman, P.

    2012-01-01

    The synthesis and applications of water-soluble scaffolds that conformationally constrain side chain unprotected linear peptides containing two cysteines are described. These scaffolds contain a functionality with orthogonal reactivity to be used for labeling and ligation. This is illustrated by the

  1. Kinetics of Acid Hydrolysis of Water-Soluble Spruce O-Acetyl Galactoglucomannans

    NARCIS (Netherlands)

    Xu, C.; Pranovich, A.; Vahasalo, L.; Hemming, J.; Holmbom, B.; Schols, H.A.; Willfor, S.

    2008-01-01

    Water-soluble O-acetyl galactoglucomannan (GGM) is a softwood-derived polysaccharide, which can be extracted on an industrial scale from wood or mechanical pulping waters and now is available in kilogram scale for research and development of value-added products. To develop applications of GGM,

  2. Removal of Water-Soluble Extractives Improves the Enzymatic Digestibility of Steam-Pretreated Softwood Barks.

    Science.gov (United States)

    Frankó, Balázs; Carlqvist, Karin; Galbe, Mats; Lidén, Gunnar; Wallberg, Ola

    2018-02-01

    Softwood bark contains a large amounts of extractives-i.e., soluble lipophilic (such as resin acids) and hydrophilic components (phenolic compounds, stilbenes). The effects of the partial removal of water-soluble extractives before acid-catalyzed steam pretreatment on enzymatic digestibility were assessed for two softwood barks-Norway spruce and Scots pine. A simple hot water extraction step removed more than half of the water-soluble extractives from the barks, which improved the enzymatic digestibility of both steam-pretreated materials. This effect was more pronounced for the spruce than the pine bark, as evidenced by the 30 and 11% glucose yield improvement, respectively, in the enzymatic digestibility. Furthermore, analysis of the chemical composition showed that the acid-insoluble lignin content of the pretreated materials decreased when water-soluble extractives were removed prior to steam pretreatment. This can be explained by a decreased formation of water-insoluble "pseudo-lignin" from water-soluble bark phenolics during the acid-catalyzed pretreatment, which otherwise results in distorted lignin analysis and may also contribute to the impaired enzymatic digestibility of the barks. Thus, this study advocates the removal of extractives as the first step in the processing of bark or bark-rich materials in a sugar platform biorefinery.

  3. Interlaboratory validation of small-scale solubility and dissolution measurements of poorly water-soluble drugs

    DEFF Research Database (Denmark)

    Andersson, Sara B. E.; Alvebratt, Caroline; Bevernage, Jan

    2016-01-01

    The purpose of this study was to investigate the interlaboratory variability in determination of apparent solubility (Sapp) and intrinsic dissolution rate (IDR) using a miniaturized dissolution instrument. Three poorly water-soluble compounds were selected as reference compounds and measured at m...

  4. Distribution of various water soluble radioactive metalloporphyrins in tumor bearing mice

    International Nuclear Information System (INIS)

    Hambright, P.; Fawwaz, R.; Valk, P.; McRae, J.; Bearden, A.J.

    1975-01-01

    The distribution of a variety of water soluble 109 Pd and 64 Cu porphyrins were studied in mice bearing three types of tumors. While the metalloporphyrins are found to have an affinity for neoplastic tissue, substantial extra-tumor concentrations are also noted. Although this limits their value as specific tumor imaging agents, their use in localized therapy is discussed

  5. Wax encapsulation of water-soluble compounds for application in foods.

    Science.gov (United States)

    Mellema, M; Van Benthum, W A J; Boer, B; Von Harras, J; Visser, A

    2006-11-01

    Water-soluble ingredients have been successfully encapsulated in wax using two preparation techniques. The first technique ('solid preparation') leads to relatively large wax particles. The second technique ('liquid preparation') leads to relatively small wax particles immersed in vegetable oil. On the first technique: stable encapsulation of water-soluble colourants (dissolved at low concentration in water) has been achieved making use of beeswax and PGPR. The leakage from the capsules, for instance of size 2 mm, is about 30% after 16 weeks storage in water at room temperature. To form such capsules a minimum wax mass of 40% relative to the total mass is needed. High amounts of salt or acids at the inside water phase causes more leaking, probably because of the osmotic pressure difference. Osmotic matching of inner and outer phase can lead to a dramatic reduction in leakage. Fat capsules are less suitable to incorporate water soluble colourants. The reason for this could be a difference in crystal structure (fat is less ductile and more brittle). On the second technique: stable encapsulation of water-soluble colourants (encapsulated in solid wax particles) has been achieved making use of carnauba wax. The leakage from the capsules, for instance of size 250 mm, is about 40% after 1 weeks storage in water at room temperature.

  6. Assessment of acute toxicity of water soluble fraction of diesel on ...

    African Journals Online (AJOL)

    Acute toxicity of water soluble fraction (WSF) of diesel fuel was assessed by evaluating its effects on growth of two marine microalgae, Isochrysis and Chaetoceros. Pure cultures of each of the two microalgae were exposed to concentrations of 0% (controls), 5%, 10%, 15% and 20% of diesel WSF (in triplicates) and allowed ...

  7. Cross-linking of wheat gluten using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Tropini, V.; Lens, J.P.; Mulder, W.J.; Silvestre, F.

    2000-01-01

    Wheat gluten was cross-linked using water-soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide HCl (EDC). To enhance cross-linking, N-hydroxysuccinimide (NHS) was added to the reaction mixture. The cross-linking efficiency was evaluated by the decrease in the amount of amino groups, the solubility

  8. Amino acids as co-amorphous stabilizers for poorly water soluble drugs--Part 1

    DEFF Research Database (Denmark)

    Löbmann, Korbinian; Grohganz, Holger; Laitinen, Riikka

    2013-01-01

    molecular weight excipients that form specific molecular interactions with the drug resulting in co-amorphous forms. The two poorly water soluble drugs carbamazepine and indomethacin were combined with amino acids from the binding sites of the biological receptors of these drugs. Mixtures of drug...

  9. Mechanisms and Regulation of Intestinal Absorption of Water-soluble Vitamins: Cellular and Molecular Aspects

    DEFF Research Database (Denmark)

    Nexø, Ebba; Said, Hamid M

    2012-01-01

    The water-soluble vitamins represent a group of structurally and functionally unrelated compounds that share the common feature of being essential for normal cellular functions, growth, and development. With the exception of some endogenous production of niacin, human cells cannot synthesize...

  10. The effect of water solubles on Kelvin effects of the Maritime Polluted ...

    African Journals Online (AJOL)

    In this work microphysical properties of Maritime Polluted aerosols wereextracted from Optical Properties of Aerosols and Clouds (OPAC) after varying the concentrations of water soluble at five different levels. The analytical expressions for the changes in the equilibrium relative humidity (RH), effective radii, effective ...

  11. Structural investigation of water-soluble polysaccharides extracted from the fruit bodies of Coprinus comatus

    NARCIS (Netherlands)

    Li, Bo; Dobruchowska, Justyna M.; Gerwig, Gerrit J.; Dijkhuizen, Lubbert; Kamerling, Johannis P.

    2013-01-01

    Water-soluble polysaccharide material, extracted from the stipes of the fruit bodies of Coprinus comatus by hot water, was fractionated by sequential weak anion-exchange and size-exclusion chromatography. The relevant fractions were subjected to structural analysis, including (D/L)

  12. Biphasic and SAPC Hydroformylation Catalyzed by Rh-phosphines Bound to Water-Soluble Polymers

    DEFF Research Database (Denmark)

    Malmstrøm, Torsten; Andersson, Carlaxel; Hjortkjær, Jes

    1999-01-01

    Coupling of the triphenylphosphine moiety to poly-acrylic acid and poly-ethyleneimine respectively afford the macromolecular ligands PAA-PNH and PEI-PNH. Reaction of the ligands with Rh(CO)2(acac) give water-soluble complexes that are active as catalysts in the hydroformylation ofdifferent olefins...

  13. Renal excretion of water-soluble contrast media after enema in the neonatal period.

    Science.gov (United States)

    Kim, Hee Sun; Je, Bo-Kyung; Cha, Sang Hoon; Choi, Byung Min; Lee, Ki Yeol; Lee, Seung Hwa

    2014-08-01

    When abdominal distention occurs or bowel obstruction is suspected in the neonatal period, a water-soluble contrast enema is helpful for diagnostic and therapeutic purposes. The water-soluble contrast medium is evacuated through the anus as well as excreted via the kidneys in some babies. This study was designed to evaluate the incidence of renal excretion after enemas using water-soluble contrast media and presume the causes. Contrast enemas using diluted water-soluble contrast media were performed in 23 patients under 2 months of age. After the enema, patients were followed with simple abdominal radiographs to assess the improvement in bowel distention, and we could also detect the presence of renal excretion of contrast media on the radiographs. Reviewing the medical records and imaging studies, including enemas and consecutive abdominal radiographs, we evaluated the incidence of renal excretion of water-soluble contrast media and counted the stay duration of contrast media in urinary tract, bladder, and colon. Among 23 patients, 12 patients (52%) experienced the renal excretion of water-soluble contrast media. In these patients, stay-in-bladder durations of contrast media were 1-3 days and stay-in-colon durations of contrast media were 1-10 days, while stay-in-colon durations of contrast media were 1-3 days in the patients not showing renal excretion of contrast media. The Mann-Whitney test for stay-in-colon durations demonstrated the later evacuation of contrast media in the patients with renal excretion of contrast media (p = 0.07). The review of the medical records showed that 19 patients were finally diagnosed as intestinal diseases, including Hirschsprung's disease, meconium ileum, meconium plug syndrome, and small bowel atresia or stenosis. Fisher's exact test between the presence of urinary excretion and intestinal diseases indicated a statistically significant difference (p = 0.04). The intestinal diseases causing bowel obstruction may increase the

  14. Water solubility of synthetic pyrope at high temperature and pressure up to 12GPa

    Science.gov (United States)

    Huang, S.; Chen, J.

    2012-12-01

    Water can be incorporated into normally anhydrous minerals as OH- defects and transported into the mantle. Its existence in the mantle may affect property of minerals, such as elasticity, electrical conductivity and rheological properties. As the secondary mineral in the mantle, garnet has not been extensively studied for its water solubility and there is discrepancies among the existing experiments on the water solubility in the garnet change at pressures and temperatures. Geiger et al., 1991 investigated water content in synthetic pyrope and concluded 0.02wt% to 0.07wt% OH- substitution. Lu et al., 1997 found 198ppm water in the Dora Miara pyrope at 100Kbar and 1000°C. Withers et al., 1998 claimed that water solubility in pyrope reached 1000ppm at 5GPa and then decreased as pressure increasing; above 7GPa, no water was detected. Mookherjee et al., 2009 also explored pyrope-rich garnet, which contains water up to 0.1%wt at 5-9GPa and temperatures 1373K-1473K. Here we report a study of water solubility of synthetic single crystal pyrope at pressures 4-12GPa and temperature 1000°C. Single crystals of pyrope were synthesized using multi-anvil press and water contents in these samples were measured using FTIR. We have observed OH- peak at 3650 cm-1 along this pressure range, although Withers, 1998 reported water contents decrease to undetectable level above 7GPa. Water solubility in pyrope will be reported as a function of pressure up to 12 GPa at 1000°C.

  15. Self-Assembly of Charged Amphiphilic Diblock Copolymers with Insoluble Blocks of Decreasing Hydrophobicity: From Kinetically Frozen Colloids to Macrosurfactants

    Energy Technology Data Exchange (ETDEWEB)

    M Jacquin; P Muller; H Cottet; O Theodoly

    2011-12-31

    We have investigated the self-assembly properties in aqueous solution of amphiphilic diblock copolymers with insoluble blocks of different hydrophobicity and demonstrated that the condition to obtain dynamic micelles is to design samples with insoluble blocks of low enough hydrophobicity. We focus here on results with new water-soluble amphiphilic diblock copolymers poly(diethyleneglycol ethylether acrylate)-b-poly(acrylic acid), or PDEGA-b-PAA. The physical characteristics of PDEGA-b-PAA micelles at high ionization have been determined by small angle neutron scattering (SANS). We show that PDEGA-b-PAA samples form micelles at thermodynamic equilibrium. The critical micelle concentrations (CMCs) decrease strongly with ionic strength and temperature due to a solvent quality decrease for, respectively, the corona and the core. This behavior of reversible aggregation is remarkable as compared to the behavior of kinetically frozen aggregation that has been widely observed with samples of similar architecture and different hydrophobic blocks, for example, poly(styrene)-b-poly(acrylic acid), PS-b-PAA, and poly(butyl acrylate)-b-poly(acrylic acid), PBA-b-PAA. We have measured the interfacial tension between water and the homopolymers PDEGA and PBA at, respectively, 3 and 20 mN/m at room temperature, which permits one to estimate the energy cost to extract a unimer from a micelle. The results are consistent with a micelle association that is fast for PDEGA-b-PAA and kinetically frozen PBA-b-PAA. Hence, PDEGA-b-PAA samples form a new system of synthetic charged macrosurfactant with unique properties of fast dynamic association, tunable charge, and water solubility even at temperatures and NaCl concentrations as high as 65 C and 1 M.

  16. Recording ion channels across soy-extracted lecithin bilayer generated by water-soluble quantum dots

    Science.gov (United States)

    Sarma, Runjun; Mohanta, Dambarudhar

    2014-02-01

    We report on the quantum dot (QD)-induced ion channels across a soya-derived lecithin bilayer supported on a laser drilled of ~100 μm aperture of cellulose acetate substrate that separates two electrolytic chambers. Adequate current bursts were observed when the bilayer was subjected to a gating voltage. The voltage-dependent current fluctuation, across the bilayer, was attributed to the insertion of ~20 nm sized water-soluble CdSe QDs, forming nanopores due to their spontaneous aggregation. Apart from a closed state, the first observable conductance levels were found as 6.3 and 11 nS, as for the respective biasing voltages of -10 and -20 mV. The highest observable conductance states, at corresponding voltages were ~14.3 and 21.1 nS. Considering two simplified models, we predict that the non-spherical pores (dnspore) can be a better approximation over spherical nanopores (dspore) for exhibiting a definite conductance level. At times, even dnspore ≤ 4dspore and that the non-spherical nanopores were associated with a smaller No. of QDs than the case for spherical nanopores, for a definite conductance state. It seems like the current events are partly stochastic, possibly due to thermal effects on the aggregated QDs that would form nanopores. The dwell time of the states was predicted in the range of 384-411 μs. The ion channel mechanism in natural phospholipid bilayers over artificial ones will provide a closer account to understand ion transport mechanism in live cells and signaling activity including labelling with fluorescent QDs.

  17. Wintertime water-soluble aerosol composition and particle water content in Fresno, California

    Science.gov (United States)

    Parworth, Caroline L.; Young, Dominique E.; Kim, Hwajin; Zhang, Xiaolu; Cappa, Christopher D.; Collier, Sonya; Zhang, Qi

    2017-03-01

    The composition and concentrations of water-soluble gases and ionic aerosol components were measured from January to February 2013 in Fresno, CA, with a particle-into-liquid sampler with ion chromatography and annular denuders. The average (±1σ) ionic aerosol mass concentration was 15.0 (±9.4) µg m-3, and dominated by nitrate (61%), followed by ammonium, sulfate, chloride, potassium, nitrite, and sodium. Aerosol-phase organic acids, including formate and glycolate, and amines including methylaminium, triethanolaminium, ethanolaminium, dimethylaminium, and ethylaminium were also detected. Although the dominant species all came from secondary aerosol formation, there were primary sources of ionic aerosols as well, including biomass burning for potassium and glycolate, sea spray for sodium, chloride, and dimethylamine, and vehicles for formate. Particulate methanesulfonic acid was also detected and mainly associated with terrestrial sources. On average, the molar concentration of ammonia was 49 times greater than nitric acid, indicating that ammonium nitrate formation was limited by nitric acid availability. Particle water was calculated based on the Extended Aerosol Inorganics Model (E-AIM) thermodynamic prediction of inorganic particle water and κ-Köhler theory approximation of organic particle water. The average (±1σ) particle water concentration was 19.2 (±18.6) µg m-3, of which 90% was attributed to inorganic species. The fractional contribution of particle water to total fine particle mass averaged at 36% during this study and was greatest during early morning and night and least during the day. Based on aqueous-phase concentrations of ions calculated by using E-AIM, the average (±1σ) pH of particles in Fresno during the winter was estimated to be 4.2 (±0.2).

  18. Spectroscopic evidence of xanthine compounds fluorescence quenching effect on water-soluble porphyrins

    Science.gov (United States)

    Makarska-Bialokoz, Magdalena

    2015-02-01

    The formation of π-stacked complexes between water-soluble porphyrins: 4,4‧,4″,4″‧-(21H,23H-porphine-5,10,15,20-tetrayl)tetrakis-(benzoic acid) (H2TCPP), 5,10,15,20-tetrakis(4-sulfonatophenyl)-21H,23H-porphine (H2TPPS4), 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H2TTMePP), 5,10,15,20-tetrakis(1-methyl-4-pyridyl)-21H,23H-porphine tetra-p-tosylate (H2TMePyP), the Cu(II) complexes of H2TTMePP and H2TMePyP, as well as chlorophyll a with xanthine, theophylline (1,3-dimethylxanthine) and theobromine (3,7-dimethylxanthine) has been studied analysing their absorption and steady-state fluorescence spectra in aqueous (or acetone in case of chlorophyll a) solution. During titration by the compounds from xanthine group the bathochromic effect in the porphyrin absorption spectra as well as the hypochromicity of the porphyrin Soret maximum can be noticed. The fluorescence quenching effect observed during interactions in the systems examined suggests the process of static quenching. The association and fluorescence quenching constants are of the order of magnitude of 103 - 102 mol-1. The results obtained show that xanthine and its derivatives can quench the fluorescence of the porphyrins according to the number of methyl groups in the molecule of quencher.

  19. Ubiquitous water-soluble molecules in aquatic plant exudates determine specific insect attraction.

    Directory of Open Access Journals (Sweden)

    Julien Sérandour

    Full Text Available Plants produce semio-chemicals that directly influence insect attraction and/or repulsion. Generally, this attraction is closely associated with herbivory and has been studied mainly under atmospheric conditions. On the other hand, the relationship between aquatic plants and insects has been little studied. To determine whether the roots of aquatic macrophytes release attractive chemical mixtures into the water, we studied the behaviour of mosquito larvae using olfactory experiments with root exudates. After testing the attraction on Culex and Aedes mosquito larvae, we chose to work with Coquillettidia species, which have a complex behaviour in nature and need to be attached to plant roots in order to obtain oxygen. This relationship is non-destructive and can be described as commensal behaviour. Commonly found compounds seemed to be involved in insect attraction since root exudates from different plants were all attractive. Moreover, chemical analysis allowed us to identify a certain number of commonly found, highly water-soluble, low-molecular-weight compounds, several of which (glycerol, uracil, thymine, uridine, thymidine were able to induce attraction when tested individually but at concentrations substantially higher than those found in nature. However, our principal findings demonstrated that these compounds appeared to act synergistically, since a mixture of these five compounds attracted larvae at natural concentrations (0.7 nM glycerol, <0.5 nM uracil, 0.6 nM thymine, 2.8 nM uridine, 86 nM thymidine, much lower than those found for each compound tested individually. These results provide strong evidence that a mixture of polyols (glycerol, pyrimidines (uracil, thymine, and nucleosides (uridine, thymidine functions as an efficient attractive signal in nature for Coquillettidia larvae. We therefore show for the first time, that such commonly found compounds may play an important role in plant-insect relationships in aquatic eco-systems.

  20. Water soluble poly(styrene sulfonate)-b-poly(vinylidene fluoride)-b-poly(styrene sulfonate) triblock copolymer nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Černoch, Peter; Černochová, Zulfiya; Petrova, Svetlana; Kaňková, Dana; Kim, J.-S.; Vasu, V.; Asandei, A. D.

    2016-01-01

    Roč. 6, č. 60 (2016), s. 55374-55381 ISSN 2046-2069 R&D Projects: GA MŠk(CZ) LH14038 Institutional support: RVO:61389013 Keywords : polystyrenesulfonate * poly(neopentyl styrenesulfonate) * PVDF Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.108, year: 2016

  1. SYNTHESIS AND PHYSICAL-CHEMICAL PROPERTIES OF WATER-SOLUBLE 3-BENZYLXANTHINE DERIVATIVES

    Directory of Open Access Journals (Sweden)

    K. V. Аleksandrova

    2015-04-01

    Full Text Available Introduction Nowadays, research of novel biological active compounds with low toxicity, are carried out among different classes of organic compounds of natural and synthetic genesis. One of the main ways of these studies is search of water-soluble compounds – convenient objects for pharmacological researches. In recent years researchers paid attention to xanthine derivatives, because of their high variativity of possible chemical modification and ability to form different salts with wide spectrum of biological action. Thus, among water-soluble xanthine derivatives were found compounds with pronounced antioxidant, diuretic and analeptic properties. Primary methods of obtaining water-soluble xanthine derivatives are direct interaction of bases with xanthine molecule or insertion basic or acidic residues in positions 7 or 8 of xanthine bicycle. According from the above, search of biologically active compounds among water-soluble substituted xanthines is prospective and actual. The aim of the study was development of synthetic ways of obtaining novel water-soluble derivatives of 3-benzyl-8-methylxanthine and studying their physical and chemical properties. Material and methods Melting points of obtained compounds were determined by capillary method on PTP (M device. ІR-spectra of synthesized compounds were recorded on the Bruker Alpha device (company «Bruker» – Germany on 4000-400 sm-1 with using console ATR (direct insertion of compound. 1Н NMR-spectra were recorded on the Varian Mercury VX-200 device (company «Varian» – USA solvent – (DMSO-d6, internal standart – ТМС. Elemental analysis was made on Elementar Vario L cube device. Chromatoraphic studies were made on the plates Sorbfil-AFV-UV (company «Sobrpolimer» –Russia. Systhems for chromatography: «acetone-propanol-2» in ratio 2:3, «propanol-2-benzene» in ratio 10:1 and exersized in UV-light in wave 200-300 nm. Results and discussion We developed methodic of synthesis

  2. Intestinal absorption of water-soluble vitamins in health and disease.

    Science.gov (United States)

    Said, Hamid M

    2011-08-01

    Our knowledge of the mechanisms and regulation of intestinal absorption of water-soluble vitamins under normal physiological conditions, and of the factors/conditions that affect and interfere with theses processes has been significantly expanded in recent years as a result of the availability of a host of valuable molecular/cellular tools. Although structurally and functionally unrelated, the water-soluble vitamins share the feature of being essential for normal cellular functions, growth and development, and that their deficiency leads to a variety of clinical abnormalities that range from anaemia to growth retardation and neurological disorders. Humans cannot synthesize water-soluble vitamins (with the exception of some endogenous synthesis of niacin) and must obtain these micronutrients from exogenous sources. Thus body homoeostasis of these micronutrients depends on their normal absorption in the intestine. Interference with absorption, which occurs in a variety of conditions (e.g. congenital defects in the digestive or absorptive system, intestinal disease/resection, drug interaction and chronic alcohol use), leads to the development of deficiency (and sub-optimal status) and results in clinical abnormalities. It is well established now that intestinal absorption of the water-soluble vitamins ascorbate, biotin, folate, niacin, pantothenic acid, pyridoxine, riboflavin and thiamin is via specific carrier-mediated processes. These processes are regulated by a variety of factors and conditions, and the regulation involves transcriptional and/or post-transcriptional mechanisms. Also well recognized now is the fact that the large intestine possesses specific and efficient uptake systems to absorb a number of water-soluble vitamins that are synthesized by the normal microflora. This source may contribute to total body vitamin nutrition, and especially towards the cellular nutrition and health of the local colonocytes. The present review aims to outline our current

  3. [HYGIENIC ASSESSMENT OF WATER-SOLUBLE VITAMINS CONTENT IN THE FOOD RATION OF ADOLESCENTS].

    Science.gov (United States)

    Kozubenko, O V; Turchaninov, D V; Boyarskaya, L A; Glagoleva, O N; Pogodin, I S; Luksha, E A

    2015-01-01

    Adequate, balanced nutrition is a precondition for the formation of health of the younger generation. The study of the dietary intake and peculiarities of the chemical composition offood is needed to substantiate measures aimed at the correction of the ration of adolescents. Hygienic evaluation of the content of water soluble vitamins in foods and the ration of teenage population of the Omsk region. TASKS OF THE STUDY: 1. To determine levels of water-soluble vitamins content in foods forming the basis of the ration of the population the Omsk region. 2. On the base of a study of the actual nutrition of adolescents to determine the levels of water-soluble vitamins consumption. 3. To give a hygienic assessment of adolescent nutrition in the Omsk region in terms of provision with water-soluble vitamins, and to identify priority directions of the alimentary correction of the revealed disorders. The analysis of 389 food samples for the content of water-soluble vitamins (B1, B2, B6, PP C, folic acid) was performed with the use of reversed-phase HPLC high pressure on the Shimadzu LC-20 Prominence detector. The hygienic assessment of the actual nutrition of adolescents aged 13-17 years (sample survey; n = 250; 2012-2014) in the Omsk region was performed by the method of the analysis of food consumption frequency. There were noted significantly lower concentrations of vitamin B1 and B2 in the studied samples of cereals, bread and vegetables in comparison with reference data. Consumption levels of vitamins B1, B2, PP folic acid in the diet of adolescents in the Omsk region are lower than recommended values. In the structure of nutrition there is not enough milk dairy products--in 82.4 ± 2.4%, fish and sea products in 90.8 ± 1.8% of adolescents. The actual nutrition of the adolescent population of the Omsk region is irrational, unbalanced in quantitative and qualitative terms, and does not provide the necessary level of consumption of most important water-soluble vitamins

  4. Synthesis of Graft Copolymers Based on Poly(2‐Methoxyethyl Acrylate) and Investigation of the Associated Water Structure

    DEFF Research Database (Denmark)

    Javakhishvili, Irakli; Tanaka, Masaru; Ogura, Keiko

    2012-01-01

    Graft copolymers composed of poly(2‐methoxyethyl acrylate) are prepared employing controlled radical polymerization techniques. Linear backbones bearing atom transfer radical polymerization (ATRP) initiating sites are obtained by reversible addition–fragmentation chain transfer copolymerization...... polydispersity indices (1.17–1.38) are attained. Thermal investigations of the graft copolymers indicate the presence of the freezing bound water, and imply that the materials may exhibit blood compatibility....

  5. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer.

    Science.gov (United States)

    Baker, Matthew B; Albertazzi, Lorenzo; Voets, Ilja K; Leenders, Christianus M A; Palmans, Anja R A; Pavan, Giovanni M; Meijer, E W

    2015-02-20

    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers: one with and one without a stereogenic methyl. Initially aiming simply to understand the molecular behaviour of these systems in water, we find that while the fibres may look identical, the introduction of homochirality imparts a higher level of internal order to the supramolecular polymer. Although this increased order does not seem to affect the basic dimensions of the supramolecular fibres, the equilibrium dynamics of the polymers differ by almost an order of magnitude. This report represents the first observation of a structure/property relationship with regard to equilibrium dynamics in water-soluble supramolecular polymers.

  6. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer

    Science.gov (United States)

    Baker, Matthew B.; Albertazzi, Lorenzo; Voets, Ilja K.; Leenders, Christianus M. A.; Palmans, Anja R. A.; Pavan, Giovanni M.; Meijer, E. W.

    2015-02-01

    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers: one with and one without a stereogenic methyl. Initially aiming simply to understand the molecular behaviour of these systems in water, we find that while the fibres may look identical, the introduction of homochirality imparts a higher level of internal order to the supramolecular polymer. Although this increased order does not seem to affect the basic dimensions of the supramolecular fibres, the equilibrium dynamics of the polymers differ by almost an order of magnitude. This report represents the first observation of a structure/property relationship with regard to equilibrium dynamics in water-soluble supramolecular polymers.

  7. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    Directory of Open Access Journals (Sweden)

    Qing-Xi Wu

    2014-12-01

    Full Text Available Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail.

  8. Design of chitosan and its water soluble derivatives-based drug carriers with polyelectrolyte complexes.

    Science.gov (United States)

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-12-19

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail.

  9. Synthesis and characterization of a hyper-branched water-soluble β-cyclodextrin polymer

    Directory of Open Access Journals (Sweden)

    Francesco Trotta

    2014-11-01

    Full Text Available A new hyper-branched water-soluble polymer was synthesized by reacting β-cyclodextrin with pyromellitic dianhydride beyond the critical conditions that allow the phenomenon of gelation to occur. The molar ratio between the monomers is a crucial parameter that rules the gelation process. Nevertheless, the concentration of monomers in the solvent phase plays a key role as well. Hyper-branched β-cyclodextrin-based polymers were obtained performing the syntheses with excess of solvent and cross-linking agent, and the conditions for critical dilution were determined experimentally. A hyper-branched polymer with very high water solubility was obtained and fully characterized both as for its chemical structure and for its capability to encapsulate substances. Fluorescein was used as probe molecule to test the complexation properties of the new material.

  10. Formation of water-soluble soybean polysaccharides from spent flakes by hydrogen peroxide treatment

    DEFF Research Database (Denmark)

    Pierce, Brian; Wichmann, Jesper; Tran, Tam H.

    2016-01-01

    70% of the original insoluble material as high molar mass soluble polysaccharides. A design of experiment was used to quantify the effects of pH, reaction time, and hydrogen peroxide concentration on the reaction yield, average molar mass, and free monosaccharides generated. The resulting product......In this paper we propose a novel chemical process for the generation of water-soluble polysaccharides from soy spent flake, a by-product of the soy food industry. This process entails treatment of spent flake with hydrogen peroxide at an elevated temperature, resulting in the release of more than...... is low in protein, fat, and minerals and contains predominantly water-soluble polysaccharides of high molar mass, including arabinan, type I arabinogalactan, homogalacturonan, xyloglucan, rhamnogalacturonan, and (glucurono)arabinoxylan. This treatment provides a straightforward approach for generation...

  11. Method of cross-linking polyvinyl alcohol and other water soluble resins

    Science.gov (United States)

    Phillipp, W. H.; May, C. E.; Hsu, L. C.; Sheibley, D. W. (Inventor)

    1980-01-01

    A self supporting sheet structure comprising a water soluble, noncrosslinked polymer such as polyvinyl alcohol which is capable of being crosslinked by reaction with hydrogen atom radicals and hydroxyl molecule radicals is contacted with an aqueous solution having a pH of less than 8 and containing a dissolved salt in an amount sufficient to prevent substantial dissolution of the noncrosslinked polymer in the aqueous solution. The aqueous solution is then irradiated with ionizing radiation to form hydrogen atom radicals and hydroxyl molecule radicals and the irradiation is continued for a time sufficient to effect crosslinking of the water soluble polymer to produce a water insoluble polymer sheet structure. The method has particular application in the production of battery separators and electrode envelopes for alkaline batteries.

  12. Tainting by short-term exposure of Atlantic salmon to water soluble petroleum hydrocarbons

    International Nuclear Information System (INIS)

    Ackman, R.G.; Heras, H.

    1992-01-01

    Experiments were conducted to examine the extent of tainting of salmon by exposure to the soluble fraction of petroleum hydrocarbons. The experiments were conducted on Atlantic salmon in tanks containing seawater artificially contaminated at three different concentrations with the soluble fraction of a North Sea crude. The salmon flesh was analyzed by gas chromatography and taste tests were conducted on cooked salmon samples to determine the extent of tainting. Salmon in control tanks with uncontaminated seawater had muscle accumulations of total hydrocarbons of ca 1 ppM. The muscle accumulations of total hydrocarbons in the salmon were 13.5 ppM, 25.6 ppM, and 31.3 ppM for water soluble fraction concentrations of 0.45, 0.87, and 1.54 ppM respectively. The threshold for taint was clearly inferred to be less than 0.45 ppM of water soluble fraction. 18 refs., 2 figs

  13. Analytical procedures for water-soluble vitamins in foods and dietary supplements: a review.

    Science.gov (United States)

    Blake, Christopher J

    2007-09-01

    Water-soluble vitamins include the B-group vitamins and vitamin C. In order to correctly monitor water-soluble vitamin content in fortified foods for compliance monitoring as well as to establish accurate data banks, an accurate and precise analytical method is a prerequisite. For many years microbiological assays have been used for analysis of B vitamins. However they are no longer considered to be the gold standard in vitamins analysis as many studies have shown up their deficiencies. This review describes the current status of analytical methods, including microbiological assays and spectrophotometric, biosensor and chromatographic techniques. In particular it describes the current status of the official methods and highlights some new developments in chromatographic procedures and detection methods. An overview is made of multivitamin extractions and analyses for foods and supplements.

  14. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    Science.gov (United States)

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-01-01

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail. PMID:25532565

  15. Application of radiation grafting techniques to prepare the high molecular weight water-soluble polymer

    International Nuclear Information System (INIS)

    Le Hai; Nguyen Quoc Hien; Nguyen Tan Man; Truong Thi Hanh; Le Huu Tu; Tran Thi Tam; Pham Thi Sam; Pham Anh Tuan; Le Dinh Lang

    2003-01-01

    The results of the study on the preparation of the high molecular weight water-soluble polymers by radiation grafting and their properties is presented as follows: 1/ by radiation grafting, the molecular weight of PVA was increased 20 times and PAM was increased only 3 times; 2/ the thermal and medium stability of poly(vinyl alcohol) grafted with acrylamide was obviously improved. (LH)

  16. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    OpenAIRE

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-01-01

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have...

  17. Natural polymers: Best carriers for improving bioavailability of poorly water soluble drugs in solid dispersions

    OpenAIRE

    Sandip Sapkal; Mahesh Narkhede; Mukesh Babhulkar; Gautam Mehetre; Ashish Rathi

    2013-01-01

    ABSTRACTNatural polymers and its modified forms can be used as best alternative for improving bioavailabilityof poorly water soluble drugs in solid dispersion. Most of the natural polymersare hydrophilic and having high swelling capacity. Recent trend towards the use of naturalpolymer demands the replacement of synthetic additives with natural ones. Many plant derivednatural polymers are studied for use in solid dispersion systems, out of which naturalgums, cyclodextrin and carbohydrate are m...

  18. IMPROVEMENT OF SOLUBILITY OF BADLY WATER SOLUBLE DRUG (IBUPROFEN) BY USING SURFACTANTS AND CARRIERS

    OpenAIRE

    Md. Zakaria Faruki*, Rishikesh, Elizabeth Razzaque, Mohiuddin Ahmed Bhuiyan

    2013-01-01

    ABSTRACT: Although there was a great interest in solid dispersion systems during the past four decades to increase dissolution rate and bioavailability of badly water-soluble drugs, their profitable use has been very limited, primarily because of manufacturing difficulties and stability problems. In this study solid solutions of drugs were generally produced by fusion method. The drug along with the excipients (surfactants and carriers) was heated first and then hardened by cooling to room te...

  19. Indirect caudal lymphography using a new water-soluble contrast agent - animal experimental studies in pigs

    International Nuclear Information System (INIS)

    Apitzsch, D.E.; Kroll, H.U.; Zuehlke, H.V.

    1981-01-01

    Animal experiments on caudal lymphography in pigs are presented, using a new water-soluble contrast medium which is renally excreted. Indirect cutaneous administration renders possible the radiological visualization of the entire lymphatic drainage system of the lower limb, the retro-peritoneal space and the thoracic duct. Visualization of the lymphatic system is rapid, homogeneous and can be repeated as often as desired. The quality of the lymphogram is as good as that obtained by the current methods in common use. (orig.)

  20. Changing oxidoreduction potential to improve water-soluble yellow pigment production with Monascus ruber CGMCC 10910.

    Science.gov (United States)

    Huang, Tao; Tan, Hailing; Lu, Fangju; Chen, Gong; Wu, Zhenqiang

    2017-11-21

    Monascus pigments are widely used in the food and pharmaceutical industries due to their safety to human health. Our previous study found that glucose concentration induced extracellular oxidoreduction potential (ORP) changes could influence extracellular water-soluble yellow pigment production by Monascus ruber CGMCC 10910 in submerged fermentation. In this study, H 2 O 2 and dithiothreitol (DTT) were used to change the oxidoreduction potential for investigating the effects of oxidative or reductive substances on Monascus yellow pigment production by Monascus ruber CGMCC 10910. The extracellular ORP could be controlled by H 2 O 2 and DTT. Both cell growth and extracellular water-soluble yellow pigment production were enhanced under H 2 O 2 -induced oxidative (HIO) conditions and were inhibited under dithiothreitol-induced reductive conditions. By optimizing the amount of H 2 O 2 added and the timing of the addition, the yield of extracellular water-soluble yellow pigments significantly increased and reached a maximum of 209 AU, when 10 mM H 2 O 2 was added on the 3rd day of fermentation with M. ruber CGMCC 10910. Under HIO conditions, the ratio of NADH/NAD+ was much lower than that in the control group, and the expression levels of relative pigment biosynthesis genes were up-regulated; moreover, the activity of glucose-6-phosphate dehydrogenase (G6PDH) was increased while 6-phosphofructokinase (PFK) activity was inhibited. Oxidative conditions induced by H 2 O 2 increased water-soluble yellow pigment accumulation via up-regulation of the expression levels of relative genes and by increasing the precursors of pigment biosynthesis through redirection of metabolic flux. In contrast, reductive conditions induced by dithiothreitol inhibited yellow pigment accumulation. This experiment provides a potential strategy for improving the production of Monascus yellow pigments.

  1. Biosynthetic Studies on Water-Soluble Derivative 5c (DTX5c

    Directory of Open Access Journals (Sweden)

    José J. Fernández

    2012-10-01

    Full Text Available The dinoflagellate Prorocentrum belizeanum is responsible for the production of several toxins involved in the red tide phenomenon known as Diarrhetic Shellfish Poisoning (DSP. In this paper we report on the biosynthetic origin of an okadaic acid water-soluble ester derivative, DTX5c, on the basis of the spectroscopical analysis of 13C enriched samples obtained by addition of labelled sodium [l-13C], [2-13C] acetate to artificial cultures of this dinoflagellate.

  2. Effect of New Water-Soluble Dendritic Phthalocyanines on Human Colorectal and Liver Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Ebru YABAŞ

    2017-08-01

    Full Text Available Human hepatocellular carcinoma (HepG2 cells and colorectal adenocarcinoma (DLD-1 cells were treated with the synthesized water soluble phthalocyanine derivatives to understand the effect of the compounds both on colorectal and liver cancer cells. The compounds inhibited cell proliferation and displayed cytotoxic effect on these cancer cell lines however; the effect of the compounds on healthy control fibroblast cell line was comparatively lower. The compounds can be employed for cancer treatment as anticancer agents.

  3. Synthesis of gold nanoclusters: a fluorescent marker for water-soluble TiO2 nanotubes

    International Nuclear Information System (INIS)

    Ratanatawanate, Chalita; Yu Jing; Zhou Chen; Zheng Jie; Balkus, Kenneth J Jr

    2011-01-01

    The first example of a water-soluble wrapped titania nanotube (TNT) decorated with fluorescent gold nanoparticles has been prepared. Gold nanoparticles ∼ 1.6 nm in diameter were grown on the TiO 2 nanotubes using a thiolactic acid linker to control the size. The gold clusters emit at 660 nm in water and were imaged using confocal microscopy. The gold decorated TNTs were suspended in water by wrapping the nanotubes with poly-L-arginine.

  4. Preparation and characterization of complexes of RE3+ with furfural modified water-soluble chitosan

    Institute of Scientific and Technical Information of China (English)

    WANG Maoyuan; QIU Ligan; MA Guilin

    2008-01-01

    Degraded chitosan, with highly water-solubility, was obtained by the oxidation of chitosan with H2O2, and then reacted with furfural The final product coordinated with the rare earth ions (RE3+ = Sm3+,Eu3+), which led to the formation of the complexes. The prepared complexes were characterized with Inflated Spectroscopy (IR), Ultra Violet (UV), fluorescence, X-Ray Diffraction (XRD), and Thermogravimetric-Differential Scanning Calorimetry (TG-DSC) measurements.

  5. Improvement of humidity resistance of water soluble core by precipitation method

    Directory of Open Access Journals (Sweden)

    Zhang Long

    2011-05-01

    Full Text Available Water soluble core has been widely used in manufacturing complex metal components with hollow configurations or internal channels; however, the soluble core can absorb water easily from the air at room temperature. To improve the humidity resistance of the water soluble core and optimize the process parameters applied in manufacturing of the water soluble core, a precipitation method and a two-level-three-full factorial central composite design were used, respectively. The properties of the cores treated by the precipitation method were compared with that without any treatment. Through a systematical study by means of both an environmental scanning electron microscope (ESEM and an energy dispersive X-ray (EDX analyzer, the results indicate that the hygroscopicity can be reduced by 20% and the obtained optimal process conditions for three critical control factors affecting the hygroscopicity are 0.2 g·mL-1 calcium chloride concentration, 4% water concentration and 0 min ignition time. The porous surface coated by calcium chloride and the high humidity resistance products generated in the precipitation reaction between calcium chloride and potassium carbonate may contribute to the lower hygroscopicity.

  6. Application To Bilayer System With Water-Soluble Contrast Enhancing Material

    Science.gov (United States)

    Yabuta, Mitsuo; Ito, Naoki; Yamazaki, Hiroyuki; Nakayama, Toshimasa

    1987-09-01

    We have developed ,a water-soluble contrast enhancing material, TAD-436 ( Tokyo Ohka. Anti-Defocus Material ) which is consisted of a water-soluble diazonium salt as bleaching compounds and a water-soluble anion type polymer as binder polymers. Needless to say that water is used as solvent in TAD; therefore, it can be spincoated directly on a positive photoresist layer of a quinonediazide-novolak resin type without causing intermixing and furtheremore the bilayer can be developed without stripping TAD immediately after exposure. TAD shows a satisfactory bleaching characteristics on g-line, increases r-value of underlying photoresist and reduces the thickness loss of photoresist layer in unexposed area. Application to bilayer system with TAD will raise the resolution of underlying photoresist and when the focus depth is changed it will make the change in the resist profile small. As the result of it, the notches in the resist patterns on steps is reduced, making the difference in the linewidth between the top and the bottom of steps small.

  7. Studies on Dissolution Enhancement of Prednisolone, a Poorly Water-Soluble Drug by Solid Dispersion Technique

    Directory of Open Access Journals (Sweden)

    Parvin Zakeri-Milani

    2011-06-01

    Full Text Available Introduction: Prednisolone is a class II substance according to the Biopharmaceutics Classification System. It is a poorly water soluble agent. The aim of the present study was to improve dissolution rate of a poorly water-soluble drug, prednisolone, by a solid dispersion technique. Methods: Solid dispersion of prednisolone was prepared with PEG 6000 or different carbohydrates such as lactose and dextrin with various ratios of the drug to carrier i.e., 1:10, 1:20 and 1:40. Solid dispersions were prepared by coevaporation method. The evaluation of the properties of the dispersions was performed using dissolution studies, Fourier-transform infrared spectroscopy and x-ray powder diffractometery. Results: The results indicated that lactose is suitable carriers to enhance the in vitro dissolution rate of prednisolone. The data from the x-ray diffraction showed that the drug was still detectable in its solid state in all solid dispersions except solid dispersions prepared by dextrin as carrier. The results from infrared spectroscopy showed no well-defined drug–carrier interactions for coevaporates. Conclusion: Solid dispersion of a poorly water-soluble drug, prednisolone may alleviate the problems of delayed and inconsistent rate of dissolution of the drug.

  8. Synthesis of water soluble glycine capped silver nanoparticles and their surface selective interaction

    International Nuclear Information System (INIS)

    Agasti, Nityananda; Singh, Vinay K.; Kaushik, N.K.

    2015-01-01

    Highlights: • Synthesis of water soluble silver nanoparticles at ambient reaction conditions. • Glycine as stabilizing agent for silver nanoparticles. • Surface selective interaction of glycine with silver nanoparticles. • Glycine concentration influences crystalinity and optical property of silver nanoparticles. - Abstract: Synthesis of biocompatible metal nanoparticles has been an area of significant interest because of their wide range of applications. In the present study, we have successfully synthesized water soluble silver nanoparticles assisted by small amino acid glycine. The method is primarily based on reduction of AgNO 3 with NaBH 4 in aqueous solution under atmospheric air in the presence of glycine. UV–vis spectroscopy, transmission electron microscopy (TEM), X–ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG) and differential thermal analysis (DTA) techniques used for characterization of resulting silver nanoparticles demonstrated that, glycine is an effective capping agent to stabilize silver nanoparticles. Surface selective interaction of glycine on (1 1 1) face of silver nanoparticles has been investigated. The optical property and crystalline behavior of silver nanoparticles were found to be sensitive to concentration of glycine. X–ray diffraction studies ascertained the phase specific interaction of glycine on silver nanoparticles. Silver nanoparticles synthesized were of diameter 60 nm. We thus demonstrated an efficient synthetic method for synthesis of water soluble silver nanoparticles capped by amino acid under mild reaction conditions with excellent reproducibility

  9. Spatial and temporal variability of water soluble carbon for a cropped field

    International Nuclear Information System (INIS)

    Liss, H.J.; Rolston, D.E.

    1983-01-01

    The water soluble carbon from soil extracts was taken from a two-hundred point grid established on a 1.2 ha field. The sampling was in the fall after the harvest of a sorghum crop. The concentrations ranged from 23.8 ppm to 274.2 ppm. Over 90 per cent of the concentrations were grouped around the mean of 40.3 ppm. The higher values caused the distribution to be greatly skewed such that neither normal nor log normal distributions characterized the data very well. The moisture content from the same samples followed normal distribution. Changes in the mean, the variance and the distribution of water soluble carbon were followed on 0.4 ha of the 1.2 ha in a grid of sixty points during a crop of wheat and a subsequent crop of sorghum. The mean increased in the spring, decreased in the summer and increased again in the fall. The spring and summer concentrations are well characterized by log normal distributions. The spatial dependence of water soluble carbon was examined on a fifty-five point transect across the field spaced every 1.37 m. The variogram indicated little or no dependence at this spacing. (author)

  10. Enhancing the solubility and bioavailability of poorly water-soluble drugs using supercritical antisolvent (SAS) process.

    Science.gov (United States)

    Abuzar, Sharif Md; Hyun, Sang-Min; Kim, Jun-Hee; Park, Hee Jun; Kim, Min-Soo; Park, Jeong-Sook; Hwang, Sung-Joo

    2018-03-01

    Poor water solubility and poor bioavailability are problems with many pharmaceuticals. Increasing surface area by micronization is an effective strategy to overcome these problems, but conventional techniques often utilize solvents and harsh processing, which restricts their use. Newer, green technologies, such as supercritical fluid (SCF)-assisted particle formation, can produce solvent-free products under relatively mild conditions, offering many advantages over conventional methods. The antisolvent properties of the SCFs used for microparticle and nanoparticle formation have generated great interest in recent years, because the kinetics of the precipitation process and morphologies of the particles can be accurately controlled. The characteristics of the supercritical antisolvent (SAS) technique make it an ideal tool for enhancing the solubility and bioavailability of poorly water-soluble drugs. This review article focuses on SCFs and their properties, as well as the fundamentals of overcoming poorly water-soluble drug properties by micronization, crystal morphology control, and formation of composite solid dispersion nanoparticles with polymers and/or surfactants. This article also presents an overview of the main aspects of the SAS-assisted particle precipitation process, its mechanism, and parameters, as well as our own experiences, recent advances, and trends in development. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Determination of water-soluble forms of oxalic and formic acids in soils by ion chromatography

    Science.gov (United States)

    Karicheva, E.; Guseva, N.; Kambalina, M.

    2016-03-01

    Carboxylic acids (CA) play an important role in the chemical composition origin of soils and migration of elements. The content of these acids and their salts is one of the important characteristics for agrochemical, ecological, ameliorative and hygienic assessment of soils. The aim of the article is to determine water-soluble forms of same carboxylic acids — (oxalic and formic acids) in soils by ion chromatography with gradient elution. For the separation and determination of water-soluble carboxylic acids we used reagent-free gradient elution ion-exchange chromatography ICS-2000 (Dionex, USA), the model solutions of oxalate and formate ions, and leachates from soils of the Kola Peninsula. The optimal gradient program was established for separation and detection of oxalate and formate ions in water solutions by ion chromatography. A stability indicating method was developed for the simultaneous determination of water-soluble organic acids in soils. The method has shown high detection limits such as 0.03 mg/L for oxalate ion and 0.02 mg/L for formate ion. High signal reproducibility was achieved in wide range of intensities which correspond to the following ion concentrations: from 0.04 mg/g to 10 mg/L (formate), from 0.1 mg/g to 25 mg/L (oxalate). The concentration of formate and oxalate ions in soil samples is from 0.04 to 0.9 mg/L and 0.45 to 17 mg/L respectively.

  12. Water uptake by fresh Indonesian peat burning particles is limited by water-soluble organic matter

    Science.gov (United States)

    Chen, Jing; Hapsari Budisulistiorini, Sri; Itoh, Masayuki; Lee, Wen-Chien; Miyakawa, Takuma; Komazaki, Yuichi; Qing Yang, Liu Dong; Kuwata, Mikinori

    2017-09-01

    The relationship between hygroscopic properties and chemical characteristics of Indonesian biomass burning (BB) particles, which are dominantly generated from peatland fires, was investigated using a humidified tandem differential mobility analyzer. In addition to peat, acacia (a popular species at plantation) and fern (a pioneering species after disturbance by fire) were used for experiments. Fresh Indonesian peat burning particles are almost non-hygroscopic (mean hygroscopicity parameter, κ octanol-water partitioning method. κ values for the water extracts are high, especially for peat burning particles (A0 (a whole part of the water-soluble fraction): κ = 0.18, A1 (highly water-soluble fraction): κ = 0.30). This result stresses the importance of both the WSOC fraction and κ of the water-soluble fraction in determining the hygroscopicity of organic aerosol particles. Values of κ correlate positively (R = 0.89) with the fraction of m/z 44 ion signal quantified using a mass spectrometric technique, demonstrating the importance of highly oxygenated organic compounds to the water uptake by Indonesian BB particles. These results provide an experimentally validated reference for hygroscopicity of organics-dominated particles, thus contributing to more accurate estimation of environmental and climatic impacts driven by Indonesian BB particles on both regional and global scales.

  13. Changes in the content of water-soluble vitamins in Actinidia chinensis during cold storage

    Directory of Open Access Journals (Sweden)

    Zhu Xian-Bo

    2016-01-01

    Full Text Available We assessed the effects of cold storage on nine water-soluble vitamins in 7 cultivars of Actinidia chinensis (kiwifruit using high-performance liquid chromatography. Samples were collected at three time points during cold storage: one day, 30 days, and when edible. We found that vitamin C in most cultivars was raised with cold storage, but there was no consistent increased or decreased trend for other water-soluble vitamins across cultivars in storage. After one day of cold storage, vitamins B1 and B2 were the most prevalent vitamins in Control (wild fruit, while vitamins B5 and B6 were most prevalent in the Hongyang and Qihong cultivars. However, B12 was the most prevalent vitamin in the Qihong cultivar after 30 days of cold storage. Vitamins B3, B7, B9, and C were detected at the edible time point in Huayou, Hongyang, Jinnong-2, and Control fruit. Vitamin contents varied significantly among cultivars of kiwifruit following different durations of cold storage. Out of the three durations tested, a period of 30 days in cold storage was the most suitable for the absorption of water-soluble vitamins by A. chinensis.

  14. Transpiration directly regulates the emissions of water-soluble short-chained OVOCs.

    Science.gov (United States)

    Rissanen, K; Hölttä, T; Bäck, J

    2018-04-20

    Most plant-based emissions of volatile organic compounds (VOCs) are considered mainly temperature dependent. However, certain oxygenated VOCs (OVOCs) have high water solubility; thus, also stomatal conductance could regulate their emissions from shoots. Due to their water solubility and sources in stem and roots, it has also been suggested that their emissions could be affected by transport in xylem sap. Yet, further understanding on the role of transport has been lacking until present. We used shoot-scale long-term dynamic flux data from Scots pines (Pinus sylvestris) to analyse the effects of transpiration and transport in xylem sap flow on emissions of three water soluble OVOC: methanol, acetone and acetaldehyde. We found a direct effect of transpiration on the shoot emissions of the three OVOCs. The emissions were best explained by a regression model that combined linear transpiration and exponential temperature effects. In addition, a structural equation model indicated that stomatal conductance affects emissions mainly indirectly, by regulating transpiration. A part of temperature's effect is also indirect. The tight coupling of shoot emissions to transpiration clearly evidences that these OVOCs are transported in xylem sap from their sources in roots and stem to leaves and to ambient air. This article is protected by copyright. All rights reserved.

  15. Synthesis and properties of amino acid functionalized water-soluble perylene diimides

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yongshan; Li, Xuemei; Wei, Xiaofeng; Jiang, Tianyi; Wu, Junsen; Ren, Huixue [Shandong Jianzhu University, Jinan (China)

    2015-07-15

    We prepared amino acid functionalized water-soluble perylene diimides: N,N'-bi(L-glutamic acid)-perylene-3,4;9,10-dicarboxylic diimide (1), N,N'-bi(L-phenylalanine acid)-perylene-3,4;9,10-dicarboxylic diimide (2), N,N'-bi(Lglutamic amine)-perylene-3,4;9,10-dicarboxylic diimide (3) and N,N'-bi(L-phenylalanine amine)-perylene-3,4;9,10-dicarboxylic diimide (4). The structures of 3 and 4 were confirmed by {sup 1}H NMR, FT-IR and MS. The maximal absorption bands of compound 1 and 2 in concentrated sulfuric acid were red-shifted for about 48 and 74 nm, respectively, compared with that of Perylene-3,4,9,10-tetracarboxylic acid dianhydride (PTCDA). Nearly no fluorescence was observed for compounds 1 and 2 in water, while compounds 3 and 4 were significantly water-soluble and had very high fluorescent quantum. The mechanism of the optical properties change was discussed, and the π-π stacking caused by H{sup +} led to the changes of fluorescence spectrum and absorption spectrum. The calculated molecular orbital energies and the frontier molecular orbital maps of compounds 1-2 based on density function theory (DFT) calculations were reported. Owing to the high water-soluble, the perylene derivatives 3 and 4 were successfully applied as high-performance fluorochromes for living hela cells imaging.

  16. Abalone water-soluble matrix for self-healing biomineralization of tooth defects.

    Science.gov (United States)

    Wen, Zhenliang; Chen, Jingdi; Wang, Hailiang; Zhong, Shengnan; Hu, Yimin; Wang, Zhili; Zhang, Qiqing

    2016-10-01

    Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53wt% the abalone water-soluble protein (AWSPro) and 2.04wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Water uptake by fresh Indonesian peat burning particles is limited by water-soluble organic matter

    Directory of Open Access Journals (Sweden)

    J. Chen

    2017-09-01

    Full Text Available The relationship between hygroscopic properties and chemical characteristics of Indonesian biomass burning (BB particles, which are dominantly generated from peatland fires, was investigated using a humidified tandem differential mobility analyzer. In addition to peat, acacia (a popular species at plantation and fern (a pioneering species after disturbance by fire were used for experiments. Fresh Indonesian peat burning particles are almost non-hygroscopic (mean hygroscopicity parameter, κ < 0.06 due to predominant contribution of water-insoluble organics. The range of κ spans from 0.02 to 0.04 (dry diameter = 100 nm, hereinafter for Riau peat burning particles, while that for Central Kalimantan ranges from 0.05 to 0.06. Fern combustion particles are more hygroscopic (κ = 0. 08, whereas the acacia burning particles have a mediate κ value (0.04. These results suggest that κ is significantly dependent on biomass types. This variance in κ is partially determined by fractions of water-soluble organic carbon (WSOC, as demonstrated by a correlation analysis (R = 0.65. κ of water-soluble organic matter is also quantified, incorporating the 1-octanol–water partitioning method. κ values for the water extracts are high, especially for peat burning particles (A0 (a whole part of the water-soluble fraction: κ = 0.18, A1 (highly water-soluble fraction: κ = 0.30. This result stresses the importance of both the WSOC fraction and κ of the water-soluble fraction in determining the hygroscopicity of organic aerosol particles. Values of κ correlate positively (R = 0.89 with the fraction of m∕z 44 ion signal quantified using a mass spectrometric technique, demonstrating the importance of highly oxygenated organic compounds to the water uptake by Indonesian BB particles. These results provide an experimentally validated reference for hygroscopicity of organics-dominated particles, thus contributing to more accurate

  18. Study to evaluate the impact of heat treatment on water soluble vitamins in milk.

    Science.gov (United States)

    Asadullah; Khair-un-nisa; Tarar, Omer Mukhtar; Ali, Syed Abdul; Jamil, Khalid; Begum, Askari

    2010-11-01

    To evaluate the effect of domestic boiling practice on the contents of water soluble vitamins of loose milk and quantitative comparison of these vitamins in Ultra High Temperature (UHT) treated packaged milk with that of boiled loose milk. Loose milk samples were collected from various localities of Karachi city (Pakistan). These samples were boiled in simulated household conditions for 5, 10 and 15 minutes. Ultra High Temperature (UHT) treated packaged milk samples of various brands were obtained from the local market. The aliquots were analyzed for water-soluble vitamins using High Performance Liquid Chromatography (HPLC) technique. The mean values and standard deviations for data were computed and compared as well as level of variations were also determined. Conventional boiling caused destruction of water soluble vitamins in milk i.e. vitamin 81 content in fresh milk decreased from 0.037 mg/100 g to 0.027 mg/100 g after 15 min boiling, whereas vitamin B2 from 0.115 to 0.084 mg/100 g, vitamin B3 0.062 to 0.044 mg/100 g, vitamin B6 0.025 to 0.019 mg/100 g and folic acid 3.38 to 2.40 microg/100 g. This accounted for a post-boiling decrease of about 27, 27, 29, 24 and 36% in vitamins B1, B2, B3, B6 and folic acid respectively. The values for vitamins B1, B2, B3, B6 and folic acid determined in boiled milk were significantly lower than UHT treated packaged milk samples by 25.9, 75.0, 54.5, 63.16 and 38.1% respectively. Conventional boiling caused drastic reduction in vitamin levels of loose milk samples. In comparison to this, UHT milk retained high levels of water soluble B-vitamins. Thus it could be envisaged that UHT treated milk provides better water soluble vitamins' nourishment than conventionally boiled milk (JPMA 60:909; 2010).

  19. Study to evaluate the impact of heat treatment on water soluble vitamins in milk

    International Nuclear Information System (INIS)

    Khair-un-Nisa, A.; Tarar, O.M.; Ali, S.A.; Jamil, K.; Begum, A.

    2010-01-01

    Objectives: To evaluate the effect of domestic boiling practice on the contents of water soluble vitamins of loose milk and quantitative comparison of these vitamins in Ultra High Temperature (UHT) treated packaged milk with that of boiled loose milk. Methods: Loose milk samples were collected from various localities of Karachi city (Pakistan). These samples were boiled in simulated household conditions for 5, 10 and 15 minutes. Ultra High Temperature (UHT) treated packaged milk samples of various brands were obtained from the local market. The aliquots were analyzed for water-soluble vitamins using High Performance Liquid Chromatography (HPLC) technique. The mean values and standard deviations for data were computed and compared as well as level of variations were also determined. Results: Conventional boiling caused destruction of water soluble vitamins in milk i.e. vitamin B1 content in fresh milk decreased from 0.037 mg/100g to 0.027 mg/100g after 15 min boiling, whereas vitamin B2 from 0.115 to 0.084 mg/100g, vitamin B3 0.062 to 0.044 mg/100g, vitamin B6 0.025 to 0.019 mg/100g and folic acid 3.38 to 2.40 < g/100g. This accounted for a post-boiling decrease of about 27, 27, 29, 24 and 36% in vitamins B1, B2, B3, B6 and folic acid respectively. The values for vitamins B1, B2, B3, B6 and folic acid determined in boiled milk were significantly lower than UHT treated packaged milk samples by 25.9, 75.0, 54.5, 63.16 and 38.1% respectively. Conclusion: Conventional boiling caused drastic reduction in vitamin levels of loose milk samples. In comparison to this, UHT milk retained high levels of water soluble B-vitamins. Thus it could be envisaged that UHT treated milk provides better water soluble vitamins' nourishment than conventionally boiled milk. (author)

  20. On the characterization of dynamic supramolecular systems: a general mathematical association model for linear supramolecular copolymers and application on a complex two-component hydrogen-bonding system.

    Science.gov (United States)

    Odille, Fabrice G J; Jónsson, Stefán; Stjernqvist, Susann; Rydén, Tobias; Wärnmark, Kenneth

    2007-01-01

    A general mathematical model for the characterization of the dynamic (kinetically labile) association of supramolecular assemblies in solution is presented. It is an extension of the equal K (EK) model by the stringent use of linear algebra to allow for the simultaneous presence of an unlimited number of different units in the resulting assemblies. It allows for the analysis of highly complex dynamic equilibrium systems in solution, including both supramolecular homo- and copolymers without the recourse to extensive approximations, in a field in which other analytical methods are difficult. The derived mathematical methodology makes it possible to analyze dynamic systems such as supramolecular copolymers regarding for instance the degree of polymerization, the distribution of a given monomer in different copolymers as well as its position in an aggregate. It is to date the only general means to characterize weak supramolecular systems. The model was fitted to NMR dilution titration data by using the program Matlab, and a detailed algorithm for the optimization of the different parameters has been developed. The methodology is applied to a case study, a hydrogen-bonded supramolecular system, salen 4+porphyrin 5. The system is formally a two-component system but in reality a three-component system. This results in a complex dynamic system in which all monomers are associated to each other by hydrogen bonding with different association constants, resulting in homo- and copolymers 4n5m as well as cyclic structures 6 and 7, in addition to free 4 and 5. The system was analyzed by extensive NMR dilution titrations at variable temperatures. All chemical shifts observed at different temperatures were used in the fitting to obtain the DeltaH degrees and DeltaS degrees values producing the best global fit. From the derived general mathematical expressions, system 4+5 could be characterized with respect to above-mentioned parameters.

  1. Effect of Bombay high crude oil and its water-soluble fraction on growth and metabolism of diatom Thalassiosira sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Parab, S.R.; Pandit, R.A.; Kadam, A.N.; Indap, M.M.

    Effect of Bombay high crude oil (BHC) and its water-soluble fraction (WSF) on growth and metabolism of the phytoplankton, Thalassiosira sp. was assessed. The study revealed the signs of acute toxicity at higher concentrations of crude oil (0...

  2. Simultaneous quantification of 21 water soluble vitamin circulating forms in human plasma by liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Meisser Redeuil, Karine; Longet, Karin; Bénet, Sylvie; Munari, Caroline; Campos-Giménez, Esther

    2015-11-27

    This manuscript reports a validated analytical approach for the quantification of 21 water soluble vitamins and their main circulating forms in human plasma. Isotope dilution-based sample preparation consisted of protein precipitation using acidic methanol enriched with stable isotope labelled internal standards. Separation was achieved by reversed-phase liquid chromatography and detection performed by tandem mass spectrometry in positive electrospray ionization mode. Instrumental lower limits of detection and quantification reached water soluble vitamins in human plasma single donor samples. The present report provides a sensitive and reliable approach for the quantification of water soluble vitamins and main circulating forms in human plasma. In the future, the application of this analytical approach will give more confidence to provide a comprehensive assessment of water soluble vitamins nutritional status and bioavailability studies in humans. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Water-Soluble N-Heterocyclic Carbene-Protected Gold Nanoparticles: Size-Controlled Synthesis, Stability, and Optical Properties

    OpenAIRE

    Salorinne, Kirsi; Man, Renee W.Y.; Li, Chien-Hung; Taki, Masayasu; Nambo, Masakazu; Crudden, Cathleen M.

    2017-01-01

    NHC-Au(I) complexes were used to prepare stable, water-soluble, NHC-protected gold nanoparticles. The water-soluble, charged nature of the nanoparticles permitted analysis by polyacrylamide gel electrophoresis (PAGE), which showed that the nanoparticles were highly monodisperse, with tunable core diameters between 2.0 and 3.3 nm depending on the synthesis conditions. Temporal, thermal, and chemical stability of the nanoparticles were determined to be high. Treatment with thiols caused etching...

  4. Preparations and properties of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials.

    Science.gov (United States)

    Watanabe, Shoji

    2008-01-01

    This short review describes various types of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials. It is concerned with synthetic additives classified according to their functional groups; silicone compounds, carboxylic acids and dibasic acids, esters, Diels-Alder adducts, various polymers, nitrogen compounds, phosphoric esters, phosphonic acids, and others. Testing methods for water-soluble metal working fluids for aluminum alloy materials are described for a practical application in a laboratory.

  5. Follow-up barium study after a negative water-soluble contrast examination for suspected esophageal leak: is it necessary?

    Science.gov (United States)

    Sanchez, Thomas R; Holz, Grant S; Corwin, Michael T; Wood, Robert J; Wootton-Gorges, Sandra L

    2015-10-01

    The purpose of this study was to determine the value of follow-up barium esophogram in diagnosing esophageal injury or leak if the initial water-soluble contrast examination of the esophagus is normal. An institutional review board (IRB)-approved retrospective review of all pediatric patients less than 18 years old referred to the radiology department for evaluation of esophageal injury or leak was performed for a 9-year period from 2005 to 2014. The majority of patients had unexplained pneumomediastinum, chest trauma (gunshot or puncture wound), or foreign body ingestion as the reason for the referral. Forty-nine patients (age range 10 days to 17 years) underwent an initial water-soluble esophogram immediately followed by a barium esophogram. Forty-six studies were negative on both water-soluble contrast and barium studies. Two studies were both positive on the initial water-soluble contrast and subsequent barium studies. A single study showed the esophageal leak only in the water-soluble study, with the follow-up barium exam being normal. The result of this study indicates that a single-contrast water-soluble esophogram alone is sensitive in the diagnosis of esophageal injury or leak. It has a 100 % sensitivity and negative predictive value. A follow-up barium esophogram only increases the study time and radiation dose to the patient.

  6. Urinary water-soluble vitamins and their metabolite contents as nutritional markers for evaluating vitamin intakes in young Japanese women.

    Science.gov (United States)

    Fukuwatari, Tsutomu; Shibata, Katsumi

    2008-06-01

    Little information is available to estimate water-soluble vitamin intakes from urinary vitamins and their metabolite contents as possible nutritional markers. Determination of the relationships between the oral dose and urinary excretion of water-soluble vitamins in human subjects contributes to finding valid nutrition markers of water-soluble vitamin intakes. Six female Japanese college students were given a standard Japanese diet in the first week, the same diet with a synthesized water-soluble vitamin mixture as a diet with approximately onefold vitamin mixture based on Dietary Reference Intakes (DRIs) for Japanese in the second week, with a threefold vitamin mixture in the third week, and a sixfold mixture in the fourth week. Water-soluble vitamins and their metabolites were measured in the 24-h urine collected each week. All urinary vitamins and their metabolite levels except vitamin B(12) increased linearly in a dose-dependent manner, and highly correlated with vitamin intake (r=0.959 for vitamin B(1), r=0.927 for vitamin B(2), r=0.965 for vitamin B(6), r=0.957 for niacin, r=0.934 for pantothenic acid, r=0.907 for folic acid, r=0.962 for biotin, and r=0.952 for vitamin C). These results suggest that measuring urinary water-soluble vitamins and their metabolite levels can be used as good nutritional markers for assessing vitamin intakes.

  7. Improved Bilayer Resist System Using Contrast-Enhanced Lithography With Water-Soluble Photopolymer

    Science.gov (United States)

    Sasago, Masaru; Endo, Masayuki; Hirai, Yoshihiko; Ogawa, Kazufurni; Ishihara, Takeshi

    1986-07-01

    A new water-soluble contract enhanced material, WSP (Water-soluble Photopolymer), has been developed. The WSP is composed of a mainpolymer and a photobleachable reagents. The mainpolymer is a water-soluble polymer mixed with pullulan (refined through biotechnological process) and polyvinyl-pyrolidone (PVP). The photo-bleachable reagent is of a diazonium compound gorup. The introduction of the mainpolymer and photobleach-able reagent mixture has improved filmity, gas transparency, photobleaching characteristics and solubility in alkaline which are essential to the device fabrication. Submicron photoresist patterns are successfully fabricated by a simple sequence of photolithography process. The WSP layer has been applied to the bilayer resist system--deep-UV portable conformable masking (PCM)--that is not affected by VLSI's topography, and is able to fabricate highly accurate pattern. The aqueous developable layer, PMGI, with high organic solvent resistance is used in the bottom layer. Therefore, no interfacial mixing with conventional positive resist top layer is observed. Furthermore, deep-UV exposure method has been used for the KrF excimer laser optical system in order to increase high throughput. From the experiments, it has been confirmed that good resist transfer profile can be realized by the use of WSP, and that the submicron resist patterns with high aspect-ratio can be developed on the nonplaner wafer with steps of up to 41m by the combination of the WSP with the PCM system. By this technology, has been improved the weak point: variation in the line width due to the thickness of contrast-enhanced layer when the CEL technology is applied, and dependency of both the finished resist profile and the line-width accuracy on the thickness of the top layer resist when the PCM system is adopted.

  8. N-succinyl-chitosan as a drug carrier: water-insoluble and water-soluble conjugates.

    Science.gov (United States)

    Kato, Yoshinori; Onishi, Hiraku; Machida, Yoshiharu

    2004-02-01

    N-succinyl-chitosan (Suc-Chi) has favourable properties as a drug carrier such as biocompatibility, low toxicity and long-term retention in the body. It was long retained in the systemic circulation after intravenous administration, and the plasma half-lives of Suc-Chi (MW: 3.4 x 10(5); succinylation degree: 0.81 mol/sugar unit; deacetylation degree: 1.0 mol/sugar unit) were ca. 100.3h in normal mice and 43 h in Sarcoma 180-bearing mice. The biodistribution of Suc-Chi into other tissues was trace apart from the prostate and lymph nodes. The maximum tolerable dose for the intraperitoneal injection of Suc-Chi to mice was greater than 2 g/kg. The water-insoluble and water-soluble conjugates could be prepared using a water-soluble carbodiimide and mitomycin C (MMC) or using an activated ester of glutaric MMC. In vitro release characteristics of these conjugates showed similar patterns, i.e. a pH-dependent manner, except that water-insoluble conjugates showed a slightly slower release of MMC than water-soluble ones. The conjugates of MMC with Suc-Chi showed good antitumour activities against various tumours such as murine leukaemias (L1210 and P388), B16 melanoma, Sarcoma 180 solid tumour, a murine liver metastatic tumour (M5076) and a murine hepatic cell carcinoma (MH134). This review summarizes the utilization of Suc-Chi as a drug carrier for macromolecular conjugates of MMC and the therapeutic efficacy of the conjugates against various tumours.

  9. Geochemical evidence of water-soluble gas accumulation in the Weiyuan gas field, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Shengfei Qin

    2016-01-01

    Full Text Available At present, there are several different opinions on the formation process of the Weiyuan gas field in the Sichuan Basin and the source of its natural gas. In view of the fact that the methane carbon isotope of the natural gas in the Weiyuan gas field is abnormally heavy, the geologic characteristics of gas reservoirs and the geochemical characteristics of natural gas were first analyzed. In the Weiyuan gas field, the principal gas reservoirs belong to Sinian Dengying Fm. The natural gas is mainly composed of methane, with slight ethane and trace propane. The gas reservoirs are higher in water saturation, with well preserved primary water. Then, it was discriminated from the relationship of H2S content vs. methane carbon isotope that the heavier methane carbon isotope of natural gas in this area is not caused by thermochemical sulfate reduction (TSR. Based on the comparison of methane carbon isotope in this area with that in adjacent areas, and combined with the tectonic evolution background, it is regarded that the natural gas in the Weiyuan gas field is mainly derived from water-soluble gas rather than be migrated laterally from adjacent areas. Some conclusions are made. First, since methane released from water is carbon isotopically heavier, the water-soluble gas accumulation after degasification results in the heavy methane carbon isotope of the gas produced from Weiyuan gas field. Second, along with Himalayan movement, great uplift occurred in the Weiyuan area and structural traps were formed. Under high temperature and high pressure, the gas dissolved in water experienced decompression precipitation, and the released natural gas accumulated in traps, consequently leading to the formation of Weiyuan gas field. Third, based on calculation, the amount of natural gas released from water which is entrapped in the Weiyuan gas field after the tectonic uplift is basically equal to the proved reserves of this field, confirming the opinion of water-soluble

  10. Water-soluble triazabutadienes that release diazonium species upon protonation under physiologically relevant conditions.

    Science.gov (United States)

    Kimani, Flora W; Jewett, John C

    2015-03-23

    Triazabutadienes are an understudied structural motif that have remarkable reactivity once rendered water-soluble. It is shown that these molecules readily release diazonium species in a pH-dependent manner in a series of buffer solutions with pH ranges similar to those found in cells. Upon further development, we expect that this process will be well suited to cargo-release strategies and organelle-specific bioconjugation reactions. These compounds offer one of the mildest ways of generating diazonium species in aqueous solutions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Preparation and tribology properties of water-soluble fullerene derivative nanoball

    Directory of Open Access Journals (Sweden)

    Guichang Jiang

    2017-02-01

    Full Text Available Water-soluble fullerene derivatives were synthesized via radical polymerization. They are completely soluble in water, yielding a clear brown solution. The products were characterized by FTIR, UV–Vis, 1H-NMR, 13CNMR, GPC, TGA, and SEM. Four-ball tests show that the addition of a certain concentration of the fullerene derivatives to base stock (2 wt.% triethanolamine aqueous solution can effectively increase both the load-carrying capacity (PB value, and the resistance to wear. SEM observations confirm the additive results in a reduced diameter of the wear scar and decreased wear.

  12. Graft copolymerization of water soluble mixed monomers onto polyethylene by the pre-irradiation method

    International Nuclear Information System (INIS)

    Long Fu; Tang Liming; Zhao Jin; Gao Zhenyong

    1993-01-01

    Grafting of water soluble mixed monomers of acrylic acid (AA)/acrylamide (Am) and acrylic acid/methacrylic acid (MA) onto polyethylene film by the pre-irradiation grafting method was investigated. The results showed that the grafting proceeded successfully with the adding of ferric salt in the solution. In the case of AA/Am system, a synergistic effect was noticed. In the case of AA/MA system, the graft percent increased with the increase in the concentration of MA in the feed ratio. Furthermore, the effects of monomer concentration, radiation dose and temperature on the grafting were also studied

  13. Encapsulation of Polythiophene by Glycopolymer for Water Soluble Nano-wire

    Energy Technology Data Exchange (ETDEWEB)

    T Fukuda; Y Inoue; T Koga; M Matsuoka; Y Miura

    2011-12-31

    A water-soluble polythiophene (PT) was prepared by the self-assembling complex with a glycopolymer. The glycopolymer of poly(N-p-vinylbenzyl-D-lactonamide) (PVLA) formed self-assembling cylindrical structure based on the amphiphilicity even after the complexation with PT. We confirmed the improved optical functionality of PT due to the longer conjugated {pi}-orbital. It suggested that PT behaved like molecular nanowire with the self-assembled structure in the hydrophobic core of PVLA. PVLA-PT also showed specific biorecognition against corresponding lectin. These results suggested that the bioactive nanowire formation of PT with the glycopolymer was developed.

  14. Capacity for absorption of water-soluble secondary metabolites greater in birds than in rodents.

    Science.gov (United States)

    Karasov, William H; Caviedes-Vidal, Enrique; Bakken, Bradley Hartman; Izhaki, Ido; Samuni-Blank, Michal; Arad, Zeev

    2012-01-01

    Plant secondary metabolites (SMs) are pervasive in animal foods and potentially influence feeding behavior, interspecies interactions, and the distribution and abundance of animals. Some of the major classes of naturally occurring SMs in plants include many water-soluble compounds in the molecular size range that could cross the intestinal epithelium via the paracellular space by diffusion or solvent drag. There are differences among species in paracellular permeability. Using Middle Eastern rodent and avian consumers of fruits containing SMs, we tested the hypothesis that avian species would have significantly higher paracellular permeability than rodent species. Permeability in intact animals was assessed using standard pharmacological methodology to measure absorption of two radiolabeled, inert, neutral water-soluble probes that do not interact with intestinal nutrient transporters, L-arabinose (M(r) = 150.1 Da) and lactulose (M(r) = 342.3 Da). We also measured absorption of labeled 3-O-methyl-D-glucose (3OMD-glucose; M(r) = 194.2 Da), which is a nonmetabolized analogue of D-glucose that is passively absorbed through the paracellular space but also transported across the enterocyte membranes. Most glucose was absorbed by all species, but arabinose fractional absorption (f) was nearly three times higher in birds (1.03±0.17, n = 15 in two species) compared to rodents (0.37±0.06, n = 10 in two species) (Pbirds of arabinose exceeded those of 3OMD-glucose. Our findings are in agreement with previous work showing that the paracellular pathway is more prominent in birds relative to nonflying mammals, and suggests that birds may be challenged by greater absorption of water-soluble, dietary SMs. The increased expression of the paracellular pathway in birds hints at a tradeoff: the free energy birds gain by absorbing water-soluble nutrients passively may be offset by the metabolic demands placed on them to eliminate concomitantly absorbed SMs.

  15. Sensory and chromatographic evaluations of water soluble fractions from air-dried sausages

    DEFF Research Database (Denmark)

    Henriksen, Anders Peter; Stahnke, Marie Louise Heller

    1997-01-01

    Low molecular weight water soluble compounds were extracted from Danish salami, Italian sausage, and Spanish Chorizo. The extracts were fractionated by gel filtration chromatography revealing peptides with a molecular weight less than 4200 Dalton. Fractions consisting of smaller peptides and free...... amino acids had enhanced savory taste impressions described as mainly bouillon, bitter, sour, salty and plastic with odor notes of boiled potato. Determination of amino acids in the fractions before and after hydrolysis revealed the presence of mainly hydrophilic peptides in all fractions. Partial least...

  16. The synthesis of a water-soluble derivative of rutin as an antiradical agent

    Energy Technology Data Exchange (ETDEWEB)

    Pedriali, Carla Aparecida; Fernandes, Adjaci Uchoa [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Quimica. Dept. de Bioquimica]. E-mail: capedriali@hotmail.com; Bernusso, Leandra de Cassia; Polakiewicz, Bronislaw [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Tecnologia Bioquimico-Farmaceutica

    2008-07-01

    The purpose of this study was to synthesize a water-soluble derivative of rutin (compound 2) by introducing carboxylate groups on rutin's sugar moiety. The rutin derivative showed an almost 100-fold solubility increase in water. The antiradical capacity of compound 2 was evaluated using the luminol/AAPH system, and the derivative's activity was 1.5 times greater than that of Trolox. Despite the derivative's high solubility in water (log P = -1.13), lipid peroxidation of brain homogenate membranes was very efficiently inhibited (inhibition values were only 19% lower than the inhibition values of rutin). (author)

  17. Effect of water soluble carrier on dissolution profiles of diclofenac sodium.

    Science.gov (United States)

    Cwiertnia, Barbara

    2013-01-01

    Pharmaceutical aviailability of diclofenac sodium from solid dispersions of PEG 6000 have been studied in comparison to those of the corresponding physical mixtures and pure diclofenac sodium. The diclofenac sodium is poorly water soluble drug. The properties of diclofenac sodium-PEG 6000 solid dispersions have been determined by the methods of differential scanning calorimetry (DSC), X-ray diffraction and scanning electron microscopy (SEM). The effect of PEG 6000 on the solubility of selected diclofenac sodium dispersions has been studied. The solubility of diclofenac sodium from its solid dispersion has been found to increase in the presence of PEG 6000.

  18. Efficient Route to Highly Water-Soluble Aromatic Cyclic Hydroxamic Acid Ligands

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, Michael; Raymond, Kenneth N.

    2008-02-06

    2-Hydroxyisoquinolin-1-one (1,2-HOIQO) is a new member of the important class of aromatic cyclic hydroxamic acid ligands which are widely used in metal sequestering applications and metal chelating therapy. The first general approach for the introduction of substituents at the aromatic ring of the chelating moiety is presented. As a useful derivative, the highly water-soluble sulfonic acid has been synthesized by an efficient route that allows general access to 1,2-HOQIO 3-carboxlic acid amides, which are the most relevant for applications.

  19. Synthesis and characterization of a fluorescent water-soluble paclitaxel prodrug.

    Science.gov (United States)

    Sohn, Jeong-Sun; Choi, Eun-Sun; Jo, Byung-Wook; Hess, Michael; Han, Song-Hee

    2010-05-01

    A fluorescence susceptible water-soluble paclitaxel was synthesized by a condensation reaction between PEGylated paclitaxel (namely, PP7) and 1-pyrene butyric acid (PBA) in order to obtain a better understanding of the mechanism of action of paclitaxel as well as of the environment of the paclitaxel-binding site. The reaction was performed successfully and the resulting paclitaxel was characterized by FT-NMR, analytical-HPLC, UV spectro photometry, and fluorescence spectrometry. The synthesized paclitaxel analogue showed a high susceptibility to fluorescence in both excitation and emission spectra. And we have investigated the time-resolved fluorescence behavior of them in different solvents and at different excitation wavelengths.

  20. [Nutrition and bone health. The bone and the foods containing many water-soluble vitamins].

    Science.gov (United States)

    Ishida, Hiromi

    2009-08-01

    On the Dietary Reference Intakes in Japan, nine kinds of water-soluble vitamins are taken up. Those vitamins are supplied from various food. Food from animal sources and vegetable sources are those vitamins source of supply. Vitamin C participates in generation of collagen. Vitamin C is supplied from vegetables or fruits. Since vitamin C is lost by cooking processing, the content of a raw state is not expectable after cooking. Moreover, the vitamin B group of food origin has combined with protein etc., and free types, such as supplement, differ in the bioavailability.

  1. The synthesis of a water-soluble derivative of rutin as an antiradical agent

    International Nuclear Information System (INIS)

    Pedriali, Carla Aparecida; Fernandes, Adjaci Uchoa; Bernusso, Leandra de Cassia; Polakiewicz, Bronislaw

    2008-01-01

    The purpose of this study was to synthesize a water-soluble derivative of rutin (compound 2) by introducing carboxylate groups on rutin's sugar moiety. The rutin derivative showed an almost 100-fold solubility increase in water. The antiradical capacity of compound 2 was evaluated using the luminol/AAPH system, and the derivative's activity was 1.5 times greater than that of Trolox. Despite the derivative's high solubility in water (log P = -1.13), lipid peroxidation of brain homogenate membranes was very efficiently inhibited (inhibition values were only 19% lower than the inhibition values of rutin). (author)

  2. Sunlight-Induced Photochemical Degradation of Methylene Blue by Water-Soluble Carbon Nanorods

    Directory of Open Access Journals (Sweden)

    Anshu Bhati

    2016-01-01

    Full Text Available Water-soluble graphitic hollow carbon nanorods (wsCNRs are exploited for their light-driven photochemical activities under outdoor sunlight. wsCNRs were synthesized by a simple pyrolysis method from castor seed oil, without using any metal catalyst or template. wsCNRs exhibited the light-induced photochemical degradation of methylene blue used as a model pollutant by the generation of singlet oxygen species. Herein, we described a possible degradation mechanism of methylene blue under the irradiation of visible photons via the singlet oxygen-superoxide anion pathway.

  3. In vitro and in vivo antioxidant activity of a water-soluble polysaccharide from dendrobium denneanum

    Science.gov (United States)

    Luo, A.; Ge, Z.; Fan, Y.; Chun, Z.; Jin, He X.

    2011-01-01

    The water-soluble crude polysaccharide (DDP) obtained from the aqueous extracts of the stem of Dendrobium denneanum through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 484.7 kDa. Monosaccharide analysis revealed that DDP was composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.66:8.92:34.20:10.16. The investigation of antioxidant activity both in vitro and in vivo showed that DDP is a potential antioxidant. ?? 2011.

  4. In Vitro and In Vivo Antioxidant Activity of a Water-Soluble Polysaccharide from Dendrobium denneanum

    Directory of Open Access Journals (Sweden)

    XingJin He

    2011-02-01

    Full Text Available The water-soluble crude polysaccharide (DDP obtained from the aqueous extracts of the stem of Dendrobium denneanum through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw of about  484.7 kDa. Monosaccharide analysis revealed that DDP was composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.66:8.92:34.20:10.16. The investigation of antioxidant activity both in vitro and in vivo showed that DDP is a potential antioxidant.

  5. Synthesis and electrochemical probing of water-soluble poly(sodium 4-styrenesulfonate-co-acrylic acid)-grafted multiwalled carbon nanotubes

    International Nuclear Information System (INIS)

    Du Feipeng; Yang Yingkui; Xie Xiaolin; Wu Kangbing; Gan Tian; Liu Lang

    2008-01-01

    Water-soluble poly(sodium 4-styrenesulfonate-co-acrylic acid)-grafted multiwalled carbon nanotubes (MWNT-g-P(SSS-co-AA)) with core-shell nanostructure were successfully synthesized by in situ free radical copolymerization of sodium 4-strenesulfonate (SSS) and acrylic acid (AA) in the presence of MWNTs terminated with vinyl groups; their structure was characterized by FTIR, 1 H NMR, Raman, TGA and TEM. The results showed that the thickness and content of the copolymer layer grafted onto the MWNT surface are about 7-12 nm and 82.3%, respectively. The P(SSS-co-AA) covalently grafted on MWNTs provides MWNT-g-P(SSS-co-AA) with good hydrophilicity and solubility in water. Then a novel MWNT-g-P(SSS-co-AA)-modified glassy carbon electrode was fabricated by coating; its electrochemical properties were evaluated by electrochemical probe of K 3 [Fe(CN) 6 ], and its catalytic behaviors to the electrochemical oxidation processes of dopamine (DA) and serotonin (5-HT) were investigated. Since the MWNT-g-P(SSS-co-AA)-modified electrode possesses strong electron transfer capability, high electrochemical activity and catalytic ability, it can be used in sensitive, selective, rapid and simultaneous monitoring of biomolecules

  6. Structural and chemical aspects of HPMA copolymers as drug carriers.

    Science.gov (United States)

    Ulbrich, Karel; Subr, Vladimír

    2010-02-17

    Synthetic strategies and chemical and structural aspects of the synthesis of HPMA copolymer conjugates with various drugs and other biologically active molecules are described and discussed in this chapter. The discussion is held from the viewpoint of design and structure of the polymer backbone and biodegradable spacer between a polymer and drug, structure and methods of attachment of the employed drugs to the carrier and structure and methods of conjugation with targeting moieties. Physicochemical properties of the water-soluble polymer-drug conjugates and polymer micelles including mechanisms of drug release are also discussed. Detailed description of biological behavior of the polymer-drug conjugates as well as application of the copolymers for surface modification and targeting of gene delivery vectors are not included, they are presented and discussed in separate chapters of this issue. Copyright 2009 Elsevier B.V. All rights reserved.

  7. Studies on dissolution enhancement and mathematical modeling of drug release of a poorly water-soluble drug using water-soluble carriers.

    Science.gov (United States)

    Ahuja, Naveen; Katare, Om Prakash; Singh, Bhupinder

    2007-01-01

    Role of various water-soluble carriers was studied for dissolution enhancement of a poorly soluble model drug, rofecoxib, using solid dispersion approach. Diverse carriers viz. polyethylene glycols (PEG 4000 and 6000), polyglycolized fatty acid ester (Gelucire 44/14), polyvinylpyrollidone K25 (PVP), poloxamers (Lutrol F127 and F68), polyols (mannitol, sorbitol), organic acid (citric acid) and hydrotropes (urea, nicotinamide) were investigated for the purpose. Phase-solubility studies revealed AL type of curves for each carrier, indicating linear increase in drug solubility with carrier concentration. The sign and magnitude of the thermodynamic parameter, Gibbs free energy of transfer, indicated spontaneity of solubilization process. All the solid dispersions showed dissolution improvement vis-à-vis pure drug to varying degrees, with citric acid, PVP and poloxamers as the most promising carriers. Mathematical modeling of in vitro dissolution data indicated the best fitting with Korsemeyer-Peppas model and the drug release kinetics primarily as Fickian diffusion. Solid state characterization of the drug-poloxamer binary system using XRD, FTIR, DSC and SEM techniques revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement in dissolution rate.

  8. Size distributions of hydrophilic and hydrophobic fractions of water-soluble organic carbon in an urban atmosphere in Hong Kong

    Science.gov (United States)

    Wang, Nijing; Yu, Jian Zhen

    2017-10-01

    Water-soluble organic carbon (WSOC) is a significant part of ambient aerosol and plays an active role in contributing to aerosol's effect on visibility degradation and radiation budget through its interactions with atmospheric water. Size-segregated aerosol samples in the range of 0.056-18 μm were collected using a ten-stage impactor sampler at an urban site in Hong Kong over one-year period. The WSOC samples were separated into hydrophilic (termed WSOC_h) and hydrophobic fractions (i.e., the humic-like substances (HULIS) fraction) through solid-phase extraction procedure. Carbon in HULIS accounted for 40 ± 14% of WSOC. The size distribution of HULIS was consistently characterized in all seasons with a dominant droplet mode (46-71%) and minor condensation (9.0-18%) and coarse modes (20-35%). The droplet mode had a mass median aerodynamic diameter in the range of 0.7-0.8 μm. This size mode showed the largest seasonal variation in abundance, lowest in the summer (0.41 μg/m3) and highest in the winter (3.3 μg/m3). WSOC_h also had a dominant droplet mode, but was more evenly distributed among different size modes. Inter-species correlations within the same size mode suggest that the condensation-mode HULIS was partly associated with combustion sources and the droplet-mode was strongly associated with secondary sulfate formation and biomass burning particle aging processes. There is evidence to suggest that the coarse-mode HULIS largely originated from coagulation of condensation-mode HULIS with coarse soil/sea salt particles. The formation process and possible sources of WSOC_h was more complicated and multiple than HULIS and need further investigation. Our measurements indicate that WSOC components contributed a dominant fraction of water-soluble aerosol mass in particles smaller than 0.32 μm while roughly 20-30% in the larger particles.

  9. Water-soluble derivatives of 25-OCH3-PPD and their anti-proliferative activities.

    Science.gov (United States)

    Zhou, Wu-Xi; Sun, Yuan-Yuan; Yuan, Wei-Hui; Zhao, Yu-Qing

    2017-05-01

    (20R)-25-Methoxyl-dammarane-3β,12β,20-triol (25-OCH 3 -PPD, AD-1) is a dammarane-type sapogenin showing anti-tumor potential. In the search for new anti-tumor agents with higher potency than our previously identified compound 25-OCH 3 -PPD, 11 novel sulfamic acid and diacid derivatives that could improve water solubility and contribute to good drug potency and pharmacokinetic profiles were designed and synthesized. Their in vitro anti-tumor activities in MCF-7, A-549, HCT-116, and BGC-823 cell lines and one normal cell line were tested by standard MTT assay. Results showed that compared with compound 25-OCH 3 -PPD, compounds 1, 4, and 5 exhibited higher cytotoxic activity on almost all cell lines, together with lower toxicity in the normal cell. In particular, compound 1 exhibited the best anti-tumor activity in the in vitro assays. The water solubility of 25-OCH 3 -PPD and its derivatives was tested and the results showed that the solubility of 25-OCH 3 -PPD sulfamic acid and diacid derivatives were better than that of 25-OCH 3 -PPD in water, which may provide valuable data for the research and development of new anti-tumor agents. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Novel electrosprayed nanospherules for enhanced aqueous solubility and oral bioavailability of poorly water-soluble fenofibrate.

    Science.gov (United States)

    Yousaf, Abid Mehmood; Mustapha, Omer; Kim, Dong Wuk; Kim, Dong Shik; Kim, Kyeong Soo; Jin, Sung Giu; Yong, Chul Soon; Youn, Yu Seok; Oh, Yu-Kyoung; Kim, Jong Oh; Choi, Han-Gon

    2016-01-01

    The purpose of the present research was to develop a novel electrosprayed nanospherule providing the most optimized aqueous solubility and oral bioavailability for poorly water-soluble fenofibrate. Numerous fenofibrate-loaded electrosprayed nanospherules were prepared with polyvinylpyrrolidone (PVP) and Labrafil(®) M 2125 as carriers using the electrospray technique, and the effect of the carriers on drug solubility and solvation was assessed. The solid state characterization of an optimized formulation was conducted by scanning electron microscopy, powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopic analyses. Oral bioavailability in rats was also evaluated for the formulation of an optimized nanospherule in comparison with free drug and a conventional fenofibrate-loaded solid dispersion. All of the electrosprayed nanospherule formulations had remarkably enhanced aqueous solubility and dissolution compared with free drug. Moreover, Labrafil M 2125, a surfactant, had a positive influence on the solubility and dissolution of the drug in the electrosprayed nanospherule. Increases were observed as the PVP/drug ratio increased to 4:1, but higher ratios gave no significant increases. In particular, an electrosprayed nanospherule composed of fenofibrate, PVP, and Labrafil M 2125 at the weight ratio of 1:4:0.5 resulted in a particle size of water-soluble fenofibrate.

  11. Lipid nanoparticles for the delivery of poorly water-soluble drugs.

    Science.gov (United States)

    Bunjes, Heike

    2010-11-01

    This review discusses important aspects of lipid nanoparticles such as colloidal lipid emulsions and, in particular, solid lipid nanoparticles as carrier systems for poorly water-soluble drugs, with a main focus on the parenteral and peroral use of these carriers. A short historical background of the development of colloidal lipid emulsions and solid lipid nanoparticles is provided and their similarities and differences are highlighted. With regard to drug incorporation, parameters such as the chemical nature of the particle matrix and the physicochemical nature of the drug, effects of drug partition and the role of the particle interface are discussed. Since, because of the crystalline nature of their lipid core, solid lipid nanoparticles display some additional important features compared to emulsions, their specificities are introduced in more detail. This mainly includes their solid state behaviour (crystallinity, polymorphism and thermal behaviour) and the consequences of their usually non-spherical particle shape. Since lipid nanoemulsions and -suspensions are also considered as potential means to alter the pharmacokinetics of incorporated drug substances, some underlying basic considerations, in particular concerning the drug-release behaviour of such lipid nanodispersions on dilution, are addressed as well. Colloidal lipid emulsions and solid lipid nanoparticles are interesting options for the delivery of poorly water-soluble drug substances. Their specific physicochemical properties need, however, to be carefully considered to provide a rational basis for their development into effective carrier systems for a given delivery task. © 2010 The Author. Journal compilation © 2010 Royal Pharmaceutical Society of Great Britain.

  12. Laser incising of wood: Impregnation of columns with water-soluble dye

    International Nuclear Information System (INIS)

    Hattori, N.; Ando, K.; Kitayama, S.; Nakamura, Y.

    1994-01-01

    To know whether or not laser incising is a useful pre-treatment technique in impregnating a chemical fluid into lumber, pin holes were made in columns of hinoki (Chamaecyparis obtusa Endl.), sugi (Cryptomeria japonica D. Don), karamatsu (Larix leptolepis Gordon) and douglas-fir (Pseudo-tsuga menziesii Franco) with 1.7 kW CO2 laser, and a water-soluble dye was impregnated into these columns with a local pressure impregnation device. Retentions, and lengths and widths of penetrations from each hole were measured quantitatively. Referring to the results of the preparatory experiment mentioned above, incising patterns for sugi and douglas-fir were designed, and the same water-soluble dye was impregnated into the laser-incised columns as well as into non-incised ones with the vacuum-pressure method to obtain penetrated layers with the target depths completely. As a result, a retention of 200 kg/m3 of dye could be achieved for a column of douglas-fir even if it is a species difficult to impregnate. The penetrated layer also could be formed completely at the depth of the laser incision. Therefore, it is concluded that laser incising can be used for the pre-treatment before impregnation of wood columns. (author)

  13. Homogeneous synthesis of Ag nanoparticles-doped water-soluble cellulose acetate for versatile applications.

    Science.gov (United States)

    Cao, Jie; Sun, Xunwen; Zhang, Xinxing; Lu, Canhui

    2016-11-01

    We report a facile and efficient approach for synthesis of well-dispersed and stable silver nanoparticles (Ag NPs) using water-soluble cellulose acetate (CA) as both reductant and stabilizer. Partially substituted CA with highly active hydroxyl groups and excellent water-solubility is able to reduce silver ions in homogeneous aqueous medium effectively. The synthesized Ag NPs were characterized by UV-vis spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and energy dispersive X-ray spectroscope analysis. The as-prepared Ag NPs were well-dispersed, showing a surface plasmon resonance peak at 426nm. The resulted Ag NPs@CA nanohybrids exhibit high catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH 4 . Meanwhile, the nanohybrids are also effective in inhibiting the growth of bacterial. This environmentally friendly method promotes the use of renewable natural resources to prepare a variety of inorganic-organic materials for catalysis, antibacterial, sensors and other applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Direct encapsulation of water-soluble drug into silica microcapsules for sustained release applications

    International Nuclear Information System (INIS)

    Wang Jiexin; Wang Zhihui; Chen Jianfeng; Yun, Jimmy

    2008-01-01

    Direct encapsulation of water-soluble drug into silica microcapsules was facilely achieved by a sol-gel process of tetraethoxysilane (TEOS) in W/O emulsion with hydrochloric acid (HCl) aqueous solution containing Tween 80 and drug as well as cyclohexane solution containing Span 80. Two water-soluble drugs of gentamicin sulphate (GS) and salbutamol sulphate (SS) were chosen as model drugs. The characterization of drug encapsulated silica microcapsules by scanning electronic microscopy (SEM), FTIR, thermogravimetry (TG) and N 2 adsorption-desorption analyses indicated that drug was successfully entrapped into silica microcapsules. The as-prepared silica microcapsules were uniform spherical particles with hollow structure, good dispersion and a size of 5-10 μm, and had a specific surface area of about 306 m 2 /g. UV-vis and thermogravimetry (TG) analyses were performed to determine the amount of drug encapsulated in the microcapsules. The BJH pore size distribution (PSD) of silica microcapsules before and after removing drug was examined. In vitro release behavior of drug in simulated body fluid (SBF) revealed that such system exhibited excellent sustained release properties

  15. Water-soluble contrast media compared with barium in enteric follow-through

    International Nuclear Information System (INIS)

    Laerum, F.; Stordahl, A.; Aase, S.

    1988-01-01

    The local effects and radiographic efficacy of 4 water-soluble contrast media, barium and saline were evaluated in 86 anaesthetized rats with the distal ileum ligated. The rats were observed for 8 hours after instillation of 3 ml of the test substance via orogastric tube. Radiographs were taken after 1, 4 and 8 hours of observation. After 8 hours the intestines were weighed and biopsied for light microscopy, and blood and urine were sampled for testing. Sodium diatrizoate caused increased fluid influx to the bowel lumen and, like barium, provided poorer radiographic images as compared with iohexol, ioxaglate or iodixanol. Barium showed slower progression through the small bowel than the other agents, while sodium diatrizoate was the most rapidly progressing contrast medium and caused the greatest distension. Correlation to osmolality was obvious. No significant morphologic effects on the small bowel mucosa were seen in any of the groups. Low-osmolar, water-soluble contrast media may have prospects for clinical use in patients with suspected small bowel obstruction. (orig.)

  16. Liposomal buccal mucoadhesive film for improved delivery and permeation of water-soluble vitamins.

    Science.gov (United States)

    Abd El Azim, Heba; Nafee, Noha; Ramadan, Alyaa; Khalafallah, Nawal

    2015-07-05

    This study aims at improving the buccal delivery of vitamin B6 (VB6) as a model highly water-soluble, low permeable vitamin. Two main strategies were combined; first VB6 was entrapped in liposomes, which were then formulated as mucoadhesive film. Both plain and VB6-loaded liposomes (LPs) containing Lipoid S100 and propylene glycol (∼ 200 nm) were then incorporated into mucoadhesive film composed of SCMC and HPMC. Results showed prolonged release of VB6 (72.65%, T50% diss 105 min) after 6h from LP-film compared to control film containing free VB6 (96.37%, T50% diss 30 min). Mucoadhesion was assessed both ex vivo on chicken pouch and in vivo in human. Mucoadhesive force of 0.2N and residence time of 4.4h were recorded. Ex vivo permeation of VB6, across chicken pouch mucosa indicated increased permeation from LP-systems compared to corresponding controls. Interestingly, incorporation of the vesicles in mucoadhesive film reduced the flux by 36.89% relative to LP-dispersion. Meanwhile, both films provided faster initial permeation than the liquid forms. Correlating the cumulative percent permeated ex vivo with the cumulative percent released in vitro indicated that LPs retarded VB6 release but improved permeation. These promising results represent a step forward in the field of buccal delivery of water-soluble vitamins. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Simultaneous detection of water-soluble vitamins using the High Performance Liquid Chromatography (HPLC - a review

    Directory of Open Access Journals (Sweden)

    Rosemond Godbless Dadzie

    2014-01-01

    Full Text Available The water-soluble vitamins (WSV: ascorbic acid (vitamin C, thiamine (B1, riboflavin (B2, niacin (B3, panthothenic acid (B5, pyridoxine, and pyridoxal (B6, folic acid (B9, biotin(B8 , and B12 are very essential in the diet of humankind. As a result of ever increasing pressures from both consumers and legal enforcers, to specify accurately nutritive compositions of WSV that are present in food materials, many researchers have attempted to fill this niche through the provision of highly sensitive and rapid high performance liquid chromatography (HPLC procedures. In view of the health benefits of WSV, a replete of HPLC methods have been developed for simultaneous determination of their contents in nature and fortified food samples, nutritional supplements, as well as blood plasmas. The rate of losses of these vitamins during food processing and analysis, in addition to their transient dynamics, presents complexities in developing a highly sensitive HPLC procedure for their simultaneous separations and assays. This review critically assesses the different HPLC procedures developed by researchers and available in the open literature for simultaneous determination of water-soluble vitamins (WSV in dried tropical fruits materials. The study revealed that not a single chromatographic run developed by researchers can simultaneously elute all the WSV at a time. However, the HPLC procedures that are capable of determining all the WSV were coupled with electrospray ionization mass spectroscopy (ESI-MS, thus making the set-up expensive.

  18. HILIC separation and quantitation of water-soluble vitamins using diol column.

    Science.gov (United States)

    Karatapanis, Andreas E; Fiamegos, Yiannis C; Stalikas, Constantine D

    2009-04-01

    Hydrophilic interaction liquid-chromatography (HILIC) in conjunction with diode array detection has been applied for the separation of selected-water-soluble vitamins using an end-capped HILIC-diol column. Vitamins with significant biological importance, such as thiamine (B(1)), riboflavin (B(2)), nicotinic acid (B(3)), nicotinamide (B(3)), pyridoxine (B(6)), folic acid (B(9)), cyanocobalamin (B(12)) and ascorbic acid (vitamin C) were simultaneously separated. Chromatographic conditions including type and percentage of organic modifier in the mobile phase, pH, type and concentration of buffer salt and flow rate were investigated. ACN was shown to offer superior separation for the compounds tested as compared to methanol, isopropanol and THF. Isocratic separation and analysis were achieved for six vitamins (B(1), B(2), nicotinic acid/nicotinamide, B(6) and C) at ACN-H(2)O 90:10, containing ammonium acetate 10 mM, triethylamine 20 mM, pH 5.0, using a flow rate of 0.8 mL/min, while a gradient was necessary to resolve a mixture of all eight water-soluble vitamins. The HILIC method was validated and successfully applied to the analysis of a pharmaceutical formulation and an energy drink negating the need for time consuming clean-up steps.

  19. Chemical constituents: water-soluble vitamins, free amino acids and sugar profile from Ganoderma adspersum.

    Science.gov (United States)

    Kıvrak, İbrahim

    2015-01-01

    Ganoderma adspersum presents a rigid fruiting body owing to chitin content and having a small quantity of water or moisture. The utility of bioactive constituent of the mushroom can only be available by extraction for human usage. In this study, carbohydrate, water-soluble vitamin compositions and amino acid contents were determined in G. adspersum mushroom. The composition in individual sugars was determined by HPLC-RID, mannitol (13.04 g/100 g) and trehalose (10.27 g/100 g) being the most abundant sugars. The examination of water-soluble vitamins and free amino acid composition was determined by UPLC-ESI-MS/MS. Essential amino acid constituted 67.79% of total amino acid, which is well worth the attention with regard to researchers and consumers. In addition, G. adspersum, which is also significantly rich in B group vitamins and vitamin C, can provide a wide range of notable applications in the pharmaceutics, cosmetics, food and dietary supplement industries. G. adspersum revealed its value for pharmacy and nutrition fields.

  20. Synthesis and Characterization of Water-soluble Conjugates of Cabazitaxel Hemiesters-Dextran.

    Science.gov (United States)

    Parhizkar, Elahehnaz; Ahmadi, Fatemeh; Daneshamouz, Saeid; Mohammadi-Samani, Soliman; Sakhteman, Amirhossein; Parhizkar, Golnaz

    2017-11-24

    Cabazitaxel (CTX) is a second- generation taxane derivative, a class of potent anticancer drugs with very low water solubility. CTX is used in patients with resistant prostate cancer unresponsive to the first generation taxane, docetaxel. Currently marketed formulations of CTX contain high concentrations of surfactant and ethanol, which cause severe hypersensitivity reactions in patients. In order to increase its solubility, two hemiester analogs; CTX-succinate and CTX-glutarate were synthesized and characterized. To improve the solubility of hemiesters even more, dextran as a biocompatible polymer was also conjugated to hemiester analogs. MTT assay was performed on MCF-7 cell line to evaluate the cytotoxicity effect of hemiesters and conjugates. Based on the results, hemiester analogs increased water solubility of the drug up to about 3 and 8 fold. Conjugation to dextran enhanced the CTX solubility to more than 1500 fold. These conjugates released the conjugated CTX in less than 24 hours in a pH dependent manner and showed proper hemocompatibility characteristics. The hemiesters had approximately similar cytotoxicity in comparison with CTX and the dextran conjugates showed higher cytotoxicity effect on MCF-7 cell line. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. An experimental study on tissue damage following subcutaneous injection of water soluble contrast media

    International Nuclear Information System (INIS)

    Kim, Seung Hyup; Park, Jae Hyung; Kang, Heung Sik; Kim, Chu Wan; Han, Man Chung; Kim, Yong Il

    1989-01-01

    The water soluble contrast media cause tissue necrosis infrequently by extravasation during intravenous injection in various radiological examinations. However, it has not been well documented that what kind and what concentration of contrast media can cause tissue necrosis. And also, the mechanism of tissue necrosis by extravasated contrast media has not been well known. The purpose of this experimental study was to evaluate the frequency and severity of tissue damage following subcutaneous injection of various water soluble contrast media to investigate the characteristics of the contrast media acting on the tissue damage, and to provide the basic data for the clinical application. Meglumine ioxithalamate,sodium and meglumine ioxithalamate, iopromide, iopamidol, ioxaglate,meglumine diatrizoate and sodium diatrizoate of various iodine content and osmolality were injected into subcutaneous tissue of the dorsum of 970 feet of 485 rats. The tissue reaction of injection sites were grossly examined with period from 1 day to 8 weeks after the injection. Representative gross changes were correlated with histologic findings. The results were as follows; 1. The basic tissue damage by extravasated contrast media was acute and chronic inflammatory reaction of the soft tissue with subsequent progress into the hemorrhagic and necrotizing lesion. 2. Lager volume of contrast media caused more severe tissue damage. 3. Contrast media of higher osmolality caused more severe tissue damage. 4. At same osmolality, contrast media of higher iodine content caused more severe tissue damage

  2. An experimental study on MRI signal intensity vs concentration of water-soluble contrast media

    International Nuclear Information System (INIS)

    Lee, Ghi Jai; Han, Chang Yul; Chang, Kee Hyun; Han, Moon Hee; Han, Man Chung

    1991-01-01

    There has been only one report that water-soluble contrast media containing iodine and used in conventional X -ray radiography reduce T1-and T2-relaxation times. We evaluated the relationship between signal intensity (relative signal intensity to normal saline) and T2-relaxation time of MRI and the concentration of 3 water-soluble contrast media [meglumine ioxithalamate (Telebrix 30), iopromide (Ultravist 300), iotrolan (Isovist 300)] through the phantom study, using both 2.0T and 0.5T MR units. We found that the signal intensity increased significantly on the T1-weighted images as the concentration of contrast media increased. The degree of the increase was larger on 0.5T MR than on 2.0T MR. The signal intensity on proton density image showed no significant difference at various concentrations. However, there were significant decreases of both signal intensity on the T2-weighted images and T2-relaxation time as the concentration of contrast media increased, which was more prominent on 2.0T MR than 0.5T MR. Between the contrast media of the same concentration, there was no significant difference in signal intensity and T2-relaxation time

  3. Spray Freeze-drying - The Process of Choice for Low Water Soluble Drugs?

    International Nuclear Information System (INIS)

    Leuenberger, H.

    2002-01-01

    Most of the novel highly potent drugs, developed on the basis of modern molecular medicine, taking into account cell surface recognition techniques, show poor water solubility. A chemical modification of the drug substance enhancing the solubility often decreases the pharmacological activity. Thus, as an alternative an increase of the solubility can be obtained by the reduction of the size of the drug particles. Unfortunately, it is often difficult to obtain micro or nanosized drug particles by classical or more advanced crystallization using supercritical gases or by milling techniques. In addition, nanosized particles are often not physically stable and need to be stabilized in an appropriate matrix. Thus, it may be of interest to manufacture directly nanosized drug particles stabilized in an inert hydrophilic matrix, i.e. nanostructured and nanocomposite systems. Solid solutions and solid dispersions represent nanostructured and nanocomposite systems. In this context, the use of the vacuum-fluidized-bed technique for the spray-drying of a low water soluble drug cosolubilized with a hydrophilic excipient in a polar organic solvent is discussed. In order to avoid the use of organic solvents, a special spray-freeze-drying technique working at atmospheric pressure is presented. This process is very suitable for temperature and otherwise sensitive drugs such as pharmaproteins

  4. Water-Soluble Dried Blood Spot in Protein Analysis: A Proof-of-Concept Study.

    Science.gov (United States)

    Rosting, Cecilie; Gjelstad, Astrid; Halvorsen, Trine Grønhaug

    2015-08-04

    In the present work human chorionic gonadotropin (hCG) was used as a model protein in a proof-of-concept study combining water-soluble dried blood spot (DBS) material in liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based protein analysis. A water-soluble material consisting of commercially available carboxymethyl cellulose (CMC) was evaluated as sampling material for this purpose. The material dissolved readily at physiological pH. Different sample preparation methods were evaluated, and in the final method, 15 μL of whole blood was deposited and dried on CMC before the whole spot was dissolved prior to cleanup by immunoaffinity extraction, tryptic digest, and preconcentration by solid-phase extraction (SPE). The results indicated complete dissolution of hCG from the spots, acceptable limit of detection (LOD) (0.1 IU/mL), linearity (R(2) = 0.959), accuracy (16%), and precision (≤22%). Long-term stability (45 days) of hCG in dried spots at reduced temperatures (≤8 °C) was also demonstrated. The analyte recovery was comparable to the commercially available nonsolvable cellulose material (FTA DMPK-C card).

  5. The isolation of water-soluble radionuclides from deteriorating spent nuclear fuel in zeolite cartridge

    International Nuclear Information System (INIS)

    Hassan, N.M.; Thompson, M.C.

    1996-01-01

    A method of isolating water-soluble radionuclides leaching from deteriorating spent nuclear fuel by ion-exchange in zeolite cartridges has been studied. Design calculations of two zeolite cartridges to be incorporated in typical spent fuel storage bundle have been provided. Equilibrium exchange data obtained at several temperatures have shown that the maximum exchange capacity of total cesium in sodium titanium aluminosilicate was 114 mg/g zeolite and the capacity at 95% exchange for radioactive isotope Cs-137 was calculated as 55.2 mg/g zeolite. The kinetic data suggest that the rate of exchange of Cs + in sodium titanium aluminosilicate zeolite takes place by a fast initial exchange step followed by slow diffusion of cesium cations. Design calculations based on the equilibrium exchange data show that water-soluble radionuclides leaching from Mk 31 slugs can be isolated using two zeolite cartridges, each 3.7 inches in inside diameter and 2.5 inches in length. The cartridges are designed to isolate 95% of the Cs + leaching from the spent fuel storage bundle. The results from the thermal induced convective flow tests indicate that the system will provide necessary cooling to the spent fuel by convective currents while isolating the Cs + leaching from spent fuel storage bundle in the cartridges

  6. Early-life supplementation of vitamins A and D, in water-soluble form or in peanut oil, and allergic diseases during childhood.

    Science.gov (United States)

    Kull, Inger; Bergström, Anna; Melén, Erik; Lilja, Gunnar; van Hage, Marianne; Pershagen, Göran; Wickman, Magnus

    2006-12-01

    Early vitamin supplementation is given routinely to infants in many countries, but it is unclear whether this affects the risk of allergic diseases. We sought to study the association between early-life supplementation of vitamins A and D in water-soluble form or in peanut oil and allergic diseases up to 4 years of age. A prospective birth cohort of 4089 newborn infants was followed for 4 years using parental questionnaires repeatedly to collect information on exposure and health. At 4 years, the response rate was 90%, and allergen-specific IgE levels to food and airborne allergens were measured in 2614 of the participating children. Vitamins A and D were given to 98% of the children in infancy, and vitamins based in peanut oil dominated (90%). Children supplemented with vitamins A and D in water-soluble form during the first year of life had an almost 2-fold increased risk of asthma (adjusted odds ratio [OD], 2.18; 95% CI, 1.45-3.28), food hypersensitivity (adjusted OR, 1.89; 95% CI, 1.33-2.65), and sensitization to common food and airborne allergens (adjusted OR, 1.88; 95% CI, 1.34-2.64) at age 4 years compared with those receiving vitamins in peanut oil. No increased risk of IgE antibodies to peanut was seen in children receiving vitamins in peanut oil. Supplementation of vitamins A and D in water-soluble form seems to increase the risk of allergic disease up to the age of 4 years compared with supplementation with the same vitamins given in peanut oil. Vitamins A and D in oil does not seem to increase the risk of allergic disease during childhood.

  7. Improved intestinal absorption of a poorly water-soluble oral drug using mannitol microparticles containing a nanosolid drug dispersion.

    Science.gov (United States)

    Nishino, Yukiko; Kubota, Aya; Kanazawa, Takanori; Takashima, Yuuki; Ozeki, Tetsuya; Okada, Hiroaki

    2012-11-01

    A nozzle for a spray dryer that can prepare microparticles of water-soluble carriers containing various nanoparticles in a single step was previously developed in our laboratory. To enhance the solubility and intestinal absorption of poorly water-soluble drugs, we used probucol (PBL) as a poorly water-soluble drug, mannitol (MAN) as a water-soluble carrier for the microparticles, and EUDRAGIT (EUD) as a polymer vehicle for the solid dispersion. PBL-EUD-acetone-methanol and aqueous MAN solutions were simultaneously supplied through different liquid passages of the spray nozzle and dried together. PBL-EUD solid dispersion was nanoprecipitated in the MAN solution using an antisolvent mechanism and rapidly dried by surrounding it with MAN. PBL in the dispersion vehicle was amorphous and had higher physical stability according to powder X-ray diffraction and differential scanning calorimetry analysis. The bioavailability of PBL in PBL-EUD S-100-MAN microparticles after oral administration in rats was markedly higher (14- and 6.2-fold, respectively) than that of the original PBL powder and PBL-MAN microparticles. These results demonstrate that the composite microparticles containing a nanosized solid dispersion of a poorly water-soluble drug prepared using the spray nozzle developed by us should be useful to increase the solubility and bioavailability of drugs after oral administration. Copyright © 2012 Wiley Periodicals, Inc.

  8. One-step synthesis and antibacterial property of water-soluble silver nanoparticles by CGJ bio-template

    International Nuclear Information System (INIS)

    Zhu Zichun; Wu Qingsheng; Chen Ping; Yang Xiaohong

    2011-01-01

    In this article, a new synthetic method of nanoparticles with fresh Chinese gooseberry juice (CGJ) as bio-template was developed. One-step synthesis of highly water-soluble silver nanoparticles at room temperature without using any harmful reducing agents and special capping agent was fulfilled with this method. In the process, the products were obtained by adding AgNO 3 to CGJ, which was used as reducing agent, capping agent, and the bio-template. The products of silver nanoparticles with diameter of 10–30 nm have strong water solubility and excellent antibiotic function. With the same concentration 0.047 μg mL −1 , the antibacterial effect of water-soluble silver particles by fresh CGJ was 53%, whereas only 27% for silver nanoparticles synthesized using the template method of fresh onion inner squama coat (OISC). The excellent water solubility of the products would enable them have better applications in the bio-medical field. The synthetic method would also have potential application in preparing other highly water-soluble particles, because of its simple apparatus, high yield, mild conditions, and facile operation.

  9. Relationship Between Urinary Concentrations of Nine Water-soluble Vitamins and their Vitamin Intakes in Japanese Adult Males.

    Science.gov (United States)

    Shibata, Katsumi; Hirose, Junko; Fukuwatari, Tsutomu

    2014-01-01

    Excess water-soluble vitamins are thought to be eliminated in the urine. We have reported a strong relationship between water-soluble vitamin intake and urinary excretion in females. The relationship, however, is not well understood in males. In the present experiment, 10 Japanese male subjects were given a standard Japanese diet for the first week. The subjects remained on the same diet, and a synthesized water-soluble vitamin mixture containing one time the Dietary Reference Intakes (DRIs) for Japanese was given for the second week, three times the DRIs for the third week, and six times the DRIs for the fourth week. Twenty-four-hour urine samples were collected each week. Urinary excretion levels for seven of the nine water-soluble vitamin levels, excluding vitamin B12 and folate, increased linearly and sharply in a dose-dependent manner. These results suggest that measuring urinary water-soluble vitamins can be good nutritional markers for assessing vitamin intakes in humans.

  10. Relationship between Urinary Concentrations of Nine Water-soluble Vitamins and their Vitamin Intakes in Japanese Adult Males

    Directory of Open Access Journals (Sweden)

    Katsumi Shibata

    2014-01-01

    Full Text Available Excess water-soluble vitamins are thought to be eliminated in the urine. We have reported a strong relationship between water-soluble vitamin intake and urinary excretion in females. The relationship, however, is not well understood in males. In the present experiment, 10 Japanese male subjects were given a standard Japanese diet for the first week. The subjects remained on the same diet, and a synthesized water-soluble vitamin mixture containing one time the Dietary Reference Intakes (DRIs for Japanese was given for the second week, three times the DRIs for the third week, and six times the DRIs for the fourth week. Twenty-four-hour urine samples were collected each week. Urinary excretion levels for seven of the nine water-soluble vitamin levels, excluding vitamin B 12 and folate, increased linearly and sharply in a dose-dependent manner. These results suggest that measuring urinary water-soluble vitamins can be good nutritional markers for assessing vitamin intakes in humans.

  11. Antimicrobial and Antifungal Effects of Acid and Water-Soluble Chitosan Extracted from Indian Shrimp (Fenneropenaeus indicus Shell

    Directory of Open Access Journals (Sweden)

    Ali Taheri

    2013-06-01

    Full Text Available Background & Objective : Currently, efforts are underway to seek new and effective antimicrobial agents, and marine resources are potent candidates for this aim. The following study was conducted to investigate the efficacy of water-soluble and acid-soluble chitosan against some pathogenic organisms.   Materials & Method s: Inhibition zone of different concentrations (5, 7.5, and 10 mg/ml of acid- soluble and water-soluble chitosan were examined for in vitro antibacterial activity against 4 kinds of hospital bacteria and penicillium sp. Results were compared with 4 standard antibiotics: streptomycin, gentamicin, tetracycline, and erythromycin. Furthermore, minimum inhibitory concentration and minimum lethal concentration were determined.   Results: Inhibition activity of acid-soluble chitosan (10% showed the best result (p value < 0.05, whereas water-soluble chitosan exhibited the least antibacterial effects (p value < 0.05. Chitosan demonstrated maximum effect on V. cholera cerotype ogava , and the least effect was seen on E. coli (p value < 0.05. Acid-soluble chitosan had a more potent effect than the standard antibiotics. Also, acid-soluble chitosan (10% and water-soluble chitosan showed maximum inhibitory effects on penicillium sp.   Conclusion: Chitosan showed maximum antibacterial effect against S. aureus, V. cholerae cerotype ogava, and water-soluble chitosan demonstrated good antifungal effects, revealing a statistically significant difference with common antibacterial and antifungal medicines.

  12. Sunlight creates oxygenated species in water-soluble fractions of Deepwater horizon oil

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Phoebe Z. [Department of Chemistry, University of New Orleans, New Orleans, LA 70148 (United States); Chen, Huan [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Podgorski, David C. [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Future Fuels Institute, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); McKenna, Amy M. [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Tarr, Matthew A., E-mail: mtarr@uno.edu [Department of Chemistry, University of New Orleans, New Orleans, LA 70148 (United States)

    2014-09-15

    Graphical abstract: Sunlight oxygenates petroleum. - Highlights: • Oxidation seen in water-soluble oil fraction after exposure to simulated sunlight. • Oxygen addition occurred across a wide range of carbon number and DBE. • Oil compounds were susceptible to addition of multiple oxygens to each molecule. • Results provide understanding of fate of oil on water after exposure to sunlight. - Abstract: In order to assess the impact of sunlight on oil fate, Macondo well oil from the Deepwater Horizon (DWH) rig was mixed with pure water and irradiated with simulated sunlight. After irradiation, the water-soluble organics (WSO) from the dark and irradiated samples were extracted and characterized by ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Liquid–liquid extraction yielded two fractions from dark and irradiated water/oil mixtures: acidic WSOs (negative-ion electrospray (ESI)), and base/neutral WSOs (positive-ion ESI) coupled to FT-ICR MS to catalog molecular-level transformations that occur to Macondo-derived WSOs after solar irradiation. Such direct measure of oil phototransformation has not been previously reported. The most abundant heteroatom class detected in the irradiated WSO acid fractions correspond to molecules that contain five oxygens (O{sub 5}), while the most abundant acids in the dark samples contain two oxygen atoms per molecule (O{sub 2}). Higher-order oxygen classes (O{sub 5}–O{sub 9}) were abundant in the irradiated samples, but <1.5% relative abundance in the dark sample. The increased abundance of higher-order oxygen classes in the irradiated samples relative to the dark samples indicates that photooxidized components of the Macondo crude oil become water-soluble after irradiation. The base/neutral fraction showed decreased abundance of pyridinic nitrogen (N{sub 1}) concurrent with an increased abundance of N{sub 1}O{sub x} classes after irradiation. The predominance of higher

  13. Determination of the design space of the HPLC analysis of water-soluble vitamins.

    Science.gov (United States)

    Wagdy, Hebatallah A; Hanafi, Rasha S; El-Nashar, Rasha M; Aboul-Enein, Hassan Y

    2013-06-01

    Analysis of water-soluble vitamins has been tremendously approached through the last decades. A multitude of HPLC methods have been reported with a variety of advantages/shortcomings, yet, the design space of HPLC analysis of these vitamins was not defined in any of these reports. As per the food and drug administration (FDA), implementing the quality by design approach for the analysis of commercially available mixtures is hypothesized to enhance the pharmaceutical industry via facilitating the process of analytical method development and approval. This work illustrates a multifactorial optimization of three measured plus seven calculated influential HPLC parameters on the analysis of a mixture containing seven common water-soluble vitamins (B1, B2, B6, B12, C, PABA, and PP). These three measured parameters are gradient time, temperature, and ternary eluent composition (B1/B2) and the seven calculated parameters are flow rate, column length, column internal diameter, dwell volume, extracolumn volume, %B (start), and %B (end). The design is based on 12 experiments in which, examining of the multifactorial effects of these 3 + 7 parameters on the critical resolution and selectivity, was carried out by systematical variation of all these parameters simultaneously. The 12 basic runs were based on two different gradient time each at two different temperatures, repeated at three different ternary eluent compositions (methanol or acetonitrile or a mixture of both). Multidimensional robust regions of high critical R(s) were defined and graphically verified. The optimum method was selected based on the best resolution separation in the shortest run time for a synthetic mixture, followed by application on two pharmaceutical preparations available in the market. The predicted retention times of all peaks were found to be in good match with the virtual ones. In conclusion, the presented report offers an accurate determination of the design space for critical resolution in the

  14. Complex rheological properties of a water-soluble extract from the fronds of the black tree fern, Cyathea medullaris.

    Science.gov (United States)

    Goh, Kelvin K T; Matia-Merino, Lara; Hall, Christopher E; Moughan, Paul J; Singh, Harjinder

    2007-11-01

    A water-soluble extract was obtained from the fronds of a New Zealand native black tree fern (Cyathea medullaris or Mamaku in Māori). The extract exhibited complex rheological behavior. Newtonian, shear-thinning, shear-thickening, thixotropic, antithixotropic, and viscoelastic behaviors were observed depending on polymer concentration, shear rate, and shear history. The extract also displayed rod-climbing and self-siphoning properties typical of viscoelastic fluids. Such complex rheological properties have been reported in synthetic or chemically modified polymers but are less frequent in unmodified biopolymers. Although Mamaku extract obtained from the pith of the fern has been traditionally used by the Māori in New Zealand for treating wounds and diarrhea among other ailments, this material has never been characterized before. This study reports on the chemical composition of the extract and on its viscoelastic properties through rotational and oscillatory rheological measurements. Explanations of the mechanism behind the rheological properties were based on transient network models for associating polymers.

  15. Dissolution of Monocrystalline Silicon Nanomembranes and Their Use as Encapsulation Layers and Electrical Interfaces in Water-Soluble Electronics.

    Science.gov (United States)

    Lee, Yoon Kyeung; Yu, Ki Jun; Song, Enming; Barati Farimani, Amir; Vitale, Flavia; Xie, Zhaoqian; Yoon, Younghee; Kim, Yerim; Richardson, Andrew; Luan, Haiwen; Wu, Yixin; Xie, Xu; Lucas, Timothy H; Crawford, Kaitlyn; Mei, Yongfeng; Feng, Xue; Huang, Yonggang; Litt, Brian; Aluru, Narayana R; Yin, Lan; Rogers, John A

    2017-12-26

    The chemistry that governs the dissolution of device-grade, monocrystalline silicon nanomembranes into benign end products by hydrolysis serves as the foundation for fully eco/biodegradable classes of high-performance electronics. This paper examines these processes in aqueous solutions with chemical compositions relevant to groundwater and biofluids. The results show that the presence of Si(OH) 4 and proteins in these solutions can slow the rates of dissolution and that ion-specific effects associated with Ca 2+ can significantly increase these rates. This information allows for effective use of silicon nanomembranes not only as active layers in eco/biodegradable electronics but also as water barriers capable of providing perfect encapsulation until their disappearance by dissolution. The time scales for this encapsulation can be controlled by introduction of dopants into the Si and by addition of oxide layers on the exposed surfaces.The former possibility also allows the doped silicon to serve as an electrical interface for measuring biopotentials, as demonstrated in fully bioresorbable platforms for in vivo neural recordings. This collection of findings is important for further engineering development of water-soluble classes of silicon electronics.

  16. Relation of zinc levels and water soluble phosphorus in suphala [fertilizer] on uptake of phosphorus and zinc

    International Nuclear Information System (INIS)

    Mutatkar, V.K.; Chapke, V.G.

    1975-01-01

    Under pot culture, four levels of Zn 0, 2, 4 and 6 ppm, were studied in relation to 30, 50 and 100 % water soluble levels of phosphorus in suphala for the dry matter production and uptake of P and Zn by maize on acidic soil of Goa and black cotton soil of Maharashtra. 32 P and 65 Zn tracers were used for this investigation. The results revealed that application of Zn has increased the dry matter and uptake of phosphorus upto 4 ppm of Zn application and it has decreased at 6 ppm Zn level. This inhibition of P uptake was observed at all water soluble levels of P and in both the soils studied. Zn uptake by maize in both the soils under study was increased with increasing level of Zn, irrespective of water soluble level of P in suphala. (author)

  17. Impact of Conventional and Integrated Management Systems on the Water-Soluble Vitamin Content in Potatoes, Field Beans, and Cereals.

    Science.gov (United States)

    Freitag, Sabine; Verrall, Susan R; Pont, Simon D A; McRae, Diane; Sungurtas, Julia A; Palau, Raphaëlle; Hawes, Cathy; Alexander, Colin J; Allwood, J William; Foito, Alexandre; Stewart, Derek; Shepherd, Louise V T

    2018-01-31

    The reduction of the environmental footprint of crop production without compromising crop yield and their nutritional value is a key goal for improving the sustainability of agriculture. In 2009, the Balruddery Farm Platform was established at The James Hutton Institute as a long-term experimental platform for cross-disciplinary research of crops using two agricultural ecosystems. Crops representative of UK agriculture were grown under conventional and integrated management systems and analyzed for their water-soluble vitamin content. Integrated management, when compared with the conventional system, had only minor effects on water-soluble vitamin content, where significantly higher differences were seen for the conventional management practice on the levels of thiamine in field beans (p water-soluble vitamin content of the crops analyzed here.

  18. ADME-Tox profiling of some low molecular weight water soluble chitosan derivatives

    Directory of Open Access Journals (Sweden)

    Adriana Isvoran

    2017-09-01

    Full Text Available Within this study we use a few computational tools for predicting absorption, distribution, metabolism, excretion and toxicity (ADME-Tox, pharmacokinetics profiles, toxic/adverse effects, carcinogenicity, cardiotoxicity and endocrine disruption of some of low molecular weight water soluble derivatives of chitosan that are used in wound healing. Investigated compounds do not possess drug-like properties, their pharmacokinetics profiles reveal poor gastrointestinal absorption and low skin penetration. Chitosan derivatives cannot pass the blood-brain barrier and they are not able to inhibit the enzymes of the cytochrome P450 that are involved in the metabolism of xenobiotics. They do not reflect carcinogenicity and cardiotoxicity and reveal only a low probability to be endocrine disruptors. The main side effects in humans of the investigated compounds are: weight loss, acidosis, gastrointestinal toxicity, respiratory failure. This information is especially important for professional exposure and accidental contamination with these compounds.

  19. Effects of water-soluble humic extract and biofertilizer on development of Callophyllum brasiliense seedlings

    Directory of Open Access Journals (Sweden)

    Jader Galba Busato

    2016-06-01

    Full Text Available The objective of this work was to evaluate the effects of water-soluble humic extract (EHSA, Hortbio® biofertilizer (HORT and both compounds combination (EHSA+HORT on vegetative growth, nutrient absorption and chlorophyll levels in guanandi (Callophyllum brasiliense seedlings. Isolated and combined additions of EHSA and HORT did not affect seedlings height, number of leaves, leaf and root dry matter and leaf area during early stages of seedling growth. However, HORT and EHSA+HORT treatments increased chlorophyll levels and total N content. Addition of HORT resulted in S, Zn, Mg, Mn and Cu increases in the seedlings leaves, while ESHA application increased K, Mg, S and B. P and Ca levels were not altered by the treatments, however, addition of EHSA and EHSA+HORT reduced significantly the absorption of Cu, Fe, Mn and Zn.

  20. Highly water-soluble, porous, and biocompatible boron nitrides for anticancer drug delivery.

    Science.gov (United States)

    Weng, Qunhong; Wang, Binju; Wang, Xuebin; Hanagata, Nobutaka; Li, Xia; Liu, Dequan; Wang, Xi; Jiang, Xiangfen; Bando, Yoshio; Golberg, Dmitri

    2014-06-24

    Developing materials for "Nano-vehicles" with clinically approved drugs encapsulated is envisaged to enhance drug therapeutic effects and reduce the adverse effects. However, design and preparation of the biomaterials that are porous, nontoxic, soluble, and stable in physiological solutions and could be easily functionalized for effective drug deliveries are still challenging. Here, we report an original and simple thermal substitution method to fabricate perfectly water-soluble and porous boron nitride (BN) materials featuring unprecedentedly high hydroxylation degrees. These hydroxylated BNs are biocompatible and can effectively load anticancer drugs (e.g., doxorubicin, DOX) up to contents three times exceeding their own weight. The same or even fewer drugs that are loaded on such BN carriers exhibit much higher potency for reducing the viability of LNCaP cancer cells than free drugs.

  1. Micelles from lipid derivatives of water-soluble polymers as delivery systems for poorly soluble drugs.

    Science.gov (United States)

    Lukyanov, Anatoly N; Torchilin, Vladimir P

    2004-05-07

    Polymeric micelles have a whole set of unique characteristics, which make them very promising drug carriers, in particular, for poorly soluble drugs. Our review article focuses on micelles prepared from conjugates of water-soluble polymers, such as polyethylene glycol (PEG) or polyvinyl pyrrolidone (PVP), with phospholipids or long-chain fatty acids. The preparation of micelles from certain polymer-lipid conjugates and the loading of these micelles with various poorly soluble anticancer agents are discussed. The data on the characterization of micellar preparations in terms of their morphology, stability, longevity in circulation, and ability to spontaneously accumulate in experimental tumors via the enhanced permeability and retention (EPR) effect are presented. The review also considers the preparation of targeted immunomicelles with specific antibodies attached to their surface. Available in vivo results on the efficiency of anticancer drugs incorporated into plain micelles and immunomicelles in animal models are also discussed.

  2. Functionally engineered nanosized particles in pharmaceutics: improved oral delivery of poorly water-soluble drugs.

    Science.gov (United States)

    Ozeki, Tetsuya; Tagami, Tatsuaki

    2013-01-01

    The development of drug nanoparticles has attracted substantial attention because of their potential to improve the dissolution rate and oral availability of poorly water-soluble drugs. This review summarizes the recent articles that discussed nanoparticle-based oral drug delivery systems. The preparation methods were categorized as top-down and bottom-up methods, which are common methods for preparing drug nanoparticles. In addition, methods of handling drug nanoparticles (e.g., one-step preparation of nanocomposites which are microparticles containing drug nanoparticles) were introduced for the effective preservation of drug nanoparticles. The carrier-based preparation of drug nanoparticles was also introduced as a potentially promising oral drug delivery system.

  3. Radiation crosslinking of starch/water-soluble polymer blends for hydrogel

    International Nuclear Information System (INIS)

    Hashim, K.; Mohid, N.; Bahari, K.; Dahlan, K.Z.

    2000-01-01

    Water-soluble polymers such as PVP(polyvinyl pyrrolidone) and PVA(polyvinyl alcohol), in aqueous solution can form hydrogel easily upon gamma or electron beam irradiation. The properties of hydrogels, particularly for wound dressing application, can be further improved by adding sago starch to the blend. Results show improved gel strength and elongation properties of the hydrogel with increasing sago concentration. It was found that the PVA/sago hydrogel gives better gel strength and elongation than the PVP/sago hydrogel. The tackiness property of the PVA/sago hydrogel increased with increase amount of sago starch added. In case of PVP/sago hydrogel, the tackiness property shows significant increase with increasing amount of sago except for the 5%PVP composition. The swelling properties of PVP/sago and PVA/sago hydrogel decreased with increasing amount of sago but the crosslink density of the hydrogels also reduced. (author)

  4. Effects of frequency and a radical scavenger on ultrasonic degradation of water-soluble polymers.

    Science.gov (United States)

    Koda, Shinobu; Taguchi, Kimihiko; Futamura, Kazunori

    2011-01-01

    Ultrasonic degradation of methyl cellulose, pullulan, dextran and poly(ethylene oxide) in aqueous solutions was investigated at the frequencies of 20 and 500 kHz, where the ultrasonic power delivered into solutions was kept constant (22 W). The number average molecular mass and the polydispersity were obtained as a function of sonication time. The degradation under sonication at the 500 kHz frequency proceeded faster in comparison with the 20 kHz sonication for four polymers. The addition of a radical scavenger, t-BuOH, resulted in suppression of degradation of water-soluble polymers. The degradation rate constants were estimated from the plot of molecular weight against sonication time. The degradation rate of methyl cellulose was the largest one among the investigated polymers. The difference in the degradation rates was discussed in terms of the flexibility and the hydrodynamic radius of polymer chains in aqueous solutions. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Development and characterization of nanoparticulate formulation of a water soluble prodrug of dexamethasone by HIP complexation.

    Science.gov (United States)

    Gaudana, Ripal; Parenky, Ashwin; Vaishya, Ravi; Samanta, Swapan K; Mitra, Ashim K

    2011-01-01

    The objective of this study was to develop and characterize a nanoparticulate-based sustained release formulation of a water soluble dipeptide prodrug of dexamethasone, valine-valine-dexamethasone (VVD). Being hydrophilic in nature, it readily leaches out in the external aqueous medium and hence partitions poorly into the polymeric matrix resulting in minimal entrapment in nanoparticles. Hence, hydrophobic ion pairing (HIP) complexation of the prodrug was employed with dextran sulphate as a complexing polymer. A novel, solid in oil in water emulsion method was employed to encapsulate the prodrug in HIP complex form in poly(lactic-co-glycolic acid) matrix. Nanoparticles were characterized with respect to size, zeta potential, crystallinity of entrapped drug and surface morphology. A significant enhancement in the entrapment of the prodrug in nanoparticles was achieved. Finally, a simple yet novel method was developed which can also be applicable to encapsulate other charged hydrophilic molecules, such as peptides and proteins.

  6. High sensitive determination of zinc with novel water-soluble small molecular fluorescent sensor

    International Nuclear Information System (INIS)

    Weng Ying; Chen Zilin; Wang Fang; Xue Lin; Jiang Hua

    2009-01-01

    A high sensitive method of quantitative analysis for the determination of zinc in the nutrition supplements has been developed by using a novel water-soluble fluorescent sensor HQ3: (8-pyridylmethyloxy-2-methyl-quinoline). Under the optimized condition of 67 mM phosphate buffer, pH 7.4, and 5% (v/v) DMSO, the zinc concentration showed good linear relationship with fluorescence intensity in the range of 7.5 x 10 -8 to 2.5 x 10 -5 M with the detection limit of 1.5 x 10 -8 M. HQ3 exhibited high selectivity to zinc comparing with other metal ions except for cadmium. The developed analytical method was successfully used for determining the content of zinc in a real sample of zinc gluconate solution of Sanchine.

  7. Aryl-derivatized, water-soluble functionalized carbon nanotubes for biomedical applications

    International Nuclear Information System (INIS)

    Karousis, N.; Ali-Boucetta, H.; Kostarelos, K.; Tagmatarchis, N.

    2008-01-01

    The functionalization of very-thin multi-walled carbon nanotubes (VT-MWNTs) with an aniline derivative, via the protocol of in situ generated aryl diazonium salts results, upon acidic deprotection of the terminal BOC group, on the formation of the water-soluble positively charged ammonium functionalized VT-MWNTs-NH 3 + material. The new materials have been structurally and morphologically characterized by infra-red (ATR-IR) spectroscopy and transmission electron microscopy (TEM). The quantitative calculation of the grafted aryl units onto the skeleton of VT-MWNTs has been estimated by thermogravimetric analysis (TGA), while the quantitative Kaiser test showed the amine group loaded onto VT-MWNTs-NH 3 + material. The aqueous solubility of this material has allowed the performance of some initial toxicological in vitro investigations

  8. Controlled synthesis of titania using water-soluble titanium complexes: A review

    Science.gov (United States)

    Truong, Quang Duc; Dien, Luong Xuan; Vo, Dai-Viet N.; Le, Thanh Son

    2017-07-01

    The development of human society has led to the increase in energy and resources consumption as well as the arising problems of environmental damage and the toxicity to the human health. The development of novel synthesis method which tolerates utilization of toxic solvents and chemicals would fulfill the demand of the society for safer, softer, and environmental friendly technologies. For the past decades, a remarkable progress has been attained in the development of new water-soluble titanium complexes (WSTC) and their use for the synthesis of nanocrystalline titanium dioxide materials by aqueous solution-based approaches. The progress of synthesis of nanocrystalline titanium dioxide using such WSTCs is reviewed in this work. The key structural features responsible for the successfully controlled synthesis of TiO2 are discussed to provide guidelines for the morphology-controlled synthesis. Finally, this review ends with a summary and some perspectives on the challenges as well as new directions in this fascinating research.

  9. Biostimulants and Its Potential Utilization in Functional Water-soluble Fertilizers

    Directory of Open Access Journals (Sweden)

    ZHANG Qiang

    2018-02-01

    Full Text Available Biostimulants are becoming widely applied and extended in the fertilizer industry, because of their effects on soil improvement, anti-stress ability enhancement and root growth promotion, which can increase efficient uptake and utilization of soil nutrients, crop yield and quality.This review introduced the concepts of biostimulants, and summarized the functions and related mechanisms of commonly-applied biostimulants in the market, i.e.humic acid, amino acid, seaweed extracts and plant-growth-promoting bacteria(PGPR. The properties and applied characteristics of different organic wastes containing some biostimulating compounds as the main material of functional water soluble fertilizers (WSFin the industry were presented. The technical keys to compound these organic wastes with some bio-active substances to produce the functional WSF were explored, with the aims to support the value -added utilization of organic wastes, reduce the use of fertilizers, and promote crops忆 quality and quantity.

  10. Ventriculography and cisternography with water-soluble contrast media in infants with myelomeningocele

    International Nuclear Information System (INIS)

    Yamada, H.; Nakamura, S.; Tanaka, Y.; Tajima, M.; Kageyama, N.

    1982-01-01

    Fifty-four newborn infants with myelomeningocele and hydrocephalus were studied by ventriculography using water-soluble contrast media; 20 were also studied by metrizamide myeloencephalography and computerized tomographic (CT) cisternography. Ventriculography suggested that the aqueduct was patent in all cases. Outflow of contrast medium from the fourth ventricle was slow in most cases, complete obstruction was seen in 15%, communication was delayed at the outlet in 54%, and rather free communication was observedin 31%. Metrizamide myeloencephalography and CT cisternography suggested a partial block at the level of the ambient cisterns in approximately one-third of infants. These findings support the concept that flow of cerebrospinal fluid is reduced in several areas. Aqueductal stenosis was not considered an important factor in hydrocephalus, while the most important site of obstruction was felt to be the lowest portion of the fourth ventricle

  11. A new procedure for imaging liver and spleen with water soluble contrast media in liposomes

    International Nuclear Information System (INIS)

    Zherbin, E.A.; Davidenkova, E.F.; Khanson, K.P.; Gubareva, A.V.; Zhdanova, N.V.; Aliyakparov, M.T.; Loshakova, L.V.; Fomina, Eh.V.; Rozenberg, O.A.

    1983-01-01

    The problems of long-term, reversible, and safe contrast investigation of liver and spleen and reduction of the irritating action of water-soluble contrast media on the wall of blood vessels are unresolved. The production and experimental application of contrast media encapsulated in liposomes are described. It is possible to produce a liposome preparation with 10-20 % Verografin content. After intravenous injection it leads to a quick (after 16-30 min), persisting (10-12 h) and reversible (24-30 h) contrast imaging of liver and spleen in rodents. The contrast medium has no pathological effects on heart, blood and circulatory system and on the morphology of liver, spleen, heart, lungs, kidneys and urinary bladder. The perspectives of clinical application of such contrast media are discussed. (author)

  12. Water-soluble thin film transistors and circuits based on amorphous indium-gallium-zinc oxide.

    Science.gov (United States)

    Jin, Sung Hun; Kang, Seung-Kyun; Cho, In-Tak; Han, Sang Youn; Chung, Ha Uk; Lee, Dong Joon; Shin, Jongmin; Baek, Geun Woo; Kim, Tae-il; Lee, Jong-Ho; Rogers, John A

    2015-04-22

    This paper presents device designs, circuit demonstrations, and dissolution kinetics for amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) comprised completely of water-soluble materials, including SiNx, SiOx, molybdenum, and poly(vinyl alcohol) (PVA). Collections of these types of physically transient a-IGZO TFTs and 5-stage ring oscillators (ROs), constructed with them, show field effect mobilities (∼10 cm2/Vs), on/off ratios (∼2×10(6)), subthreshold slopes (∼220 mV/dec), Ohmic contact properties, and oscillation frequency of 5.67 kHz at supply voltages of 19 V, all comparable to otherwise similar devices constructed in conventional ways with standard, nontransient materials. Studies of dissolution kinetics for a-IGZO films in deionized water, bovine serum, and phosphate buffer saline solution provide data of relevance for the potential use of these materials and this technology in temporary biomedical implants.

  13. An unusual feature of uranium ore from Domiasiat, Meghalaya: presence of water soluble uranium

    International Nuclear Information System (INIS)

    Singh, A.K.; Padmanabhan, N.P.H.; Sivaramakrishnan, K.; Krishna Rao, N.

    1993-01-01

    An unusual feature of the recently discovered sandstone-type uranium deposit in Domiasiat is the presence of appreciable amount of water soluble uranium. With normal tap water at its natural pH (7.5-7.8), upto 35% of the uranium in the ore was found to be soluble during agitation in the different samples. Presence of other ions in appreciable quantities particularly SO 4 -2 Cl - and Fe +3 appear to influence the dissolution. Percolation experiments give terminal solubilization of upto 58%, but the instantaneous uranium concentration in the percolating water attains its maximum within the first few minutes of contact. A detailed study on the chemistry of uranium dissolution may throw light on the physico-chemical controls of localization of uranium in the deposit. (author). 7 refs., 3 tabs., 4 tabs

  14. New strategies in actinide separation - water-soluble complexing agents for the innovative SANEX process

    International Nuclear Information System (INIS)

    Ruff, Christian M.; Muelllich, Udo; Geist, Andreas; Panak, Petra J.

    2012-01-01

    Reduction of the radiotoxicity and thermal output of radioactive wastes prior to their permanent disposal is a topic of extreme interest for the issue of final nuclear waste disposal. One possibility to this end is a process referred to as actinide separation. This process can be optimised by means of a newly developed water-soluble molecule, as has been shown in studies on the molecule's complex chemistry using ultra-modern laser-based spectroscopy methods under process-relevant reaction conditions. Through the use of curium (III) and europium (III), which as members of the trivalent actinides and lanthanides family have excellent spectroscopic properties, it has been possible to generate spectroscopic and thermodynamic data which will facilitate our understanding of the complex chemistry and extraction chemistry of this molecule family.

  15. Synthesis, structure, antioxidant activity, and water solubility of trolox ion conjugates

    Directory of Open Access Journals (Sweden)

    Yuliya V. Yushkova

    2018-01-01

    Full Text Available The interaction of trolox with ammonia, alkylamines of different classes, and amino derivatives of heterocyclic compounds, including nitroxyl radicals and alkaloids, led to the production of ammonium salts called ion conjugates (ICs. Five ICs were characterised by X-ray diffraction. This is the first time a wide range of ICs were made from trolox with amines, and ESI-MS data demonstrated they have the potential to generate pseudomolecular [(A−B+ + H]+ ions. For all obtained trolox ICs, a significant increase (1–3 orders of magnitude in water solubility was achieved while retaining high antioxidant activity. ICs synthesised from two biologically active fragments may be used to create polyfunctional agents with varying solubility and bioavailability. Keywords: Trolox, Amines, Ion conjugates, Antioxidants, Mass-spectrometry

  16. Hygroscopic behavior of water-soluble matter in marine aerosols over the East China Sea.

    Science.gov (United States)

    Yan, Yu; Fu, Pingqing; Jing, Bo; Peng, Chao; Boreddy, S K R; Yang, Fan; Wei, Lianfang; Sun, Yele; Wang, Zifa; Ge, Maofa

    2017-02-01

    In this study, we investigated hygroscopic properties of water-soluble matter (WSM) in marine aerosols over the East China Sea, which were collected during a Natural Science Foundation of China (NSFC) sharing cruise in 2014. Hygroscopic growth factors (g) of WSM were measured by a hygroscopicity tandem differential mobility analyzer (H-TDMA) with an initial dry particle mobility diameter of 100nm. The observed g at 90% relative humidity (RH), g(90%) WSM , defined as the ratio of the particle diameter at 90% RH to that at RHsea water was likely due to the transport of anthropogenic aerosols, chemical aging of dust particles, the contribution of biomass burning products, and the aerosol hygroscopic growth inhibition of organics. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Method to produce water-soluble sugars from biomass using solvents containing lactones

    Science.gov (United States)

    Dumesic, James A.; Luterbacher, Jeremy S.

    2017-08-08

    A process to produce an aqueous solution of carbohydrates that contains C6-sugar-containing oligomers, C6 sugar monomers, C5-sugar-containing oligomers, C5 sugar monomers, or any combination thereof is presented. The process includes the steps of reacting biomass or a biomass-derived reactant with a solvent system including a lactone and water, and an acid catalyst. The reaction yields a product mixture containing water-soluble C6-sugar-containing oligomers, C6-sugar monomers, C5-sugar-containing oligomers, C5-sugar monomers, or any combination thereof. A solute is added to the product mixture to cause partitioning of the product mixture into an aqueous layer containing the carbohydrates and a substantially immiscible organic layer containing the lactone.

  18. Determination of fat- and water-soluble vitamins by supercritical fluid chromatography: A review.

    Science.gov (United States)

    Tyśkiewicz, Katarzyna; Dębczak, Agnieszka; Gieysztor, Roman; Szymczak, Tomasz; Rój, Edward

    2018-01-01

    Vitamins are compounds that take part in all basic functions of an organism but also are subject of number of studies performed by different researchers. Two groups of vitamins are distinguished taking into consideration their solubility. Chromatography with supercritical CO 2 has found application in the determination, separation, and quantitative analyses of both fat- and water-soluble vitamins. The methods of vitamins separation have developed and improved throughout the years. Both groups of compounds were separated using supercritical fluid chromatography with different detection on different stationary phases. The main aim of this review is to provide an overview of the studies of vitamins separation that have been determined so far. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Microwave-induced facile synthesis of water-soluble fluorogenic alginic acid derivatives.

    Science.gov (United States)

    Chhatbar, Mahesh U; Meena, Ramavatar; Prasad, Kamalesh; Chejara, Dharmesh R; Siddhanta, A K

    2011-04-01

    A facile microwave-induced method was developed for synthesizing water-soluble fluorescent derivatives of alginic acid (ALG) with four different diamines, hydrazine (HY), ethylenediamine (EDA), 1,6-hexanediamine (HDA), and 1,4-cyclohexanediamine (CHDA), followed by a cross-linking reaction with a natural cross linker genipin. The ethylenediamine derivative of alginic acid (ALG-EDA) exhibited good fluorescent activity, which upon cross linking was enhanced threefold. The other amide derivatives, for example, ALG-HY, ALG-HDA, and ALG-CHDA, were not fluorescent, but their respective crosslinked products exhibited excellent fluorescent activity. The fluorescence intensity had an inverse correlation with the number of carbon atoms present in the amine, which in turn was a function of degree of substitution (DS). These fluorescent polysaccharide derivatives are of potential utility in the domain of sensor applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Lumbar myelography using water-soluble contrast media. Lumbale Myelographie mit wasserloelichen Kontrastmitteln. Lehrbuch und Atlas

    Energy Technology Data Exchange (ETDEWEB)

    Langlotz, M

    1981-01-01

    With the new water-soluble contrast media developed in the last 10 years, lumbar myelography has become a simple and low-risk diagnostic method of great value which is hardly ever omitted before surgery is undertaken. The book attempts a synopsis of radiology and clinical examinations. In its first part, the pathological, clinical, and radiological aspects of diseases of the lumbosacral spinal duct are reviewed. The second part contains more than 300 myelographic pictures in original size. Each of the myelograms is supplemented by the case history of the patient (anamnesis, neurological examination, therapy and course). Interpretation is facilitated by drawings at the beginning of each chapter which show the major pathological and radiological changes.

  1. Chemical Characteristics and Antioxidant Properties of Crude Water Soluble Polysaccharides from Four Common Edible Mushrooms

    Directory of Open Access Journals (Sweden)

    Pei-Long Sun

    2012-04-01

    Full Text Available Four crude water soluble polysaccharides, CABP, CAAP, CFVP and CLDP, were isolated from common edible mushrooms, including Agaricus bisporus, Auricularia auricula, Flammulina velutipes and Lentinus edodes, and their chemical characteristics and antioxidant properties were determined. Fourier Transform-infrared analysis showed that the four crude polysaccharides were all composed of β-glycoside linkages. The major monosaccharide compositions were D-galactose, D-glucose and D-mannose for CABP, CAAP and CLDP, while CFVP was found to consist of L-arabinose, D-galactose, D-glucose and D-mannose. The main molecular weight distributions of CABP and the other three polysaccharides were 66.0 × 104 Da, respectively. Antioxidant properties of the four polysaccharides were evaluated in in vitro systems and CABP showed the best antioxidant properties. The studied mushroom species could potentially be used in part of well-balanced diets and as a source of antioxidant compounds.

  2. Luminescent, water-soluble silicon quantum dots via micro-plasma surface treatment

    International Nuclear Information System (INIS)

    Wu, Jeslin J; Siva Santosh Kumar Kondeti, Vighneswara; Bruggeman, Peter J; Kortshagen, Uwe R

    2016-01-01

    Silicon quantum dots (SiQDs), with their broad absorption, narrow and size-tunable emission, and potential biocompatibility are highly attractive materials in biological imaging applications. The inherent hydrophobicity and instability of hydrogen-terminated SiQDs are obstacles to their widespread implementation. In this work, we successfully produced highly luminescent, hydrophilic SiQDs with long-term stability in water using non-thermal plasma techniques. Hydrogen-terminated SiQDs were produced in a low-pressure plasma and subsequently treated in water using an atmospheric-pressure plasma jet for surface modification. Preliminary assessments of the chemical mechanism(s) involved in the creation of water-soluble SiQDs were performed using Fenton’s reaction and various plasma chemistries, suggesting both OH and O species play a key role in the oxidation of the SiQDs. (letter)

  3. Radiation crosslinking of starch/water-soluble polymer blends for hydrogel

    Energy Technology Data Exchange (ETDEWEB)

    Hashim, K.; Mohid, N.; Bahari, K.; Dahlan, K.Z. [Radiation Processing Technology Division, Malaysian Institute Nuclear Technology Research Malaysia (MINT), Bangi, 43000 Kajang (Malaysia)

    2000-03-01

    Water-soluble polymers such as PVP(polyvinyl pyrrolidone) and PVA(polyvinyl alcohol), in aqueous solution can form hydrogel easily upon gamma or electron beam irradiation. The properties of hydrogels, particularly for wound dressing application, can be further improved by adding sago starch to the blend. Results show improved gel strength and elongation properties of the hydrogel with increasing sago concentration. It was found that the PVA/sago hydrogel gives better gel strength and elongation than the PVP/sago hydrogel. The tackiness property of the PVA/sago hydrogel increased with increase amount of sago starch added. In case of PVP/sago hydrogel, the tackiness property shows significant increase with increasing amount of sago except for the 5%PVP composition. The swelling properties of PVP/sago and PVA/sago hydrogel decreased with increasing amount of sago but the crosslink density of the hydrogels also reduced. (author)

  4. Sizes of water-soluble luminescent quantum dots measured by fluorescence correlation spectroscopy

    International Nuclear Information System (INIS)

    Zhang Pudun; Li Liang; Dong Chaoqing; Qian Huifeng; Ren Jicun

    2005-01-01

    In this paper, fluorescence correlation spectroscopy (FCS) was applied to measure the size of water-soluble quantum dots (QDs). The measurements were performed on a home-built FCS system based on the Stokes-Einstein equation. The obtained results showed that for bare CdTe QDs the sizes from FCS were larger than the ones from transmission electron microscopy (TEM). The brightness of QDs was also evaluated using FCS technique. It was found that the stability of the surface chemistry of QDs would be significantly improved by capping it with hard-core shell. Our data demonstrated that FCS is a simple, fast, and effective method for characterizing the fluorescent quantum dots, and is especially suitable for determining the fluorescent nanoparticles less than 10 nm in water solution

  5. Studies on water soluble polysaccharides from Pithecellobium dulce (Roxb.) Benth. seeds.

    Science.gov (United States)

    Bagchi, S; Kumar, K Jayaram

    2016-03-15

    In this existing experimental work, water soluble PDP polysaccharides were secluded from Pithecellobium dulce (Roxb.) Benth. seeds. The physicochemical properties were analyzed in terms of swelling power, solubility, pH and water holding capacity. Micromeretic studies proved the polysaccharide may be used a potential pharmaceutical adjuvant. The polysaccharide was characterized by FT-IR, SEM, TGA and NMR techniques. Methylation analysis confirmed that the polysaccharide is composed of Arabinose (Araf) units. The chemical shifts of anomeric proton region were found in the region of 4.4-5.5ppm. Thermogravimetric analysis showed that PDP polysaccharide was thermally stable. The in vitro antioxidant capacities of the polysaccharide were investigated in terms of scavenging of hydroxyl radicals, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radicals, hydrogen peroxide (H2O2) and reducing power assay. The polysaccharide fractions showed activity in a concentration dependent manner which was comparable to the standard, ascorbic acid. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Paraquat induces oxidative stress and neuronal cell death; neuroprotection by water-soluble Coenzyme Q10

    International Nuclear Information System (INIS)

    McCarthy, S.; Somayajulu, M.; Sikorska, M.; Borowy-Borowski, H.; Pandey, S.

    2004-01-01

    Neuronal cell death induced by oxidative stress is correlated with numerous neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and stroke. The causes of sporadic forms of age-related neurodegenerative diseases are still unknown. Recently, a correlation between paraquat exposure and neurodegenerative diseases has been observed. Paraquat, a nonselective herbicide, was once widely used in North America and is still routinely used in Taiwan. We have used differentiated Human Neuroblastoma (SHSY-5Y) cells as an in vitro model to study the mechanism of cell death induced by paraquat. We observed that paraquat-induced oxidative stress in differentiated SHSY-5Y cells as indicated by an increase in the production of cellular reactive oxygen species (ROS). Furthermore, apoptosis was evident as indicated by cellular and nuclear morphology and DNA fragmentation. Interestingly, pretreatment of SHSY-5Y cells with water-soluble Coenzyme Q 10 (CoQ 10 ) before paraquat exposure inhibited ROS generation. Pretreatment with CoQ 10 also significantly reduced the number of apoptotic cells and DNA fragmentation. We also analyzed the effect of paraquat and CoQ 10 on isolated mitochondria. Our results indicated that treatment with paraquat induced the generation of ROS from isolated mitochondria and depolarization of the inner mitochondrial membrane. Pretreatment with CoQ 10 was able to inhibit ROS generation from isolated mitochondria as well as the collapse of mitochondrial membrane potential. Our results indicate that water-soluble CoQ 10 can prevent oxidative stress and neuronal damage induced by paraquat and therefore, can be used for the prevention and therapy of neurodegenerative diseases caused by environmental toxins

  7. Fast dissolution of poorly water soluble drugs from fluidized bed coated nanocomposites: Impact of carrier size.

    Science.gov (United States)

    Azad, Mohammad; Moreno, Jacqueline; Bilgili, Ecevit; Davé, Rajesh

    2016-11-20

    Formation of core-shell nanocomposites of Fenofibrate and Itraconazole, model poorly water soluble drugs, via fluidized bed (FB) coating of their well-stabilized high drug loaded nanosuspensions is investigated. Specifically, the extent of dissolution enhancement, when fine carrier particles (sub-50μm) as opposed to the traditional large carrier particles (>300μm) are used, is examined. This allows testing the hypothesis that greatly increased carrier surface area and more importantly, thinner shell for finer carriers at the same drug loading can significantly increase the dissolution rate when spray-coated nanosuspensions are well-stabilized. Fine sub-50μm lactose (GranuLac ® 200) carrier particles were made fluidizable via dry coating with nano-silica, enabling decreased cohesion, fluidization and subsequent nanosuspension coating. For both drugs, 30% drug loaded suspensions were prepared via wet-stirred media milling using hydroxypropyl methyl cellulose and sodium dodecyl sulfate as stabilizers. The stabilizer concentrations were varied to affect the milled particle size and prepare a stable nanosuspension. The suspensions were FB coated onto hydrophilic nano-silica (M-5P) dry coated sub-50μm lactose (GranuLac ® 200) carrier particles or larger carrier particles of median size >300μm (PrismaLac ® 40). The resulting finer composite powders (sub-100μm) based on GranuLac ® 200 were freely flowing, had high bulk density, and had much faster, immediate dissolution of the poorly water-soluble drugs, in particular for Itraconazole. This is attributed to a much higher specific surface area of the carrier and corresponding thinner coating layer for fine carriers as opposed to those for large carrier particles. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Water-soluble chelating polymers for removal of actinides from wastewater

    International Nuclear Information System (INIS)

    Jarvinen, G.D.

    1997-01-01

    Polymer filtration is a technology under development to selectively recover valuable or regulated metal ions from process or wastewaters. The technology uses water-soluble chelating polymers that are designed to selectively bind with metal ions in aqueous solutions. The polymers have a sufficiently large molecular weight that they can be separated and concentrated using available ultrafiltration (UF) technology. The UF range is generally considered to include molecular weights from about 3000 to several million daltons and particles sizes of about 2 to 1000 nm. Water and smaller unbound components of the solution pass freely through the UF membrane. The polymers can then be reused by changing the solution conditions to release the metal ions that are recovered in concentrated form for recycle or disposal. Some of the advantages of polymer filtration relative to technology now in use are rapid binding kinetics, high selectivity, low energy and capital costs, and a small equipment footprint. Some potential commercial applications include electroplating rinse waters, photographic processing, nuclear power plant cooling water; remediation of contaminated soils and groundwater; removal of mercury contamination; and textile, paint and dye production. The purpose of this project is to evaluate this technology to remove plutonium, americium, and other regulated metal ions from various process and waste streams found in nuclear facilities. The work involves preparation of the water-soluble chelating polymers; small-scale testing of the chelating polymer systems for the required solubility, UF properties, selectivity and binding constants; followed by an engineering assessment at a larger scale to allow comparison to competing separation technologies. This project focuses on metal-ion contaminants in waste streams at the Plutonium Facility and the Waste Treatment Facility at LANL. Potential applications at other DOE facilities are also apparent

  9. A novel water soluble solvatochromic probe as a micropolarity reporter for homogeneous and microheterogeneous media

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Amrita; Kedia, Niraja [Department of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur Campus, BCKV Main P.O., Mohanpur 741252, Nadia, WB (India); Bagchi, Sanjib, E-mail: bsanjibb@yahoo.com [Department of Chemistry and Biochemistry, Presidency University, 86/1 College Street, Kolkata 700073 (India)

    2014-07-01

    A new water soluble donor–acceptor dye, sodium 4-(methyl((1E,3E)-3-(1-oxo-1H-inden-2(3H)-ylidene)prop-1-enyl)amino) benzoate (DN3) has been synthesized. Optical response of the solvatochromic dye (DN3) has been studied in various homogeneous (neat and mixed binary solvents) and heterogeneous (SDS and CTAB homomicelle and β-cyclodextrin nanocavity) media. To get information regarding the change in the solvation interaction of the dye with the alteration in its microenvironment in different media, the photophysical properties of the dye have been monitored in various media using steady state and time resolved spectral analysis. Results obtained for mixed binary solvents containing water indicate that the solute is preferentially solvated by one of the component solvents and solvent–solvent interactions are also important in determining the preference. Effect of variation of pH in aqueous medium on the spectroscopic parameters of the dye has been studied and its pKa has been estimated. Studies in homomicelles (SDS and CTAB) reveal that the dye distributes itself between the aqueous and the micellar phase and the values of distribution coefficient have been estimated from the fluorescence parameters. The dye is encapsulated in β-cyclodextrin nanocavity and a 1:2 dye-β-cyclodextrin host–guest interaction is indicated. Semi-empirical quantum chemical calculations have been carried out to support the experimental results. - Highlights: • A water soluble fluorescent dye has been synthesized and studied in various media. • The dye is sensitive towards changes in micropolarity and pH of the medium. • Study in mixed binary solvent system indicates preferential solvation of the dye. • Stronger interaction of the dye is indicated with CTAB micelles compared to SDS. • Study in aqueous β-CD medium reveals favorable 1:2 binding of the dye with β-CD.

  10. Water-soluble chelating polymers for removal of actinides from wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Jarvinen, G.D. [Los Alamos National Lab., NM (United States)

    1997-10-01

    Polymer filtration is a technology under development to selectively recover valuable or regulated metal ions from process or wastewaters. The technology uses water-soluble chelating polymers that are designed to selectively bind with metal ions in aqueous solutions. The polymers have a sufficiently large molecular weight that they can be separated and concentrated using available ultrafiltration (UF) technology. The UF range is generally considered to include molecular weights from about 3000 to several million daltons and particles sizes of about 2 to 1000 nm. Water and smaller unbound components of the solution pass freely through the UF membrane. The polymers can then be reused by changing the solution conditions to release the metal ions that are recovered in concentrated form for recycle or disposal. Some of the advantages of polymer filtration relative to technology now in use are rapid binding kinetics, high selectivity, low energy and capital costs, and a small equipment footprint. Some potential commercial applications include electroplating rinse waters, photographic processing, nuclear power plant cooling water; remediation of contaminated soils and groundwater; removal of mercury contamination; and textile, paint and dye production. The purpose of this project is to evaluate this technology to remove plutonium, americium, and other regulated metal ions from various process and waste streams found in nuclear facilities. The work involves preparation of the water-soluble chelating polymers; small-scale testing of the chelating polymer systems for the required solubility, UF properties, selectivity and binding constants; followed by an engineering assessment at a larger scale to allow comparison to competing separation technologies. This project focuses on metal-ion contaminants in waste streams at the Plutonium Facility and the Waste Treatment Facility at LANL. Potential applications at other DOE facilities are also apparent.

  11. Evaluation of Poly(2-Ethyl-2-Oxazoline) Containing Copolymer Networks of Varied Composition as Sustained Metoprolol Tartrate Delivery Systems

    OpenAIRE

    Kostova, Bistra; Ivanova, Sijka; Balashev, Konstantin; Rachev, Dimitar; Christova, Darinka

    2014-01-01

    Segmented copolymer networks (SCN) based on poly(2-ethyl-2-oxazoline) and containing 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, and/or methyl methacrylate segments have been evaluated as potential sustained release systems of the water soluble cardioselective β-blocker metoprolol tartrate. The structure and properties of the drug carriers were investigated by differential scanning calorimetry, attenuated total reflectance Fourier transform infrared spectroscopy, scanning electron ...

  12. The elevation effect on water-soluble polysaccharides and DPPH free radical scavenging activity of Ganoderma lucidum K

    Science.gov (United States)

    Darsih, C.; Apriyana, W.; Nur Hayati, S.; Taufika Rosyida, V.; Hernawan; Dewi Poeloengasih, C.

    2017-02-01

    Water soluble polysaccharide is one of the important phytochemical in Ganoderma lucidum K. Phytochemicals in the plants, microorganisms, and plants were affected by internal and external factors. The objective of the research was to evaluate the effect of elevation on the water-soluble polysaccharides and its DPPH radical scavenging activity. We found that the water-polysaccharides in mushroom from Godean (elevation Ganoderma lucidum K from Godean (IC50 11.5 ± 0.29 mg/mL) higher than Kaliurang (IC50 14.4 ± 0.27%).

  13. Accelerated healing of cutaneous leishmaniasis in non-healing BALB/c mice using water soluble amphotericin B-polymethacrylic acid.

    Science.gov (United States)

    Corware, Karina; Harris, Debra; Teo, Ian; Rogers, Matthew; Naresh, Kikkeri; Müller, Ingrid; Shaunak, Sunil

    2011-11-01

    Cutaneous leishmaniasis (CL) is a neglected tropical disease that causes prominent skin scaring. No water soluble, non-toxic, short course and low cost treatment exists. We developed a new water soluble amphotericin B-polymethacrylic acid (AmB-PMA) using established and scalable chemistries. AmB-PMA was stable for 9 months during storage. In vitro, it was effective against Leishmania spp. promastigotes and amastigote infected macrophages. It was also less toxic and more effective than deoxycholate-AmB, and similar to liposomal AmB. Its in vivo activity was determined in both early and established CL lesion models of Leishmania major infection in genetically susceptible non-healing BALB/c mice. Intradermal AmB-PMA at a total dose of 18 mg of AmB/kg body weight led to rapid parasite killing and lesion healing. No toxicity was seen. No parasite relapse occurred after 80 days follow-up. Histological studies confirmed rapid parasite clearance from macrophages followed by accelerated fibroblast mediated tissue repair, regeneration and cure of the infection. Quantitative mRNA studies of the CL lesions showed that accelerated healing was associated with increased Tumour Necrosis Factor-α and Interferon-γ, and reduced Interleukin-10. These results suggest that a cost-effective AmB-PMA could be used to pharmacologically treat and immuno-therapeutically accelerate the healing of CL lesions. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Design of an expert system for the development and formulation of push-pull osmotic pump tablets containing poorly water-soluble drugs.

    Science.gov (United States)

    Zhang, Zhi-hong; Dong, Hong-ye; Peng, Bo; Liu, Hong-fei; Li, Chun-lei; Liang, Min; Pan, Wei-san

    2011-05-30

    The purpose of this article was to build an expert system for the development and formulation of push-pull osmotic pump tablets (PPOP). Hundreds of PPOP formulations were studied according to different poorly water-soluble drugs and pharmaceutical acceptable excipients. The knowledge base including database and rule base was built based on the reported results of hundreds of PPOP formulations containing different poorly water-soluble drugs and pharmaceutical excipients and the experiences available from other researchers. The prediction model of release behavior was built using back propagation (BP) neural network, which is good at nonlinear mapping and learning function. Formulation design model was established based on the prediction model of release behavior, which was the nucleus of the inference engine. Finally, the expert system program was constructed by VB.NET associating with SQL Server. Expert system is one of the most popular aspects in artificial intelligence. To date there is no expert system available for the formulation of controlled release dosage forms yet. Moreover, osmotic pump technology (OPT) is gradually getting consummate all over the world. It is meaningful to apply expert system on OPT. Famotidine, a water insoluble drug was chosen as the model drug to validate the applicability of the developed expert system. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Thermodynamics of Highly Supersaturated Aqueous Solutions of Poorly Water-Soluble Drugs-Impact of a Second Drug on the Solution Phase Behavior and Implications for Combination Products.

    Science.gov (United States)

    Trasi, Niraj S; Taylor, Lynne S

    2015-08-01

    There is increasing interest in formulating combination products that contain two or more drugs. Furthermore, it is also common for different drug products to be taken simultaneously. This raises the possibility of interactions between different drugs that may impact formulation performance. For poorly water-soluble compounds, the supersaturation behavior may be a critical factor in determining the extent of oral absorption. The goal of the current study was to evaluate the maximum achievable supersaturation for several poorly water-soluble compounds alone, and in combination. Model compounds included ritonavir, lopinavir, paclitaxel, felodipine, and diclofenac. The "amorphous solubility" for the pure drugs was determined using different techniques and the change in this solubility was then measured in the presence of differing amounts of a second drug. The results showed that "amorphous solubility" of each component in aqueous solution is substantially decreased by the second component, as long as the two drugs are miscible in the amorphous state. A simple thermodynamic model could be used to predict the changes in solubility as a function of composition. This information is of great value when developing co-amorphous or other supersaturating formulations and should contribute to a broader understanding of drug-drug physicochemical interactions in in vitro assays as well as in the gastrointestinal tract. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  16. Water-soluble light-emitting nanoparticles prepared by non-covalent bond self-assembly of a hydroxyl group functionalized oligo(p-phenyleneethynylene) with different water-soluble polymers

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Water-soluble light-emitting nanoparticles were prepared from hydroxyl group functionalized oligos(p-phenyleneethynylene) (OHOPEL) and water-soluble polymers(PEG,PAA,and PG) by non-covalent bond self-assembly.Their structure and optoelectronic properties were investigated through dynamic light scattering(DLS) ,UV and PL spectroscopy.The optical properties of OHOPEL-based water-soluble nanoparticles exhibited the same properties as that found in OHOPEL films,indicating the existence of interchain-aggregation of OHOPELs in the nanoparticles.OHOPEL-based nanoparticles prepared from conjugated oligomers show smaller size and lower dispersity than nanoparticles from conjugated polymers,which means that the structures of water-soluble nanoparticles are linked to the conjugated length.Furthermore,the OHOPEL/PG and OHOPEL/PAA systems produced smaller particles and lower polydispersity than the OHOPEL/PEG system,indicating that there may exist influence of the strength of non-covalent bonds on the size and degree of dispersity of the nanoparticles.

  17. In vitro and in vivo evaluation of docetaxel-loaded stearic acid-modified Bletilla striata polysaccharide copolymer micelles.

    Directory of Open Access Journals (Sweden)

    Qingxiang Guan

    Full Text Available Bletilla striata polysaccharides (BSPs have been used in pharmaceutical and biomedical industry, the aim of the present study was to explore a BSPs amphiphilic derivative to overcome its application limit as poorly water-soluble drug carriers due to water-soluble polymers. Stearic acid (SA was selected as a hydrophobic block to modify B. striata polysaccharides (SA-BSPs. Docetaxel (DTX-loaded SA-BSPs (DTX-SA-BSPs copolymer micelles were prepared and characterized. The DTX release percentage in vitro and DTX concentration in vivo was carried out by using high performance liquid chromatography. HepG2 and HeLa cells were subjected to MTT (3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyl tetrazonium bromide assay to evaluate the cell viability. In vitro evaluation of copolymer micelles showed higher drug encapsulation and loading capacity. The release percentage of DTX from DTX-SA-BSPs copolymer micelles and docetaxel injection was 66.93 ± 1.79% and 97.06 ± 1.56% in 2 days, respectively. The DTX-SA-BSPs copolymer micelles exhibited a sustained release of DTX. A 50% increase in growth inhibition was observed for HepG2 cells treated with DTX-SA-BSPs copolymer micelles as compared to those treated with docetaxel injection for 72 h. DTX-SA-BSPs copolymer micelles presented a similar growth inhibition effect on Hela cells. Furthermore, absolute bioavailability of DTX-SA-BSPs copolymer micelles was shown to be 1.39-fold higher than that of docetaxel injection. Therefore, SA-BSPs copolymer micelles may be used as potential biocompatible polymers for cancer chemotherapy.

  18. Synthesis and characterization of PEPO grafted carboxymethyl guar and carboxymethyl tamarind as new thermo-associating polymers.

    Science.gov (United States)

    Gupta, Nivika R; Torris A T, Arun; Wadgaonkar, Prakash P; Rajamohanan, P R; Ducouret, Guylaine; Hourdet, Dominique; Creton, Costantino; Badiger, Manohar V

    2015-03-06

    New thermo associating polymers were designed and synthesized by grafting amino terminated poly(ethylene oxide-co-propylene oxide) (PEPO) onto carboxymethyl guar (CMG) and carboxymethyl tamarind (CMT). The grafting was performed by coupling reaction between NH2 groups of PEPO and COOH groups of CMG and CMT using water-soluble EDC/NHS as coupling agents. The grafting efficiency and the temperature of thermo-association, T(assoc) in the copolymer were studied by NMR spectroscopy. The graft copolymers, CMG-g-PEPO and CMT-g-PEPO exhibited interesting thermo-associating behavior which was evidenced by the detailed rheological and fluorescence measurements. The visco-elastic properties (storage modulus, G'; loss modulus, G") of the copolymer solutions were investigated using oscillatory shear experiments. The influence of salt and surfactant on the T(assoc) was also studied by rheology, where the phenomenon of "Salting out" and "Salting in" was observed for salt and surfactant, respectively, which can give an easy access to tunable properties of these copolymers. These thermo-associating polymers with biodegradable nature of CMG and CMT can have potential applications as smart injectables in controlled release technology and as thickeners in cosmetics and pharmaceutical formulations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Outcomes of asymptomatic anastomotic leaks found on routine postoperative water-soluble enema following anterior resection for cancer.

    Science.gov (United States)

    Killeen, S; Souroullas, P; Ho Tin, H; Hunter, I A; O'Grady, H; Gunn, J; Hartley, J E

    2013-11-01

    The incidence and consequence of an anastomotic leak associated with low anterior resection for cancer mandates covering stoma in most cases. A water-soluble enema is often performed to assess anastomotic integrity prior to stoma reversal. The functional outcome following reversal in patients with occult radiologically detected leaks is poorly defined. The goal of the present study was to determine the functional outcome in patients with a radiologically detected anastomotic leak who subsequently underwent stoma reversal. This case control study used patients with and without radiologically detected occult anastomotic leak having undergone reversal of covering stomata. The study group was matched with controls for age, gender, procedure, tumor stage, and adjuvant/neoadjuvant therapy. Validated fecal incontinence quality of life (FIQL), Cleveland Clinic Fecal Incontinence Score (CCFIS), and the Memorial Sloan-Kettering Cancer Center (MSKCC) Bowel Function Index (BFI) were used. Patient satisfaction, medication use, and ancillary procedures prior to closure were also recorded. Thirteen patients with radiologically detected occult anastomotic leaks and 13 matched controls were identified from a prospectively maintained database. The FIQL, CCFIS, and MSKCC BFI scores were significantly reduced in those with occult leaks. The mean number of radiological and surgical interventions was significantly greater in the patients with occult leaks. Antidiarrheal and bulking agent use, as well as patient satisfaction, were the same for both groups. Only one patient in the occult leak group would not undergo stoma reversal again. Reversal of a defunctioning ileostomy in the presence of an occult radiological leak can be associated with poorer functional outcomes, but patient satisfaction is undiminished.

  20. Synthesis and evaluation of water-soluble poly(vinyl alcohol)-paclitaxel conjugate as a macromolecular prodrug

    International Nuclear Information System (INIS)

    Kakinoki, Atsufumi; Kaneo, Yoshiharu; Tanaka, Tetsuro; Hosokawa, Yoshitsugu

    2008-01-01

    Paclitaxel (PTX) is an antitumor agent for the treatment of various human cancers. Cremophor EL and ethanol are used to formulate PTX in commercial injection solutions, because of its poor solubility in water. However, these agents cause severe allergic reaction upon intravenous administration. The aim of this study is to synthesize water-soluble macromolecular prodrugs of PTX for enhancing the therapeutic efficacy. Poly (vinyl alcohol) (PVA, 80 kDa), water-soluble synthetic polymer, was used as a drug carrier which is safe and stable in the body. The 2'-hydroxyl group of PTX was reacted with succinic anhydride and then carboxylic group of the succinyl spacer was coupled to PVA via ethylene diamine spacer, resulting the water-soluble prodrug of poly (vinyl alcohol)-paclitaxel conjugate (PVA-SPTX). The solubility of PTX was greatly enhanced by the conjugation to PVA. The release of PTX from the conjugate was accelerated at the neutral to basic conditions in in vitro release experiment. [ 125 I]-labeled PVA-SPTX was retained in the blood circulation for several days and was gradually distributed into the tumorous tissue after intravenous injection to the tumor-bearing mice. PVA-SPTX inhibited the growth of sarcoma 180 cells subcutaneously inoculated in mice. It was suggested that the water-solubility of PTX was markedly enhanced by the conjugation to PVA, and PVA-SPTX effectively delivered PTX to the tumorous tissue due to the enhanced permeability and retention (EPR) effect. (author)

  1. Water-soluble carbohydrates and in vitro digestibility of annual ryegrass (Lolium ridigum Gaudin) sown at varying densities

    NARCIS (Netherlands)

    Smouter, H.; Simpson, R.J.; Pear, G.R.

    1995-01-01

    An experiment is described in which the tiller density of microswards of Lolium rigidum was varied by altering planting density. The treatments were expected to alter the interplant competition for light and thus affect the concentration of water-soluble carbohydrates (WSC) of the grass swards.

  2. Cultivar by environment effects of perennial ryegrass cultivars selected for high water soluble carbohydrates managed under differing precipitation levels

    Science.gov (United States)

    Historic results of perennial ryegrass (Lolium perenne L.) breeding include improved disease resistance, biomass, and nutritional quality. Yet, lack of tolerance to water stress limits its wise use. Recent efforts to increase water soluble carbohydrate (WSC) content in perennial ryegrass may incre...

  3. Selection of an empirical detection method for determination of water-soluble carbohydrates in feedstuffs for application in ruminant nutrition

    Science.gov (United States)

    Water-soluble carbohydrates (WSC) are commonly measured in ruminant feedstuffs for use in diet formulation. However, we lack information as to which empirical detection assay most correctly measures WSC. The objective of this study was to determine which commonly used empirical assay was most approp...

  4. NMR Structure and Action on Nicotinic Acetylcholine Receptors of Water-soluble Domain of Human LYNX1

    Czech Academy of Sciences Publication Activity Database

    Lyukmanova, E. N.; Shenkarev, Z. O.; Shulepko, M. A.; Mineev, K. S.; D´Hoedt, D.; Kasheverov, I. E.; Filkin, S. Yu.; Krivolapova, A. P.; Janíčková, Helena; Doležal, Vladimír; Dolgikh, D. A.; Arseniev, A. S.; Bertrand, D.; Tsetlin, V.I.; Kirpichnikov, M. P.

    2011-01-01

    Roč. 286, č. 12 (2011), s. 10618-10627 ISSN 0021-9258 R&D Projects: GA ČR(CZ) GA305/09/0681 Institutional research plan: CEZ:AV0Z50110509 Keywords : NMR structure * nicotinic acetylcholine receptor * water-soluble domain Subject RIV: FH - Neurology Impact factor: 4.773, year: 2011

  5. One-pot synthesis of water soluble iron nanoparticles using rationally-designed peptides and ligand release.

    Science.gov (United States)

    Papst, Stefanie; Cheong, Soshan; Banholzer, Moritz J; Brimble, Margaret A; Williams, David E; Tilley, Richard D

    2013-05-18

    Herein we report the rational design of new phosphopeptides for control of nucleation, growth and aggregation of water-soluble, superparamagnetic iron-iron oxide core-shell nanoparticles. The use of the designed peptides enables a one-pot synthesis that avoids utilizing unstable or toxic iron precursors, organic solvents, and the need for exchange of capping agent after synthesis of the NPs.

  6. [Fast separation and analysis of water-soluble vitamins in spinach by capillary electrophoresis with high voltage].

    Science.gov (United States)

    Hu, Xiaoqin; You, Huiyan

    2009-11-01

    In capillary electrophoresis, 0-40 kV (even higher) voltage can be reached by a connecting double-model high voltage power supply. In the article, water-soluble vitamins, VB1, VB2, VB6, VC, calcium D-pantothenate, D-biotin, nicotinic acid and folic acid in vegetable, were separated by using the high voltage power supply under the condition of electrolyte water solution as running buffer. The separation conditions, such as voltage, the concentration of buffer and pH value etc. , were optimized during the experiments. The results showed that eight water-soluble vitamins could be baseline separated in 2.2 min at 40 kV applied voltage, 25 mmol/L sodium tetraborate buffer solution (pH 8.8). The water-soluble vitamins in spinach were quantified and the results were satisfied. The linear correlation coefficients of the water-soluble vitamins ranged from 0.9981 to 0.9999. The detection limits ranged from 0.2 to 0.3 mg/L. The average recoveries ranged from 88.0% to 100.6% with the relative standard deviations (RSD) range of 1.15%-4.13% for the spinach samples.

  7. Anthropogenic Influence on Secondary Aerosol Formation and Total Water-Soluble Carbon on Atmospheric Particles

    Science.gov (United States)

    Gioda, Adriana; Mateus, Vinicius; Monteiro, Isabela; Taira, Fabio; Esteves, Veronica; Saint'Pierre, Tatiana

    2013-04-01

    On a global scale, the atmosphere is an important source of nutrients, as well as pollutants, because of its interfaces with soil and water. Important compounds in the gaseous phase are in both organic and inorganic forms, such as organic acids, nitrogen, sulfur and chloride. In spite of the species in gas form, a huge number of process, anthropogenic and natural, are able to form aerosols, which may be transported over long distances. Sulfates e nitrates are responsible for rain acidity; they may also increase the solubility of organic compounds and metals making them more bioavailable, and also can act as cloud condensation nuclei (CCN). Aerosol samples (PM2.5) were collected in a rural and industrial area in Rio de Janeiro, Brazil, in order to quantify chemical species and evaluate anthropogenic influences in secondary aerosol formation and organic compounds. Samples were collected during 24 h every six days using a high-volume sampler from August 2010 to July 2011. The aerosol mass was determined by Gravimetry. The water-soluble ionic composition (WSIC) was obtained by Ion Chromatography in order to determine the major anions (NO3-, SO4= and Cl-); total water-soluble carbon (TWSC) was determined by a TOC analyzer. The average aerosol (PM2.5) concentrations ranged from 1 to 43 ug/m3 in the industrial site and from 4 to 35 ug/m3 in the rural area. Regarding anions, the highest concentrations were measured for SO42- (10.6 μg/m3-12.6 μg/m3); where the lowest value was found in the rural site and the highest in the industrial. The concentrations for NO3- and Cl- ranged from 4.2 μg/m3 to 9.3 μg/m3 and 3.1 μg/m3 to 6.4 μg /m3, respectively. Sulfate was the major species and, like nitrate, it is related to photooxidation in the atmosphere. Interestingly sulfate concentrations were higher during the dry period and could be related to photochemistry activity. The correlations between nitrate and non-sea-salt sulfate were weak, suggesting different sources for these

  8. Novel electrosprayed nanospherules for enhanced aqueous solubility and oral bioavailability of poorly water-soluble fenofibrate

    Directory of Open Access Journals (Sweden)

    Yousaf AM

    2016-01-01

    Full Text Available Abid Mehmood Yousaf,1,2 Omer Mustapha,1 Dong Wuk Kim,1 Dong Shik Kim,1 Kyeong Soo Kim,1 Sung Giu Jin,1 Chul Soon Yong,3 Yu Seok Youn,4 Yu-Kyoung Oh,5 Jong Oh Kim,3 Han-Gon Choi1 1College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Gyeonggi, South Korea; 2Faculty of Pharmacy, University of Central Punjab, Johar, Lahore, Pakistan; 3College of Pharmacy, Yeungnam University, Gyongsan, North Gyeongsang, 4School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi, 5College of Pharmacy, Seoul National University, Seoul, South Korea Purpose: The purpose of the present research was to develop a novel electrosprayed nanospherule providing the most optimized aqueous solubility and oral bioavailability for poorly water-soluble fenofibrate.Methods: Numerous fenofibrate-loaded electrosprayed nanospherules were prepared with polyvinylpyrrolidone (PVP and Labrafil® M 2125 as carriers using the electrospray technique, and the effect of the carriers on drug solubility and solvation was assessed. The solid state characterization of an optimized formulation was conducted by scanning electron microscopy, powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopic analyses. Oral bioavailability in rats was also evaluated for the formulation of an optimized nanospherule in comparison with free drug and a conventional fenofibrate-loaded solid dispersion.Results: All of the electrosprayed nanospherule formulations had remarkably enhanced aqueous solubility and dissolution compared with free drug. Moreover, Labrafil M 2125, a surfactant, had a positive influence on the solubility and dissolution of the drug in the electrosprayed nanospherule. Increases were observed as the PVP/drug ratio increased to 4:1, but higher ratios gave no significant increases. In particular, an electrosprayed nanospherule composed of fenofibrate, PVP, and Labrafil M 2125 at the weight ratio of 1

  9. Constructing aptamer anchored nanovesicles for enhanced tumor penetration and cellular uptake of water soluble chemotherapeutics.

    Science.gov (United States)

    Li, Xin; Zhu, Xiumei; Qiu, Liyan

    2016-04-15

    Polymersomes represent a promising pharmaceutical vehicle for the delivery of hydrophilic therapeutic agents. However, modification of polymersomes with molecules that confer targeting functions remains challenging because of the strict requirements regarding the weight fractions of the hydrophilic and hydrophobic block polymers. In this study, based on the compatibility between cholesterol and polymeric carriers, polymersomes self-assembled by amphiphilic graft polyphosphazenes were endowed with a targeting function by incorporating the cholesterol-linked aptamer through a simple dialysis method. The aqueous interior of the polymersomes was employed to encapsulate water-soluble doxorubicin hydrochloride. In vivo experiments in tumor-bearing mice showed that the aptamer-anchored vesicle targeted accumulation at the tumor site, favorable penetration through tumor tissue, and incremental endocytosis into tumor cells. Correspondingly, the aptamer-anchored vesicle decreased systemic toxicity and effectively suppressed the growth of subcutaneous MCF-7 xenografts. These findings suggested that vesicles modified with targeted groups via hydrophobic supermolecular interactions could provide a platform for selective delivery of hydrophilic drug. Polymersomes have represented a promising type of pharmaceutical vehicles due to their predominant physical properties. However, it is still a challenge to endow polymersomes with active target function because of strict requirements of the weight fractions of hydrophilic polymer block to hydrophobic one. In this research, by taking advantage of the supermolecular interactions between amphiphilic graft polyphosphazene and cholesterol which was linked to aptamer AS1411, we prepared a targeted functional polymersome (PEP-DOX·HCl-Ap) through a simple method with high loading of water soluble anti-cancer drug doxorubicin hydrochloride. The in vivo experiments in MCF-7 tumor-bearing mice demonstrated several advantages of PEP

  10. Water Solubility of Plutonium and Uranium Compounds and Residues at TA-55

    International Nuclear Information System (INIS)

    Reilly, Sean Douglas; Smith, Paul Herrick; Jarvinen, Gordon D.; Prochnow, David Adrian; Schulte, Louis D.; DeBurgomaster, Paul Christopher; Fife, Keith William; Rubin, Jim; Worl, Laura Ann

    2016-01-01

    Understanding the water solubility of plutonium and uranium compounds and residues at TA-55 is necessary to provide a technical basis for appropriate criticality safety, safety basis and accountability controls. Individual compound solubility was determined using published solubility data and solution thermodynamic modeling. Residue solubility was estimated using a combination of published technical reports and process knowledge of constituent compounds. The scope of materials considered includes all compounds and residues at TA-55 as of March 2016 that contain Pu-239 or U-235 where any single item in the facility has more than 500 g of nuclear material. This analysis indicates that the following materials are not appreciably soluble in water: plutonium dioxide (IDC=C21), plutonium phosphate (IDC=C66), plutonium tetrafluoride (IDC=C80), plutonium filter residue (IDC=R26), plutonium hydroxide precipitate (IDC=R41), plutonium DOR salt (IDC=R42), plutonium incinerator ash (IDC=R47), uranium carbide (IDC=C13), uranium dioxide (IDC=C21), U 3 O 8 (IDC=C88), and uranium filter residue (IDC=R26). This analysis also indicates that the following materials are soluble in water: plutonium chloride (IDC=C19) and uranium nitrate (IDC=C52). Equilibrium calculations suggest that PuOCl is water soluble under certain conditions, but some plutonium processing reports indicate that it is insoluble when present in electrorefining residues (R65). Plutonium molten salt extraction residues (IDC=R83) contain significant quantities of PuCl 3 , and are expected to be soluble in water. The solubility of the following plutonium residues is indeterminate due to conflicting reports, insufficient process knowledge or process-dependent composition: calcium salt (IDC=R09), electrorefining salt (IDC=R65), salt (IDC=R71), silica (IDC=R73) and sweepings/screenings (IDC=R78). Solution thermodynamic modeling also indicates that fire suppression water buffered with a commercially-available phosphate

  11. Characterization of the Water-Soluble Fraction of Woody Biomass Pyrolysis Oils

    Energy Technology Data Exchange (ETDEWEB)

    Stankovikj, Filip; McDonald, Armando G.; Helms, Gregory L.; Olarte, Mariefel V.; Garcia-Perez, Manuel

    2017-01-31

    This paper reports a study of the chemical composition of the water soluble (WS) fraction obtained by cold water precipitation of two commercial wood pyrolysis oils (BTG and Amaron). The fraction studied accounts for between 50.3 and 51.3 wt. % of the oils. With the most common analytical techniques used today for the characterization of this fraction (KF titration, GC/MS, hydrolysable sugars and total carbohydrates), it is possible to quantify only between 45 and 50 wt. % of it. Our results confirm that most of the total carbohydrates (hydrolysable sugars and non-hydrolysable) are soluble in water. The ion chromatography hydrolysis method showed that between 11.6 and 17.3 wt. % of these oils were hydrolysable sugars. A small quantity of phenols detectable by GC/MS (between 2.5 and 3.9 wt. %) were identified. It is postulated that the unknown high molecular weight fraction (30-55 wt. %) is formed by highly dehydrated sugars rich in carbonyl groups and WS phenols. The overall content of carbonyl, carboxyl, hydroxyl and phenolic compounds in the WS fraction were quantified by titration, Folin-Ciocalteu, 31P-NMR and 1H-NMR. The WS fraction contains between 5.5 and 6.2 mmol/g of carbonyl groups, between 0.4 and 1.0 mmol/g of carboxylic acid groups, between 1.2 and 1.8 mmol/g phenolic -OH, and between 6.0 and 7.9 mmol/g of aliphatic alcohol groups. Translation into weight fractions of the WS was done by supposing surrogate structures for the water soluble phenols, carbonyl and carboxyl groups and we estimated the content of WS phenols (21-27 wt. %), carbonyl (5-14 wt.%), and carboxyl (0-4 wt.%). Together with the total carbohydrates (23-27 wt.%), this approach leads to > 90 wt. % of the WS material in the bio-oils being quantified. We speculate the larger portion of the difference between the total carbohydrates and hydrolysable sugars is the missing furanic fraction. Further refinement of the suggested methods and development of separation schemes to obtain and

  12. Water Solubility of Plutonium and Uranium Compounds and Residues at TA-55

    Energy Technology Data Exchange (ETDEWEB)

    Reilly, Sean Douglas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Smith, Paul Herrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Jarvinen, Gordon D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Prochnow, David Adrian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Schulte, Louis D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; DeBurgomaster, Paul Christopher [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Fife, Keith William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Rubin, Jim [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Worl, Laura Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States

    2016-06-13

    Understanding the water solubility of plutonium and uranium compounds and residues at TA-55 is necessary to provide a technical basis for appropriate criticality safety, safety basis and accountability controls. Individual compound solubility was determined using published solubility data and solution thermodynamic modeling. Residue solubility was estimated using a combination of published technical reports and process knowledge of constituent compounds. The scope of materials considered includes all compounds and residues at TA-55 as of March 2016 that contain Pu-239 or U-235 where any single item in the facility has more than 500 g of nuclear material. This analysis indicates that the following materials are not appreciably soluble in water: plutonium dioxide (IDC=C21), plutonium phosphate (IDC=C66), plutonium tetrafluoride (IDC=C80), plutonium filter residue (IDC=R26), plutonium hydroxide precipitate (IDC=R41), plutonium DOR salt (IDC=R42), plutonium incinerator ash (IDC=R47), uranium carbide (IDC=C13), uranium dioxide (IDC=C21), U3O8 (IDC=C88), and uranium filter residue (IDC=R26). This analysis also indicates that the following materials are soluble in water: plutonium chloride (IDC=C19) and uranium nitrate (IDC=C52). Equilibrium calculations suggest that PuOCl is water soluble under certain conditions, but some plutonium processing reports indicate that it is insoluble when present in electrorefining residues (R65). Plutonium molten salt extraction residues (IDC=R83) contain significant quantities of PuCl3, and are expected to be soluble in water. The solubility of the following plutonium residues is indeterminate due to conflicting reports, insufficient process knowledge or process-dependent composition: calcium salt (IDC=R09), electrorefining salt (IDC=R65), salt (IDC=R71), silica (IDC=R73) and sweepings/screenings (IDC=R78). Solution thermodynamic modeling also indicates that fire suppression water buffered with a

  13. Exploitation of 3D face-centered cubic mesoporous silica as a carrier for a poorly water soluble drug: influence of pore size on release rate.

    Science.gov (United States)

    Zhu, Wenquan; Wan, Long; Zhang, Chen; Gao, Yikun; Zheng, Xin; Jiang, Tongying; Wang, Siling

    2014-01-01

    The purposes of the present work were to explore the potential application of 3D face-centered cubic mesoporous silica (FMS) with pore size of 16.0nm as a delivery system for poorly soluble drugs and investigate the effect of pore size on the dissolution rate. FMS with different pore sizes (16.0, 6.9 and 3.7nm) was successfully synthesized by using Pluronic block co-polymer F127 as a template and adjusting the reaction temperatures. Celecoxib (CEL), which is a BCS class II drug, was used as a model drug and loaded into FMS with different pore sizes by the solvent deposition method at a drug-silica ratio of 1:4. Characterization using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformation infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), nitrogen adsorption, X-ray diffraction (XRD), and differential scanning calorimetry (DSC) was used to systematically investigate the drug loading process. The results obtained showed that CEL was in a non-crystalline state after incorporation of CEL into the pores of FMS-15 with pore size of 16.0nm. In vitro dissolution was carried out to demonstrate the effects of FMS with different pore sizes on the release of CEL. The results obtained indicated that the dissolution rate of CEL from FMS-15 was significantly enhanced compared with pure CEL. This could be explained by supposing that CEL encountered less diffusion resistance and its crystallinity decreased due to the large pore size of 16.0nm and the nanopore channels of FMS-15. Moreover, drug loading and pore size both play an important role in enhancing the dissolution properties for the poorly water-soluble drugs. As the pore size between 3.7 and 16.0nm increased, the dissolution rate of CEL from FMS gradually increased. © 2013.

  14. Experimental density, viscosity, interfacial tension and water solubility of ethyl benzene-α-methyl benzyl alcohol–water system

    International Nuclear Information System (INIS)

    Barega, Esayas W.; Zondervan, Edwin; Haan, André B. de

    2013-01-01

    Highlights: • Properties were measured for MBA (methyl benzyl alcohol)-EB (ethyl benzene)-water. • MBA concentration was found to influence all the properties strongly. • The water solubility, density, and viscosity increased at high MBA concentration. • The interfacial tension decreased sharply at high MBA concentration. • MBA dictates the phase separation and mass transfer of the ternary system. -- Abstract: Density, viscosity, interfacial tension, and water solubility were measured for the (α-methyl benzyl alcohol (MBA) + Ethyl benzene (EB)) system at different concentrations of MBA in contact with water and sodium hydroxide solution (0.01 mol · kg −1 ) as aqueous phases. The properties were measured to identify the component which plays a governing role in changing the physical properties relevant to mass transfer and phase separation of the ternary system. The concentration of MBA was found to be the major factor influencing all the properties. The water solubility, the density, and the viscosity increased notably at higher concentrations of MBA; while, the interfacial tension decreased strongly. The use of 0.01 mol · kg −1 NaOH as an aqueous phase resulted in a decrease of the interfacial tension and a minor decrease in the water solubility. The density data were correlated using a quadratic mixing rule to describe the influence of concentration at any temperature. The viscosity data are correlated using the Nissan and Grunberg and Katti-Chaudhri equations. The Szyzkowski’s equation was used to correlate the interfacial tension data. The water solubility data were described using an exponential relationship. All the correlations described the experimental physical property data adequately

  15. Long-term observation of water-soluble chemical components in the bulk atmospheric aerosols collected at Okinawa, Japan

    Science.gov (United States)

    Handa, Daishi; Somada, Yuka; Ijyu, Moriaki; Azechi, Sotaro; Nakaema, Fumiya; Arakaki, Takemitsu; Tanahara, Akira

    2010-05-01

    The economic development and population growth in recent Asia spread air pollution. Emission rate of air pollutants from Asia, in particular oxides of nitrogen, surpassed those from North America and Europe and should continue to exceed them for decades. The study of the long-range transported air pollution from Asian continent has gained a special attention in Japan because of increase in photochemical oxidants in relatively remote islands. Okinawa Island is situated approximately 1500 km south of Tokyo, Japan, 2000 km southeast of Beijing, China, and 1000 km south of South Korea. Its location in Asia is well suited for studying long-range transport of air pollutants in East Asia because maritime air mass prevails during summer, while continental air mass dominates during fall, winter, and spring. The maritime air mass data can be seen as background and can be compared with continental air masses which have been affected by anthropogenic activities. Bulk aerosol samples were collected on quartz filters by using a high volume air sampler. Sampling duration was one week for each sample. We determined the concentrations of water-soluble anions, cations and dissolved organic carbon (DOC) in the bulk aerosols collected at the Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) using ion chromatography, atomic absorption spectrometry, and total organic carbon analyzer, respectively. We will report water-soluble chemical components data of anions, cations and DOC in bulk atmospheric aerosols collected at CHAAMS during August, 2005 to April, 2010. Seasonal variation of water-soluble chemical components showed that the concentrations were relatively low in summer, higher in fall and winter, and the highest in spring. When air mass came from Asian Continent, the concentrations of water-soluble chemical components were much higher compared to the other directions. In addition, we calculated background concentration of water-soluble chemical components at Okinawa

  16. Olefin–Styrene Copolymers

    OpenAIRE

    Nunzia Galdi; Antonio Buonerba; Leone Oliva

    2016-01-01

    In this review are reported some of the most relevant achievements in the chemistry of the ethylene–styrene copolymerization and in the characterization of the copolymer materials. Focus is put on the relationship between the structure of the catalyst and that of the obtained copolymer. On the other hand, the wide variety of copolymer architecture is related to the properties of the material and to the potential utility.

  17. Simulated food effects on drug release from ethylcellulose: PVA-PEG graft copolymer-coated pellets.

    Science.gov (United States)

    Muschert, Susanne; Siepmann, Florence; Leclercq, Bruno; Carlin, Brian; Siepmann, Juergen

    2010-02-01

    Food effects might substantially alter drug release from oral controlled release dosage forms in vivo. The robustness of a novel type of controlled release film coating was investigated using various types of release media and two types of release apparatii. Importantly, none of the investigated conditions had a noteworthy impact on the release of freely water-soluble diltiazem HCl or slightly water-soluble theophylline from pellets coated with ethylcellulose containing small amounts of PVA-PEG graft copolymer. In particular, the presence of significant amounts of fats, carbohydrates, surfactants, bile salts, and calcium ions in the release medium did not alter drug release. Furthermore, changes in the pH and differences in the mechanical stress the dosage forms were exposed to did not affect drug release from the pellets. The investigated film coatings allowing for oral controlled drug delivery are highly robust in vitro and likely to be poorly sensitive to classical food effects in vivo.

  18. Photochemical Degradation of Petroleum-Derived Water-Soluble Organics into the Background Dissolved Organic Carbon Pool

    Science.gov (United States)

    Podgorski, D. C.; Ray, P. Z.; Roland, N. V.; Corilo, Y. E.; Tarr, M. A.; Guillemette, F.; Spencer, R. G.

    2016-02-01

    Water-soluble organic (WSO) photoproducts produced from Macondo crude oil (MC252) and a heavy fuel oil (HFO), a surrogate for that which was spilled into the San Francisco Bay by the M/V Cosco Busan, were isolated and irradiated with simulated sunlight to examine the photochemical fate of the products in aquatic ecosystems. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) reveals marked transformations in the elemental composition of WSOs at specific irradiation periods across a time series that correspond with shifts in bulk properties determined with optical measurements. Blue shifts in EEMs spectra correlate with an increase in formulas classified as unsaturated, high oxygen while the polyphenols and unsaturated, low oxygen compounds decrease. The characteristic A and C humic- and fulvic-like FDOM signatures begin to appear in the EEM spectra of WSOs that were irradiated for as little as 8 to 12 hours, the equivalent of 2 to 3 days of natural sunlight. The presence of the A and C signatures correlate to elemental compositions that exhibit a further decrease in the unsaturated, low oxygen and subsequent increase of unsaturated, high oxygen and highly oxygenated aliphatic compounds. Furthermore, van Krevelen plots reveal a shift toward the compositional space associated with carboxyl-rich aromatic moieties (CRAM) as a function of irradiation period and the appearance of the humic- and fulvic-like FDOM signatures in the EEM spectra. Although the photodegraded WSO products show similarities in FDOM and elemental composition to representative natural dissolved organic matter from their respective pools, persistent petroleum signatures that are not photoactive are still detected. Future studies are required to examine the bioavailability of these photodegraded WSO products to determine if they degrade or persist in the environment.

  19. Functional characterization of the water-soluble organic carbon of size-fractionated aerosol in the southern Mississippi Valley

    Science.gov (United States)

    Chalbot, M.-C. G.; Brown, J.; Chitranshi, P.; Gamboa da Costa, G.; Pollock, E. D.; Kavouras, I. G.

    2014-06-01

    The chemical content of water-soluble organic carbon (WSOC) as a function of particle size was characterized in Little Rock, Arkansas in winter and spring 2013. The objectives of this study were to (i) compare the functional characteristics of coarse, fine and ultrafine WSOC and (ii) reconcile the sources of WSOC for periods when carbonaceous aerosol was the most abundant particulate component. The WSOC accounted for 5% of particle mass for particles with dp > 0.96 μm and 10% of particle mass for particles with dp magnetic resonance (1H-NMR). The total non-exchangeable organic hydrogen concentrations varied from 4.1 ± 0.1 nmol m-3 for particles with 1.5 fingerprints of fine particles. Sucrose, fructose, glucose, formate and acetate were associated with coarse particles. These qualitative differences of 1H-NMR profiles for different particle sizes indicated the possible contribution of biological aerosols and a mixture of aliphatic and oxygenated compounds from biomass burning and traffic exhausts. The concurrent presence of ammonium and amines also suggested the presence of ammonium/aminium nitrate and sulfate secondary aerosol. The size-dependent origin of WSOC was further corroborated by the increasing δ13C abundance from -26.81 ± 0.18‰ for the smallest particles to -25.93 ± 0.31‰ for the largest particles and the relative distribution of the functional groups as compared to those previously observed for marine, biomass burning and secondary organic aerosol. The latter also allowed for the differentiation of urban combustion-related aerosol and biological particles. The five types of organic hydrogen accounted for the majority of WSOC for particles with dp > 3.0 μm and dp < 0.96 μm.

  20. Functional characterization of the water-soluble organic carbon of size fractionated aerosol in the Southern Mississippi Valley

    Science.gov (United States)

    Chalbot, M.-C. G.; Brown, J.; Chitranshi, P.; Gamboa da Costa, G.; Pollock, E. D.; Kavouras, I. G.

    2014-02-01

    The chemical content of the water soluble organic carbon (WSOC) as a function of particle size was characterized in Little Rock, Arkansas in winter and spring 2013. The objectives of this study were to: (i) compare the functional characteristics of coarse, fine and ultrafine WSOC and (ii) reconcile the sources of WSOC for the period when carbonaceous aerosol was the most abundant particulate component. The WSOC accounted for 5% of particle mass for particles with dp > 0.96 μm and 10% of particle mass for particles with dp magnetic resonance. The total non-exchangeable organic hydrogen concentrations varied from 4.1 ± 0.1 nmol m-3 for particles with 0.96 fingerprints of fine particles. Sucrose, fructose, glucose, formate and acetate were associated with coarse particles. These qualitative differences of 1H-NMR profiles for different particle sizes indicated the possible contribution of biological aerosol and a mixture of aliphatic and oxygenated compounds from biomass burning and traffic exhausts. The concurrent presence of ammonium and amines also suggested the presence of ammonium/aminium nitrate and sulfate secondary aerosol. The size-dependent origin of WSOC was further corroborated by the increasing δ13C abundance from -26.81 ± 0.18‰ for the smallest particles to -25.93 ± 0.31‰ for the largest particles and the relative distribution of the functional groups as compared to those previously observed for marine, biomass burning and secondary organic aerosol. The latter also allowed for the differentiation of urban combustion-related aerosol and biological particles. The five types of organic hydrogen accounted for the majority of WSOC for particles with dp > 3.0 μm and dp < 0.96 μm.

  1. Nanocomposite formation between alpha-glucosyl stevia and surfactant improves the dissolution profile of poorly water-soluble drug.

    Science.gov (United States)

    Uchiyama, Hiromasa; Tozuka, Yuichi; Nishikawa, Masahiro; Takeuchi, Hirofumi

    2012-05-30

    The formation of a hybrid-nanocomposite using α-glucosyl stevia (Stevia-G) and surfactant was explored to improve the dissolution of flurbiprofen (FP). As reported previously, the dissolution amount of FP was enhanced in the presence of Stevia-G, induced by the formation of an FP and Stevia-G-associated nanostructure. When a small amount of sodium dodecyl sulfate (SDS) was present with Stevia-G, the amount of dissolved FP was extremely enhanced. This dissolution-enhancement effect was also observed with the cationic surfactant of dodecyl trimethyl ammonium bromide, but not with the non-ionic surfactant of n-octyl-β-D-maltopyranoside. To investigate the dissolution-enhancement effect of Stevia-G/SDS mixture, the pyrene I(1)/I(3) ratio was plotted versus the Stevia-G concentration. The pyrene I(1)/I(3) ratio of Stevia-G/SDS mixture had a sigmoidal curve at lower Stevia-G concentrations compared to the Stevia-G solution alone. These results indicate that the Stevia-G/SDS mixture provides a hydrophobic core around pyrene molecules at lower Stevia-G concentrations, leading to nanocomposite formation between Stevia-G and SDS. The nanocomposite of Stevia-G/SDS showed no cytotoxicity to Caco-2 cells at a mixture of 0.1% SDS and 1% Stevia-G solution, whereas 0.1% SDS solution showed high toxicity. These results suggest that the nanocomposite formation of Stevia-G/SDS may be useful way to enhance the dissolution of poorly water-soluble drugs without special treatment. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Seasonal variation of water-soluble inorganic species in the coarse and fine atmospheric aerosols at Dar es Salaam, Tanzania

    International Nuclear Information System (INIS)

    Mkoma, Stelyus L.; Wang Wan; Maenhaut, Willy

    2009-01-01

    The ionic composition of coarse, fine and total PM10 was investigated in aerosol samples collected from a kerbside in Dar es Salaam during the 2005 dry season and 2006 wet season. A 'Gent' PM10 stacked filter unit sampler with sequential Nuclepore polycarbonate filters, providing coarse (8 μm) and fine (0.4 μm) size fractions, was deployed. The mean concentrations and associated standard deviation of fine, coarse and PM10 were, respectively, 17 ± 4, 52 ± 27, and 69 ± 29 μg/m 3 during the 2005 dry season campaign and 13 ± 5, 34 ± 23 and 47 ± 25 μg/m 3 for the 2006 wet season campaign. The higher PM mass concentrations during the dry season campaign are essentially due to soil dust dispersal, much biomass burning and temperature inversions. Chloride, Na + and Mg 2+ were the dominant ions in coarse fraction, indicating a significant influence of sea-salt aerosols. In the fine fraction, SO 4 2- and NH 4 + and K + were the most important ions. The mean equivalent PM2 NO 3 - concentration in the 2005 dry season campaign was two times higher than in the 2006 wet season campaign, probably due to reaction of NaCl (sea-salt) with HNO 3 as a result of higher levels of NO x during the dry season and/or reduced volatilization of NH 4 NO 3 due to lower temperature in the dry season. The results from our water-soluble ions study strongly suggests that biomass burning and secondary aerosols make a significant contribution to fine particulate mass in Dar es Salaam atmosphere. Thus, burning of waste and biomass are thought to be the major causes for the atmospheric particulate pollution in Dar es Salaam during the dry season.

  3. Seasonal variation of water-soluble inorganic species in the coarse and fine atmospheric aerosols at Dar es Salaam, Tanzania

    Science.gov (United States)

    Mkoma, Stelyus L.; Wang, Wan; Maenhaut, Willy

    2009-09-01

    The ionic composition of coarse, fine and total PM10 was investigated in aerosol samples collected from a kerbside in Dar es Salaam during the 2005 dry season and 2006 wet season. A "Gent" PM10 stacked filter unit sampler with sequential Nuclepore polycarbonate filters, providing coarse (8 μm) and fine (0.4 μm) size fractions, was deployed. The mean concentrations and associated standard deviation of fine, coarse and PM10 were, respectively, 17 ± 4, 52 ± 27, and 69 ± 29 μg/m 3 during the 2005 dry season campaign and 13 ± 5, 34 ± 23 and 47 ± 25 μg/m 3 for the 2006 wet season campaign. The higher PM mass concentrations during the dry season campaign are essentially due to soil dust dispersal, much biomass burning and temperature inversions. Chloride, Na + and Mg 2+ were the dominant ions in coarse fraction, indicating a significant influence of sea-salt aerosols. In the fine fraction, SO42- and NH4+ and K + were the most important ions. The mean equivalent PM2 NO3- concentration in the 2005 dry season campaign was two times higher than in the 2006 wet season campaign, probably due to reaction of NaCl (sea-salt) with HNO 3 as a result of higher levels of NO x during the dry season and/or reduced volatilization of NH 4NO 3 due to lower temperature in the dry season. The results from our water-soluble ions study strongly suggests that biomass burning and secondary aerosols make a significant contribution to fine particulate mass in Dar es Salaam atmosphere. Thus, burning of waste and biomass are thought to be the major causes for the atmospheric particulate pollution in Dar es Salaam during the dry season.

  4. Anti-cariogenic properties of a water-soluble extract from cacao.

    Science.gov (United States)

    Ito, Kyoko; Nakamura, Yuko; Tokunaga, Takahisa; Iijima, Daisuke; Fukushima, Kazuo

    2003-12-01

    The addition of a water-soluble extract from cacao-extracted powder (CEPWS) to a cariogenic model food, a white chocolate-like diet that contains 35% sucrose, significantly reduced caries scores in SPF rats infected with Streptococcus sobrinus 6715, compared to control rats fed a white chocolate-like diet. CEPWS markedly inhibited water-insoluble glucan (WIG) synthesis through crude glucosyltransferases (GTFs) from Streptococcus sobrinus B13N in vitro. GTF-inhibitor(s) in CEPWS was prepared through three-step fractionation, and was termed CEPWS-BT, which is a high molecular weight (>10 kDa) heat-stable matrix of sugar, protein, and polyphenol. When the inhibitory effect of CEPWS-BT on glucan synthesis was examined using the purified GTF-I, GTF-T, and GTF-U enzymes from S. sobrinus B13N, significant reduction in GTF-I and GTF-T activity as a result of adding CEPWS-BT at low concentrations was observed. These results suggest that the addition of CEPWS to cariogenic food could be useful in controlling dental caries.

  5. Fluorescent polystyrene photonic crystals self-assembled with water-soluble conjugated polyrotaxanes

    Directory of Open Access Journals (Sweden)

    Francesco Di Stasio

    2013-10-01

    Full Text Available We demonstrate control of the photoluminescence spectra and decay rates of water-soluble green-emitting conjugated polyrotaxanes by incorporating them in polystyrene opals with a stop-band spectrally tuned on the rotaxane emission (405–650 nm. We observe a suppression of the luminescence within the photonic stop-band and a corresponding enhancement of the high-energy edge (405–447 nm. Time-resolved measurements reveal a wavelength-dependent modification of the emission lifetime, which is shortened at the high-energy edge (by ∼11%, in the range 405–447 nm, but elongated within the stop-band (by ∼13%, in the range 448–482 nm. We assign both effects to the modification of the density of photonic states induced by the photonic crystal band structure. We propose the growth of fluorescent composite photonic crystals from blends of “solvent-compatible” non-covalently bonded nanosphere-polymer systems as a general method for achieving a uniform distribution of polymeric dopants in three-dimensional self-assembling photonic structures.

  6. Polymeric Micelles, a Promising Drug Delivery System to Enhance Bioavailability of Poorly Water-Soluble Drugs

    Directory of Open Access Journals (Sweden)

    Wei Xu

    2013-01-01

    Full Text Available Oral administration is the most commonly used and readily accepted form of drug delivery; however, it is find that many drugs are difficult to attain enough bioavailability when administered via this route. Polymeric micelles (PMs can overcome some limitations of the oral delivery acting as carriers able to enhance drug absorption, by providing (1 protection of the loaded drug from the harsh environment of the GI tract, (2 release of the drug in a controlled manner at target sites, (3 prolongation of the residence time in the gut by mucoadhesion, and (4 inhibition of efflux pumps to improve the drug accumulation. To explain the mechanisms for enhancement of oral bioavailability, we discussed the special stability of PMs, the controlled release properties of pH-sensitive PMs, the prolongation of residence time with mucoadhesive PMs, and the P-gp inhibitors commonly used in PMs, respectively. The primary purpose of this paper is to illustrate the potential of PMs for delivery of poorly water-soluble drugs with bioavailability being well maintained.

  7. The mechanisms of drug release from solid dispersions in water-soluble polymers.

    Science.gov (United States)

    Craig, Duncan Q M

    2002-01-14

    Solid dispersions in water-soluble carriers have attracted considerable interest as a means of improving the dissolution rate, and hence possibly bioavailability, of a range of hydrophobic drugs. However, despite the publication of numerous original papers and reviews on the subject, the mechanisms underpinning the observed improvements in dissolution rate are not yet understood. In this review the current consensus with regard to the solid-state structure and dissolution properties of solid dispersions is critically assessed. In particular the theories of carrier- and drug-controlled dissolution are highlighted. A model is proposed whereby the release behaviour from the dispersions may be understood in terms of the dissolution or otherwise of the drug into the concentrated aqueous polymer layer adjacent to the solid surface, including a derivation of an expression to describe the release of intact particles from the dispersions. The implications of a deeper understanding of the dissolution mechanisms are discussed, with particular emphasis on optimising the choice of carrier and manufacturing method and the prediction of stability problems.

  8. Oral formulation strategies to improve solubility of poorly water-soluble drugs.

    Science.gov (United States)

    Singh, Abhishek; Worku, Zelalem Ayenew; Van den Mooter, Guy

    2011-10-01

    In the past two decades, there has been a spiraling increase in the complexity and specificity of drug-receptor targets. It is possible to design drugs for these diverse targets with advances in combinatorial chemistry and high throughput screening. Unfortunately, but not entirely unexpectedly, these advances have been accompanied by an increase in the structural complexity and a decrease in the solubility of the active pharmaceutical ingredient. Therefore, the importance of formulation strategies to improve the solubility of poorly water-soluble drugs is inevitable, thus making it crucial to understand and explore the recent trends. Drug delivery systems (DDS), such as solid dispersions, soluble complexes, self-emulsifying drug delivery systems (SEDDS), nanocrystals and mesoporous inorganic carriers, are discussed briefly in this review, along with examples of marketed products. This article provides the reader with a concise overview of currently relevant formulation strategies and proposes anticipated future trends. Today, the pharmaceutical industry has at its disposal a series of reliable and scalable formulation strategies for poorly soluble drugs. However, due to a lack of understanding of the basic physical chemistry behind these strategies, formulation development is still driven by trial and error.

  9. Synthetic water soluble di-/tritopic molecular receptors exhibiting Ca2+/Mg2+ exchange.

    Science.gov (United States)

    Lavie-Cambot, Aurélie; Tron, Arnaud; Ducrot, Aurélien; Castet, Frédéric; Kauffmann, Brice; Beauté, Louis; Allouchi, Hassan; Pozzo, Jean-Luc; Bonnet, Célia S; McClenaghan, Nathan D

    2017-05-23

    Structural integration of two synthetic water soluble receptors for Ca 2+ and Mg 2+ , namely 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) and o-aminophenol-N,N,O-triacetic acid (APTRA), respectively, gave novel di- and tritopic ionophores (1 and 2). As Mg 2+ and Ca 2+ cannot be simultaneously complexed by the receptors, allosteric control of complexation results. Potentiometric measurements established stepwise protonation constants and showed high affinity for Ca 2+ (log K = 6.08 and 8.70 for 1 and 2, respectively) and an excellent selectivity over Mg 2+ (log K = 3.70 and 5.60 for 1 and 2, respectively), which is compatible with magnesium-calcium ion exchange. While ion-exchange of a single Mg 2+ for a single Ca 2+ is possible in both 1 and 2, the simultaneous binding of two Mg 2+ by 2 appears prohibitive for replacement of these two ions by a single Ca 2+ . Ion-binding and exchange was further rationalized by DFT calculations.

  10. Fluorescence Detection and Discrimination of ss- and ds-DNA with a Water Soluble Oligopyrene Derivative

    Directory of Open Access Journals (Sweden)

    Gaoquan Shi

    2009-06-01

    Full Text Available A novel water-soluble cationic conjugated oligopyrene derivative, oligo(N1,N1,N1,N4,N4,N4-hexamethyl-2-(4-(pyren-1-yl butane-1,4-diaminium bromide (OHPBDB, was synthesized by a combination of chemical and electrochemical synthesis techniques. Each oligomer chain has five pyrene derivative repeating units and brings 10 positive charges. OHPBDB showed high and rapid fluorescence quenching in aqueous media upon addition of trace amounts of single-stranded (ss and double-stranded (ds DNA. The Stern-Volmer constants for ss- and ds-DNA were measured to be as high as 1.3 × 108 mol-1·L and 1.2 × 108 mol-1·L, respectively. On the other hand, distinct fluorescence enhancement of OHPBDB upon addition of large amount of ss-DNA or ds-DNA was observed. Furthermore, ss-DNA showed much stronger fluorescence enhancement than that of ds-DNA, thus yielding a clear and simple signal useful for the discrimination between ss- and ds-DNA in aqueous media.

  11. Water-soluble PEGylated silicon nanoparticles and their assembly into swellable nanoparticle aggregates

    International Nuclear Information System (INIS)

    Xu, Zejing; Li, Yejia; Zhang, Boyu; Purkait, Tapas; Alb, Alina; Mitchell, Brian S.; Grayson, Scott M.; Fink, Mark J.

    2015-01-01

    Water-soluble silicon nanoparticles were synthesized by grafting PEG polymers onto functionalized silicon nanoparticles with distal alkyne or azide moieties. The surface-functionalized silicon nanoparticles were produced in one step from the reactive high-energy ball milling (RHEBM) of silicon wafers with a mixture of either 5-chloro-1-pentyne in 1-pentyne or 1,7 octadiyne in 1-hexyne to afford air and water-stable chloroalkyl or alkynyl-terminated nanoparticles, respectively. Nanoparticles with the ω-chloroalkyl substituents were easily converted to ω-azidoalkyl groups through the reaction of the Si nanoparticles with sodium azide in DMF. The azido-terminated nanoparticles were then grafted with mono-alkynyl-PEG polymers using a copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction to afford core–shell silicon nanoparticles with a covalently attached PEG shell. Covalently linked Si nanoparticle clusters were synthesized via the CuAAC “click” reaction of functional Si NPs with α,ω-functional PEG polymers of various lengths. Dynamic light scattering studies show that the flexible globular nanoparticle aggregates undergo a solvent-dependent change in volume (ethanol > dichloromethane > toluene) similar in behavior to hydrogel nanocomposites

  12. Synthesis of water-soluble curcumin derivatives and their inhibition on lysozyme amyloid fibrillation

    Science.gov (United States)

    Wang, Sujuan; Peng, Xixi; Cui, Liangliang; Li, Tongtong; Yu, Bei; Ma, Gang; Ba, Xinwu

    2018-02-01

    The potential application of curcumin was heavily limited in biomedicine because of its poor solubility in pure water. To circumvent the detracting feature, two novel water-soluble amino acid modified curcumin derivatives (MLC and DLC) have been synthesized through the condensation reaction between curcumin and Nα-Fmoc-Nε-Boc-L-lysine. Benefiting from the enhanced solubility of 3.32 × 10- 2 g/mL for MLC and 4.66 × 10- 2 g/mL for DLC, the inhibition effects of the as-prepared derivatives on the amyloid fibrillation of lysozyme (HEWL) were investigated detaily in water solution. The obtained results showed that the amyloid fibrillation of HEWL was inhibited to a great extent when the concentrations of MLC and DLC reach to 20.139 mM and 49.622 mM, respectively. The fluorescence quenching upon the addition of curcumin to HEWL provide a support for static and dynamic recombination quenching process. The binding driving force was assigned to classical hydrophobic interaction between curcumin derivatives and HEWL. In addition, UV-Vis absorption and circular dichroism (CD) spectra confirmed the change of the conformation of HEWL.

  13. Synthesis of Water-Soluble Antimony Sulfide Quantum Dots and Their Photoelectric Properties.

    Science.gov (United States)

    Zhu, Jiang; Yan, Xuelian; Cheng, Jiang

    2018-01-15

    Antimony sulfide (Sb 2 S 3 ) has been applied in photoelectric devices for a long time. However, there was lack of information about Sb 2 S 3 quantum dots (QDs) because of the synthesis difficulties. To fill this vacancy, water-soluble Sb 2 S 3 QDs were prepared by hot injection using hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) mixture as anionic-cationic surfactant, alkanol amide (DEA) as stabilizer, and ethylenediaminetetraacetic acid (EDTA) as dispersant. Photoelectric properties including absorbing and emission were characterized by UV-Vis-IR spectrophotometer and photoluminescence (PL) spectroscopic technique. An intensive PL emission at 880 nm was found, indicating Sb 2 S 3 QDs have good prospects in near-infrared LED and near-infrared laser application. Sb 2 S 3 QD thin films were prepared by self-assembly growth and then annealed in argon or selenium vapor. Their band gaps (E g s) were calculated according to transmittance spectra. The E g of Sb 2 S 3 QD thin film has been found to be tunable from 1.82 to 1.09 eV via annealing or selenylation, demonstrating the good prospects in photovoltaic application.

  14. Debinding behaviour of a water soluble PEG/PMMA binder for Ti metal injection moulding

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Gang [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Cao, Peng, E-mail: p.cao@auckland.ac.nz [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Wen, Guian [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Edmonds, Neil [School of Chemical Science, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand)

    2013-05-15

    Polyethylene glycol (PEG) has been becoming a common component in the design of water soluble binder systems for metal injection moulding. Similar to solvent debinding, PEG can be leached out by water and the mechanism of debinding was proposed in the literature with somehow misleading information about the debinding mechanism, particularly about the formation of PEG gel. This work investigates the debinding behaviours of a PEG-based binder in titanium compacts. Titanium powder is formulated with PEG, poly(methyl methacrylate) (PMMA) and stearic acid (SA) to formulate titanium feedstock. To determine the debinding kinetics, the PEG removal percentages are measured at three different temperatures and for various specimen thicknesses. A mathematic model based on diffusion-controlled debinding process is established. The evolution of porous microstructure during the water debinding process is observed using scanning electron microscopy. Based on these observations, a water debinding mechanism for titanium alloy compacts formulated with PEG-based binders is proposed. - Highlights: ► The water-debinding behaviours of the PEG binder system were investigated. ► PEG dissolution and transportation, and the pore structure development. ► A water debinding mechanism of PEG-based binders is proposed. ► Incorrect explanation of PEG gelling in the literature is corrected. ► Correction/modification made as per the reviewers' comments and suggestions.

  15. Selective Organic and Organometallic Reactions in Water-Soluble Host-Guest Supramolecular Systems

    Energy Technology Data Exchange (ETDEWEB)

    Pluth, Michael D.; Raymond, Kenneth N.; Bergman, Robert G.

    2008-02-16

    Inspired by the efficiency and selectivity of enzymes, synthetic chemists have designed and prepared a wide range of host molecules that can bind smaller molecules with their cavities; this area has become known as 'supramolecular' or 'host-guest' chemistry. Pioneered by Lehn, Cram, Pedersen, and Breslow, and followed up by a large number of more recent investigators, it has been found that the chemical environment in each assembly - defined by the size, shape, charge, and functional group availability - greatly influences the guest-binding characteristics of these compounds. In contrast to the large number of binding studies that have been carried out in this area, the exploration of chemistry - especially catalytic chemistry - that can take place inside supramolecular host cavities is still in its infancy. For example, until the work described here was carried out, very few examples of organometallic reactivity inside supramolecular hosts were known, especially in water solution. For that reason, our group and the group directed by Kenneth Raymond decided to take advantage of our complementary expertise and attempt to carry out metal-mediated C-H bond activation reactions in water-soluble supramolecular systems. This article begins by providing background from the Raymond group in supramolecular coordination chemistry and the Bergman group in C-H bond activation. It goes on to report the results of our combined efforts in supramolecular C-H activation reactions, followed by extensions of this work into a wider range of intracavity transformations.

  16. Preparation of water-soluble carbon nanotubes using a pulsed streamer discharge in water

    International Nuclear Information System (INIS)

    Imasaka, Kiminobu; Suehiro, Junya; Kanatake, Yusuke; Kato, Yuki; Hara, Masanori

    2006-01-01

    A novel technique for the preparation of water-soluble carbon nanotubes was demonstrated using a pulsed streamer discharge generated in water. The technique involved chemical reactions between radicals generated by the pulsed streamer discharge and carbon nanotubes. The pulsed streamer-treated carbon nanotubes were homogeneously dispersed and well solubilized in water for a month or longer. The mechanism of solubilization of carbon nanotubes by the pulsed streamer discharge is discussed based on FTIR spectroscopy and optical emission spectra measurements. FTIR spectroscopy revealed that -OH groups, which are known to impart a hydrophilic nature to carbon material, were introduced on the carbon nanotube surface. Optical emission spectra from the pulsed streamer plasma showed that highly oxidative O * and H * radicals were generated in water. These results suggest that the functionalization of the carbon nanotube surface by -OH group can be attributed to the O * and H * radicals. An advantage of the proposed method is that there is no need for any chemical agents or additives for solubilization. Chemical agents for solubilization are generated from the water itself by the electrochemical reactions induced by the pulsed streamer discharge

  17. Investigation of water-soluble elastin as a multifunctional cosmetic material: Moisturizing and whitening effects.

    Science.gov (United States)

    Inoue, Asako; Hikima, Tomohiro; Taniguchi, Suguru; Nose, Takeru; Maeda, Iori

    Elastin and collagen are extracellular matrix proteins that are widely distributed in the body. Although elastin essentially functions as a skin moisturizer, there have been few reports on its other fundamental chemical and biological functions. In this study, we investigated the moisturizing and whitening (tyrosinase inhibition) effects of elastin to examine its usefulness as a cosmetic material. Water-soluble hot alkali pig aorta (HAPA)-elastin was prepared from pig aorta using the hot alkali method. HAPA-elastin showed a widely distributed molecular weight and had a coacervation property that mediated reversible self-assembly of its molecules with increasing temperature. Amino acid analysis of HAPA-elastin showed a high content (81.5%) of hydrophobic amino acids such as Gly, Ala, Val, and Pro. Des (desmosine) and Ide (isodesmosine), which are characteristic amino acids of elastin, accounted for more than 0.4% of the total amino acid content. HAPA-elastin showed a moisture-retaining property. The water content of skin samples treated with and without HAPA-elastin was 77.2% ± 7.8% and 49.4% ± 10.1%, respectively. HAPA-elastin also inhibited tyrosinase activity by 11.3% ± 3.9%. The results obtained indicate that elastin has a useful function as a cosmetic material.

  18. Synthesis and photophysicochemical studies of a water soluble conjugate between folic acid and zinc tetraaminophthalocyanine

    Energy Technology Data Exchange (ETDEWEB)

    Khoza, Phindile; Antunes, Edith [Department of Chemistry, Rhodes University, PO Box 94, Grahamstown (South Africa); Chen, Ji-Yao [State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433 (China); Nyokong, Tebello, E-mail: t.nyokong@ru.ac.za [Department of Chemistry, Rhodes University, PO Box 94, Grahamstown (South Africa)

    2013-02-15

    This work reports on the synthesis of zinc tetraaminophthalocyanine (ZnTAPc) functionalized with folic acid (FA), forming ZnTAPcFA. The conjugate between FA and ZnTAPc was soluble in water whereas ZnTAPc alone is not. The structure of ZnTAPcFA conjugate was elucidated by {sup 1}H NMR, MALDI-TOF mass and FTIR spectra. Photophysical and photochemical studies of ZnTAPcFA were conducted in DMSO. The increase in fluorescence quantum yield of the conjugate was accompanied by a decrease in the triplet and singlet oxygen quantum yields. The changes in triplet quantum and singlet oxygen quantum yields were marginal when ZnTAPc was simply mixed with FA without a chemical bond. - Highlights: Black-Right-Pointing-Pointer A conjugate between folic acid and a zinc tetraaminophthalocyanine was formed. Black-Right-Pointing-Pointer The conjugate is water soluble even though the phthalocyanine alone is not. Black-Right-Pointing-Pointer The fluorescence quantum yield of the conjugate was enhanced compared to the phthalocyanine alone. Black-Right-Pointing-Pointer Triplet quantum yields decreased for the conjugate.

  19. Synthesis and characterization of gold cubic nanoshells using water-soluble GeO₂templates.

    Science.gov (United States)

    Wang, Cen; Tang, Peisong; Ge, Mingyuan; Xu, Xiaobin; Cao, Feng; Jiang, J Z

    2011-04-15

    Size-tunable GeO₂ nanocubes were initially prepared by a modified sono-assisted reverse micelle method and then functionalized with an amino-terminated silanizing agent. Subsequently, gold decorated GeO₂ nanocomposites were prepared at pH ≈ 7 and 80 °C. It was found that well-dispersed gold nanoparticles on GeO₂ nanocubes could be obtained only if gold salt is abundant to favor simultaneous, homogeneous nucleation of gold particles. Additional gold ions were reduced onto these attached 'seed' particles accompanied by synchronous dissolution of water-soluble GeO₂ cores, resulting in gold hollow cubic shells. The GeO₂ nanocubes and Au/GeO₂ nanocomposites as well as gold hollow cubic shells were characterized by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and UV-visible spectroscopy. In particular, gold hollow cubic shells feature a plasmon resonance peak at above 900 nm, which renders it quite promising in biochemical applications.

  20. Synthesis and characterization of gold cubic nanoshells using water-soluble GeO2 templates

    Science.gov (United States)

    Wang, Cen; Tang, Peisong; Ge, Mingyuan; Xu, Xiaobin; Cao, Feng; Jiang, J. Z.

    2011-04-01

    Size-tunable GeO2 nanocubes were initially prepared by a modified sono-assisted reverse micelle method and then functionalized with an amino-terminated silanizing agent. Subsequently, gold decorated GeO2 nanocomposites were prepared at pH ≈ 7 and 80 °C. It was found that well-dispersed gold nanoparticles on GeO2 nanocubes could be obtained only if gold salt is abundant to favor simultaneous, homogeneous nucleation of gold particles. Additional gold ions were reduced onto these attached 'seed' particles accompanied by synchronous dissolution of water-soluble GeO2 cores, resulting in gold hollow cubic shells. The GeO2 nanocubes and Au/GeO2 nanocomposites as well as gold hollow cubic shells were characterized by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and UV-visible spectroscopy. In particular, gold hollow cubic shells feature a plasmon resonance peak at above 900 nm, which renders it quite promising in biochemical applications.

  1. Synthesis and characterization of gold cubic nanoshells using water-soluble GeO2 templates

    International Nuclear Information System (INIS)

    Wang Cen; Ge Mingyuan; Xu Xiaobin; Jiang, J Z; Tang Peisong; Cao Feng

    2011-01-01

    Size-tunable GeO 2 nanocubes were initially prepared by a modified sono-assisted reverse micelle method and then functionalized with an amino-terminated silanizing agent. Subsequently, gold decorated GeO 2 nanocomposites were prepared at pH ∼ 7 and 80 deg. C. It was found that well-dispersed gold nanoparticles on GeO 2 nanocubes could be obtained only if gold salt is abundant to favor simultaneous, homogeneous nucleation of gold particles. Additional gold ions were reduced onto these attached 'seed' particles accompanied by synchronous dissolution of water-soluble GeO 2 cores, resulting in gold hollow cubic shells. The GeO 2 nanocubes and Au/GeO 2 nanocomposites as well as gold hollow cubic shells were characterized by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and UV-visible spectroscopy. In particular, gold hollow cubic shells feature a plasmon resonance peak at above 900 nm, which renders it quite promising in biochemical applications.

  2. Water-soluble quercetin modulates the choleresis and bile lipid ratio in rats.

    Science.gov (United States)

    Vovkun, Tatiana; Yanchuk, Petro; Shtanova, Lidiya; Veselskiy, Stanislav; Filimonova, Natalia; Shalamay, Anatoly; Vedmid, Volodymyr

    2018-01-01

    Water-soluble analogue of quercetin, corvitin is used in patients with myocardial infarction as blocker of 5-lipoxygenase. However, its effects on secretion, lipid content and physico-chemical properties of bile have not been understood yet. We investigated the effect of corvitin, applied in different doses, on the level of bile flow, the content of bile free and esterified cholesterol, phospholipids, triacylglycerols, and free fatty acids. In order to determine stability of the bile colloidal system, we examined the relationship between different lipid components. The rats were injected intraportally with a bolus of corvitin. At doses of 2.5, 5, and 10 mg/kg, the latter increased bile flow and concentration of total cholates, as well as free fatty acids. Corvitin (5 mg/kg) elevated phospholipids and cholesterol content, but at a dose of 10 mg/kg it increased the concentration of bile cholesterol esters and triacylglycerols. Corvitin applied at doses of 2.5 and 10 mg/kg increased total cholates/cholesterol ratio, but at a dose of 10 mg/kg, the drug reduced cholesterol / esterified cholesterol ratio. The results suggest that corvitin exerts choleretic effect and improves stability of bile colloidal system.

  3. Template occluded SBA-15: An effective dissolution enhancer for poorly water-soluble drug

    Energy Technology Data Exchange (ETDEWEB)

    Fu Tingming, E-mail: futingming@gmail.com [College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210029 (China); Guo Liwei; Le Kang; Wang Tianyao; Lu Jin [College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210029 (China)

    2010-09-15

    The aim of the present work was to improve the dissolution rate of piroxicam by inclusion into template occluded SBA-15. Our strategy involves directly introducing piroxicam into as-prepared SBA-15 occluded with P123 (EO{sub 20}PO{sub 70}EO{sub 20}) by self assembling method in acetonitrile/methylene chloride mixture solution. Ultraviolet spectrometry experiment and thermogravimetric analysis-differential scanning calorimetry (TG-DSC) profiles show that the piroxicam and P123 contents in the inclusion compound are 12 wt% and 28 wt%, respectively. X-ray powder diffraction and DSC analysis reveal that the included piroxicam is arranged in amorphous form. N{sub 2} adsorption-desorption experiment indicates that the piroxicam has been introduced to the mesopores instead of precipitating at the outside of the silica material. The inclusion compound was submitted to in vitro dissolution tests, the results show that the piroxicam dissolve from template occluded inclusion compound more rapidly, than these from the piroxicam crystalline and template removed samples in all tested conditions. Thus a facile method to improve the dissolution rate of poorly water-soluble drug was established, and this discovery opens a new avenue for the utilization of templates used for the synthesis of mesoporous materials.

  4. Hygroscopic behavior of atmospheric aerosols containing nitrate salts and water-soluble organic acids

    Science.gov (United States)

    Jing, Bo; Wang, Zhen; Tan, Fang; Guo, Yucong; Tong, Shengrui; Wang, Weigang; Zhang, Yunhong; Ge, Maofa

    2018-04-01

    While nitrate salts have critical impacts on environmental effects of atmospheric aerosols, the effects of coexisting species on hygroscopicity of nitrate salts remain uncertain. The hygroscopic behaviors of nitrate salt aerosols (NH4NO3, NaNO3, Ca(NO3)2) and their internal mixtures with water-soluble organic acids were determined using a hygroscopicity tandem differential mobility analyzer (HTDMA). The nitrate salt / organic acid mixed aerosols exhibit varying phase behavior and hygroscopic growth depending upon the type of components in the particles. Whereas pure nitrate salt particles show continuous water uptake with increasing relative humidity (RH), the deliquescence transition is still observed for ammonium nitrate particles internally mixed with organic acids such as oxalic acid and succinic acid with a high deliquescence point. The hygroscopicity of submicron aerosols containing sodium nitrate and an organic acid is also characterized by continuous growth, indicating that sodium nitrate tends to exist in a liquid-like state under dry conditions. It is observed that in contrast to the pure components, the water uptake is hindered at low and moderate RH for calcium nitrate particles containing malonic acid or phthalic acid, suggesting the potential effects of mass transfer limitation in highly viscous mixed systems. Our findings improve fundamental understanding of the phase behavior and water uptake of nitrate-salt-containing aerosols in the atmospheric environment.

  5. Modeling the Release Kinetics of Poorly Water-Soluble Drug Molecules from Liposomal Nanocarriers

    Directory of Open Access Journals (Sweden)

    Stephan Loew

    2011-01-01

    Full Text Available Liposomes are frequently used as pharmaceutical nanocarriers to deliver poorly water-soluble drugs such as temoporfin, cyclosporine A, amphotericin B, and paclitaxel to their target site. Optimal drug delivery depends on understanding the release kinetics of the drug molecules from the host liposomes during the journey to the target site and at the target site. Transfer of drugs in model systems consisting of donor liposomes and acceptor liposomes is known from experimental work to typically exhibit a first-order kinetics with a simple exponential behavior. In some cases, a fast component in the initial transfer is present, in other cases the transfer is sigmoidal. We present and analyze a theoretical model for the transfer that accounts for two physical mechanisms, collisions between liposomes and diffusion of the drug molecules through the aqueous phase. Starting with the detailed distribution of drug molecules among the individual liposomes, we specify the conditions that lead to an apparent first-order kinetic behavior. We also discuss possible implications on the transfer kinetics of (1 high drug loading of donor liposomes, (2 attractive interactions between drug molecules within the liposomes, and (3 slow transfer of drugs between the inner and outer leaflets of the liposomes.

  6. Water-Soluble Cellulose Derivatives Are Sustainable Additives for Biomimetic Calcium Phosphate Mineralization

    Directory of Open Access Journals (Sweden)

    Andreas Taubert

    2016-10-01

    Full Text Available The effect of cellulose-based polyelectrolytes on biomimetic calcium phosphate mineralization is described. Three cellulose derivatives, a polyanion, a polycation, and a polyzwitterion were used as additives. Scanning electron microscopy, X-ray diffraction, IR and Raman spectroscopy show that, depending on the composition of the starting solution, hydroxyapatite or brushite precipitates form. Infrared and Raman spectroscopy also show that significant amounts of nitrate ions are incorporated in the precipitates. Energy dispersive X-ray spectroscopy shows that the Ca/P ratio varies throughout the samples and resembles that of other bioinspired calcium phosphate hybrid materials. Elemental analysis shows that the carbon (i.e., polymer contents reach 10% in some samples, clearly illustrating the formation of a true hybrid material. Overall, the data indicate that a higher polymer concentration in the reaction mixture favors the formation of polymer-enriched materials, while lower polymer concentrations or high precursor concentrations favor the formation of products that are closely related to the control samples precipitated in the absence of polymer. The results thus highlight the potential of (water-soluble cellulose derivatives for the synthesis and design of bioinspired and bio-based hybrid materials.

  7. Water-Soluble Chlorophyll Protein (WSCP) Stably Binds Two or Four Chlorophylls.

    Science.gov (United States)

    Palm, Daniel M; Agostini, Alessandro; Tenzer, Stefan; Gloeckle, Barbara M; Werwie, Mara; Carbonera, Donatella; Paulsen, Harald

    2017-03-28

    Water-soluble chlorophyll proteins (WSCPs) of class IIa from Brassicaceae form tetrameric complexes containing one chlorophyll (Chl) per apoprotein but no carotenoids. The complexes are remarkably stable toward dissociation and protein denaturation even at 100 °C and extreme pH values, and the Chls are partially protected against photooxidation. There are several hypotheses that explain the biological role of WSCPs, one of them proposing that they function as a scavenger of Chls set free upon plant senescence or pathogen attack. The biochemical properties of WSCP described in this paper are consistent with the protein acting as an efficient and flexible Chl scavenger. At limiting Chl concentrations, the recombinant WSCP apoprotein binds substoichiometric amounts of Chl (two Chls per tetramer) to form complexes that are as stable toward thermal dissociation, denaturation, and photodamage as the fully pigmented ones. If more Chl is added, these two-Chl complexes can bind another two Chls to reach the fully pigmented state. The protection of WSCP Chls against photodamage has been attributed to the apoprotein serving as a diffusion barrier for oxygen, preventing its access to triplet excited Chls and, thus, the formation of singlet oxygen. By contrast, the sequential binding of Chls by WSCP suggests a partially open or at least flexible structure, raising the question of how WSCP photoprotects its Chls without the help of carotenoids.

  8. Template occluded SBA-15: An effective dissolution enhancer for poorly water-soluble drug

    International Nuclear Information System (INIS)

    Fu Tingming; Guo Liwei; Le Kang; Wang Tianyao; Lu Jin

    2010-01-01

    The aim of the present work was to improve the dissolution rate of piroxicam by inclusion into template occluded SBA-15. Our strategy involves directly introducing piroxicam into as-prepared SBA-15 occluded with P123 (EO 20 PO 70 EO 20 ) by self assembling method in acetonitrile/methylene chloride mixture solution. Ultraviolet spectrometry experiment and thermogravimetric analysis-differential scanning calorimetry (TG-DSC) profiles show that the piroxicam and P123 contents in the inclusion compound are 12 wt% and 28 wt%, respectively. X-ray powder diffraction and DSC analysis reveal that the included piroxicam is arranged in amorphous form. N 2 adsorption-desorption experiment indicates that the piroxicam has been introduced to the mesopores instead of precipitating at the outside of the silica material. The inclusion compound was submitted to in vitro dissolution tests, the results show that the piroxicam dissolve from template occluded inclusion compound more rapidly, than these from the piroxicam crystalline and template removed samples in all tested conditions. Thus a facile method to improve the dissolution rate of poorly water-soluble drug was established, and this discovery opens a new avenue for the utilization of templates used for the synthesis of mesoporous materials.

  9. Effect of extraction methods on property and bioactivity of water-soluble polysaccharides from Amomum villosum.

    Science.gov (United States)

    Yan, Yajuan; Li, Xia; Wan, Mianjie; Chen, Jingping; Li, Shijie; Cao, Man; Zhang, Danyan

    2015-03-06

    In the present study, effect of different extraction methods on property and bioactivity of water-soluble polysaccharides (WSP) from the seeds of Amomum villosum were investigated. Firstly, four different extraction methods were used to extract WSP, which include hot water extraction (HWE), ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE) and enzyme-assisted extraction (EAE). As a result, four WSP samples, WSP(H), WSP(U), WSP(M) and WSP(E) were acquired. Then, the difference of four WSP samples in yield, characterization and antioxidant activities in vitro were further compared. Experimental results showed that the four WSP samples had the same monosaccharide composition, but mere difference in the content; they all had typical IR spectra characteristic of polysaccharides. WSP(U) contained the highest contents of uronic acid and sulfate. The yield of WSP(U) was the highest and its antioxidant activity was the best. These results suggested that ultrasonic-assisted extraction was the best extraction method for WSP. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Toxicity evaluation of boron nitride nanospheres and water-soluble boron nitride in Caenorhabditis elegans.

    Science.gov (United States)

    Wang, Ning; Wang, Hui; Tang, Chengchun; Lei, Shijun; Shen, Wanqing; Wang, Cong; Wang, Guobin; Wang, Zheng; Wang, Lin

    2017-01-01

    Boron nitride (BN) nanomaterials have been increasingly explored for potential biological applications. However, their toxicity remains poorly understood. Using Caenorhabditis elegans as a whole-animal model for toxicity analysis of two representative types of BN nanomaterials - BN nanospheres (BNNSs) and highly water-soluble BN nanomaterial (named BN-800-2) - we found that BNNSs overall toxicity was less than soluble BN-800-2 with irregular shapes. The concentration thresholds for BNNSs and BN-800-2 were 100 µg·mL -1 and 10 µg·mL -1 , respectively. Above this concentration, both delayed growth, decreased life span, reduced progeny, retarded locomotion behavior, and changed the expression of phenotype-related genes to various extents. BNNSs and BN-800-2 increased oxidative stress levels in C. elegans by promoting reactive oxygen species production. Our results further showed that oxidative stress response and MAPK signaling-related genes, such as GAS1 , SOD2 , SOD3 , MEK1 , and PMK1 , might be key factors for reactive oxygen species production and toxic responses to BNNSs and BN-800-2 exposure. Together, our results suggest that when concentrations are lower than 10 µg·mL -1 , BNNSs are more biocompatible than BN-800-2 and are potentially biocompatible material.

  11. Water-soluble graphene grafted by poly(sodium 4-styrenesulfonate) for enhancement of electric capacitance

    International Nuclear Information System (INIS)

    Du Feipeng; Wang Jingjing; Tang, Chak-Yin; Tsui, Chi-Pong; Zhou Xingping; Xie Xiaolin; Liao Yonggui

    2012-01-01

    Water-soluble poly(sodium 4-styrenesulfonate) modified graphene (PSSS-GR) was successfully synthesized via covalently grafting poly(sodium 4-styrenesulfonate) (PSSS) on the surfaces of graphene (GR) nanosheets. The structure of PSSS-GR was investigated with Fourier transform infrared, x-ray photoelectron and Raman spectroscopy, thermogravimetric analysis, transmission and scanning electron microscopy and atomic force microscopy. The PSSS chains made the GR nanosheets fully exfoliate into a single-layer structure, and the PSSS layer on GR reached 90 wt%. PSSS chains displayed mutually repulsive effects on promoting GR sheets that were more stable in water. The performances of supercapacitors made of PSSS-GR and unmodified GR electrodes were compared using cyclic voltammetry and galvanostatic charge/discharge techniques. The results showed that PSSS is an effective binder for graphene sheets and can increase the specific capacitance of PSSS-GR based supercapacitors and improve their rate capability. The maximum specific capacitance of the PSSS-GR based supercapacitor was 210 F g −1 at 5 A g −1 , which was 166% higher than for one made of unmodified graphene electrodes. Electrochemical impedance spectroscopy demonstrated fast ion diffusion in the PSSS-GR electrode structure. PSSS-GR based supercapacitors can fulfil one of the essential requirements for potential electric energy storage applications. (paper)

  12. Reverse micelle-based water-soluble nanoparticles for simultaneous bioimaging and drug delivery.

    Science.gov (United States)

    Chen, Ying; Liu, Yong; Yao, Yongchao; Zhang, Shiyong; Gu, Zhongwei

    2017-04-11

    With special confined water pools, reverse micelles (RMs) have shown potential for a wide range of applications. However, the inherent water-insolubility of RMs hinders their further application prospects, especially for applications related to biology. We recently reported the first successful transfer of RMs from organic media to an aqueous phase without changing the smart water pools by the hydrolysis of an arm-cleavable interfacial cross-linked reverse micelles. Herein, we employed another elaborate amphiphile 1 to construct new acrylamide-based cross-linked water-soluble nanoparticles (ACW-NPs) under much gentler conditions. The special property of the water pools of the ACW-NPs was confirmed by both the Förster resonance energy transfer (FRET) between 5-((2-aminoethyl)amino)naphthalene-1-sulfonic acid (1,5-EDANS) and benzoic acid, 4-[2-[4-(dimethylamino)phenyl]diazenyl] (DABCYL) and satisfactory colloidal stability in 10% fetal bovine serum. Importantly, featured by the gentle synthetic strategy, confined water pool, and carboxylic acid-functionalized surface, the new ACW-NPs are well suitable for biological applications. As an example, the fluorescent reagent 8-hydroxy-1,3,6-pyrenetrisulfonic acid trisodium salt (HPTS) was encapsulated in the core and simultaneously, the anticancer drug gemcitabine (Gem) was covalently conjugated onto the surface exterior. As expected, the resulting multifunctional ACW-NPs@HPTS@Gem exhibits a high imaging effect and anticancer activity for non-small lung cancer cells.

  13. The haemodynamic effects of iodinated water soluble radiographic contrast media: a review

    International Nuclear Information System (INIS)

    Morcos, S.K.; Dawson, P.; Pearson, J.D.; Jeremy, J.Y.; Davenport, A.P.; Yates, M.S.; Tirone, P.; Cipolla, P.; Haeen, C. de; Muschick, P.; Krause, W.; Refsum, H.; Emery, C.J.; Liss, Per; Nygren, A.; Haylor, J.; Pugh, N.D.; Karlsson, J.O.G.

    1998-01-01

    All classes of iodinated water-soluble radiographic contrast media (RCM) are vasoactive with the iso-osmolar dimers inducing the least changes in the vascular tone. The mechanisms responsible for RCM-induced changes in the vascular tone are not fully understood and could be multifactorial. A direct effect on the vascular smooth muscle cells causing alterations in the ion exchanges across the cell membrane is thought to be an important factor in RCM-induced vasodilatation. The release of the endogenous vasoactive mediators adenosine and endothelin may also play a crucial role in the haemodynamic effects of RCM particularly in the kidney. In addition, the effects of RCM on blood rheology can cause a reduction in the blood flow in the microcirculation. The purpose of this review is to discuss the pathophysiology of the haemodynamic effects of RCM and to offer some insight into the biology of the endothelium and vascular smooth muscle cells as well as the pharmacology of the important vasoactive mediators endothelin and adenosine

  14. The effects of water soluble contrast agents on the respiratory tract

    International Nuclear Information System (INIS)

    Lovett, I.; Donchey, S.; Doust, B.; Branson, J.; Munro, V.

    1989-01-01

    The water soluble contrast agents Gastrografin R (Sodium diatrizoate and meglumine diatrizoate, Schering, Berlin), Iopamiro 300 R (Iopamidol, Schering, Berlin), and Dionosil Aqueous R (propyliodone BP, Glaxo, England) were instilled into the tracheobronchial tree of rats in doses of either 0.1 ml and 0.25 ml. Rats being used as controls, underwent sham operations with the instillation of air instead of contrast agent. In all, 85 rats were used. All rats that had not already died from the effects of contrast agent were sacrificed 30 minutes after instillation. The relative effects of the contrast agents were measured by comparing: survival time; radiographic effects of the contrast agents on the lungs; and pathological changes as estimated by post mortem lung section and microscopy. The least toxic agent was the one with the lowest osmotic activity, namely Aqueous Dionosil. It is therefore recommended that Aqueous Dionosil be used in preference to Gastrografin or Iopamidol for studies of the oesophagus whenever there is a danger of aspiration of contrast agent into the tracheobronchial tree. 11 refs., 3 figs., 5 tabs

  15. Water-soluble coenzyme Q10 formulation (Q-TER(®)) in the treatment of presbycusis.

    Science.gov (United States)

    Salami, Angelo; Mora, Renzo; Dellepiane, Massimo; Manini, Giorgio; Santomauro, Valentina; Barettini, Luciano; Guastini, Luca

    2010-10-01

    These preliminary data are encouraging for a larger clinical trial to collect additional evidence on the effect of Q-TER(®) in preventing the development of hearing loss in subjects with presbycusis. The purpose of this study was to evaluate the efficiency and applicability of a water-soluble formulation of CoQ10 (Q-TER(®)) in subjects with presbycusis. A total of 60 patients with presbycusis were included and divided into three numerically equal groups. Group A underwent therapy with Q-TER(®), 160 mg, once a day for 30 days; group B underwent therapy with vitamin E (50 mg), once a day for 30 days; group C received placebo, once a day for 30 days. Before and at the end of the treatment, all patients underwent pure tone audiometry, transient evoked otoacoustic emissions, otoacoustic products of distortion, auditory brainstem response, and speech audiometry. Compared with group B, at the end of the treatment in group A the liminar tonal audiometry showed a significant improvement of the air and bone thresholds at the 1000 (14/20 vs 9/20), 2000 (14/20 vs 7/20), 4000 (15/20 vs 6/20), and 8000 Hz (13/20 vs 5/20). We found no significant differences in the other parameters and in group C.

  16. Improving the water solubility of Monascus pigments under acidic conditions with gum arabic.

    Science.gov (United States)

    Jian, Wenjie; Sun, Yuanming; Wu, Jian-Yong

    2017-07-01

    Monascus pigments (Mps) are natural food colorants and their stability in acidic solutions is important for application in the food industry. This study aimed to evaluate the use of gum arabic (GA) as a stabilizer for maintaining the solubility of Mps in an acidic aqueous solution exposed to a high temperature, and to analyze the molecular interactions between GA and Mps. Mps dispersed (0.2 g kg -1 ) in deionized water at pH 3.0-4.0 without GA formed precipitates but remained in a stable solution in the presence of GA (1 g kg -1 ). The significant improvement of Mps water solubility under acidic conditions was attributed to the formation of Mps-GA complexes, as indicated by a sharp increase in the fluorescence intensity. The results on particle size, zeta potential, and transmission electron microscopy further suggested that molecular binding of Mps to GA, electrostatic repulsion, and steric hindrance of GA were contributing factors to preventing the aggregation of Mps in acidic solutions. A mechanistic model was presented for GA-Mps interactions and complex structures. GA was proven to be an effective stabilizer of natural food colorants in acidic solutions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  17. Synthesis of water soluble CdS nanoparticles and study of their DNA damage activity

    Directory of Open Access Journals (Sweden)

    Kumar Suranjit Prasad

    2017-05-01

    Full Text Available This study reports a novel method for preparation of water soluble CdS nanoparticles using leaf extract of a plant, Asparagus racemosus. The extract of the leaf tissue which worked as a stabilizing and capping agent, assisted the formation of nanoparticles. Nanoparticles were characterized using a UV–vis spectrophotometer, Photoluminescence, TEM, EDAX, XRD and FT-IR. Transmission electron microscopy followed by selected area electron diffraction pattern analysis indicated the formation of spherical, polydispersed, crystalline, CdS of diameter ranging from 2 to 8 nm. X-ray diffraction studies showed the formation of 111, 220 and 311 planes of face-centered cubic (fcc CdS. EDAX analysis confirmed the presence of Cd and S in nanosphere. The cytotoxicity test using MTT assay as well as DNA damage analysis using comet assay revealed that synthesized nano CdS quantum dots (QDs caused less DNA damage and cell death of lymphocytes than pure CdS nanoparticles.

  18. Water-soluble coenzyme Q10 formulation in presbycusis: long-term effects.

    Science.gov (United States)

    Guastini, Luca; Mora, Renzo; Dellepiane, Massimo; Santomauro, Valentina; Giorgio, Manini; Salami, Angelo

    2011-05-01

    These findings provide the basis for understanding the duration of the effect after the last use of the drug and encourage a larger clinical trial to collect additional evidence on the effect of coenzyme Q10 (CoQ10) in preventing the development of hearing loss in subjects with presbycusis. The aim of this study was to evaluate the long-term effects of a water-soluble formulation of CoQ10 (Q-TER) in subjects with presbycusis. Sixty patients with presbycusis were included and divided at random into three numerically equal groups. For 30 days, group A underwent therapy with Q-TER, group B underwent therapy with vitamin E, and group C received placebo. Before, at the end, and 6 months after the end of the treatment, all patients underwent evaluation of pure tone audiometry, transient evoked otoacoustic emissions and otoacoustic products of distortion, auditory brainstem response, and speech audiometry. Compared with group B, at the end of the treatment in group A the pure tone audiometry showed a significant (p < 0.05) improvement of the audiometric thresholds at 1000, 2000, 4000, and 8000 Hz. This improvement was confirmed by the speech audiometry and last check. We found no significant differences in the other parameters and in group C.

  19. Highly Water-Soluble Magnetic Nanoparticles as Novel Draw Solutes in Forward Osmosis for Water Reuse

    KAUST Repository

    Ling, Ming Ming

    2010-06-16

    Highly hydrophilic magnetic nanoparticles have been molecularly designed. For the first time, the application of highly water-soluble magnetic nanoparticles as novel draw solutes in forward osmosis (FO) was systematically investigated. Magnetic nanoparticles functionalized by various groups were synthesized to explore the correlation between the surface chemistry of magnetic nanoparticles and the achieved osmolality. We verified that magnetic nanoparticles capped with polyacrylic acid can yield the highest driving force and subsequently highest water flux among others. The used magnetic nanoparticles can be captured by the magnetic field and recycled back into the stream as draw solutes in the FO process. In addition, magnetic nanoparticles of different diameters were also synthesized to study the effect of particles size on FO performance. We demonstrate that the engineering of surface hydrophilicity and magnetic nanoparticle size is crucial in the application of nanoparticles as draw solutes in FO. It is believed that magnetic nanoparticles will soon be extensively used in this area. © 2010 American Chemical Society.

  20. Concentrations of Water-Soluble Vitamins in Blood and Urinary Excretion in Patients with Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    Hiromi Iwakawa

    2016-01-01

    Full Text Available We examined the concentrations of water-soluble vitamins in blood and urinary excretion of 22 patients with type 2 diabetes mellitus (type 2DM and 20 healthy control participants. Macronutrient and vitamin intakes of type 2DM subjects were measured using a weighed food record method. Control participants consumed a semipurified diet for eight days. Multiple linear regression models were used to determine whether significant differences existed in vitamin concentrations in blood independent of age, sex, and other confounding factors. Concentrations of vitamins B2, B6, C, niacin, and folate in blood were significantly lower in type 2DM subjects than in controls, independent of confounding factors. Renal clearances of vitamins B6, C, niacin, and folate were significantly higher in type 2DM subjects than in controls. In conclusion, concentrations of vitamins B2, B6, C, niacin, and folate in blood were significantly lower in type 2DM subjects than in controls, independent of confounding factors; based on the evidence of increased urinary clearance of these vitamins, the lower levels were likely due to impaired reabsorption processes.

  1. Synthesis and photophysicochemical studies of a water soluble conjugate between folic acid and zinc tetraaminophthalocyanine

    International Nuclear Information System (INIS)

    Khoza, Phindile; Antunes, Edith; Chen, Ji-Yao; Nyokong, Tebello

    2013-01-01

    This work reports on the synthesis of zinc tetraaminophthalocyanine (ZnTAPc) functionalized with folic acid (FA), forming ZnTAPcFA. The conjugate between FA and ZnTAPc was soluble in water whereas ZnTAPc alone is not. The structure of ZnTAPcFA conjugate was elucidated by 1 H NMR, MALDI-TOF mass and FTIR spectra. Photophysical and photochemical studies of ZnTAPcFA were conducted in DMSO. The increase in fluorescence quantum yield of the conjugate was accompanied by a decrease in the triplet and singlet oxygen quantum yields. The changes in triplet quantum and singlet oxygen quantum yields were marginal when ZnTAPc was simply mixed with FA without a chemical bond. - Highlights: ► A conjugate between folic acid and a zinc tetraaminophthalocyanine was formed. ► The conjugate is water soluble even though the phthalocyanine alone is not. ► The fluorescence quantum yield of the conjugate was enhanced compared to the phthalocyanine alone. ► Triplet quantum yields decreased for the conjugate

  2. RP-HPLC determination of water-soluble vitamins in honey.

    Science.gov (United States)

    Ciulu, Marco; Solinas, Silvia; Floris, Ignazio; Panzanelli, Angelo; Pilo, Maria I; Piu, Paola C; Spano, Nadia; Sanna, Gavino

    2011-01-15

    The assessment and validation of reliable analytical methods for the determination of vitamins in sugar-based matrices (e.g. honey) are still scarcely explored fields of research. This study proposes and fully validates a simple and fast RP-HPLC method for the simultaneous determination of five water-soluble vitamins (vitamin B(2), riboflavin; vitamin B(3), nicotinic acid; vitamin B(5), pantothenic acid; vitamin B(9), folic acid; and vitamin C, ascorbic acid) in honey. The method provides low detection and quantification limits, very good linearity in a large concentration interval, very good precision, and the absence of any bias. It has been successfully applied to 28 honey samples (mainly from Sardinia, Italy) of 12 different botanical origins. While the overall amount of the analytes in the samples is quite low (always below 40 mg kg(-1)), we have observed a marked dependence of some of their concentrations (i.e. vitamin B(3) and vitamin B(5)) and the botanical origin of the honey. This insight might lead to important characterization features for this food item. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Selectivity differences of water-soluble vitamins separated on hydrophilic interaction stationary phases.

    Science.gov (United States)

    Yang, Yuanzhong; Boysen, Reinhard I; Hearn, Milton T W

    2013-06-01

    In this study, the retention behavior and selectivity differences of water-soluble vitamins were evaluated with three types of polar stationary phases (i.e. an underivatized silica phase, an amide phase, and an amino phase) operated in the hydrophilic interaction chromatographic mode with ESI mass spectrometric detection. The effects of mobile phase composition, including buffer pH and concentration, on the retention and selectivity of the vitamins were investigated. In all stationary phases, the neutral or weakly charged vitamins exhibited very weak retention under each of the pH conditions, while the acidic and more basic vitamins showed diverse retention behaviors. With the underivatized silica phase, increasing the salt concentration of the mobile phase resulted in enhanced retention of the acidic vitamins, but decreased retention of the basic vitamins. These observations thus signify the involvement of secondary mechanisms, such as electrostatic interaction in the retention of these analytes. Under optimized conditions, a baseline separation of all vitamins was achieved with excellent peak efficiency. In addition, the effects of water content in the sample on retention and peak efficiency were examined, with sample stacking effects observed when the injected sample contained a high amount of water. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Chemometric methods for the simultaneous determination of some water-soluble vitamins.

    Science.gov (United States)

    Mohamed, Abdel-Maaboud I; Mohamed, Horria A; Mohamed, Niveen A; El-Zahery, Marwa R

    2011-01-01

    Two spectrophotometric methods, derivative and multivariate methods, were applied for the determination of binary, ternary, and quaternary mixtures of the water-soluble vitamins thiamine HCI (I), pyridoxine HCI (II), riboflavin (III), and cyanocobalamin (IV). The first method is divided into first derivative and first derivative of ratio spectra methods, and the second into classical least squares and principal components regression methods. Both methods are based on spectrophotometric measurements of the studied vitamins in 0.1 M HCl solution in the range of 200-500 nm for all components. The linear calibration curves were obtained from 2.5-90 microg/mL, and the correlation coefficients ranged from 0.9991 to 0.9999. These methods were applied for the analysis of the following mixtures: (I) and (II); (I), (II), and (III); (I), (II), and (IV); and (I), (II), (III), and (IV). The described methods were successfully applied for the determination of vitamin combinations in synthetic mixtures and dosage forms from different manufacturers. The recovery ranged from 96.1 +/- 1.2 to 101.2 +/- 1.0% for derivative methods and 97.0 +/- 0.5 to 101.9 +/- 1.3% for multivariate methods. The results of the developed methods were compared with those of reported methods, and gave good accuracy and precision.

  5. Concentrations of Water-Soluble Vitamins in Blood and Urinary Excretion in Patients with Diabetes Mellitus.

    Science.gov (United States)

    Iwakawa, Hiromi; Nakamura, Yasuyuki; Fukui, Tomiho; Fukuwatari, Tsutomu; Ugi, Satoshi; Maegawa, Hiroshi; Doi, Yukio; Shibata, Katsumi

    2016-01-01

    We examined the concentrations of water-soluble vitamins in blood and urinary excretion of 22 patients with type 2 diabetes mellitus (type 2DM) and 20 healthy control participants. Macronutrient and vitamin intakes of type 2DM subjects were measured using a weighed food record method. Control participants consumed a semipurified diet for eight days. Multiple linear regression models were used to determine whether significant differences existed in vitamin concentrations in blood independent of age, sex, and other confounding factors. Concentrations of vitamins B2, B6, C, niacin, and folate in blood were significantly lower in type 2DM subjects than in controls, independent of confounding factors. Renal clearances of vitamins B6, C, niacin, and folate were significantly higher in type 2DM subjects than in controls. In conclusion, concentrations of vitamins B2, B6, C, niacin, and folate in blood were significantly lower in type 2DM subjects than in controls, independent of confounding factors; based on the evidence of increased urinary clearance of these vitamins, the lower levels were likely due to impaired reabsorption processes.

  6. Simultaneous determination of eight water-soluble vitamins in supplemented foods by liquid chromatography.

    Science.gov (United States)

    Zafra-Gómez, Alberto; Garballo, Antonio; Morales, Juan C; García-Ayuso, Luis E

    2006-06-28

    A fast, simple, and reliable method for the isolation and determination of the vitamins thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, folic acid, cyanocobalamin, and ascorbic acid in food samples is proposed. The most relevant advantages of the proposed method are the simultaneous determination of the eight more common vitamins in enriched food products and a reduction of the time required for quantitative extraction, because the method consists merely of the addition of a precipitation solution and centrifugation of the sample. Furthermore, this method saves a substantial amount of reagents as compared with official methods, and minimal sample manipulation is achieved due to the few steps required. The chromatographic separation is carried out on a reverse phase C18 column, and the vitamins are detected at different wavelengths by either fluorescence or UV-visible detection. The proposed method was applied to the determination of water-soluble vitamins in supplemented milk, infant nutrition products, and milk powder certified reference material (CRM 421, BCR) with recoveries ranging from 90 to 100%.

  7. Influence of blood donation on levels of water-soluble vitamins.

    Science.gov (United States)

    Kalus, U; Pruss, A; Wodarra, J; Kiesewetter, H; Salama, A; Radtke, H

    2008-12-01

    Iron depletion is a well-known side effect of blood donation. Research evidence also suggests an increasing prevalence of vitamin deficiency in apparently healthy subjects, but there is little information regarding the relationship between blood donation and vitamin status. A total of 217 volunteers (80 first-time and 137 repeat blood donors) were consecutively enrolled in the study. All subjects completed self-administered medical history and food intake forms, which included questions regarding alcohol consumption and smoking as well as on vitamin supplement, iron and contraceptive use (females). Vitamin B6, folic acid, vitamin B12 and biotin levels were measured using standard techniques. The mean vitamin levels of first-time and repeat blood donors did not significantly differ. Vitamin deficiencies occurred in both first-time and repeat blood donors but not on vitamin supplements. Vitamin status was affected by alcohol, nicotine and contraceptives. Blood donation does not decrease the level of water-soluble vitamins. Vitamin deficiencies occur in apparently healthy first-time as well as in repeat blood donors and can be prevented by vitamin supplementation.

  8. Nutrient transport in the mammary gland: calcium, trace minerals and water soluble vitamins.

    Science.gov (United States)

    Montalbetti, Nicolas; Dalghi, Marianela G; Albrecht, Christiane; Hediger, Matthias A

    2014-03-01

    Milk nutrients are secreted by epithelial cells in the alveoli of the mammary gland by several complex and highly coordinated systems. Many of these nutrients are transported from the blood to the milk via transcellular pathways that involve the concerted activity of transport proteins on the apical and basolateral membranes of mammary epithelial cells. In this review, we focus on transport mechanisms that contribute to the secretion of calcium, trace minerals and water soluble vitamins into milk with particular focus on the role of transporters of the SLC series as well as calcium transport proteins (ion channels and pumps). Numerous members of the SLC family are involved in the regulation of essential nutrients in the milk, such as the divalent metal transporter-1 (SLC11A2), ferroportin-1 (SLC40A1) and the copper transporter CTR1 (SLC31A1). A deeper understanding of the physiology and pathophysiology of these transporters will be of great value for drug discovery and treatment of breast diseases.

  9. Debinding behaviour of a water soluble PEG/PMMA binder for Ti metal injection moulding

    International Nuclear Information System (INIS)

    Chen, Gang; Cao, Peng; Wen, Guian; Edmonds, Neil

    2013-01-01

    Polyethylene glycol (PEG) has been becoming a common component in the design of water soluble binder systems for metal injection moulding. Similar to solvent debinding, PEG can be leached out by water and the mechanism of debinding was proposed in the literature with somehow misleading information about the debinding mechanism, particularly about the formation of PEG gel. This work investigates the debinding behaviours of a PEG-based binder in titanium compacts. Titanium powder is formulated with PEG, poly(methyl methacrylate) (PMMA) and stearic acid (SA) to formulate titanium feedstock. To determine the debinding kinetics, the PEG removal percentages are measured at three different temperatures and for various specimen thicknesses. A mathematic model based on diffusion-controlled debinding process is established. The evolution of porous microstructure during the water debinding process is observed using scanning electron microscopy. Based on these observations, a water debinding mechanism for titanium alloy compacts formulated with PEG-based binders is proposed. - Highlights: ► The water-debinding behaviours of the PEG binder system were investigated. ► PEG dissolution and transportation, and the pore structure development. ► A water debinding mechanism of PEG-based binders is proposed. ► Incorrect explanation of PEG gelling in the literature is corrected. ► Correction/modification made as per the reviewers' comments and suggestions

  10. Distinction of water-soluble constituents between natural and cultured Cordyceps by capillary electrophoresis.

    Science.gov (United States)

    Li, S P; Song, Z H; Dong, T T X; Ji, Z N; Lo, C K; Zhu, S Q; Tsim, K W K

    2004-11-01

    Cordyceps is an expensive traditional Chinese medicine, which has anti-tumor activity and significant effects on the immune system. In Southeast Asia, Cordyceps is commonly sold in capsule form as a health food product. Most of these products are derived from cultured Cordyceps mycelia. Because of the price difference, some manufacturers claim their products are from natural Cordyceps. In order to distinguish among various types of Cordyceps in the market, the profiles of water-soluble constituents derived from different sources of Cordyceps were determined by capillary electrophoresis (CE). Both natural and cultured Cordyceps showed three peak clusters migrated at 5-7, 9-11 and 12-13 min, and the height and resolution of these peak clusters were rather distinct. Peak cluster at 9-11 min was identified as adenosine, guanosine and uridine, and shared a similarity between natural and cultured products. In contrast, the peak cluster at 5-7 min was characteristic of natural Cordyceps, regardless of hosts and sources. By using the peak characteristics of CE profiles of different Cordyceps samples, hierarchical clustering analysis was performed. The result shows that those samples of natural Cordyceps were grouped together distinct from the cultured and commercial products. Thus, the CE profiles could serve as fingerprints for the quality control of Cordyceps.

  11. Rapid planar chromatographic analysis of 25 water-soluble dyes used as food additives.

    Science.gov (United States)

    Morlock, Gertrud E; Oellig, Claudia

    2009-01-01

    A rapid planar chromatographic method for identification and quantification of 25 water-soluble dyes in food was developed. In a horizontal developing chamber, the chromatographic separation on silica gel 60F254 high-performance thin-layer chromatography plates took 12 min for 40 runs in parallel, using 8 mL ethyl acetate-methanol-water-acetic acid (65 + 23 + 11 + 1, v/v/v/v) mobile phase up to a migration distance of 50 mm. However, the total analysis time, inclusive of application and evaluation, took 60 min for 40 runs. Thus, the overall time/run can be calculated as 1.5 min with a solvent consumption of 200 microL. A sample throughput of 1000 runs/8 h day can be reached by switching between the working stations (application, development, and evaluation) in a 20 min interval, which triples the analysis throughput. Densitometry was performed by absorption measurement using the multiwavelength scan mode in the UV and visible ranges. Repeatabilities [relative standard deviation (RSD), 4 determinations] at the first or second calibration level showed precisions of mostly or = 0.9987) and RSD values ( or = 0.9996). If necessary for confirmation, online mass spectra were recorded within a minute.

  12. Detecting the Water-soluble Chloride Distribution of Cement Paste in a High-precision Way.

    Science.gov (United States)

    Chang, Honglei; Mu, Song

    2017-11-21

    To improve the accuracy of the chloride distribution along the depth of cement paste under cyclic wet-dry conditions, a new method is proposed to obtain a high-precision chloride profile. Firstly, paste specimens are molded, cured, and exposed to cyclic wet-dry conditions. Then, powder samples at different specimen depths are grinded when the exposure age is reached. Finally, the water-soluble chloride content is detected using a silver nitrate titration method, and chloride profiles are plotted. The key to improving the accuracy of the chloride distribution along the depth is to exclude the error in the powderization, which is the most critical step for testing the distribution of chloride. Based on the above concept, the grinding method in this protocol can be used to grind powder samples automatically layer by layer from the surface inward, and it should be noted that a very thin grinding thickness (less than 0.5 mm) with a minimum error less than 0.04 mm can be obtained. The chloride profile obtained by this method better reflects the chloride distribution in specimens, which helps researchers to capture the distribution features that are often overlooked. Furthermore, this method can be applied to studies in the field of cement-based materials, which require high chloride distribution accuracy.

  13. Reduction reactions of water soluble cyano-cobalt(III)-porphyrins: Metal versus ligand centered processes

    International Nuclear Information System (INIS)

    Mosseri, S.; Neta, P.; Harriman, A.; Hambright, P.

    1990-01-01

    Reduction reactions of dicyano-cobalt(III)-porphyrins [potential in vivo cyanide scavenger drugs] were studied by radiolytic and electrochemical methods using the water soluble tetrakis(4-sulfonatophenyl)porphyrin (TPPS) and tetrakis(N-methyl-4-pyridyl)porphyrin (TMPyP). For [(CN)2CoIIITPPS]-, reduction occurs stepwise to the CoII, CoI, and finally to the phlorin anion. This behavior is similar to that of the cobalt porphyrins in the absence of cyanide, except that the cyanide ligand shifts the reduction potentials to much more negative values. On the other hand, under radiolytic conditions, [(CN)2CoIIITMPyP]- is reduced on the porphyrin macrocycle by one electron to give the CoIII pi-radical anion, which disproportionates into the initial complex and the two-electron ring reduced CoIII phlorin. The radical anion is also formed by intramolecular electron transfer subsequent to the reaction of CoIITMPyP and cyanide. The results are compared with the chemistry of Vitamin B-12

  14. Natural products phytotoxicity A bioassay suitable for small quantities of slightly water-soluble compounds.

    Science.gov (United States)

    Dornbos, D L; Spencer, G F

    1990-02-01

    A large variety of secondary metabolites that can inhibit germination and/or seedling growth are produced by plants in low quantities. The objective of this study was to develop a bioassay capable of reliably assessing reductions in germination percentage and seedling length of small-seeded plant species caused by exposure to minute quantities of these compounds. The germination and growth of alfalfa (Medicago saliva), annual ryegrass (Lolium multiflorum), and velvetleaf (Abutilon theophrasti) were evaluated against six known phytotoxins from five chemical classes; cinmethylin (a herbicidal cineole derivative) was selected as a comparison standard. Each phytotoxin, dissolved in a suitable organic solvent, was placed on water-agar in small tissue culture wells. After the solvent evaporated, imbibed seeds were placed on the agar; after three days, germination percentages and seedling lengths were measured. Compared to a commonly used filter paper procedure, this modified agar bioassay required smaller quantities of compound per seed for comparable bioassay results. This bioassay also readily permitted the measurement of seedling length, a more sensitive indicator of phytotoxicity than germination. Seedling length decreased sigmoidally as the toxin concentration increased logarithmically. Phytotoxicity was a function of both compound and plant species. Cinmethylin, a grass herbicide, reduced the length of annual ryegrass seedlings by 90-100%, whereas that of alfalfa and velvetleaf was inhibited slightly. The agar bioassay facilitated the rapid and reliable testing of slightly water-soluble compounds, requiring only minute quantities of each compound to give reproducible results.

  15. Spectroscopic studies on the interaction of a water-soluble cationic porphyrin with proteins

    Science.gov (United States)

    Ma, Hong-Min; Chen, Xin; Zhang, Nuo; Han, Yan-Yan; Wu, Dan; Du, Bin; Wei, Qin

    2009-04-01

    The interaction of a water-soluble cationic porphyrin, meso-tetrakis (4- N, N, N-trimethylanilinium) porphyrin (TMAP), with two proteins, bovine serum albumin (BSA) and human serum albumin (HSA), was studied by UV-vis absorption spectroscopy, fluorescence spectroscopy, fluorescence anisotropy and synchronous fluorescence spectroscopy at neutral aqueous solutions. Free base TMAP bound to proteins as monomers and no aggregation was observed. The binding of TMAP quenched the fluorescence of the protein. On the contrary, the fluorescence of TMAP was enhanced and the fluorescence anisotropy increased due to the binding. The direct static binding mechanism could account for the quenching by TMAP and the binding constants were calculated. TMAP showed a higher quenching efficiency and binding constant of HSA than BSA. The binding of TMAP had no obvious effect on the molecular conformation of the protein. There was only one binding site for TMAP and it was located on the surface of the protein molecule. Electrostatic force played an important role in the binding due to the opposite charges on porphyrin and the proteins.

  16. Organic compounds in hot-water-soluble fractions from water repellent soils

    Science.gov (United States)

    Atanassova, Irena; Doerr, Stefan

    2014-05-01

    Water repellency (WR) is a soil property providing hydrophobic protection and preventing rapid microbial decomposition of organic matter entering the soil with litter or plant residues. Global warming can cause changes in WR, thus influencing water storage and plant productivity. Here we assess two different approaches for analysis of organic compounds composition in hot water extracts from accelerated solvent extraction (ASE) of water repellent soils. Extracts were lyophilized, fractionated on SiO2 (sand) and SPE cartridge, and measured by GC/MS. Dominant compounds were aromatic acids, short chain dicarboxylic acids (C4-C9), sugars, short chain fatty acids (C8-C18), and esters of stearic and palmitic acids. Polar compounds (mainly sugars) were adsorbed on applying SPE clean-up procedure, while esters were highly abundant. In addition to the removal of polar compounds, hydrophobic esters and hydrocarbons (alkanes and alkenes particle wettability and C dynamics in soils. Key words: soil water repellency, hot water soluble carbon (HWSC), GC/MS, hydrophobic compounds

  17. Improved Extraction and Quality Characterization of Water-Soluble Polysaccharide from Gamma-Irradiated Lentinus edodes.

    Science.gov (United States)

    Akram, Kashif; Shahbaz, Hafiz Muhammad; Kim, Gui-Ran; Farooq, Umar; Kwon, Joong-Ho

    2017-02-01

    Gamma irradiation was applied to the improved extraction of water-soluble polysaccharides (WSPs) from dried Lentinus edodes. Irradiation provided a dose-dependent increase in extraction yield (0 kGy, 2.01%; 7.5 kGy, 4.03%; 15 kGy, 7.17%) and purity (0 kGy, 78.8%; 7.5 kGy, 83.1%; 15 kGy, 85.6%) of the WSPs from hot-water extraction. The effect of irradiation was evident in the degraded microstructures and reduced molecular weights of the WSPs. However, nuclear magnetic resonance, Fourier-transform infrared, and X-ray diffraction spectroscopic analyses provided comparable structures of WSPs from nonirradiated and irradiated samples. UV-visible spectra showed a dose-dependent decline in intensity, but an improvement in thermal properties of the WSPs from the irradiated mushroom samples was observed. © 2017 Institute of Food Technologists®.

  18. Renal Cell Toxicity of Water-Soluble Coal Extracts from the Gulf Coast

    Science.gov (United States)

    Ojeda, A. S.; Ford, S.; Ihnat, M.; Gallucci, R. M.; Philp, P. R.

    2017-12-01

    In the Gulf Coast, many rural residents rely on private well water for drinking, cooking, and other domestic needs. A large portion of this region contains lignite coal deposits within shallow aquifers that potentially leach organic matter into the water supply. It is proposed that the organic matter leached from low-rank coal deposits contributes to the development of kidney disease, however, little work has been done to investigate the toxicity of coal extracts. In this study, human kidney cells (HK-2) were exposed to water-soluble extracts of Gulf Coast Coals to assess toxicity. Cell viability was measured by direct counts of total and necrotic cells. A dose-response curve was used to generate IC50 values, and the extracts showed significant toxicity that ranged from 0.5% w/v to 3% w/v IC50. The most toxic extract was from Louisiana where coal-derived organic material has been previously linked to high incidents of renal pelvic cancer (RPC). Although the toxic threshold measured in this study is significantly higher than the concentration of organic matter in the groundwater, typically affected areas may consume contaminated water over a lifetime. It is possible that the cumulative toxic effects of coal-derived material contribute to the development of disease.

  19. Chemical properties and antioxidant activity of a water-soluble polysaccharide from Dendrobium officinale.

    Science.gov (United States)

    Luo, Qiu-Lian; Tang, Zhuan-Hui; Zhang, Xue-Feng; Zhong, Yong-Hong; Yao, Su-Zhi; Wang, Li-Sheng; Lin, Cui-Wu; Luo, Xuan

    2016-08-01

    In this report, a water-soluble polysaccharide was obtained from the dried stems of Dendrobium officinale Kimura et Migo by hot-water (70-75°C) extraction and 85% ethanol precipitation, and successively purification by DEAE-cellulose anion-exchange chromatography and gel-permeation chromatography. The D. officinale polysaccharide (DOP) has a molecular weight of 8500Da. Monosaccharide composition analysis reveals that DOP is composed of mannose, glucose, and arabinose with a trace of galacturonic acid in a molar ratio of 6.2:2.3:2.1:0.1. Periodate oxidation-smith degradation and 1D and 2D NMR spectroscopy analysis suggest the predominance of mannose and glucose, and it contains a 2-O-acetylglucomannan and (1→4)-linked-β-d-mannopyranosyl and (1→4)-linked-β-d-glucopyranosyl residues. Atomic force microscope shows that DOP mainly exists as rod-shaped chains, supporting high degrees of polymerization. The antioxidant activities of the polysaccharide in vitro assay indicate that DOP has good scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, higher scavenging activity of hydroxyl radical, and metal chelating activities. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Calcium carbonate growth in the presence of water soluble cellulose ethers

    International Nuclear Information System (INIS)

    Zhang Fengju; Yang Xinguo; Tian Fei

    2009-01-01

    Calcium carbonate precipitation was performed in the presence of methyl cellulose (MC) and two kinds of hydroxyethyl cellulose (HEC FD-10000, HEC FD-30000). The results demonstrated that the final product morphology and structure of CaCO 3 crystals are highly sensitive to the concentration of the cellulose ethers aqueous solution. By precisely controlling their concentrations, all these three cellulose ethers solutions have the ability of protecting metastable vaterite from thermodynamically transforming into stable calcite. The intermediate products investigation showed to some extent the phase transformation of calcium carbonate in its growing process from metastable vaterite to calcite and indicated that the calcium carbonate crystal growth in HEC solutions occurs through dissolution and reprecipitation process. Calcium carbonate growth in both presence of HEC and ethanol or Mg 2+ was also examined. This work demonstrates the potential of water soluble cellulose ethers in controlling biominerals crystallization and growth. The results are revelatory for biomineralization and fabricating new organic-inorganic hybrids based on cellulose derivatives.

  1. Hygroscopic behavior of atmospheric aerosols containing nitrate salts and water-soluble organic acids

    Directory of Open Access Journals (Sweden)

    B. Jing

    2018-04-01

    Full Text Available While nitrate salts have critical impacts on environmental effects of atmospheric aerosols, the effects of coexisting species on hygroscopicity of nitrate salts remain uncertain. The hygroscopic behaviors of nitrate salt aerosols (NH4NO3, NaNO3, Ca(NO32 and their internal mixtures with water-soluble organic acids were determined using a hygroscopicity tandem differential mobility analyzer (HTDMA. The nitrate salt ∕ organic acid mixed aerosols exhibit varying phase behavior and hygroscopic growth depending upon the type of components in the particles. Whereas pure nitrate salt particles show continuous water uptake with increasing relative humidity (RH, the deliquescence transition is still observed for ammonium nitrate particles internally mixed with organic acids such as oxalic acid and succinic acid with a high deliquescence point. The hygroscopicity of submicron aerosols containing sodium nitrate and an organic acid is also characterized by continuous growth, indicating that sodium nitrate tends to exist in a liquid-like state under dry conditions. It is observed that in contrast to the pure components, the water uptake is hindered at low and moderate RH for calcium nitrate particles containing malonic acid or phthalic acid, suggesting the potential effects of mass transfer limitation in highly viscous mixed systems. Our findings improve fundamental understanding of the phase behavior and water uptake of nitrate-salt-containing aerosols in the atmospheric environment.

  2. Water-soluble photopolymerizable chitosan hydrogels for biofabrication via two-photon polymerization.

    Science.gov (United States)

    Kufelt, Olga; El-Tamer, Ayman; Sehring, Camilla; Meißner, Marita; Schlie-Wolter, Sabrina; Chichkov, Boris N

    2015-05-01

    Fabrication of three-dimensional (3D) hydrogel microenvironments with predefined geometry and porosity can facilitate important requirements in tissue engineering and regenerative medicine. Chitosan (CH) is well known as a biocompatible hydrogel with prospective biological properties for biomedical aims. So far, microstructuring of this soft material presents a great limitation for its application as functional supporting material for guided tissue formation. Enabling photopolymerization, chemically modified CH can be applied for the biofabrication of reproducible 3D scaffolds using rapid prototyping techniques like two-photon polymerization (2PP) or others. The application of this technique allows precise serial fabrication of computer-designed microstructure geometries by scanning a femtosecond laser beam within a photosensitive material. This work explores a new synthesis of water-soluble photosensitive chitosan and the fabrication of well-defined microstructures from the generated materials. To modulate the mechanical and biochemical properties of the material, CH was combined and cross-linked with synthetic poly(ethylene glycol) diacrylate. For a biological adaption to the in vivo situation, CH was covalently crosslinked with a photosensitive modified vascular endothelial growth factor (VEGF). Performed in vitro studies reveal that modified CH is biocompatible. VEGF enhances CH bioactivity. Furthermore, a 3D CH scaffold can be successfully seeded with cells. Therefore, the established CH holds great promise for future applications in tissue engineering. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. Water soluble and metal-containing electron beam resist poly(sodium 4-styrenesulfonate)

    International Nuclear Information System (INIS)

    Abbas, Arwa Saud; Alqarni, Sondos; Shokouhi, Babak Baradaran; Yavuz, Mustafa; Cui, Bo

    2014-01-01

    Popular electron beam resists such as PMMA, ZEP and HSQ all use solvent or base solutions for processing, which may attack the sub-layers or substrate that are made out of organic semiconducting materials. In this study we show that water soluble poly(sodium 4-styrenesulfonate), or sodium PSS, can be used as a negative electron beam resist developed in water. Moreover, since PSS contains metal sodium, its dry etching resistance is much higher than PMMA. It is notable that sodium PSS’s sensitivity and contrast is still far inferior to organic resists such as PMMA, thus it is not suitable for patterning dense and high-resolution structures. Nevertheless, feature size down to 40 nm was achieved for sparse patterns. Lastly, using very low energy (here 2 keV) electron beam lithography and liftoff process using water only, patterning of metal layer on an organic conductive material P3HT was achieved. The metallization of an organic conducting material may find applications in organic semiconductor devices such as OLED. (paper)

  4. Nanostructured Polysulfone-Based Block Copolymer Membranes

    KAUST Repository

    Xie, Yihui

    2016-05-01

    The aim of this work is to fabricate nanostructured membranes from polysulfone-based block copolymers through self-assembly and non-solvent induced phase separation. Block copolymers containing polysulfone are novel materials for this purpose providing better mechanical and thermal stability to membranes than polystyrene-based copolymers, which have been exclusively used now. Firstly, we synthesized a triblock copolymer, poly(tert-butyl acrylate)-b-polsulfone-b-poly(tert-butyl acrylate) through polycondensation and reversible addition-fragmentation chain-transfer polymerization. The obtained membrane has a highly porous interconnected skin layer composed of elongated micelles with a flower-like arrangement, on top of the graded finger-like macrovoids. Membrane surface hydrolysis was carried out in a combination with metal complexation to obtain metal-chelated membranes. The copper-containing membrane showed improved antibacterial capability. Secondly, a poly(acrylic acid)-b-polysulfone-b-poly(acrylic acid) triblock copolymer obtained by hydrolyzing poly(tert-butyl acrylate)-b-polsulfone-b-poly(tert-butyl acrylate) formed a thin film with cylindrical poly(acrylic acid) microdomains in polysulfone matrix through thermal annealing. A phase inversion membrane was prepared from the same polymer via self-assembly and chelation-assisted non-solvent induced phase separation. The spherical micelles pre-formed in a selective solvent mixture packed into an ordered lattice in aid of metal-poly(acrylic acid) complexation. The space between micelles was filled with poly(acrylic acid)-metal complexes acting as potential water channels. The silver0 nanoparticle-decorated membrane was obtained by surface reduction, having three distinct layers with different particle sizes. Other amphiphilic copolymers containing polysulfone and water-soluble segments such as poly(ethylene glycol) and poly(N-isopropylacrylamide) were also synthesized through coupling reaction and copper0-mediated

  5. Identification of water-soluble heavy crude oil organic-acids, bases, and neutrals by electrospray ionization and field desorption ionization fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Stanford, Lateefah A; Kim, Sunghwan; Klein, Geoffrey C; Smith, Donald F; Rodgers, Ryan P; Marshall, Alan G

    2007-04-15

    We identify water-soluble (23 degrees C) crude oil NSO nonvolatile acidic, basic, and neutral crude oil hydrocarbons by negative-ion ESI and continuous flow FD FT-ICR MS at an average mass resolving power, m/deltam50% = 550,000. Of the 7000+ singly charged acidic species identified in South American crude oil, surprisingly, many are water-soluble, and much more so in pure water than in seawater. The truncated m/z distributions for water-soluble components exhibit preferential molecular weight, size, and heteroatom class influences on hydrocarbon solubility. Acidic water-soluble heteroatomic classes detected at >1% relative abundance include O, O2, O3, O4, OS, O2S, O3S, O4S, NO2, NO3, and NO4. Parent oil class abundance does not directly relate to abundance in the water-soluble fraction. Acidic oxygen-containing classes are most prevalent in the water-solubles, whereas acidic nitrogen-containing species are least soluble. In contrast to acidic nitrogen-containing heteroatomic classes, basic nitrogen classes are water-soluble. Water-soluble heteroatomic basic classes detected at >1% relative abundance include N, NO, NO2, NS, NS2, NOS, NO2S, N2, N2O, N2O2, OS, O2S, and O2S2.

  6. Deterioration of autoimmune condition associated with repeated injection of dextranomer/hyaluronic acid copolymer: A case report

    Directory of Open Access Journals (Sweden)

    Kazuto Suda

    2016-01-01

    Full Text Available A 6-year-old girl underwent ureterocystoneostomy (UCN because of left flank pain due to delayed onset of ureteral stenosis one and a half years after endoscopic dextranomer/hyaluronic acid copolymer (Deflux injection for the treatment of vesicoureteral reflux (VUR. Histopathological examination indicated chronic inflammation with abundant eosinophils characteristic of a reaction to Deflux. Several autoimmune diseases developed during the treatment for ureteral stenosis. First, 2 weeks prior to the onset of left flank pain, she was diagnosed as having systemic lupus erythematosus. Finally, she died of pulmonary hemorrhage due to thrombotic thrombocytopenic purpura 4 months after UCN. The fatal outcome in this case was suspected to be caused by autoimmune syndrome induced by adjuvants, which in this case was the hyaluronic acid polymer injected into the ureteric orifice for the treatment of VUR.

  7. Exploiting the biosynthetic machinery of Streptomyces pilosus to engineer a water-soluble zirconium(iv) chelator.

    Science.gov (United States)

    Richardson-Sanchez, Tomas; Tieu, William; Gotsbacher, Michael P; Telfer, Thomas J; Codd, Rachel

    2017-07-21

    The water solubility of a natural product-inspired octadentate hydroxamic acid chelator designed to coordinate Zr(iv)-89 has been improved by using a combined microbiological-chemical approach to engineer four ether oxygen atoms into the main-chain region of a methylene-containing analogue. First, an analogue of the trimeric hydroxamic acid desferrioxamine B (DFOB) that contained three main-chain ether oxygen atoms (DFOB-O 3 ) was generated from cultures of the native DFOB-producer Streptomyces pilosus supplemented with oxybis(ethanamine) (OBEA), which competed against the native 1,5-diaminopentane (DP) substrate during DFOB assembly. This precursor-directed biosynthesis (PDB) approach generated a suite of DFOB analogues containing one (DFOB-O 1 ), two (DFOB-O 2 ) or three (DFOB-O 3 ) ether oxygen atoms, with the latter produced as the major species. Log P measurements showed DFOB-O 3 was about 45 times more water soluble than DFOB. Second, a peptide coupling chain-extension reaction between DFOB-O 3 and the synthetic ether-containing endo-hydroxamic acid monomer 4-((2-(2-aminoethoxy)ethyl)(hydroxy)amino)-4-oxobutanoic acid (PBH-O 1 ) gave the water soluble tetrameric hydroxamic acid DFOB-O 3 -PBH-O 1 as an isostere of sparingly water soluble DFOB-PBH. The complex between DFOB-O 3 -PBH-O 1 and nat Zr(iv), examined as a surrogate measure of the radiolabelling procedure, analysed by LC-MS as the protonated adduct ([M + H] + , m/z obs = 855.2; m/z calc = 855.3), with supporting HRMS data. The use of a microbiological system to generate a water-soluble analogue of a natural product for downstream semi-synthetic chemistry is an attractive pathway for developing new drugs and imaging agents. The improved water solubility of DFOB-O 3 -PBH-O 1 could facilitate the synthesis and purification of downstream products, as part of the ongoing development of ligands optimised for Zr(iv)-89 immunological PET imaging.

  8. Profiling plasma extracellular vesicle by pluronic block-copolymer based enrichment method unveils features associated with breast cancer aggression, metastasis and invasion.

    Science.gov (United States)

    Zhong, Zhenyu; Rosenow, Matthew; Xiao, Nick; Spetzler, David

    2018-01-01

    Extracellular vesicle (EV)-based liquid biopsies have been proposed to be a readily obtainable biological substrate recently for both profiling and diagnostics purposes. Development of a fast and reliable preparation protocol to enrich such small particles could accelerate the discovery of informative, disease-related biomarkers. Though multiple EV enrichment protocols are available, in terms of efficiency, reproducibility and simplicity, precipitation-based methods are most amenable to studies with large numbers of subjects. However, the selectivity of the precipitation becomes critical. Here, we present a simple plasma EV enrichment protocol based on pluronic block copolymer. The enriched plasma EV was able to be verified by multiple platforms. Our results showed that the particles enriched from plasma by the copolymer were EV size vesicles with membrane structure; proteomic profiling showed that EV-related proteins were significantly enriched, while high-abundant plasma proteins were significantly reduced in comparison to other precipitation-based enrichment methods. Next-generation sequencing confirmed the existence of various RNA species that have been observed in EVs from previous studies. Small RNA sequencing showed enriched species compared to the corresponding plasma. Moreover, plasma EVs enriched from 20 advanced breast cancer patients and 20 age-matched non-cancer controls were profiled by semi-quantitative mass spectrometry. Protein features were further screened by EV proteomic profiles generated from four breast cancer cell lines, and then selected in cross-validation models. A total of 60 protein features that highly contributed in model prediction were identified. Interestingly, a large portion of these features were associated with breast cancer aggression, metastasis as well as invasion, consistent with the advanced clinical stage of the patients. In summary, we have developed a plasma EV enrichment method with improved precipitation selectivity

  9. Magnetic hyperthermia studies on water-soluble polyacrylic acid-coated cobalt ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Krishna Surendra, M. [Indian Institute of Technology Madras, Department of Physics, Nano Functional Materials Technology Centre, Materials Research Centre (India); Annapoorani, S. [Anna University of Technology, Department of Nanotechnology (India); Ansar, Ereath Beeran; Harikrishna Varma, P. R. [Sree Chitra Tirunal Institute for Medical Sciences and Technology, Bioceramics Laboratory (India); Ramachandra Rao, M. S., E-mail: msrrao@iitm.ac.in [Indian Institute of Technology Madras, Department of Physics, Nano Functional Materials Technology Centre, Materials Research Centre (India)

    2014-12-15

    We report on synthesis and hyperthermia studies in the water-soluble ferrofluid made of polyacrylic acid-coated cobalt ferrite (CoFe{sub 2}O{sub 4}) nanoparticles with different particle sizes. Magnetic nanoparticles were synthesized using co-precipitation method and particle size was varied as 6, 10, and 14 nm by varying the precursor to surfactant concentration. PAA surfactant bonding and surfactant thickness were studied by FTIR and thermogravimetric analysis. At room temperature, nanoparticles show superparamagnetism and saturation magnetization was found to vary from 33 to 44 emu/g with increase in the particle size from 6 to 14 nm, and this increase was attributed to the presence of a magnetic inert layer of 4 Å thick. Effect of particle size, concentration, and alternating magnetic field strength at 275 kHz on specific absorption rate were studied by preparing ferrofluids in deionized water at different concentrations. Ferrofluids at a concentration of 1.25 g/L, with 10 min of AMF exposure of strength ∼15.7 kA/m show stable temperatures ∼48, 58, and 68 °C with increase in the particle sizes 6, 10, and 14 nm. A maximum specific absorption rate of 251 W/g for ferrofluid with a particle size of 10 nm at 1.25 g/L, 15.7 kA/m, and 275 kHz was observed. Viability of L929 fibroblasts is measured by MTT assay cytotoxicity studies using the polyacrylic acid-coated CoFe{sub 2}O{sub 4} nanoparticles.

  10. The effect and fate of water-soluble carbon nanodots in maize (Zea mays L.).

    Science.gov (United States)

    Chen, Jing; Dou, Runzhi; Yang, Zhongzhou; Wang, Xiaoping; Mao, Chuanbin; Gao, Xiang; Wang, Li

    2016-08-01

    In this study, the toxicity of water-soluble carbon nanodots (C-dots) to maize (Zea mays L.) and their uptake and transport in plants were investigated. After exposed in sand matrix amended with 0-2000 mg/L C-dots for 4 weeks, we found that the phytotoxicity of C-dots was concentration-dependent. C-dots at 250 and 500 mg/L showed no toxicity to maize. However, 1000 and 2000 mg/L C-dots significantly reduced the fresh weight of root by 57% and 68%, and decreased the shoot fresh weight by 38% and 72%, respectively. Moreover, in maize roots, the exposure of C-dots at 2000 mg/L significantly increased the H2O2 content and lipid peroxidation (6.5 and 1.65 times higher, respectively), as well as, the antioxidant enzymes activities, up to 2, 1.5, 1.9 and 1.9 times higher for catalase, ascorbate peroxidase, guaiacol peroxidase and superoxide dismutase, respectively. On the other hand, C-dots were observed in detached root-cap cells, cortex and vascular bundle of roots and mesophyll cells of leaves through fluorescence microscopy analysis, suggesting that C-dots were absorbed and translocated systemically in maize. Remarkably, a certain amount of C-dots were excreted out from leaf blade. To our knowledge, this is the first study combined phenotypic observation with physiologic responses and bioaccumulation and translocation analysis of C-dots to investigate their effect and fate in maize.

  11. Biochemical responses in freshwater fish after exposure to water-soluble fraction of gasoline.

    Science.gov (United States)

    Bettim, Franciele Lima; Galvan, Gabrieli Limberger; Cestari, Marta Margarete; Yamamoto, Carlos Itsuo; de Assis, Helena Cristina Silva

    2016-02-01

    The water-soluble fraction of gasoline (WSFG) is a complex mixture of mono-polycyclic aromatic hydrocarbons. The study aimed to evaluate the effects of WSFG diluted 1.5% on freshwater fish. Astyanax altiparanae were exposed to the WSFG for 96 h, under a semi-static system, with renewal of 25% of the gasoline test solution every 24 h. In addition, a decay of the contamination (DC) was carried out. During DC, the fish was exposed to the WSFG for 8 d, followed by another 7 d with renewal of 25% of volume aquaria with clean water every 24 h. For depuration, fish were transferred to aquaria with clean water, and in addition, 25% of the water was replaced every 24 h. The liver and kidney biotransformation, antioxidant defenses and lipid peroxidation (LPO) levels were evaluated. In the liver, the WSFG 1.5% caused reduction of glutathione S-transferase (GST) after 96 h and DC. In the kidney, only in depuration an increased GST activity was observed, and after DC a higher LPO levels. An increase of the superoxide dismutase (SOD) activity occurred at 96 h in both tissues; however, in the liver was also observed during the depuration. In WSFG 96 h, the glutathione peroxidase (GPx) activity in the kidney increased. As biomarkers of neurotoxicity, the brain and muscle acetylcholinesterase activities were measured, but the WSFG 1.5% did not change them. Therefore, this study brought forth more data about WSFG effects on freshwater fish after lower concentrations exposure and a DC, simulating an environmental contamination. Copyright © 2015. Published by Elsevier Ltd.

  12. Nanostructured lipid carriers versus microemulsions for delivery of the poorly water-soluble drug luteolin.

    Science.gov (United States)

    Liu, Ying; Wang, Lan; Zhao, Yiqing; He, Man; Zhang, Xin; Niu, Mengmeng; Feng, Nianping

    2014-12-10

    Nanostructured lipid carriers and microemulsions effectively deliver poorly water-soluble drugs. However, few studies have investigated their ability and difference in improving drug bioavailability, especially the factors contributed to the difference. Thus, this study was aimed at investigating their efficiency in bioavailability enhancement based on studying two key processes that occur in NLC and ME during traverse along the intestinal tract: the solubilization process and the intestinal permeability process. The nanostructured lipid carriers and microemulsions had the same composition except that the former were prepared with solid lipids and the latter with liquid lipids; both were evaluated for particle size and zeta potential. Transmission electron microscopy, differential scanning calorimetry, and X-ray diffraction were performed to characterize their properties. Furthermore, in vitro drug release, in situ intestinal absorption, and in vitro lipolysis were studied. The bioavailability of luteolin delivered using nanostructured lipid carriers in rats was compared with that delivered using microemulsions and suspensions. The in vitro analysis revealed different release mechanisms for luteolin in nanostructured lipid carriers and microemulsions, although the in situ intestinal absorption was similar. The in vitro lipolysis data indicated that digestion speed and extent were higher for microemulsions than for nanostructured lipid carriers, and that more of the former partitioned to the aqueous phase. The in vivo bioavailability analysis in rats indicated that the oral absorption and bioavailability of luteolin delivered using nanostructured lipid carriers and microemulsions were higher than those of luteolin suspensions. Nanostructured lipid carriers and microemulsions improved luteolin's oral bioavailability in rats. The rapid lipid digestion and much more drug solubilized available for absorption in microemulsions may contribute to better absorption and

  13. Preparation of nanoparticles of poorly water-soluble antioxidant curcumin by antisolvent precipitation methods

    Science.gov (United States)

    Kakran, Mitali; Sahoo, Nanda Gopal; Tan, I.-Lin; Li, Lin

    2012-03-01

    The objective of this study was to enhance the solubility and dissolution rate of a poorly water-soluble antioxidant, curcumin, by fabricating its nanoparticles with two methods: antisolvent precipitation with a syringe pump (APSP) and evaporative precipitation of nanosuspension (EPN). For APSP, process parameters like flow rate, stirring speed, solvent to antisolvent (SAS) ratio, and drug concentration were investigated to obtain the smallest particle size. For EPN, factors like drug concentration and the SAS ratio were examined. The effects of these process parameters on the supersaturation, nucleation, and growth rate were studied and optimized to obtain the smallest particle size of curcumin by both the methods. The average particle size of the original drug was about 10-12 μm and it was decreased to a mean diameter of 330 nm for the APSP method and to 150 nm for the EPN method. Overall, decreasing the drug concentration or increasing the flow rate, stirring rate, and antisolvent amount resulted in smaller particle sizes. Differential scanning calorimetry studies suggested lower crystallinity of curcumin particles fabricated. The solubility and dissolution rates of the prepared curcumin particles were significantly higher than those the original curcumin. The antioxidant activity, studied by the DPPH free radical-scavenging assay, was greater for the curcumin nanoparticles than the original curcumin. This study demonstrated that both the methods can successfully prepare curcumin into submicro to nanoparticles. However, drug particles prepared by EPN were smaller than those by APSP and hence, showed the slightly better solubility, dissolution rate, and antioxidant activity than the latter.

  14. The cytotoxicity studies of water-soluble InP/ZnSe quantum dots

    International Nuclear Information System (INIS)

    Kiplagat, Ayabei; Sibuyi, Nicole R. S.; Onani, Martin O.; Meyer, Mervin; Madiehe, Abram M.

    2016-01-01

    Biomedical applications require nanocrystals with a narrow emission spectra and low toxicity. One major challenge of using quantum dots (QDs) in biomedical studies has been to synthesize them in large quantities while retaining desirable optical properties. To date, no research has been carried out to scale up the synthesis of InP/ZnSe nanocrystals. In this regard we synthesized InP/ZnSe nanocrystals using lower volumes and masses and scaled up the synthesis while retaining their molar ratios. The properties of the products obtained in small scale and scaled up syntheses were compared in regard to changes in particle size, emission wavelength and the trend of fluorescence of the aliquots. The particle size for the small scale reaction was determined to be 4.18 nm. When the synthesis was scaled up by a factor of 2, 4 and 6, the sizes were found to increase to 4.31, 4.13 and 4.37 nm, respectively. We also demonstrated the ability to tune the emission wavelength by sorting the particles in the crude product to different sizes. The size sorting process gave QDs with varied emission wavelengths and also narrow emission spectra. We further demonstrated a facile method for their water solubility as well as suitability for various biological applications. The toxicity of the synthesized InP/ZnSe nanocrystals was investigated. The cytotoxicity studies were carried out using two different types of non-cancerous human cell lines, namely KMST6 and MCF-12A, which clearly showed that the nanocrystals have low toxicity and are suitable for biological applications.

  15. Safety and toxicological evaluation of a novel, water-soluble undenatured type II collagen.

    Science.gov (United States)

    Yoshinari, Orie; Marone, Palma Ann; Moriyama, Hiroyoshi; Bagchi, Manashi; Shiojima, Yoshiaki

    2013-09-01

    This study was conducted to determine the broad-spectrum safety of a novel, water-soluble undenatured type II collagen (NEXT-II) derived from chicken sternum cartilage. The presence of epitope in NEXT-II was confirmed by using a commercial kit. The acute oral LD₅₀ of NEXT-II was found to be greater than 5000 mg/kg bw in rats, while the single-dose acute dermal LD₅₀ was greater than 2000 mg/kg bw. The primary dermal irritation index (PDII) of NEXT-II was found to be 1.8 and classified as slightly irritating to the skin. In primary eye irritation studies, the maximum mean total score (MMTS) of NEXT-II was observed to be 7.3 and classified as minimally irritating to the eye. Long-term safety studies were conducted in dogs over a period of 150 d, and no significant changes were observed in body weight, heart rate, respiration rate and blood chemistry. NEXT-II does not induce mutagenicity in the bacterial reverse mutation test in five Salmonella typhimurium strains either with or without metabolic activation. Furthermore, two experiments were conducted to assess the potential of NEXT-II to induce mutations with and without metabolic activation at the mouse lymphoma thymidine kinase locus using the cell line L5178Y. No biologically relevant increase of mutants was observed. Also, no dose-dependent toxicity was observed. Furthermore, colony sizing showed no clastogenic effects induced by NEXT-II under the experimental conditions. These studies demonstrated the broad spectrum of safety of NEXT-II.

  16. Enhancing the Solubility and Oral Bioavailability of Poorly Water-Soluble Drugs Using Monoolein Cubosomes.

    Science.gov (United States)

    Ali, Md Ashraf; Kataoka, Noriko; Ranneh, Abdul-Hackam; Iwao, Yasunori; Noguchi, Shuji; Oka, Toshihiko; Itai, Shigeru

    2017-01-01

    Monoolein cubosomes containing either spironolactone (SPI) or nifedipine (NI) were prepared using a high-pressure homogenization technique and characterized in terms of their solubility and oral bioavailability. The mean particle size, polydispersity index (PDI), zeta potential, solubility and encapsulation efficiency (EE) values of the SPI- and NI-loaded cubosomes were determined to be 90.4 nm, 0.187, -13.4 mV, 163 µg/mL and 90.2%, and 91.3 nm, 0.168, -12.8 mV, 189 µg/mL and 93.0%, respectively, which were almost identical to those of the blank cubosome. Small-angle X-ray scattering analyses confirmed that the SPI-loaded, NI-loaded and blank cubosomes existed in the cubic space group Im3̄m. The lattice parameters of the SPI- and NI-loaded cubosomes were 147.6 and 151.6 Å, respectively, making them almost identical to that of blank cubosome (151.0 Å). The in vitro release profiles of the SPI- and NI-loaded cubosomes showed that they released less than 5% of the drugs into various media over 12-48 h, indicating that most of the drug remained encapsulated within the cubic phase of their lipid bilayer. Furthermore, the in vivo pharmacokinetic results suggested that these cubosomes led to a considerable increase in the systemic oral bioavailability of the drugs compared with pure dispersions of the same materials. Notably, the stability results indicated that the mean particle size and PDI values of these cubosomes were stable for at least 4 weeks. Taken together, these results demonstrate that monoolein cubosomes represent promising drug carriers for enhancing the solubility and oral bioavailability of poorly water-soluble drugs.

  17. Correlations between water-soluble organic aerosol and water vapor: a synergistic effect from biogenic emissions?

    Science.gov (United States)

    Hennigan, Christopher J; Bergin, Michael H; Weber, Rodney J

    2008-12-15

    Ground-based measurements of meteorological parameters and water-soluble organic carbon in the gas(WSOCg) and particle (WSOCp) phases were carried out in Atlanta, Georgia, from May to September 2007. Fourteen separate events were observed throughout the summer in which WSOCp and water vapor concentrations were highly correlated (average WSOCp-water vapor r = 0.92); however, for the entire summer, no well-defined relationship existed between the two. The correlation events, which lasted on average 19 h, were characterized by a wide range of WSOCp and water vapor concentrations. Several hypotheses for the correlation are explored, including heterogeneous liquid phase SOA formation and the co-emission of biogenic VOCs and water vapor. The data provide supporting evidence for contributions from both and suggest the possibility of a synergistic effect between the co-emission of water vapor and VOCs from biogenic sources on SOA formation. Median WSOCp concentrations were also correlated with elemental carbon (EC), although this correlation extended over the entire summer. Despite the emission of water vapor from anthropogenic mobile sources and the WSOCp-EC correlation, mobile sources were not considered a potential cause for the WSOCp-water vapor correlations because of their low contribution to the water vapor budget. Meteorology could perhaps have influenced the WSOCp-EC correlation, but other factors are implicated as well. Overall, the results suggest that the temperature-dependent co-emission of water vapor through evapotranspiration and SOA precursor-VOCs by vegetation may be an important process contributing to SOA in some environments.

  18. Linear and nonlinear photophysics and bioimaging of an integrin-targeting water-soluble fluorenyl probe.

    Science.gov (United States)

    Morales, Alma R; Luchita, Gheorghe; Yanez, Ciceron O; Bondar, Mykhailo V; Przhonska, Olga V; Belfield, Kevin D

    2010-06-07

    Linear photophysical characterization and two-photon absorption (2PA) properties of a new water-soluble fluorene derivative, 3-(9-(2-(2-methoxyethoxy)ethyl)-2,7-bis{3-[2-(polyethyleneglycol-550-monomethylether-1-yl)]-4-(benzo[d]thiazol-2-yl)styryl}-9H-fluoren-9-yl)propanoic acid (1), were investigated in several organic solvents and water at room temperature. A comprehensive analysis of the steady-state absorption, emission and excitation anisotropy spectra revealed electronic structures of 1, including mutual orientation of the transition dipoles, relatively weak solvatochromic effects, high fluorescence quantum yield (approximately 0.5-1.0), and strong aggregation in water. The 2PA spectra of 1 were obtained in the 600-900 nm spectral range by two-photon induced fluorescence (2PF) and open aperture Z-scan methods using femtosecond laser sources. No discrete 2PA bands were apparent and values of the corresponding 2PA cross sections monotonically increased in the short wavelength range up to 3000 GM in organic solvents and approximately 6000 GM in aqueous solution, reflecting relatively high two-photon absorptivity. The 2PA efficiency of in water increased 2-3 times relative to aprotic solvents and can be explained by cooperative electronic effects of molecular aggregates of 1 produced in aqueous media. The carboxylic acid fluorenyl probe 1 was conjugated with the cyclic peptide RGDfK. Two-photon fluorescence microscopy (2PFM) imaging of U87MG cells (and MCF-7 as control), incubated with fluorene-RGD peptide conjugate 2, demonstrated high alpha(v)beta(3) integrin selectivity, making this probe particularly attractive for integrin imaging.

  19. Preparation of nanoparticles of poorly water-soluble antioxidant curcumin by antisolvent precipitation methods

    Energy Technology Data Exchange (ETDEWEB)

    Kakran, Mitali; Sahoo, Nanda Gopal; Tan, I-Lin; Li Lin, E-mail: mlli@ntu.edu.sg [Nanyang Technological University, School of Mechanical and Aerospace Engineering (Singapore)

    2012-03-15

    The objective of this study was to enhance the solubility and dissolution rate of a poorly water-soluble antioxidant, curcumin, by fabricating its nanoparticles with two methods: antisolvent precipitation with a syringe pump (APSP) and evaporative precipitation of nanosuspension (EPN). For APSP, process parameters like flow rate, stirring speed, solvent to antisolvent (SAS) ratio, and drug concentration were investigated to obtain the smallest particle size. For EPN, factors like drug concentration and the SAS ratio were examined. The effects of these process parameters on the supersaturation, nucleation, and growth rate were studied and optimized to obtain the smallest particle size of curcumin by both the methods. The average particle size of the original drug was about 10-12 {mu}m and it was decreased to a mean diameter of 330 nm for the APSP method and to 150 nm for the EPN method. Overall, decreasing the drug concentration or increasing the flow rate, stirring rate, and antisolvent amount resulted in smaller particle sizes. Differential scanning calorimetry studies suggested lower crystallinity of curcumin particles fabricated. The solubility and dissolution rates of the prepared curcumin particles were significantly higher than those the original curcumin. The antioxidant activity, studied by the DPPH free radical-scavenging assay, was greater for the curcumin nanoparticles than the original curcumin. This study demonstrated that both the methods can successfully prepare curcumin into submicro to nanoparticles. However, drug particles prepared by EPN were smaller than those by APSP and hence, showed the slightly better solubility, dissolution rate, and antioxidant activity than the latter.

  20. Preparation of nanoparticles of poorly water-soluble antioxidant curcumin by antisolvent precipitation methods

    International Nuclear Information System (INIS)

    Kakran, Mitali; Sahoo, Nanda Gopal; Tan, I-Lin; Li Lin

    2012-01-01

    The objective of this study was to enhance the solubility and dissolution rate of a poorly water-soluble antioxidant, curcumin, by fabricating its nanoparticles with two methods: antisolvent precipitation with a syringe pump (APSP) and evaporative precipitation of nanosuspension (EPN). For APSP, process parameters like flow rate, stirring speed, solvent to antisolvent (SAS) ratio, and drug concentration were investigated to obtain the smallest particle size. For EPN, factors like drug concentration and the SAS ratio were examined. The effects of these process parameters on the supersaturation, nucleation, and growth rate were studied and optimized to obtain the smallest particle size of curcumin by both the methods. The average particle size of the original drug was about 10–12 μm and it was decreased to a mean diameter of 330 nm for the APSP method and to 150 nm for the EPN method. Overall, decreasing the drug concentration or increasing the flow rate, stirring rate, and antisolvent amount resulted in smaller particle sizes. Differential scanning calorimetry studies suggested lower crystallinity of curcumin particles fabricated. The solubility and dissolution rates of the prepared curcumin particles were significantly higher than those the original curcumin. The antioxidant activity, studied by the DPPH free radical-scavenging assay, was greater for the curcumin nanoparticles than the original curcumin. This study demonstrated that both the methods can successfully prepare curcumin into submicro to nanoparticles. However, drug particles prepared by EPN were smaller than those by APSP and hence, showed the slightly better solubility, dissolution rate, and antioxidant activity than the latter.

  1. Effects of excess pantothenic acid administration on the other water-soluble vitamin metabolisms in rats.

    Science.gov (United States)

    Shibata, Katsumi; Takahashi, Chisato; Fukuwatari, Tsutomu; Sasaki, Ryuzo

    2005-12-01

    To acquire the data concerning the tolerable upper intake level which prevents health problems from an excessive intake of pantothenic acid, an animal experiment was done. Rats of the Wistar strain (male, 3 wk old) were fed on a diet which contains 0%, 0.0016% (control group), 1%, or 3% calcium pantothenate for 29 d. The amount of weight increase, the food intake, and the organ weights were measured, as well as the pantothenic acid contents in urine, the liver and blood. Moreover, to learn the influence of excessive pantothenic acid on other water-soluble vitamin metabolism, thiamin, riboflavin, a vitamin B6 catabolite, the niacin catabolites, and ascorbic acid in urine were measured. As for the 3% addition group, enlargement of the testis, diarrhea, and hair damage were observed, and the amount of weight increase and the food intake were less than those of the control group. However, abnormality was not seen in the 1% addition group. The amount of pantothenic acid in urine, the liver, and blood showed a high correlation with intake level of pantothenic acid. It was only for 4-pyridoxic acid, a vitamin B6 catabolite, in urine that a remarkable difference was observed against the control group. Moreover, the (2-Py+4-Py)/MNA excretion ratio for these metabolites of the nicotinamide also indicated a low value in the 3% pantothenic acid group. As for the calcium pantothenate, it was found that the 3% level in the diet was the lowest-observed-adverse-effect-level (LOAEL) and the 1% level was the no-observed-adverse-effect-level (NOAEL).

  2. Composition and Antioxidant Activity of Water-Soluble Polysaccharides from Tuber indicum

    Science.gov (United States)

    Luo, Qiang; Zhang, Jie; Yan, Liang; Tang, Yuanlin; Ding, Xiang; Yang, Zhirong

    2011-01-01

    Abstract Crude water-soluble Chinese truffle Tuber indicum polysaccharide (TIP) was extracted from the fruiting bodies with water and then successively purified by DEAE–cellulose 52 and Sephadex G-100 column chromatography, yielding two major polysaccharide fractions: TIP1-1 and TIP2-1. High-performance gel permeation chromatography analysis showed that the average molecular sizes of TIP1-1 and TIP2-1 were approximately 1.75×104 Da and 5.73×103 Da, respectively. Monosaccharide component analysis by gas chromatography indicated that TIP1-1 was composed of mannose, glucose, galactose, and rhamannose in the respective molar ratio of 3.93:1.24:0.75:1.26 and that TIP2-1 contained mannose, glucose, and arabinose in the respective molar ratio of 5.27:1.44:0.43. The antioxidant activity analyses revealed that TIP1-1 and TIP2-1 possessed considerable antioxidant activity. Compared with TIP1-1, which has a higher molecular weight and contains no uronic acid, TIP2-1 exhibited a protective effect on PC12 cells injured by H2O2 and a higher scavenging activity against free radicals. The relative effects of the lower molecular size, the presence of uronic acid, and the antioxidant activity of TIP2-1 appear to be significant. Accordingly, the Chinese truffle T. indicum might serve as an effective antioxidative healthcare food and source of natural antioxidants. PMID:21877953

  3. Structure and Antitumor and Immunomodulatory Activities of a Water-Soluble Polysaccharide from Dimocarpus longan Pulp

    Science.gov (United States)

    Meng, Fa-Yan; Ning, Yuan-Ling; Qi, Jia; He, Zhou; Jie, Jiang; Lin, Juan-Juan; Huang, Yan-Jun; Li, Fu-Sen; Li, Xue-Hua

    2014-01-01

    A new water-soluble polysaccharide (longan polysaccharide 1 (LP1)) was extracted and successfully purified from Dimocarpus longan pulp via diethylaminoethyl (DEAE)-cellulose anion-exchange and Sephacryl S-300 HR gel chromatography. The chemical structure was determined using Infrared (IR), gas chromatography (GC) and nuclear magnetic resonance (NMR) analysis. The results indicated that the molecular weight of the sample was 1.1 × 105 Da. Monosaccharide composition analysis revealed that LP1 was composed of Glc, GalA, Ara and Gal in a molar ratio of 5.39:1.04:0.74:0.21. Structural analysis indicated that LP1 consisted of a backbone of →4)-α-d-Glcp-(1→4)-α-d-GalpA-(1→4)-α-d-Glcp-(1→4)-β-d-Glcp-(1→ units with poly saccharide side chains composed of →2)-β-d-Fruf-(1→2)-l-sorbose-(1→ attached to the O-6 position of the α-d-Glcp residues. In vitro experiments indicated that LP1 had significantly high antitumor activity against SKOV3 and HO8910 tumor cells, with inhibition percentages of 40% and 50%, respectively. In addition, LP1 significantly stimulated the production of the cytokine interferon-γ (IFN-γ), increased the activity of murine macrophages and enhanced B- and T-lymphocyte proliferation. The results of this study demonstrate that LP1 has potential applications as a natural antitumor agent with immunomodulatory activity. PMID:24663085

  4. Toxicity evaluation of boron nitride nanospheres and water-soluble boron nitride in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Wang N

    2017-08-01

    Full Text Available Ning Wang,1 Hui Wang,2 Chengchun Tang,3 Shijun Lei,1 Wanqing Shen,1 Cong Wang,1 Guobin Wang,4 Zheng Wang,1,4 Lin Wang1,5 1Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, 2Department of Medical Genetics, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 3Boron Nitride Research Center, School of Materials Science and Engineering, Hebei University of Technology, Tianjin, 4Department of Gastrointestinal Surgery, 5Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China Abstract: Boron nitride (BN nanomaterials have been increasingly explored for potential biological applications. However, their toxicity remains poorly understood. Using Caenorhabditis elegans as a whole-animal model for toxicity analysis of two representative types of BN nanomaterials – BN nanospheres (BNNSs and highly water-soluble BN nanomaterial (named BN-800-2 – we found that BNNSs overall toxicity was less than soluble BN-800-2 with irregular shapes. The concentration thresholds for BNNSs and BN-800-2 were 100 µg·mL-1 and 10 µg·mL-1, respectively. Above this concentration, both delayed growth, decreased life span, reduced progeny, retarded locomotion behavior, and changed the expression of phenotype-related genes to various extents. BNNSs and BN-800-2 increased oxidative stress levels in C. elegans by promoting reactive oxygen species production. Our results further showed that oxidative stress response and MAPK signaling-related genes, such as GAS1, SOD2, SOD3, MEK1, and PMK1, might be key factors for reactive oxygen species production and toxic responses to BNNSs and BN-800-2 exposure. Together, our results suggest that when concentrations are lower than 10 µg·mL-1, BNNSs are more biocompatible than BN-800-2 and are potentially biocompatible material. Keywords: boron nitride nanomaterials, Caenorhabditis elegans, nanotoxicology

  5. Noncovalently-functionalized reduced graphene oxide sheets by water-soluble methyl green for supercapacitor application

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Xiaoying; Hu, Zhongai, E-mail: zhongai@nwnu.edu.cn; Hu, Haixiong; Qiang, Ruibin; Li, Li; Li, Zhimin; Yang, Yuying; Zhang, Ziyu; Wu, Hongying

    2015-10-15

    Graphical abstract: Electroactive methyl green (MG) is selected to functionalize reduced graphene oxide (RGO) through non-covalent modification and the composite achieves high specific capacitance, good rate capability and excellent long life cycle. - Highlights: • MG–RGO composites were firstly prepared through non-covalent modification. • The mass ratio in composites is a key for achieving high specific capacitance. • MG–RGO 5:4 exhibits the highest specific capacitance of 341 F g{sup −1}. • MG–RGO 5:4 shows excellent rate capability and long life cycle. - Abstract: In the present work, water-soluble electroactive methyl green (MG) has been used to non-covalently functionalize reduced graphene oxide (RGO) for enhancing supercapacitive performance. The microstructure, composition and morphology of MG–RGO composites are systematically characterized by UV–vis absorption, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The electrochemical performances are investigated by cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS). The fast redox reactions from MG could generate additional pseudocapacitance, which endows RGO higher capacitances. As a result, the MG–RGO composite (with the 5:4 mass ratio of MG:RGO) achieve a maximum value of 341 F g{sup −1} at 1 A g{sup −1} within the potential range from −0.25 to 0.75 V and provide a 180% enhancement in specific capacitance in comparison with pure RGO. Furthermore, excellent rate capability (72% capacitance retention from 1 A g{sup −1} to 20 A g{sup −1}) and long life cycle (12% capacitance decay after 5000 cycles) are achieved for the MG–RGO composite electrode.

  6. The use of low-osmolar water-soluble contrast in videofluoroscopic swallowing exams.

    Science.gov (United States)

    Harris, Julie A; Bartelt, Detlef; Campion, Molly; Gayler, Bob W; Jones, Bronwyn; Hayes, Andrea; Haynos, Judith; Herbick, Seanne; Kling, Therese; Lingaraj, Arpana; Singer, Michele; Starmer, Heather; Smith, Christine; Webster, Kim

    2013-12-01

    The selection of the contrast agent used during fluoroscopic exams is an important clinical decision. The purpose of this article is to document the usage of a nonionic, water-soluble contrast (iohexol) and barium contrast in adult patients undergoing fluoroscopic exams of the pharynx and/or esophagus and provide clinical indications for the use of each. For 1 year, data were collected on the use of iohexol and barium during fluoroscopic exams. The contrast agent used was selected by the speech language pathologist (SLP) or the radiologist based on the exam's indications. A total of 1,978 fluoroscopic exams were completed in the 12-month period of documentation. Of these exams, 60.6 % were completed for medical reasons and 39.4 % for surgical reasons. Fifty-five percent of the exams were performed jointly by a SLP and a radiologist and 45 % were performed by a radiologist alone. Aspiration was present in 22 % of the exams, vestibular penetration occurred in 38 %, extraluminal leakage of contrast was observed in 4.6 %, and both aspiration and leakage were seen in 1 % of the exams. In cases with aspiration, iohexol was used alone in 8 %, iohexol and barium were both used in 45 %, and barium was used alone in 47 %. In cases with extraluminal leakage, iohexol was used alone in 58 %, iohexol and barium were both used in 31 %, and barium was used alone in 11 %. No adverse effects were seen with the use of iohexol. When barium was used in cases of aspiration and extraluminal leakage, the amount of aspirated barium was small and the extraluminal barium in the instances of leakage was small. Iohexol is a useful screening contrast agent and can safely provide information, and its use reduces the risk of aspiration and the chance of leakage of large amounts of barium.

  7. Disproportionation of hydroxylamine by water-soluble iron(III) porphyrinate compounds.

    Science.gov (United States)

    Bari, Sara E; Amorebieta, Valentín T; Gutiérrez, María M; Olabe, José A; Doctorovich, Fabio

    2010-01-01

    The reactions of hydroxylamine (HA) with several water-soluble iron(III) porphyrinate compounds, namely iron(III) meso-tetrakis-(N-ethylpyridinium-2yl)-porphyrinate ([Fe(III)(TEPyP)](5+)), iron(III) meso-tetrakis-(4-sulphonatophenyl)-porphyrinate ([Fe(III)(TPPS)](3-)), and microperoxidase 11 ([Fe(III)(MP11)]) were studied for different [Fe(III)(Porph)]/[HA] ratios, under anaerobic conditions at neutral pH. Efficient catalytic processes leading to the disproportionation of HA by these iron(III) porphyrinates were evidenced for the first time. As a common feature, only N(2) and N(2)O were found as gaseous, nitrogen-containing oxidation products, while NH(3) was the unique reduced species detected. Different N(2)/N(2)O ratios obtained with these three porphyrinates strongly suggest distinctive mechanistic scenarios: while [Fe(III)(TEPyP)](5+) and [Fe(III)(MP11)] formed unknown steady-state porphyrinic intermediates in the presence of HA, [Fe(III)(TPPS)](3-) led to the well characterized soluble intermediate, [Fe(II)(TPPS)NO](4-). Free-radical formation was only evidenced for [Fe(III)(TEPyP)](5+), as a consequence of a metal centered reduction. We discuss the catalytic pathways of HA disproportionation on the basis of the distribution of gaseous products, free radicals formation, the nature of porphyrinic intermediates, the Fe(II)/Fe(III) redox potential, the coordinating capabilities of each complex, and the kinetic analysis. The absence of NO(2)(-) revealed either that no HAO-like activity was operative under our reaction conditions, or that NO(2)(-), if formed, was consumed in the reaction milieu.

  8. Sequential determination of fat- and water-soluble vitamins in green leafy vegetables during storage.

    Science.gov (United States)

    Santos, J; Mendiola, J A; Oliveira, M B P P; Ibáñez, E; Herrero, M

    2012-10-26

    The simultaneous analysis of fat- and water-soluble vitamins from foods is a difficult task considering the wide range of chemical structures involved. In this work, a new procedure based on a sequential extraction and analysis of both types of vitamins is presented. The procedure couples several simple extraction steps to LC-MS/MS and LC-DAD in order to quantify the free vitamins contents in fresh-cut vegetables before and after a 10-days storage period. The developed method allows the correct quantification of vitamins C, B(1), B(2), B(3), B(5), B(6), B(9), E and provitamin A in ready-to-eat green leafy vegetable products including green lettuce, ruby red lettuce, watercress, swiss chard, lamb's lettuce, spearmint, spinach, wild rocket, pea leaves, mizuna, garden cress and red mustard. Using this optimized methodology, low LOQs were attained for the analyzed vitamins in less than 100 min, including extraction and vitamin analysis using 2 optimized procedures; good repeatability and linearity was achieved for all vitamins studied, while recoveries ranged from 83% to 105%. The most abundant free vitamins found in leafy vegetable products were vitamin C, provitamin A and vitamin E. The richest sample on vitamin C and provitamin A was pea leaves (154 mg/g fresh weight and 14.4 mg/100g fresh weight, respectively), whereas lamb's lettuce was the vegetable with the highest content on vitamin E (3.1 mg/100 g fresh weight). Generally, some losses of vitamins were detected after storage, although the behavior of each vitamin varied strongly among samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Water-soluble vitamins in people with low glomerular filtration rate or on dialysis: a review.

    Science.gov (United States)

    Clase, Catherine M; Ki, Vincent; Holden, Rachel M

    2013-01-01

    People with low glomerular filtration rate and people on dialysis are spontaneously at risk for vitamin deficiency because of the potential for problems with decreased appetite and decreased sense of smell and taste, leading to decreased intake, and because decreased energy or decreased cognitive ability results in difficulties in shopping and cooking. Imposed dietary restrictions because of their renal dysfunction and because of comorbidities such as hypertension and diabetes exacerbate this problem. Finally, particularly for water-soluble vitamins, loss may occur into the dialysate. We did not identify any randomized trials of administering daily doses close to the recommended daily allowances of these vitamins. In people who are eating at all, deficiencies of B5 and B7 seem unlikely. It is unclear whether supplements of B2 and B3 are necessary. Because of dialyzability and documented evidence of insufficiency in dialysis patients, B1 supplementation is likely to be helpful. B6, B9, and B12 are implicated in the hyperhomocysteinemia observed in patients on dialysis. These vitamins have been studied in combinations, in high doses, with the hope of reducing cardiovascular outcomes. No reductions in patient-important outcomes were seen in adequately powered randomized trials. Because of their involvement in the homocysteine pathway, however, supplementation with lower doses, close to the recommended daily allowances, may be helpful. Vitamin C deficiency is common in patients on dialysis who are not taking supplements: low-dose supplements are warranted. Vitamins for dialysis patients contain most or all of the B vitamins and low-dose vitamin C. We are not aware of any medical reasons to choose one over another. © 2013. The Authors. Seminars in Dialysis published by Wiley Periodicals, Inc.

  10. The cytotoxicity studies of water-soluble InP/ZnSe quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Kiplagat, Ayabei [University of the Western Cape, Department of Chemistry, DST/Mintek Nanotechnology Innovation Centre (South Africa); Sibuyi, Nicole R. S. [University of the Western Cape, Department of Biotechnology, DST/Mintek Nanotechnology Innovation Centre (South Africa); Onani, Martin O., E-mail: monani@uwc.ac.za [University of the Western Cape, Department of Chemistry, DST/Mintek Nanotechnology Innovation Centre (South Africa); Meyer, Mervin; Madiehe, Abram M. [University of the Western Cape, Department of Biotechnology, DST/Mintek Nanotechnology Innovation Centre (South Africa)

    2016-06-15

    Biomedical applications require nanocrystals with a narrow emission spectra and low toxicity. One major challenge of using quantum dots (QDs) in biomedical studies has been to synthesize them in large quantities while retaining desirable optical properties. To date, no research has been carried out to scale up the synthesis of InP/ZnSe nanocrystals. In this regard we synthesized InP/ZnSe nanocrystals using lower volumes and masses and scaled up the synthesis while retaining their molar ratios. The properties of the products obtained in small scale and scaled up syntheses were compared in regard to changes in particle size, emission wavelength and the trend of fluorescence of the aliquots. The particle size for the small scale reaction was determined to be 4.18 nm. When the synthesis was scaled up by a factor of 2, 4 and 6, the sizes were found to increase to 4.31, 4.13 and 4.37 nm, respectively. We also demonstrated the ability to tune the emission wavelength by sorting the particles in the crude product to different sizes. The size sorting process gave QDs with varied emission wavelengths and also narrow emission spectra. We further demonstrated a facile method for their water solubility as well as suitability for various biological applications. The toxicity of the synthesized InP/ZnSe nanocrystals was investigated. The cytotoxicity studies were carried out using two different types of non-cancerous human cell lines, namely KMST6 and MCF-12A, which clearly showed that the nanocrystals have low toxicity and are suitable for biological applications.

  11. Water-soluble C60 fullerenes reduce manifestations of acute cholangitis in rats

    Science.gov (United States)

    Kuznietsova, H. M.; Lynchak, O. V.; Dziubenko, N. V.; Osetskyi, V. L.; Ogloblya, O. V.; Prylutskyy, Yu I.; Rybalchenko, V. K.; Ritter, U.; Scharff, P.

    2018-03-01

    Sclerosing cholangitis is the liver disease of uncertain etiology, extremely unfavorable prognosis and lack of effective medication therapy. Therefore, the effect of water-soluble biocompatible C60 fullerenes (C60FAS) on the liver functional state on rat acute-cholangitis model was aimed to be discovered. Acute cholangitis was simulated by single α-naphthyl isothiocyanate (ANIT, 100 mg/kg) per os administration; C60FAS (0.5 mg/kg) was administered either per os or intraperitoneally in 24 and 48 h after ANIT ingestion, and in 72 h the animals were sacrificed. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), the total and direct bilirubin, creatinine and urea in the blood serum were determined, and the liver morphological state was assessed. In animals experienced ANIT-induced acute cholangitis, the total and direct bilirubin, creatinine, ALT, AST, ALP and LDH 1.5-4-fold increase were observed, indicating cytolysis of hepatocytes, cholestasis, and renal dysfunction. The features of periductal fibrosis, biliary epithelium atrophy, and portal-portal linking septa formation were detected, confirming the sclerosing cholangitis development. C60FAS promoted to the normalization of direct and total bilirubin levels, the ALT activity and diminution of fibrotic features. In addition, C60FAS intraperitoneal administration also normalized the ALP activity, indicating the attenuation of disease symptoms. However, the AST activity and creatinine level remained unchanged, and the LDH activity even increased, manifesting the partial persistence of cholestasis and renal dysfunction. Thus, the therapeutic application of C60FAS promotes a partial protection of liver against cholangitis.

  12. Silicon containing copolymers

    CERN Document Server

    Amiri, Sahar; Amiri, Sanam

    2014-01-01

    Silicones have unique properties including thermal oxidative stability, low temperature flow, high compressibility, low surface tension, hydrophobicity and electric properties. These special properties have encouraged the exploration of alternative synthetic routes of well defined controlled microstructures of silicone copolymers, the subject of this Springer Brief. The authors explore the synthesis and characterization of notable block copolymers. Recent advances in controlled radical polymerization techniques leading to the facile synthesis of well-defined silicon based thermo reversible block copolymers?are described along with atom transfer radical polymerization (ATRP), a technique utilized to develop well-defined functional thermo reversible block copolymers. The brief also focuses on Polyrotaxanes and their great potential as stimulus-responsive materials which produce poly (dimethyl siloxane) (PDMS) based thermo reversible block copolymers.

  13. Design of water-soluble, thiol-reactive polymers of controlled molecular weight: a novel multivalent scaffold

    Science.gov (United States)

    Carrillo, Alvaro; Gujraty, Kunal V.; Rai, Prakash R.; Kane, Ravi S.

    2005-07-01

    Multivalent molecules, i.e. scaffolds presenting multiple copies of a suitable ligand, constitute an emerging class of nanoscale therapeutics. We present a novel approach for the design of multivalent ligands, which allows the biofunctionalization of polymers with proteins or peptides in a controlled orientation. It consists of the synthesis of water-soluble, activated polymer scaffolds of controlled molecular weight, which can be biofunctionalized with various thiolated ligands in aqueous media under mild conditions. These polymers were synthesized by ring-opening metathesis polymerization (ROMP) and further modified to make them water-soluble. The incorporation of chloride groups activated the polymers to react with thiol-containing peptides or proteins, and the formation of multivalent ligands in aqueous media was demonstrated. This strategy represents a convenient route for synthesizing multivalent ligands of controlled dimensions and valency.

  14. Synthesis and optical properties of water soluble CdSe/CdS quantum dots for biological applications

    International Nuclear Information System (INIS)

    Chu, Viet Ha; Lien Vu, Thi Kim; Lien Nghiem, Thi Ha; Nhung Tran, Hong; Le, Tien Ha; Lam Vu, Dinh

    2012-01-01

    Water soluble CdSe/CdS quantum dots (QDs) have been synthesized directly in aqueous solution with sodium citrate as surfactant agent. The QDs are mono-dispersed in water and have strong luminescent emission intensity under excitation of ultraviolet light. The emission maxima of the QDs can be tuned in a wider range from 555 to 615 nm in water by changing synthesis conditions. The result of the synthesis of water-soluble CdSe and CdSe/CdS QDs shows the high quality of the QDs with the quite narrow luminescence emission band and photostability. The results show the strongest intensity of photoluminescence emission in media with pH value at about from 8–8.5, which are pH physiological environments. The luminescence intensity increases when the QDs are coated with a polyethylene glycol (PEG) or bovine serum albumin (BSA) protein layer, the lifetime also increases

  15. Water soluble nano-scale transient material germanium oxide for zero toxic waste based environmentally benign nano-manufacturing

    KAUST Repository

    Almuslem, A. S.

    2017-02-14

    In the recent past, with the advent of transient electronics for mostly implantable and secured electronic applications, the whole field effect transistor structure has been dissolved in a variety of chemicals. Here, we show simple water soluble nano-scale (sub-10 nm) germanium oxide (GeO) as the dissolvable component to remove the functional structures of metal oxide semiconductor devices and then reuse the expensive germanium substrate again for functional device fabrication. This way, in addition to transiency, we also show an environmentally friendly manufacturing process for a complementary metal oxide semiconductor (CMOS) technology. Every year, trillions of complementary metal oxide semiconductor (CMOS) electronics are manufactured and billions are disposed, which extend the harmful impact to our environment. Therefore, this is a key study to show a pragmatic approach for water soluble high performance electronics for environmentally friendly manufacturing and bioresorbable electronic applications.

  16. Synthesis of new water-soluble metal-binding polymers: Combinatorial chemistry approach. 1998 annual progress report

    International Nuclear Information System (INIS)

    Kurth, M.J.; Miller, R.B.; Sawan, S.; Smith, B.F.

    1998-01-01

    '(1) Develop rapid discovery and optimization approaches to new water-soluble chelating polymers for use in Polymer Filtration (PF) systems, and (2) evaluate the concept of using water and organic soluble polymers as new solid supports for combinatorial synthesis. Polymer Filtration (PF), which uses water-soluble metal-binding polymers to sequester metal ions in dilute solution with ultrafiltration (UF) to separate the polymers, is a new technology to selectively remove or recover hazardous and valuable metal ions. Future directions in PF must include rapid development, testing, and characterization of new metal-binding polymers. Thus, the authors are building upon and adapting the combinatorial chemistry approach developed for rapid molecule generation for the drug industry to the rapid development of new chelating polymers. The authors have focused on four areas including the development of: (1) synthetic procedures, (2) small ultrafiltration equipment compatible with organic- and aqueous-based combinatorial synthesis, (3) rapid assay techniques, and (4) polymer characterization techniques.'

  17. Application of ion chromatography to the determination of water-soluble inorganic and organic ions in atmospheric aerosols.

    Science.gov (United States)

    Yu, Xue-Chun; He, Ke-Bin; Ma, Yong-Liang; Yang, Fu-Mo; Duan, Feng-Kui; Zheng, Ai-Hua; Zhao, Cheng-Yi

    2004-01-01

    A simple, sensitive and convenient ion chromatography(IC) method was established for the simultaneous determination of twelve water-soluble inorganic anions(F- , Cl- , NO2(-), NO3(-), SO3(2-), SO4(2-) , PO4(3-)), and fifteen water-soluble organic ions(formate, acetate, MSA, oxalate, malonate, succinate, phthalates, etc.) in atmospheric aerosols. The linear concentrations ranged from 0.005 microg/m3 to 500 microg/m3 ( r = 0.999-0.9999). The relative standard deviation (RSD) were 0.43%-2.00% and the detection limits were from 2.7 ng/m3 to 88 ng/m3. The proposed method was successfully applied to the simultaneous determination of those inorganic ions and organic ions in PM2.5 of Beijing.

  18. Isotope dilution liquid chromatography - mass spectrometry methods for fat- and water-soluble vitamins in nutritional formulations.

    Science.gov (United States)

    Phinney, Karen W; Rimmer, Catherine A; Thomas, Jeanice Brown; Sander, Lane C; Sharpless, Katherine E; Wise, Stephen A

    2011-01-01

    Vitamins are essential to human health, and dietary supplements containing vitamins are widely used by individuals hoping to ensure they have adequate intake of these important nutrients. Measurement of vitamins in nutritional formulations is necessary to monitor regulatory compliance and in studies examining the nutrient intake of specific populations. Liquid chromatographic methods, primarily with UV absorbance detection, are well established for both fat- and water-soluble measurements, but they do have limitations for certain analytes and may suffer from a lack of specificity in complex matrices. Liquid chromatography-mass spectrometry (LC-MS) provides both sensitivity and specificity for the determination of vitamins in these matrices, and simultaneous analysis of multiple vitamins in a single analysis is often possible. In this work, LC-MS methods were developed for both fat- and water-soluble vitamins and applied to the measurement of these analytes in two NIST Standard Reference Materials. When possible, stable isotope labeled internal standards were employed for quantification.

  19. Efficiency of nitrophosphates of varying water solubility with respect to their nitrogen (15N) and phosphorus (32P) utilisation

    International Nuclear Information System (INIS)

    Motsara, M.R.; Leela Bhai, K.S.; Mev Singh; Datta, N.P.

    1975-01-01

    Nitrophosphates of different water soluble P superphosphate and super plus ammonium nitrate were compared by raising wheat as a test crop on alluvial soil of Delhi. Phosphorus was tagged with 32 P and the ammonical and nitrate nitrogen was alternately tagged with 15 N. With increasing the water-soluble P content in nitrophosphate, increasing amount of grain yield and higher uptake of total N and P were recorded. The percent phosphorus derived in the plant from the fertilizer and the percent phosphorus utilization was higher from the nitrophosphates of higher eater soluble P content. It was also higher under the application of superphosphate plus ammonium nitrate than superphosphate alone. A greater amount of ammonical nitrogen was utilized by the crop than nitrate form of nitrogen. (author)

  20. Drying Characteristics and Water-soluble Polysaccharides Evaluation of Kidney Shape Ganoderma lucidum Drying in Air Circulation System

    Science.gov (United States)

    Prasetyo, D. J.; Jatmiko, T. H.; Poeloengasih, C. D.; Kismurtono, M.

    2017-12-01

    In this project, drying kinetic of kidney shape Ganoderma lucidum fruiting body in air circulation system was studied. The drying experiments were conducted at 40, 50 and 60°C with air flow rate of 1.3 ms-1. Samples were weighted periodically until no change in sample weight was recorded, and then the samples were analyzed for its moisture content. Four different thin-layer mathematical models (Newton, Page, Two-term, Midilli) were used and compare to evaluate the drying curves of kidney shape G. lucidum. The water-soluble polysaccharides were evaluated in order to find the best drying temperature condition. The results indicates that Midilli model was the fittest model to describe the characteristic of kidney shape G. lucidum in the air circulation drying system and temperature of 50°C was the best drying condition to get highest value of water-soluble polysaccharides.

  1. High mobility organic field-effect transistor based on water-soluble deoxyribonucleic acid via spray coating

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wei; Han, Shijiao; Huang, Wei; Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

    2015-01-26

    High mobility organic field-effect transistors (OFETs) by inserting water-soluble deoxyribonucleic acid (DNA) buffer layer between electrodes and pentacene film through spray coating process were fabricated. Compared with the OFETs incorporated with DNA in the conventional organic solvents of ethanol and methanol: water mixture, the water-soluble DNA based OFET exhibited an over four folds enhancement of field-effect mobility from 0.035 to 0.153 cm{sup 2}/Vs. By characterizing the surface morphology and the crystalline structure of pentacene active layer through atomic force microscope and X-ray diffraction, it was found that the adoption of water solvent in DNA solution, which played a key role in enhancing the field-effect mobility, was ascribed to both the elimination of the irreversible organic solvent-induced bulk-like phase transition of pentacene film and the diminution of a majority of charge trapping at interfaces in OFETs.

  2. Two-Stage Crystallizer Design for High Loading of Poorly Water-Soluble Pharmaceuticals in Porous Silica Matrices

    OpenAIRE

    Leia Dwyer; Samir Kulkarni; Luzdary Ruelas; Allan Myerson

    2017-01-01

    While porous silica supports have been previously studied as carriers for nanocrystalline forms of poorly water-soluble active pharmaceutical ingredients (APIs), increasing the loading of API in these matrices is of great importance if these carriers are to be used in drug formulations. A dual-stage mixed-suspension, mixed-product removal (MSMPR) crystallizer was designed in which the poorly soluble API fenofibrate was loaded into the porous matrices of pore sizes 35 nm-300 nm in the first st...

  3. SOLUBILITY AND BIOAVAILABILITY ENHANCEMENT STRATEGIES FOR EFFECTIVE DELIVERY OF POORLY WATER SOLUBLE DRUGS BY NANO FORMULATIONS AND SOLID DISPERSIONS

    OpenAIRE

    Rayapolu Ranga Goud*, Gunnala Krishnaveni, Girija Prasad Patro

    2018-01-01

    For the ancient few years, there has been a substantial research done on diverse methodologies for poorly water soluble and lipophilic drugs. More in modern times voluminous molecules cannot be distributed due to low solubility. Now a day frequently, particulate vesicle systems such as nanoparticles, liposomes, microspheres, niosomes, pronisomes, ethosomes, and proliposomes have been used as drug carriers. Drug delivery designates the technique and methodology to conveying medications or drug...

  4. Cinnamon Bark, Water Soluble Cinnamon Extract, and Metformin as Initial Treatment for Type 2 Diabetes Mellitus: A Randomized, Controlled Trial

    Science.gov (United States)

    2016-12-14

    Cinnamon Extract, and Metformin as Initial Treatment for Type 2 Diabetes Mellitus : A Randomized, Controlled Trial. Paul Crawford, MD Clinical Investigation...Title: “Cinnamon Bark, Water-Soluble Cinnamon Extract, and Metformin as Initial Treatment for Type 2 Diabetes Mellitus : A Randomized, Controlled...as initial treatment for Type 2 diabetes mellitus : A randomized, controlled trial. IRB #: FWH20110004H Principal Investigator (PI) Rank / Civ

  5. The effect of different concentrations of water soluble azadirachtin (neem metabolite on Streptococcus mutans compared with chlorhexidine

    Directory of Open Access Journals (Sweden)

    Amit R Kankariya

    2016-01-01

    Full Text Available Despite advances in the development of anticaries chemotherapy, the newer agents are unable to control the initiation of dental caries. Research and development of natural antibacterial agents that are safe for the host as well as specific for oral pathogens is awaited. Neem tree extracts have been used for thousands of years for maintaining overall well-being. Chewing neem sticks in the morning is the most common indigenous method of cleaning the mouth in rural population. This has generated the interest of the dentists for the use of neem for controlling dental diseases. Aims: This study aims to evaluate the quantitative and qualitative effect of different concentrations of water soluble azadirachtin (neem metabolite on Streptococcus mutans (S. mutans against chlorhexidine. Materials and Methods: Plaque was collected from 30 children aged 8-12 years reporting to the Department of Pediatric and Preventive Dentistry, Bharti Vidyapeeth Dental College, Pune and transported to the laboratory. After incubation of the plates the inhibitory zones were noted and the diameter of the zone of inhibition was measured and recorded to check the inhibition of growth of S. mutans. For testing the bacterial survival, the biofilms were prepared and colony forming units (CFU was enumerated using a digital colony counter. Statistical Analysis Used: Two-way analysis of variance (ANOVA and Tukey′s test. Results: The results show that there was no statistically significant difference in the inhibition of S. mutans between 40% concentration of water soluble azadirachtin and chlorhexidine. Conclusions: This study concluded that 40% water soluble azadirachtin is as effective as 0.2% chlorhexidine mouthrinse in reducing the S. mutans count in dental plaque. Hence, a water soluble formulation of azadirachtin may provide the maximum benefit to mankind to prevent dental caries.

  6. The effect of different concentrations of water soluble azadirachtin (neem metabolite) on Streptococcus mutans compared with chlorhexidine.

    Science.gov (United States)

    Kankariya, Amit R; Patel, Alok R; Kunte, Sanket S

    2016-01-01

    Despite advances in the development of anticaries chemotherapy, the newer agents are unable to control the initiation of dental caries. Research and development of natural antibacterial agents that are safe for the host as well as specific for oral pathogens is awaited. Neem tree extracts have been used for thousands of years for maintaining overall well-being. Chewing neem sticks in the morning is the most common indigenous method of cleaning the mouth in rural population. This has generated the interest of the dentists for the use of neem for controlling dental diseases. This study aims to evaluate the quantitative and qualitative effect of different concentrations of water soluble azadirachtin (neem metabolite) on Streptococcus mutans (S. mutans) against chlorhexidine. Plaque was collected from 30 children aged 8-12 years reporting to the Department of Pediatric and Preventive Dentistry, Bharti Vidyapeeth Dental College, Pune and transported to the laboratory. After incubation of the plates the inhibitory zones were noted and the diameter of the zone of inhibition was measured and recorded to check the inhibition of growth of S. mutans. For testing the bacterial survival, the biofilms were prepared and colony forming units (CFU) was enumerated using a digital colony counter. Two-way analysis of variance (ANOVA) and Tukey's test. The results show that there was no statistically significant difference in the inhibition of S. mutans between 40% concentration of water soluble azadirachtin and chlorhexidine. This study concluded that 40% water soluble azadirachtin is as effective as 0.2% chlorhexidine mouthrinse in reducing the S. mutans count in dental plaque. Hence, a water soluble formulation of azadirachtin may provide the maximum benefit to mankind to prevent dental caries.

  7. Synthesis of new water-soluble metal-binding polymers: Combinatorial chemistry approach. 1997 mid-year progress report

    International Nuclear Information System (INIS)

    Smith, B.F.

    1997-01-01

    'The first objective of this research is to develop rapid discovery and optimization approaches to new water-soluble chelating polymers. A byproduct of the development approach will be the new, selective, and efficient metal-binding agents. The second objective is to evaluate the concept of using water and organic soluble polymers as new solid supports for combinatorial synthesis. The technology under development, Polymer Filtration (PF), is a technique to selectively remove or recover hazardous and valuable metal ions and radionuclides from various dilute aqueous streams. Not only can this technology be used to remediate contaminated soils and solid surfaces and treat aqueous wastes, it can also be incorporated into facilities as a pollution prevention and waste minimization technology. Polymer Filtration uses water-soluble metal-binding polymers to sequester metal ions in dilute solution. The water-soluble polymers have a sufficiently large molecular size that they can be separated and concentrated using commercial ultrafiltration technology. Water, small organic molecules, and unbound metals pass freely through the ultrafiltration membrane while concentrating the metal-binding polymer. The polymers can then be reused by changing the solution conditions to release the metal ions. The metal-ions are recovered in concentrated form for recycle or disposal using a diafiltration process. The water-soluble polymer can be recycled for further aqueous-stream processing. To advance Polymer Filtration technology to the selectivity levels required for DOE needs. fixture directions in Polymer Filtration must include rapid development, testing, and characterization of new metal-binding polymers. The development of new chelating molecules can be equated to the process of new drugs or new materials discovery. Thus, the authors want to build upon and adapt the combinatorial chemistry approaches developed for rapid molecule generation for the drug industry to the rapid

  8. Encapsulation of β-carotene within ferritin nanocages greatly increases its water-solubility and thermal stability.

    Science.gov (United States)

    Chen, Lingli; Bai, Guangling; Yang, Rui; Zang, Jiachen; Zhou, Ting; Zhao, Guanghua

    2014-04-15

    Carotenoids may play a number of potential health benefits for human. However, their use in food industry is limited mostly because of their poor water-solubility and low thermal stability. Ferritins are widely distributed in nature with a shell-like structure which offers a great opportunity to improve the water-solubility and thermal stability of the carotenoids by encapsulation. In this work, recombinant human H-chain ferritin (rHuHF) was prepared and used to encapsulate β-carotene, a typical compound among carotenoids, by taking advantage of the reversible dissociation and reassembly characteristic of apoferritin in different pH environments. Results from high-performance liquid chromatography (HPLC), UV/Vis spectroscopy and transmission electron microscope (TEM) indicated that β-carotene molecules were successfully encapsulated within protein cages with a β-carotene/protein molar ratio of 12.4-1. Upon such encapsulation, these β-carotene-containing apoferritin nanocomposites were water-soluble. Interestingly, the thermal stability of the β-carotene encapsulated within apoferritin nanocages was markedly improved as compared to free β-carotene. These new properties might be favourable to the utilisation of β-carotene in food industry. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. The optical and electrical properties of graphene oxide with water-soluble conjugated polymer composites by radiation.

    Science.gov (United States)

    Jungo, Seung Tae; Oh, Seung-Hwan; Kim, Hyun Bin; Jeun, Joon-Pyo; Lee, Bum-Jae; Kang, Phil-Hyun

    2013-11-01

    In order to overcome the difficulty of dispersion and low conductivity in composite containing graphene, graphene oxide (GO) has been used instead of neat graphene. And the GO treated by radiation, could give improved conductivity of the GO-containing polymer composite. In this study, fluorene based water-soluble conjugated polymer (WPF-6-oxy-F) was introduced in GO solution to investigate the change of optical and electrical properties through radiation process. UV-Vis absorption of irradiated WPF-6-oxy-F-GO composite was red shifted and I(D)/I(G) ratio of Raman spectra decreased. XPS analysis showed that C-N bonds was formed after the irradiation and confirmed the increased bonds between the GO and the water-soluble conjugated polymer matrix. From the AFM and XPS analysis, it was found that the water-soluble conjugated polymer matrix was stacked between the modified GO in the morphology of irradiated WPF-6-oxy-F-GO composite was increased after gamma ray irradiation up to 10(-2) S/cm.

  10. Towards improved solubility of poorly water-soluble drugs: cryogenic co-grinding of piroxicam with carrier polymers.

    Science.gov (United States)

    Penkina, Anna; Semjonov, Kristian; Hakola, Maija; Vuorinen, Sirpa; Repo, Timo; Yliruusi, Jouko; Aruväli, Jaan; Kogermann, Karin; Veski, Peep; Heinämäki, Jyrki

    2016-01-01

    Amorphous solid dispersions (SDs) open up exciting opportunities in formulating poorly water-soluble active pharmaceutical ingredients (APIs). In the present study, novel catalytic pretreated softwood cellulose (CPSC) and polyvinylpyrrolidone (PVP) were investigated as carrier polymers for preparing and stabilizing cryogenic co-ground SDs of poorly water-soluble piroxicam (PRX). CPSC was isolated from pine wood (Pinus sylvestris). Raman and Fourier transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) were used for characterizing the solid-state changes and drug-polymer interactions. High-resolution scanning electron microscope (SEM) was used to analyze the particle size and surface morphology of starting materials and final cryogenic co-ground SDs. In addition, the molecular aspects of drug-polymer interactions and stabilization mechanisms are presented. The results showed that the carrier polymer influenced both the degree of amorphization of PRX and stabilization against crystallization. The cryogenic co-ground SDs prepared from PVP showed an enhanced dissolution rate of PRX, while the corresponding SDs prepared from CPSC exhibited a clear sustained release behavior. In conclusion, cryogenic co-grinding provides a versatile method for preparing amorphous SDs of poorly water-soluble APIs. The solid-state stability and dissolution behavior of such co-ground SDs are to a great extent dependent on the carrier polymer used.

  11. Effects of excess biotin administration on the growth and urinary excretion of water-soluble vitamins in young rats.

    Science.gov (United States)

    Sawamura, Hiromi; Fukuwatari, Tsutomu; Shibata, Katsumi

    2007-12-01

    To determine the effects of excess biotin administration on growth and water-soluble vitamin metabolism, weaning rats were fed on a 20% casein diet containing 0.00002% biotin, or same diet with 0.04, 0.08, 0.10, 0.20, 0.50, 0.80 or 1.0% added biotin for 28 days. More than 0.08% biotin administration decreased the food intake and body weight gain compared with the levels in control rats. An accumulation of biotin in such tissues as the liver, brain and kidney increased in a dose-dependent manner, and the both bound and free biotin contents in the liver also increased in a dose-dependent manner. An excess administration of biotin did not affect the urinary excretion of other water-soluble vitamins, suggesting no effect on the metabolism of other water-soluble vitamins. The results of the food intake and body weight gain indicated that the lowest observed adverse effect level for young rats was 79.2 mg/kg body weight/day, while the no observed adverse effect level was 38.4 mg/kg/day. These results suggested immediately setting a tolerable upper intake level for biotin.

  12. Characterization and blood coagulation evaluation of the water-soluble chitooligosaccharides prepared by a facile fractionation method.

    Science.gov (United States)

    Lin, Chia-Wen; Lin, Jui-Che

    2003-01-01

    Water-soluble chitooligosaccharides have been reported to have specific biological activities. In this study, the chitosan samples with different degree of acetylation were used separately to prepare chitooligosaccharide (COS) and highly deacetylated chitooligosaccharide (HDCOS) through the nitrous acid depolymerization. Rather than using the conventional fractionation schemes commonly employed, such as dialysis and ultrafiltration which require a large amount of deionized water as well as a fair long dwell time, an unique fractionation scheme is explored to recover and desalt these nitrous-acid depolymerized chitosan with different molecular weights. This fractionation scheme is based on the differential solubility variation of depolymerized products within the aqueous solutions that contain various ratios of methanol. It was noted that chitosan with different molecular weight can be successfully recovered and fractionated with methanol added sequentially up to a volume of four times of original depolmerized product. In addition, chemical characterization of the fractionated water-soluble COS and HDCOS by 1H NMR spectroscopy and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) indicated that the chitosan depolymerization reaction is greatly influenced by the degree of acetylation of the parental chitosan reactant. Moreover, the modified whole blood clotting time assay and the platelet coagulation test suggested that the 1:2 fractionated water-soluble COS and HDCOS obtained are much less procoagulant than their parental chitosan compound and can be of use in biomedical applications in which blood coagulation is not desired.

  13. The effect of newer water-soluble contrast media on I-131 uptake by the thyroid gland

    International Nuclear Information System (INIS)

    Starinsky, R.; Horne, T.; Barr, J.; Ramot, Y.

    2006-01-01

    The aim of this study was to evaluate the effect of two water-soluble contrast media (nonionic and Dimer) on iodine uptake by the thyroid gland. Twenty-eight euthyroid patients (16 females and 12 males) were subjected to 24hrs radioiodine uptake (RAIU) studies following brain CT examinations using the above cited two water-soluble contrast media. Radioiodine uptake studies were done at one (Group-1), two (Group-2) and four (Group-3) weeks following performance of contrast enhanced CT scans. The effect of both contrast media on the thyroid uptake was found to be identical. The radio active iodine uptake (RAIU) was observed to be suppressed in 30% of patients in Group-1, 33% of patients in Group-2 and in none of the patients belonging to Group-3. On the basis of this pilot study on a limited number of patients it was concluded that dimer and non-ionic water soluble contrast media cause suppression of radio iodine uptake by the thyroid gland in a significant proportion of patients. It has also been observed that both contrast media have similar suppressive effects on radio iodine uptake by the thyroid gland. This effect is transient and does not persist beyond a period of four weeks following the administration of the contrast media. (author)

  14. Controlling the photochemical reaction of an azastilbene derivative in water using a water-soluble pillar[6]arene.

    Science.gov (United States)

    Xia, Danyu; Wang, Pi; Shi, Bingbing

    2017-09-20

    Photochemistry plays an important role in our lives. It has also been a common tool in the laboratory to construct complicated systems from small molecules. Supramolecular chemistry provides an opportunity to solve some of the problems in controlling photochemical reactions via non-covalent interactions. By using confining media and weak interactions between the medium and the reactant molecule, the excited state behavior of molecules has been successfully manipulated. Pillararenes, a new class of macrocyclic hosts, have rarely been used in the field of photochemical investigations, such as the controlling of photo-induced reactions. Herein, we explore a synthetic macrocyclic host, a water-soluble pillar[6]arene, as a controlling tool to manipulate the photo-induced reactions (hydration) in water. A host-guest system in water based on a water-soluble pillar[6]arene and an azastilbene derivative, (E)-4,4'-dimethyl-4,4'-diazoniastilbene diiodide, has been constructed. Then this water-soluble pillar[6]arene was successfully employed to control the photohydration of the azastilbene derivative in water as a "protective agent".

  15. Salinity impacts on water solubility and n-octanol/water partition coefficients of selected pesticides and oil constituents.

    Science.gov (United States)

    Saranjampour, Parichehr; Vebrosky, Emily N; Armbrust, Kevin L

    2017-09-01

    Salinity has been reported to influence the water solubility of organic chemicals entering marine ecosystems. However, limited data are available on salinity impacts for chemicals potentially entering seawater. Impacts on water solubility would correspondingly impact chemical sorption as well as overall bioavailability and exposure estimates used in the regulatory assessment. The pesticides atrazine, fipronil, bifenthrin, and cypermethrin, as well as the crude oil constituent dibenzothiophene together with 3 of its alkyl derivatives, all have different polarities and were selected as model compounds to demonstrate the impact of salinity on their solubility and partitioning behavior. The n-octanol/water partition coefficient (K OW ) was measured in both distilled-deionized water and artificial seawater (3.2%). All compounds had diminished solubility and increased K OW values in artificial seawater compared with distilled-deionized water. A linear correlation curve estimated salinity may increase the log K OW value by 2.6%/1 log unit increase in distilled water (R 2  = 0.97). Salinity appears to generally decrease the water solubility and increase the partitioning potential. Environmental fate estimates based on these parameters indicate elevated chemical sorption to sediment, overall bioavailability, and toxicity in artificial seawater. These dramatic differences suggest that salinity should be taken into account when exposure estimates are made for marine organisms. Environ Toxicol Chem 2017;36:2274-2280. © 2017 SETAC. © 2017 SETAC.

  16. Pressurized capillary electrochromatographic analysis of water-soluble vitamins by combining with on-line concentration technique.

    Science.gov (United States)

    Jia, Li; Liu, Yaling; Du, Yanyan; Xing, Da

    2007-06-22

    A pressurized capillary electrochromatography (pCEC) system was developed for the separation of water-soluble vitamins, in which UV absorbance was used as the detection method and a monolithic silica-ODS column as the separation column. The parameters (type and content of organic solvent in the mobile phase, type and concentration of electrolyte, pH of the electrolyte buffer, applied voltage and flow rate) affecting the separation resolution were evaluated. The combination of two on-line concentration techniques, namely, solvent gradient zone sharpening effect and field-enhanced sample stacking, was utilized to improve detection sensitivity, which proved to be beneficial to enhance the detection sensitivity by enabling the injection of large volumes of samples. Coupling electrokinetic injection with the on-line concentration techniques was much more beneficial for the concentration of positively charged vitamins. Comparing with the conventional injection mode, the enhancement in the detection sensitivities of water-soluble vitamins using the on-line concentration technique is in the range of 3 to 35-fold. The developed pCEC method was applied to evaluate water-soluble vitamins in corns.

  17. Liquid chromatography with isotope-dilution mass spectrometry for determination of water-soluble vitamins in foods.

    Science.gov (United States)

    Phillips, Melissa M

    2015-04-01

    Vitamins are essential for improving and maintaining human health, and the main source of vitamins is the diet. Measurement of the quantities of water-soluble vitamins in common food materials is important to understand the impact of vitamin intake on human health, and also to provide necessary information for regulators to determine adequate intakes. Liquid chromatography (LC) and mass spectrometry (MS) based methods for water-soluble vitamin analysis are abundant in the literature, but most focus on only fortified foods or dietary supplements or allow determination of only a single vitamin. In this work, a method based on LC/MS and LC/MS/MS has been developed to allow simultaneous quantitation of eight water-soluble vitamins, including multiple forms of vitamins B3 and B6, in a variety of fortified and unfortified food-matrix Standard Reference Materials (SRMs). Optimization of extraction of unbound vitamin forms and confirmation using data from external laboratories ensured accuracy in the assigned values, and addition of stable isotope labeled internal standards for each of the vitamins allowed for increased precision.

  18. Simultaneous determination of water-soluble vitamins in beverages and dietary supplements by LC-MS/MS.

    Science.gov (United States)

    Kakitani, Ayano; Inoue, Tomonori; Matsumoto, Keiko; Watanabe, Jun; Nagatomi, Yasushi; Mochizuki, Naoki

    2014-01-01

    An LC-MS/MS method was developed for the simultaneous determination of 15 water-soluble vitamins that are widely used as additives in beverages and dietary supplements. This combined method involves the following simple pre-treatment procedures: dietary supplement samples were prepared by centrifugation and filtration after an extraction step, whereas beverage samples were diluted prior to injection. Chromatographic analysis in this method utilised a multi-mode ODS column, which provided reverse-phase, anion- and cation-exchange capacities, and therefore improved the retention of highly polar analytes such as water-soluble vitamins. Additionally, the multi-mode ODS column did not require adding ion pair reagents to the mobile phase. We optimised the chromatographic separation of 15 water-soluble vitamins by adjusting the mobile phase pH and the organic solvent. We also conducted an analysis of a NIST Standard Reference Material (SRM 3280 Multi-vitamin/Multi-element tablets) using this method to verify its accuracy. In addition, the method was applied to identify the vitamins in commercial beverages and dietary supplements. By comparing results with the label values and results obtained by official methods, it was concluded that the method could be used for quality control and to compose nutrition labels for vitamin-enriched products.

  19. Spectroscopic study of the water-soluble organic matter isolated from atmospheric aerosols collected under different atmospheric conditions

    International Nuclear Information System (INIS)

    Duarte, Regina M.B.O.; Pio, Casimiro A.; Duarte, Armando C.

    2005-01-01

    The composition of the water-soluble organic matter from fine aerosols collected in a rural location during two different meteorological conditions (summer and autumn) was investigated by UV-vis, synchronous fluorescence (with Δλ = 20 nm), FT-IR and CPMAS- 13 C NMR spectroscopies. A seasonal variation in the concentration of total carbon, organic carbon and water-soluble organic carbon was confirmed, with higher values during the autumn and lower values during the summer season. The chemical characterisation of the water-soluble organic matter showed that both samples are dominated by a high content of aliphatic structures, carboxyl groups and aliphatic carbons single bonded to one oxygen or nitrogen atom. However, the autumn sample exhibits a higher aromatic content than the summer sample, plus signals due to carbons of phenol, ketones and methoxyl groups. These signals were attributed to lignin breakdown products which are likely to be released during wood combustion processes. The obtained results put into evidence the major contribution of biomass burning processes in domestic fireplaces during low temperature conditions into both the concentration and the bulk chemical properties of the WSOC from fine aerosols

  20. An Intestinal "Transformers"-like Nanocarrier System for Enhancing the Oral Bioavailability of Poorly Water-Soluble Drugs.

    Science.gov (United States)

    Chuang, Er-Yuan; Lin, Kun-Ju; Huang, Tring-Yo; Chen, Hsin-Lung; Miao, Yang-Bao; Lin, Po-Yen; Chen, Chiung-Tong; Juang, Jyuhn-Huarng; Sung, Hsing-Wen

    2018-06-06

    Increasing the intestinal dissolution of orally administered poorly water-soluble drugs that have poor oral bioavailability to a therapeutically effective level has long been an elusive goal. In this work, an approach that can greatly enhance the oral bioavailability of a poorly water-soluble drug such as curcumin (CUR) is developed, using a "Transformers"-like nanocarrier system (TLNS) that can self-emulsify the drug molecules in the intestinal lumen to form nanoemulsions. Owing to its known anti-inflammation activity, the use of CUR in treating pancreatitis is evaluated herein. Structural changes of the TLNS in the intestinal environment to form the CUR-laden nanoemulsions are confirmed in vitro. The therapeutic efficacy of this TLNS is evaluated in rats with experimentally induced acute pancreatitis (AP). Notably, the CUR-laden nanoemulsions that are obtained using the proposed TLNS can passively target intestinal M cells, in which they are transcytosed and then transported into the pancreatic tissues via the intestinal lymphatic system. The pancreases in rats that are treated with the TLNS yield approximately 12 times stronger CUR signals than their counterparts receiving free CUR, potentially improving the recovery of AP. These findings demonstrate that the proposed TLNS can markedly increase the intestinal drug dissolution, making oral delivery a favorable noninvasive means of administering poorly water-soluble drugs.

  1. A water-soluble, mucoadhesive quaternary ammonium chitosan-methyl-β-cyclodextrin conjugate forming inclusion complexes with dexamethasone.

    Science.gov (United States)

    Piras, Anna Maria; Zambito, Ylenia; Burgalassi, Susi; Monti, Daniela; Tampucci, Silvia; Terreni, Eleonora; Fabiano, Angela; Balzano, Federica; Uccello-Barretta, Gloria; Chetoni, Patrizia

    2018-03-30

    The ocular bioavailability of lipophilic drugs, such as dexamethasone, depends on both drug water solubility and mucoadhesion/permeation. Cyclodextrins and chitosan are frequently employed to either improve drug solubility or prolong drug contact onto mucosae, respectively. Although the covalent conjugation of cyclodextrin and chitosan brings to mucoadhesive drug complexes, their water solubility is restricted to acidic pHs. This paper describes a straightforward grafting of methyl-β-cyclodextrin (MCD) on quaternary ammonium chitosan (QA-Ch60), mediated by hexamethylene diisocyanate. The resulting product is a water-soluble chitosan derivative, having a 10-atom long spacer between the quaternized chitosan and the cyclodextrin. The derivative is capable of complexing the model drug dexamethasone and stable complexes were also observed for the lyophilized products. Furthermore, the conjugate preserves the mucoadhesive properties typical of quaternized chitosan and its safety as solubilizing excipient for ophthalmic applications was preliminary assessed by in vitro cytotoxicity evaluations. Taken as a whole, the observed features appear promising for future processing of the developed product into 3D solid forms, such as controlled drug delivery systems, films or drug eluting medical devices.

  2. Survey on synthesis and reaction of environmentally benign water-soluble metal complex catalysts; Kankyo chowagata suiyosei sakutai shokubai no gosei hanno no chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This report describes the research trend survey results on the synthesis and reaction of water-soluble metal complexes which are regarded as environmentally benign catalysts. For the synthesis and catalysis of water-soluble complexes, synthetic methods of water-soluble phosphines, such as sulfonated TPPMS and TPPTS, are described in detail. Synthesis and reactivity of hydroxymethylphosphines are introduced, and the application of electrospray mass spectroscopy is elucidated as a tool for the analysis of them. Changes of the application of transition metal complexes with water-soluble phosphines to catalysis are described. Dual catalysts which have both functions of phase transfer catalysts and homogeneous catalysts are introduced. Concept of counter phase transfer catalysts is also introduced, and some catalytic reactions are described. In addition, this report introduces catalysis of water-soluble polymer-supported metal complexes, immobilization of metal colloids with water-soluble ligands and their analysis, and water-soluble complexes as hybrid catalysts. 144 refs., 94 figs., 10 tabs.

  3. Electrochromic Behaviors of Water-Soluble Polyaniline with Covalently Bonded Acetyl Ferrocene

    Science.gov (United States)

    Xiong, Shanxin; Wang, Ru; Li, Shuaishuai; Wu, Bohua; Chu, Jia; Wang, Xiaoqin; Zhang, Runlan; Gong, Ming

    2018-04-01

    A novel ferrocene-containing hybrid electrochromic material was synthesized via copolymerization of aniline with p-phenylenediamine functionalized acetyl ferrocene in the presence of poly (styrene sulfonate) dopant in an aqueous medium, and neat polyaniline (PANI) was prepared for comparison. The polymerization characteristics and the structure of the copolymer were systematically studied by Fourier-transform infrared, meanwhile, their electrochromic properties and electrochemical behaviors were tested by UV-vis spectra, cyclic voltammetry and electrochemical impedance spectroscopy (EIS). It was found that the strong covalent bond and large conjugated system between PANI and ferrocene enhance the electron transfer rate and electron delocalization in the ferrocene-polyaniline (Fc-PANI) hybrid. In particular, the electrochromic device with Fc-PANI as the active layer shows significant enhancement in optical contrast over the PANI-based device.

  4. Tailoring magnetic properties of self-biased hexaferrites using an alternative copolymer of isobutylene and maleic anhydride

    Science.gov (United States)

    Wu, Chuanjian; Yu, Zhong; Sokolov, Alexander S.; Yu, Chengju; Sun, Ke; Jiang, Xiaona; Lan, Zhongwen; Harris, Vincent G.

    2018-05-01

    Discussed is a novel self-biased hexaferrite gelling system based on a nontoxic and water-soluble copolymer of isobutylene and maleic anhydride. This copolymer simultaneously acts as a dispersant and gelling agent, and recently received much attention from the ceramics community. Herein its effects on the rheological conditions throughout magnetic-field pressing, and consequently, orientation, density and magnetic properties of textured hexaferrites were investigated. Ka-band FMR linewidths were measured, and the crystalline anisotropy and porosity induced linewidth broadening were estimated according to Schlömann's theory. The copolymer allowed to reduce the friction between micron-sized magnetic particulates, resulting in higher density and degree of crystalline orientation, and lower FMR linewidth.

  5. Novel water-soluble polyurethane nanomicelles for cancer chemotherapy: physicochemical characterization and cellular activities

    Directory of Open Access Journals (Sweden)

    Khosroushahi Ahmad

    2012-01-01

    Full Text Available Abstract Background Efficient delivery of anticancer chemotherapies such as paclitaxel (PTX can improve treatment strategy in a variety of tumors such as breast and ovarian cancers. Accordingly, researches on polymeric nanomicelles continue to find suitable delivery systems. However, due to biocompatibility concerns, a few micellar nanoformulations have exquisitely been translated into clinical uses. Here, we report the synthesis of novel water-soluble nanomicelles using bioactive polyurethane (PU polymer and efficient delivery of PTX in the human breast cancer MCF-7 cells. Results The amphiphilic polyurethane was prepared through formation of urethane bounds between hydroxyl groups in poly (tetramethylene ether glycol (PTMEG and dimethylol propionic acid with isocyanate groups in toluene diisocyanate (TDI. The free isocyanate groups were blocked with phenol, while the free carboxyl groups of dimethylol propionic acid were reacted with triethylamine to attain ionic centers in the polymer backbone. These hydrophobic PTMEG blocks displayed self-assembly forming polymeric nanomicelles in water. The PTX loaded PU nanomicelles showed suitable physical stability, negative zeta potential charge (-43 and high loading efficiency (80% with low level of critical micelle concentration (CMC. In vitro drug release profile showed a faster rate of drug liberation at pH 5.4 as compared to that of pH 7.4, implying involvement of a pH-sensitive mechanism for drug release from the nanomicelles. The kinetic of release exquisitely obeyed the Higuchi model, confirming involvement of diffusion and somewhat erosion at pH 5.4. These nanomicelles significantly inhibited the growth and proliferation of the human breast cancer MCF-7 cells, leading them to apoptosis. The real time RT-PCR analysis confirmed the activation of apoptosis as result of liberation of cytochrome c in the cells treated with the PTX loaded PU nanomicelles. The comet assay analysis showed somewhat DNA

  6. Water soluble ions in aerosols (TSP) : Characteristics, sources and seasonal variation over the central Himalayas, Nepal

    Science.gov (United States)

    Tripathee, Lekhendra; Kang, Shichang; Zhang, Qianggong; Rupakheti, Dipesh

    2016-04-01

    Atmspheric pollutants transported from South Asia could have adverse impact on the Himalayan ecosystems. Investigation of aerosol chemistry in the Himalayan region in Nepal has been limited on a temporal and spatial scale to date. Therefore, the water-soluble ionic composition of aerosol using TSP sampler was investigated for a year period from April 2013 to March 2014 at four sites Bode, Dhunche, Lumbini and Jomsom characterized as an urban, rural, semi-urban and remote sites in Nepal. During the study period, the highest concentration of major cation was Ca2+ with an average concentration of 8.91, 2.17, 7.85 and 6.42 μg m-3 and the highest concentration of major anion was SO42- with an average of 10.96, 4.06, 6.85 and 3.30 μg m-3 at Bode, Dhunche, Lumbini and Jomsom respectively. The soluble ions showed the decrease in concentrations from urban to the rural site. Correlations and PCA analysis suggested that that SO42-, NO3- and NH4+ were derived from the anthropogenic sources where as the Ca2+ and Mg2+ were from crustal sources. Our results also suggest that the largest acid neutralizing agent at our sampling sites in the central Himalayas are Ca2+ followed by NH4+. Seasonal variations of soluble ions in aerosols showed higher concentrations during pre-monsoon and winter (dry-periods) due to limited precipitation amount and lower concentrations during the monsoon which can be explained by the dilution effect, higher the precipitation lower the concentration. K+ which is regarded as the tracer of biomss burning had a significant peaks during pre-monsoon season when the forest fires are active around the regions. In general, the results of this study suggests that the atmospheric chemistry is influenced by natural and anthropogenic sources. Thus, soluble ionic concentrations in aerosols from central Himalayas, Nepal can provide a useful database to assess atmospheric environment and its impacts on human health and ecosystem in the southern side of central

  7. Enhancement of quercetin water solubility with steviol glucosides and the studies of biological properties

    Directory of Open Access Journals (Sweden)

    Thi Thanh Hanh Nguyen

    2015-12-01

    rebaudioside or rubusoside treatment. As Ru concentration increases, the solubility of quercetin in water increases. The solubilization of quercetin in Ru solution did not reduce its biological functions such as the DPPH radical-scavenging and mushroom tyrosinase activity; also, quercetin-rubusoside increased the inhibition activity against the 3CLpro of SARS and human intestinal maltase, when compared with the activity of quercetin in DMSO. Thus, rubusoside and rebaudioside are promising compounds which enhance the solubility of poorly water soluble compounds.

  8. Development and in vitro evaluation of sustained release multiparticulate tablet of freely water soluble drug

    Directory of Open Access Journals (Sweden)

    Ashlesha Pravin Pandit

    2010-09-01

    Full Text Available Blends of aqueous dispersion of a hydrophobic and hydrophilic polymer, namely Surelease®: hydroxypropyl methylcellulose (Surelease®: HPMC E15 were used as coating materials to control the drug release from coated pellets of the highly water soluble drug metoprolol succinate. Varying the polymer blends, ranges of drug release patterns were obtained at pH 6.8. The present study dealt with diffusion of drug through plasticized Surelease®/ hydroxypropyl methylcellulose (HPMC E15 films prepared by coating of drug and polymers onto non-pareil seeds using the solution layering technique. The release of metoprolol succinate from coated pellets was decreased with increased coating load of polymer. The optimized formulation was obtained by 3² full factorial design. The release profile revealed that the optimized formulation follows zero order release kinetics. The stability data showed no interaction for storage at 25ºC and 60% relative humidity.Misturas das dispersões aquosas de polímero hidrofóbico e de polímero hidrofílico, a saber, Surelease®: hidroxipropil metilcelulose (Surelease®: HPMC E15, foram utilizadas como material de revestimento para controlar a liberação de fármacos de péletes revestidos de fármaco altamente solúvel, o succinato de metoprolol. Variando as misturas de polímeros, obtiveram-se faixas de padrão de liberação do fármaco em pH 6,8. O presente estudo tratou da difusão do fármaco através de filmes de Surelease®/hidroxipropil metilcelulose(HPMC E15, preparados pelo revestimento do fármaco e dos polímeros em sementes nonpareil, utilizando técnica de solução em camada. A liberação de succinato de metoprolol dos péletes revestidos diminuiu com o aumento da carga de polímero de revestimento. A formulação otimizada foi obtida por planejamento fatorial 3². O perfil de liberação revelou que a formulação otimizada segue a cinética de liberação de ordem zero. Os dados de estabilidade mostraram n

  9. [Sufficiency with water-soluble vitamins and state of bone in pregnant women].

    Science.gov (United States)

    Vrzhesinskaya, O A; Pereverzeva, O G; Gmoshinskaya, M V; Kodentsova, V M; Safronova, A I; Korosteleva, M M; Aleshina, I V; Fandeeva, T A

    2015-01-01

    Vitamin status and bone strength have been estimated in 91 pregnant women (29.3 ± 4.6 years old) from Moscow by non-invasive methods. Sufficiency with vitamins C, B2, B6 has been evaluated by morning urinary excretion of ascorbic acid, riboflavin and 4-piridoxic acid determined by visual titration and fluorimetric methods. The rate of bone resorption has been measured by the ratio of urinary calcium and creatinine, determined by complexometric titration and spectrophotometrically. The study of the bone strength has been conducted using an ultrasonic densitometer (the speed of the ultrasonic waves along the cortical layer). The lack of vitamin C was found in 20.4% .of the women surveyed, vitamin B2--in 27.4%. Vitamin B6 deficiency was detected most frequently (90%). Excretion of vitamins B2 and B6 in women in the third trimester of pregnancy was lower as compared with the women in the first and second trimester. In 53.3% of the women surveyed an increase in urinary excretion of calcium per creatinine has been observed. Excretion of group B vitamins (especially vitamin B6, 1.75 fold, p vitamin supplements was higher compared to non-taking vitamins that indicates the better sufficiency of the organism with these vitamins. Among women who took vitamin complexes, inadequate supply with water-soluble vitamins C, B2 and B6 was detected less frequently (the difference was significant for vitamin B2) than among women who did not intake vitamin complexes (in 11.9, 27.7 and 42.4% vs 16.1, 54.8 and 48.8 %). The rate of bone resorption (Ca/creatinine) in women taking vitamins was smaller (0.19 ± 0.09 vs 0.24 ± 0.14, p > 0.05). Ca/creatinine ratio was within normal range in 40% of women who intake vitamins, while in women not taking vitamins--only in 22.2%; this value exceeded the upper limit of norm in the rest. The strength of bone was broken in women in the second and third trimester of pregnancy, having worse supply of vitamins. The percentage of agreement of the results

  10. Solution properties of targacanthin (water-soluble part of gum tragacanth exudate from Astragalus gossypinus).

    Science.gov (United States)

    Mohammadifar, Mohammad Amin; Musavi, Seyed Mohammad; Kiumarsi, Amir; Williams, Peter A

    2006-02-28

    Solution properties of tragacanthin (the water-soluble part of gum tragacanth) were studied by gel permeation chromatography (GPC) combined with multi-angle light scattering and viscometry at 25 degrees C. Photon correlation spectroscopy was used to determine the hydrodynamic radius. Ultrasonic degradation was applied to obtain biopolymer fractions of different molecular weights. The dependence of intrinsic viscosity [eta] and radius of gyration (s2)z(1/2) on weight average molecular mass M(w) for this biopolymer were found to be [eta] = 9.077 x 10(-5) M(w)(0.87) (dL g(-1)) and (s2)z(1/2) in the range of M(w) from 1.8 x 10(5) to 1.6 x 10(6). The conformational parameters of tragacanthin were calculated to be 1111 nm for molar mass per unit contour length (M(L)), 26 nm for persistence length (q) and 1.87 ratio of R(g)/R(h). It was found that the Smidsrød parameter B, the empirical stiffness parameter was 0.013, which is lower than that of several polysaccharides indicating the stiff backbone for tragacanthin. The rheological behavior of aqueous solutions of gum tragacanth and its insoluble and soluble fractions (bassorin and tragacanthin, respectively) were studied. For concentrations equal to 1%, at 25 degrees C and in the absence of salt, bassorin solution showed the highest viscosity and shear thinning behaviour. Power law and Williamson models were used to describe the rheological behaviour of bassorin and tragacanthin, respectively. Oscillatory shear experiments showed a gel like structure for the bassorin but for tragacanthin the oscillatory data were as would be expected for semi-dilute to concentrated solution of entangled, random coil polymers. NaCl changed the steady and oscillatory rheological properties of both fractions and in this way the final viscosity of bassorin was even less than tragacanthin. The calculated activation energy for bassorin and tragacanthin indicated a more rapid decrease in viscosity with temperature for tragacanthin. The plot of

  11. Structural and Mechanical Hysteresis at the Order-Order Transition of Block Copolymer Micellar Crystals

    Directory of Open Access Journals (Sweden)

    Theresa A. LaFollette

    2011-01-01

    Full Text Available Concentrated solutions of a water-soluble block copolymer (PEO20-(PPO70-(PEO20 show a thermoreversible transition from a liquid to a gel. Over a range of concentration there also exists an order-order transition (OOT between cubically-packed spherical micelles and hexagonally-packed cylindrical micelles. This OOT displays a hysteresis between the heating and cooling transitions that is observed at both the macroscale through rheology and nanoscale through small angle neutron scattering (SANS. The hysteresis is caused by the persistence of the cubically-packed spherical micelle phase into the hexagonally-packed cylindrical micelle phase likely due to the hindered realignment of the spherical micelles into cylindrical micelles and then packing of the cylindrical micelles into a hexagonally-packed cylindrical micelle phase. This type of hysteresis must be fully characterized, and possibly avoided, for these block copolymer systems to be used as templates in nanocomposites.

  12. Hyaluronic Acid Graft Copolymers with Cleavable Arms as Potential Intravitreal Drug Delivery Vehicles.

    Science.gov (United States)

    Borke, Tina; Najberg, Mathie; Ilina, Polina; Bhattacharya, Madhushree; Urtti, Arto; Tenhu, Heikki; Hietala, Sami

    2018-01-01

    Treatment of retinal diseases currently demands frequent intravitreal injections due to rapid clearance of the therapeutics. The use of high molecular weight polymers can extend the residence time in the vitreous and prolong the injection intervals. This study reports a water soluble graft copolymer as a potential vehicle for sustained intravitreal drug delivery. The copolymer features a high molecular weight hyaluronic acid (HA) backbone and poly(glyceryl glycerol) (PGG) side chains attached via hydrolysable ester linkers. PGG, a polyether with 1,2-diol groups in every repeating unit available for conjugation, serves as a detachable carrier. The influence of synthesis conditions and incubation in physiological media on the molecular weight of HA is studied. The cleavage of the PGG grafts from the HA backbone is quantified and polymer-from-polymer release kinetics are determined. The biocompatibility of the materials is tested in different cell cultures. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Synthesis of water-soluble, multiple functionalizable dendrons for the conversion of large dendrimers or other molecular objects into potential drug carriers.

    Science.gov (United States)

    Müller, Stephan; Schlüter, A Dieter

    2005-09-19

    The synthesis of dendrons and dendrimers which carry OEG chains and bidentate ligands and/or fluorescence tags is described. The orthogonally protected functional groups of the dendrons allow modification of the substitution pattern and attachment to larger entities. Both dendrons and dendrimers are highly water-soluble. The dendrons should have considerable potential to convert, for example, commercially available, high-generation dendrimers into water-soluble, versatile support materials for antitumor therapy.

  14. Studies for the use of water soluble chelating polymer in ultra-filtration technique for the removal of uranium from aqueous solutions

    International Nuclear Information System (INIS)

    Misra, S.K.; Mahatele, A.K.; Tripathi, S.C.; Vijayan, K.; Munshi, S.K.

    2005-01-01

    Studies were carried out for the removal of uranium from aqueous medium using water soluble chelating polymer by ultra-filtration technique. The water soluble polymers are the option for the surfactants used in the micellar enhanced ultra-filtration technique. More than 95% separation of uranium carried out under different experimental conditions, suggest that the technique can be effectively employed for the removal uranium from the aqueous effluent streams. (author)

  15. Evaluation of a water-soluble bioadhesive patch for photodynamic therapy of vulval lesions.

    Science.gov (United States)

    McCarron, Paul A; Donnelly, Ryan F; Zawislak, Agnieszka; Woolfson, A David; Price, John H; McClelland, Raymond

    2005-04-11

    An innovative bioadhesive patch intended primarily as a vulval drug delivery system and, specifically, as a means to deliver photosensitisers, or their prodrugs, for photodynamic purposes is described. The patch was formulated with a copolymer of methyl vinyl ether and maleic anhydride (PMVE/MA) as a bioadhesive matrix and poly(vinyl chloride) as a drug-impervious backing layer. Adhesive strength to neonate porcine skin, as a model substrate, was evaluated using peel and tensile testing measurements. Acceptabilities of non-drug loaded patches were appraised using human volunteers and visual-analogue scoring devices. An optimal formulation, with water uptake and peel strengths appropriate for vulval drug delivery, was cast from a 20% (w/w) PMVE/MA solution and adhered with a strength of approximately 1.7 Ncm(-2). Patient evaluation demonstrated comfort and firm attachment for up to 4h in mobile patients. Aminolevulinic acid, a commonly used photosensitiser, was formulated into the candidate formulation and applied to vulval intraepithelial neoplastic lesions. Fluorescence under ultraviolet illumination revealed protoporphyrin synthesis. The patch achieves the extended application times obligatory in topical photodynamic therapy of vulval lesions, thereby contributing to potential methods for the eradication of neoplastic lesions in the lower female reproductive tract.

  16. Synthesis and Evaluation of a Water-Soluble Hyperbranched Polymer as Enhanced Oil Recovery Chemical

    Directory of Open Access Journals (Sweden)

    Nanjun Lai

    2013-01-01

    Full Text Available A novel hyperbranched polymer was synthesized using acrylamide (AM, acrylic acid (AA, N-vinyl-2-pyrrolidone (NVP, and dendrite functional monomer as raw materials by redox initiation system in an aqueous medium. The hyperbranched polymer was characterized by infrared (IR spectroscopy, 1H NMR spectroscopy, 13C NMR spectroscopy, elemental analysis, and scanning electron microscope (SEM. The viscosity retention rate of the hyperbranched polymer was 22.89% higher than that of the AM/AA copolymer (HPAM at 95°C, and the viscosity retention rate was 8.17%, 12.49%, and 13.68% higher than that of HPAM in 18000 mg/L NaCl, 1800 mg/L CaCl2, and 1800 mg/L MgCl2·6H2O brine, respectively. The hyperbranched polymer exhibited higher apparent viscosity (25.2 mPa·s versus 8.1 mPa·s under 500 s−1 shear rate at 80°C. Furthermore, the enhanced oil recovery (EOR of 1500 mg/L hyperbranched polymer solutions was up to 23.51% by the core flooding test at 80°C.

  17. Exploitation of 3D face-centered cubic mesoporous silica as a carrier for a poorly water soluble drug: Influence of pore size on release rate

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Wenquan; Wan, Long; Zhang, Chen; Gao, Yikun; Zheng, Xin; Jiang, Tongying; Wang, Siling, E-mail: silingwang@syphu.edu.cn

    2014-01-01

    The purposes of the present work were to explore the potential application of 3D face-centered cubic mesoporous silica (FMS) with pore size of 16.0 nm as a delivery system for poorly soluble drugs and investigate the effect of pore size on the dissolution rate. FMS with different pore sizes (16.0, 6.9 and 3.7 nm) was successfully synthesized by using Pluronic block co-polymer F127 as a template and adjusting the reaction temperatures. Celecoxib (CEL), which is a BCS class II drug, was used as a model drug and loaded into FMS with different pore sizes by the solvent deposition method at a drug–silica ratio of 1:4. Characterization using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformation infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), nitrogen adsorption, X-ray diffraction (XRD), and differential scanning calorimetry (DSC) was used to systematically investigate the drug loading process. The results obtained showed that CEL was in a non-crystalline state after incorporation of CEL into the pores of FMS-15 with pore size of 16.0 nm. In vitro dissolution was carried out to demonstrate the effects of FMS with different pore sizes on the release of CEL. The results obtained indicated that the dissolution rate of CEL from FMS-15 was significantly enhanced compared with pure CEL. This could be explained by supposing that CEL encountered less diffusion resistance and its crystallinity decreased due to the large pore size of 16.0 nm and the nanopore channels of FMS-15. Moreover, drug loading and pore size both play an important role in enhancing the dissolution properties for the poorly water-soluble drugs. As the pore size between 3.7 and 16.0 nm increased, the dissolution rate of CEL from FMS gradually increased. - Highlights: • Exploitation of 3D cubic mesoporous silica (16 nm) as a carrier was completed. • The release rate of CEL increased on increasing the pore size of carriers. • The crystallinity

  18. Characterization of the size-segregated water-soluble inorganic ions at eight Canadian rural sites

    Directory of Open Access Journals (Sweden)

    L. Zhang

    2008-12-01

    Full Text Available Size-segregated water-soluble inorganic ions, including particulate sulphate (SO42-, nitrate (NO3-, ammonium (NH4+, chloride (Cl-, and base cations (K+, Na+, Mg2+, Ca2+, were measured using a Micro-Orifice Uniform Deposit Impactor (MOUDI during fourteen short-term field campaigns at eight locations in both polluted and remote regions of eastern and central Canada. The size distributions of SO42- and NH4+ were unimodal, peaking at 0.3–0.6 µm in diameter, during most of the campaigns, although a bimodal distribution was found during one campaign and a trimodal distribution was found during another campaign made at a coastal site. SO42- peaked at slightly larger sizes in the cold seasons (0.5–0.6 µm compared to the hot seasons (0.3–0.4 µm due to the higher relative humidity in the cold seasons. The size distributions of NO3- were unimodal, peaking at 4.0–7.0 µm during the warm-season campaigns, and bimodal, with one peak at 0.3–0.6 µm and another at 4–7 µm during the cold-season campaigns. A unimodal size distribution, peaking at 4–6 µm, was found for Cl-, Na+, Mg2+, and Ca2+ during approximately half of the campaigns and a bimodal distribution, with one peak at 2 µm and the other at 6 µm, was found during the rest of the campaigns. For K+, a bimodal distribution, with one peak at 0.3 µm and the other at 4 µm, was observed during most of the campaigns. Seasonal contrasts in the size-distribution profiles suggest that emission sources and air mass origins were the major factors controlling the size distributions of the primary aerosols while meteorological conditions were more important for the secondary aerosols.

    The dependence of the particle acidity on

  19. Comparison of lead removal behaviors and generation of water-soluble sodium compounds in molten lead glass under a reductive atmosphere

    Science.gov (United States)

    Okada, Takashi; Nishimura, Fumihiro; Xu, Zhanglian; Yonezawa, Susumu

    2018-06-01

    We propose a method of reduction-melting at 1000 °C, using a sodium-based flux, to recover lead from cathode-ray tube funnel glass. To recover the added sodium from the treated glass, we combined a reduction-melting process with a subsequent annealing step at 700 °C, generating water-soluble sodium compounds in the molten glass. Using this combined process, this study compares lead removal behavior and the generation of water-soluble sodium compounds (sodium silicates and carbonates) in order to gain fundamental information to enhance the recovery of both lead and sodium. We find that lead removal increases with increasing melting time, whereas the generation efficiency of water-soluble sodium increases and decreases periodically. In particular, near 90% lead removal, the generation of water-soluble sodium compounds decreased sharply, increasing again with the prolongation of melting time. This is due to the different crystallization and phase separation efficiencies of water-soluble sodium in molten glass, whose structure continuously changes with lead removal. Previous studies used a melting time of 60 min in the processes. However, in this study, we observe that a melting time of 180 min enhances the water-soluble sodium generation efficiency.

  20. Water-Soluble Pd8L4 Self-assembled Molecular Barrel as an Aqueous Carrier for Hydrophobic Curcumin.

    Science.gov (United States)

    Bhat, Imtiyaz Ahmad; Jain, Ruchi; Siddiqui, Mujahuddin M; Saini, Deepak K; Mukherjee, Partha Sarathi

    2017-05-01

    A tetrafacial water-soluble molecular barrel (1) was synthesized by coordination driven self-assembly of a symmetrical tetrapyridyl donor (L) with a cis-blocked 90° acceptor [cis-(en)Pd(NO 3 ) 2 ] (en = ethane-1,2-diamine). The open barrel structure of (1) was confirmed by single crystal X-ray diffraction. The presence of a hydrophobic cavity with large windows makes it an ideal candidate for encapsulation and carrying hydrophobic drug like curcumin in an aqueous medium. The barrel (1) encapsulates curcumin inside its molecular cavity and protects highly photosensitive curcumin from photodegradation. The photostability of encapsulated curcumin is due to the absorption of a high proportion of the incident photons by the aromatic walls of 1 with a high absorption cross-sectional area, which helps the walls to shield the guest even against sunlight/UV radiations. As compared to free curcumin in water, we noticed a significant increase in solubility as well as cellular uptake of curcumin upon encapsulation inside the water-soluble molecular barrel (1) in aqueous medium. Fluorescence imaging confirmed that curcumin was delivered into HeLa cancer cells by the aqueous barrel (1) with the retention of its potential anticancer activity. While free curcumin is inactive toward cancer cells in aqueous medium at room temperature due to negligible solubility, the determined IC 50 value of ∼14 μM for curcumin in aqueous medium in the presence of the barrel (1) reflects the efficiency of the barrel as a potential curcumin carrier in aqueous medium without any other additives. Thus, two major challenges of increasing the bioavailability and stability of curcumin in aqueous medium even in the presence of UV light have been addressed by using a new supramolecular water-soluble barrel (1) as a drug carrier.