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Sample records for water soluble contrast

  1. Diagnostic image quality of hysterosalpingography: ionic versus non ionic water soluble iodinated contrast media

    Science.gov (United States)

    Mohd Nor, H; Jayapragasam, KJ; Abdullah, BJJ

    2009-01-01

    Objective To compare the diagnostic image quality between three different water soluble iodinated contrast media in hysterosalpingography (HSG). Material and method In a prospective randomised study of 204 patients, the diagnostic quality of images obtained after hysterosalpingography were evaluated using Iopramide (106 patients) and Ioxaglate (98 patients). 114 patients who had undergone HSG examination using Iodamide were analysed retrospectively. Image quality was assessed by three radiologists independently based on an objective set of criteria. The obtained results were statistically analysed using Kruskal-Wallis and Mann-Whitney U test. Results Visualisation of fimbrial rugae was significantly better with Iopramide and Ioxaglate than Iodamide. All contrast media provided acceptable diagnostic image quality with regard to uterine, fallopian tubes outline and peritoneal spill. Uterine opacification was noted to be too dense in all three contrast media and not optimal for the assessment of intrauterine pathology. Higher incidence of contrast intravasation was noted in the Iodamide group. Similarly, the numbers of patients diagnosed with bilateral blocked fallopian tubes were also higher in the Iodamide group. Conclusion HSG using low osmolar contrast media (Iopramide and Ioxaglate) demonstrated diagnostic image qualities similar to HSG using conventional high osmolar contrast media (Iodamide). However, all three contrast media were found to be too dense for the detection of intrauterine pathology. Better visualisation of the fimbrial outline using Ioxaglate and Iopramide were attributed to their low contrast viscosity. The increased incidence of contrast media intravasation and bilateral tubal blockage using Iodamide are probably related to the high viscosity. PMID:21611058

  2. Lumbar myelography using water-soluble contrast media. Lumbale Myelographie mit wasserloelichen Kontrastmitteln. Lehrbuch und Atlas

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    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.

  3. The haemodynamic effects of iodinated water soluble radiographic contrast media: a review

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    Morcos, S.K. [Department of Diagnostic Imaging, Northern General Hospital NHS Trust, Sheffield S5 7AU (United Kingdom); Dawson, P. [Department of Imaging, Hammersmith Hospital, London W12 0NN (United Kingdom); Pearson, J.D. [Vascular Biology Research Centre, King' s College, Kensington, London W8 7AH (United Kingdom); Jeremy, J.Y. [Bristol Heart Institute, Bristol BS2 8HW (United Kingdom); Davenport, A.P. [Clinical Pharmacology Unit, University of Cambridge, Addenbrookes Hospital, Cambridge CB2 2QQ (United Kingdom); Yates, M.S. [Department of Pharmacology, University of Leeds, Leeds LS2 9JT (United Kingdom); Tirone, P.; Cipolla, P.; Haeen, C. de [Contrast Media Research, Bracco, Milan (Italy); Muschick, P.; Krause, W. [Contrast Media Research, Schering AG, Berlin (Germany); Refsum, H. [Research and Development, Nycomed Imaging AS and University of Oslo, Institute for Experimental Medical Research, Ullevaal Hospital, Oslo (Norway); Emery, C.J. [Department of Respiratory Medicine, Division of Clinical Sciences, University of Sheffield, Sheffield (United Kingdom); Liss, P.; Nygren, A. [Department of Diagnostic Radiology, University Hospital, S-751 85 Uppsala (Sweden); Haylor, J. [Sheffield Kidney Institute, Northern General Hospital, Sheffield (United Kingdom); Pugh, N.D. [Department of Medical Physics and Bioengineering, University Hospital of Wales, Heath Park, Cardiff CF4 4XW (United Kingdom); Karlsson, J.O.G. [Department of Physiology and Biomedical Engineering, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim (Norway)

    1998-11-01

    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. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Effect of water-soluble contrast in colorectal surgery: A prospective randomized trial

    Institute of Scientific and Technical Information of China (English)

    Jia-Hui Chen; Chung-Bao Hsieh; Pei-Chieh Chao; Hsiao-Dung Liu; Chung-Jueng Chen; Yao-Chi Liu; Jyh-Cherng Yu

    2005-01-01

    AIM: Postoperative gastrointestinal-tract motility is normally delayed. Early feeding after colorectal surgery has beenreposed recently, but late feeding is common. Gastrografin not only enhances bowel peristalsis, but also decreases bowel-wall edema. Whether contrast medium allows early oral feeding and reduces the duration of hospitalization requires clarification.METHODS: Fifty patients underwent elective colorectal surgery in a regional medical center. Patients were prospectively randomized into a Gastrografin group or control group (n = 25 each). Patients in the Gastrografin group began their feeding schedule with 100 mL of 5% dextrose water with 100 mL of Gastrografin on postoperative d 3 and were advanced to a full liquid diet when the contrast reached the colon in 4 h. Patients in the control group began their feeding schedule with 200 mL of 5% dextrosewater on postoperative d 3 and were advanced to a full liquid diet after the passage of flatus and stool. Nasogastric tubes were inserted for persistent postoperative vomiting. Fullness, nausea, vomiting, complications, time of anesthesia, time of operation, time of mobilization, time of oral feeding, and duration of hospital stay were recorded and analyzed with Student's t-test.RESULTS: In the Gastrografin group, one patient hadaspiration pneumonia and one patient had anastomotic leakage resulting in sepsis and eventual death. This mortality was excluded from the subsequent statistical analysis. In the control group, two patients had wound infections. There was no significant difference between the two groups at the time of anesthesia, time of operation, or time of mobilization. There were significant differences between the two groups in the time of oral feeding (3.3±0.3 d in the Gastrografin group vs4.8±0.4 d in the control group; P = odds ratio--, 95%CI [-0.5 to +0.7 d]) and in the length of hospital stay (7.6±1.1 d in the Gastrografingroup vs10.2±1.3 d in the control group; P = odds ratio--, 95% CI

  5. Skin necrosis following extravasation of water soluble contrast media-report of 2 cases

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    Park, Jae Hyung; Kim, Seung Hyup; Shin, Myung Jin; Minn, Kyung Won; Park, Chul Kyu [College of Medicine, Seoul National University, Seoul (Korea, Republic of); Kim, Jong Chul [Kyung Sang Medical College, Jinju (Korea, Republic of)

    1987-08-15

    Two cases of skin necrosis following extravasation of contrast media for intravenous pyelography and computed tomography were experienced in the Department of Radiology, Seoul National University Hospital. The first case was 4 years old girl who suffered from known nephrotic syndrome. About 15cc of meglumine ioxitalamate (Telebrix 30) was injected through 25G needle at dorsum of left foot to visualize the urinary tract for renal biopsy. The 2nd case was 3 years old girl who suffered from seizure. About 12cc of meglumine ioxitalamate (Telebrix 30) was injected through 25G needle at dorsum of left foot. In both cases the dorsum of foot was swollen immediately after the extravastion of the contrast media. Following discoloration the skin showed vesicles with erythema. Consequently the skin showed white discoloration and ulcerated to form crust. In the former case, skin graft was applied successfully. However, in the latter, the lesion healed with only supportive dressings.

  6. Polysorbate 80 and low-osmolality water-soluble contrast medium enema in diagnosis and treatment of faecal obstruction in malignant phaeochromocytoma. Report of a case

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    Ratcliffe, J.F.

    Stercoral obstruction in a young woman with disseminated phaeochromocytoma was diagnosed and treated successfully using an enema of isosmolar iohexol (Omnipaque) and 1% polysorbate 80 (Tween 80) without complication. Surgical intervention was thus avoided. A low osmolality water-soluble contrast medium (iohexol 150 mg I/ml) with a wetting agent (1% Tween 80) was used because a barium suspension would have inspissated, exacerbating the constipation and a hyperosmolar contrast medium might have precipitated a hypertensive crisis and destablished her critical salt and water balance.

  7. Images in medicine: Diagnosis and pre-surgical triage of transanal rectal injury using multidetector CT with water-soluble contrast enema

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    Massimo Tonolini

    2013-01-01

    Full Text Available Transanal rectal injuries caused by foreign body insertion, sexual abuse, or iatrogenic procedures represent a very uncommon surgical emergency. Morbidity may be further increased by patient′s embarrassment and delayed presentation. Since management decisions largely depend on anatomic and severity assessment, multidetector Computed tomography with rectally administered water-soluble iodinated contrast medium is highly valuable to accurately depict traumatic rectal injuries, and to distinguish between intraperitoneal vs extraperitoneal injuries that require different surgical approaches.

  8. Activatable Water-Soluble Probes Enhance Tumor Imaging by Responding to Dysregulated pH and Exhibiting High Tumor-to-Liver Fluorescence Emission Contrast.

    Science.gov (United States)

    Xiong, Hu; Kos, Petra; Yan, Yunfeng; Zhou, Kejin; Miller, Jason B; Elkassih, Sussana; Siegwart, Daniel J

    2016-07-20

    Dysregulated pH has been recognized as a universal tumor microenvironment signature that can delineate tumors from normal tissues. Existing fluorescent probes that activate in response to pH are hindered by either fast clearance (in the case of small molecules) or high liver background emission (in the case of large particles). There remains a need to design water-soluble, long circulating, pH-responsive nanoprobes with high tumor-to-liver contrast. Herein, we report a modular chemical strategy to create acidic pH-sensitive and water-soluble fluorescent probes for high in vivo tumor detection and minimal liver activation. A combination of a modified Knoevenagel reaction and PEGylation yielded a series of NIR BODIPY fluorophores with tunable pKas, high quantum yield, and optimal orbital energies to enable photoinduced electron transfer (PeT) activation in response to pH. After intravenous administration, Probe 5c localized to tumors and provided excellent tumor-to-liver contrast (apparent T/L = 3) because it minimally activates in the liver. This phenomenon was further confirmed by direct ex vivo imaging experiments on harvested organs. Because no targeting ligands were required, we believe that this report introduces a versatile strategy to directly synthesize soluble probes with broad potential utility including fluorescence-based image-guided surgery, cancer diagnosis, and theranostic nanomedicine.

  9. Visual evoked response changes following intrathecal injection of water-soluble contrast media: a possible method of assessing neurotoxicity and a comparison of metrizamide and iopamidol.

    Science.gov (United States)

    Broadbridge, A T; Bayliss, S G; Firth, R; Farrell, G

    1984-09-01

    An investigation was carried out to ascertain if there was a change in visual evoked responses following the intrathecal injection of water-soluble contrast media for myeloradiculography and if this change provided an indication of neurotoxicity as assessed by the onset of headache during a period of 20 h following the radiological examination. The patients were unselected and examined, when facilities for measuring the visual evoked response were available, immediately before and at 1 and 20 h after the examination. Control readings were carried out before, 1 h and 20 h after lumbar puncture in patients who did not have an injection of contrast medium. The first 25 patients in the series received metrizamide; when iopamidol became available a change to the newer medium was made and iopamidol was used on all subsequent patients. All the injections were carried out by the same radiologist and the patients were kept in hospital overnight and interviewed the next morning, avoiding a specific reference to headache unless the patient denied all symptoms. It was found that the latency of the visual evoked response was affected in some cases by the presence of contrast medium in the cerebrospinal fluid and that there was a correlation between the severity of headaches and the delay in the visual evoked response at the 20 h post-myelogram measurement, but not at 1 h after the examination. It would appear, therefore, that the visual evoked response measurement is a valid method of assessing, in the short term, the neurotoxicity of intrathecal water-soluble contrast media and that, on this evidence, iopamidol is less neurotoxic than metrizamide. We are not aware of any long-term complications resulting from the use of either contrast medium.

  10. In vitro study on the anticoagulant effect of the water soluble contrast material: Diatrizoate, Ioxaglate and Iopromide

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    Lim, Duk; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of); Kim, Hak Soo; Park, Jae Hyung [Seoul National University Hospital, Seoul (Korea, Republic of)

    1989-12-15

    It has been reported that newly developed nonionic contrast material is less effective in anticoagulation than ionic contrast media. Anticoagulation properties were studied with high osmolar ionic contrast medium (diatrizoate), low osmolar ionic medium (ioxaglate) and low osmolar nonionic contrast medium (iopromide) as well as with normal saline for control. Arterial blood was taken from 10 adults before angiography. Two ml. of the arterial blood was introduced into the plastic syringes containing 2 cc. of each contrast medium and saline . The syrings were kept undisturbed in room temperature for 10 minutes, 30 minutes, 60 minutes, 90 minutes and then the blood contrast mixture was poured on the filter paper to detect the clots formed in the syrings. Delay of the clotting time was also checked in the contrast media with various concentrations of 100%, 30%, 10%, and 3%. Chi-square test of the data shows very significant difference in anticoagulation effect between the ionic group (diatrizoate, ioxzglate) and the nonionic one (iopromide). Clotting time in the nonionic medium (iopromide) was shorter in 30% concentration than that of the ionic material (diatrizoate, ioxaglate). Nonionic contrast medium (iopromide) has anticoagulation effect, but less effective than ionic media (diatrizoate, ioxaglate)

  11. Clinical analysis of contributors to the delayed gallbladder opacification following the use of water-soluble contrast medium

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    Ku MC

    2016-09-01

    Full Text Available Ming-Chang Ku,1,2 Victor C Kok,3,4 Ming-Yung Lee,5 Soa-Min Hsu,1 Pei-Yu Lee,1 Che-Wei Chang,1 Yeu-Sheng Tyan,6 Chi-Wen Juan7,8 1Department of Radiology, Kuang Tien General Hospital, Taichung, 2Department of Nursing, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli, 3Department of Internal Medicine, Division of Medical Oncology, Kuang Tien General Hospital, 4Department of Bioinformatics and Medical Engineering, Asia University, 5Department of Statistics and Informatics Science, Providence University, 6Department of Medical Imaging, Chung Shan Medical University Hospital, 7Department of Emergency Medicine, Kuang Tien General Hospital, 8Department of Nursing, HungKuang University, Taichung, Taiwan Objectives: Gallbladder opacification (GBO on computed tomography (CT imaging may obscure certain pathological or emergent conditions in the gallbladder, such as neoplasms, stones, and hemorrhagic cholecystitis. This study aimed to investigate the clinical contributing factors that could predict the presence of delayed GBO determined by CT.Methods: This study retrospectively evaluated 243 consecutive patients who received enhanced CT or intravenous pyelography imaging and then underwent abdominal CT imaging within 5 days. According to the interval between imaging, the patients were divided into group A (1 day, group B (2 or 3 days, and group C (4 or 5 days. Three radiologists evaluated CT images to determine GBO. Fisher’s exact test and multivariate backward stepwise elimination logistic regression were performed.Results: Positive GBO was significantly associated with the interval between imaging studies, contrast type, contrast volume, renal function, and hypertransaminasemia (P<0.05. Multivariate backward stepwise elimination logistic regression analysis of the three groups identified contrast type and hypertransaminasemia as independent predictors of GBO in group B patients (odds ratio [OR], 13.52, 95% confidence interval [CI

  12. Water-soluble cavitands - synthesis, solubilities and binding properties

    NARCIS (Netherlands)

    Middel, Oskar; Verboom, Willem; Reinhoudt, David N.

    2002-01-01

    Water-soluble cavitand receptors have been obtained by the introduction of ionizable groups (5, 21-28, 39) and neutral hydrophilic tetraethylene glycol based dendritic wedges (19, 20). The synthesis of these cavitands and a study of their water solubilities and binding properties toward neutral orga

  13. Water-soluble dopamine-based polymers for photoacoustic imaging

    NARCIS (Netherlands)

    Repenko, T.; Fokong, S.; De Laporte, L.; Go, D.; Kiessling, F.; Lammers, Twan Gerardus Gertudis Maria; Kuehne, A.

    2015-01-01

    Here we present a facile synthetic method yielding a linear form of polydopamine via Kumada-coupling, which can be converted into water-soluble melanin, generating high contrast in photoacoustic imaging.

  14. Oxidative potential of ambient water-soluble PM2.5 measured by Dithiothreitol (DTT) and Ascorbic Acid (AA) assays in the southeastern United States: contrasts in sources and health associations

    Science.gov (United States)

    Fang, T.; Verma, V.; Bates, J. T.; Abrams, J.; Klein, M.; Strickland, M. J.; Sarnat, S. E.; Chang, H. H.; Mulholland, J. A.; Tolbert, P. E.; Russell, A. G.; Weber, R. J.

    2015-11-01

    The ability of certain components of particulate matter to induce oxidative stress through catalytic 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 have recently developed a similar semi-automated system using the ascorbic acid (AA) assay. Approximately 500 PM2.5 filter samples collected in contrasting locations in the southeastern US were analyzed using both assays. We found that water-soluble DTT activity on a per air volume basis was more spatially uniform than water-soluble AA activity. DTT activity was higher in winter than in summer/fall, whereas AA activity was higher in summer/fall compared to winter, with highest levels near highly trafficked highways. DTT activity was correlated with organic and metal species, whereas AA activity was correlated with water-soluble metals (especially water-soluble Cu, r=0.70-0.91 at most sites). 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 secondary processes (e.g., organic aerosol oxidation or metal mobilization by formation of an aqueous particle with secondary acids) and traffic emissions to both DTT and AA activities in urban Atlanta. Biomass burning was a large source for DTT activity, but insignificant for AA. DTT activity was well correlated with PM2.5 mass (r=0.49-0.86 across sites/seasons), while AA activity did not co-vary strongly with mass. A linear model was developed to estimate DTT and AA activities for the central Atlanta Jefferson Street site, based on the CMB-E sources that are statistically significant with positive

  15. Oxidative potential of ambient water-soluble PM2.5 measured by Dithiothreitol (DTT and Ascorbic Acid (AA assays in the southeastern United States: contrasts in sources and health associations

    Directory of Open Access Journals (Sweden)

    T. Fang

    2015-11-01

    Full Text Available The ability of certain components of particulate matter to induce oxidative stress through catalytic 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 have recently developed a similar semi-automated system using the ascorbic acid (AA assay. Approximately 500 PM2.5 filter samples collected in contrasting locations in the southeastern US were analyzed using both assays. We found that water-soluble DTT activity on a per air volume basis was more spatially uniform than water-soluble AA activity. DTT activity was higher in winter than in summer/fall, whereas AA activity was higher in summer/fall compared to winter, with highest levels near highly trafficked highways. DTT activity was correlated with organic and metal species, whereas AA activity was correlated with water-soluble metals (especially water-soluble Cu, r=0.70–0.91 at most sites. 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 secondary processes (e.g., organic aerosol oxidation or metal mobilization by formation of an aqueous particle with secondary acids and traffic emissions to both DTT and AA activities in urban Atlanta. Biomass burning was a large source for DTT activity, but insignificant for AA. DTT activity was well correlated with PM2.5 mass (r=0.49–0.86 across sites/seasons, while AA activity did not co-vary strongly with mass. A linear model was developed to estimate DTT and AA activities for the central Atlanta Jefferson Street site, based on the CMB-E sources that are statistically significant with

  16. Water-soluble L-cysteine-coated FePt nanoparticles as dual MRI/CT imaging contrast agent for glioma.

    Science.gov (United States)

    Liang, Shuyan; Zhou, Qing; Wang, Min; Zhu, Yanhong; Wu, Qingzhi; Yang, Xiangliang

    2015-01-01

    Nanoparticles (NPs) are advantageous for the delivery of diagnosis agents to brain tumors. In this study, we attempted to develop an L-cysteine coated FePt (FePt-Cys) NP as MRI/CT imaging contrast agent for the diagnosis of malignant gliomas. FePt-Cys NPs were synthesized through a co-reduction route, which was characterized by transmission electron microscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and dynamic light scattering. The MRI and CT imaging ability of FePt-Cys NPs was evaluated using different gliomas cells (C6, SGH44, U251) as the model. Furthermore, the biocompatibility of the as-synthesized FePt-Cys NPs was evaluated using three different cell lines (ECV304, L929, and HEK293) as the model. The results showed that FePt-Cys NPs displayed excellent biocompatibility and good MRI/CT imaging ability, thereby indicating promising potential as a dual MRI/CT contrast agent for the diagnosis of brain malignant gliomas.

  17. Water-soluble l-cysteine-coated FePt nanoparticles as dual MRI/CT imaging contrast agent for glioma

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    Liang SY

    2015-03-01

    Full Text Available Shuyan Liang,1 Qing Zhou,1 Min Wang,2,3 Yanhong Zhu,1 Qingzhi Wu,2,3 Xiangliang Yang1 1College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 2State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, People’s Republic of China; 3Biomedical Material and Engineering Center of Hubei Province, Wuhan University of Technology, Wuhan, People’s Republic of China Abstract: Nanoparticles (NPs are advantageous for the delivery of diagnosis agents to brain tumors. In this study, we attempted to develop an l-cysteine coated FePt (FePt-Cys NP as MRI/CT imaging contrast agent for the diagnosis of malignant gliomas. FePt-Cys NPs were synthesized through a co-reduction route, which was characterized by transmission electron microscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and dynamic light scattering. The MRI and CT imaging ability of FePt-Cys NPs was evaluated using different gliomas cells (C6, SGH44, U251 as the model. Furthermore, the biocompatibility of the as-synthesized FePt-Cys NPs was evaluated using three different cell lines (ECV304, L929, and HEK293 as the model. The results showed that FePt-Cys NPs displayed excellent biocompatibility and good MRI/CT imaging ability, thereby indicating promising potential as a dual MRI/CT contrast agent for the diagnosis of brain malignant gliomas. Keywords: CT, glioma, MRI

  18. SOLUBILITY ENHANCEMENT OF POORLY WATER SOLUBLE DRUGS BY SOLID DISPERSIO

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    Amita Verm

    2012-01-01

    Full Text Available Solid dispersions have been employed to enhance the dissolution rates of poorly water-soluble drugs. Many approaches have been investigated for the preparation of solid dispersions. This paper reports the various solubility enhancement strategies in solid dispersion. The approaches described are fusion (melting, solvent evaporation, lyophilization (freeze drying, melt agglomeration process, extruding method, spray drying technology, use of surfactant, electro static spinning method and super critical fluid technology. This paper also highlights the potential applications and limitations of theseapproaches in solid dispersions.

  19. 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

    Science.gov (United States)

    Fang, Ting; Verma, Vishal; Bates, Josephine T.; Abrams, Joseph; Klein, Mitchel; Strickland, Matthew J.; Sarnat, Stefanie E.; Chang, Howard H.; Mulholland, James A.; Tolbert, Paige E.; Russell, Armistead G.; Weber, Rodney J.

    2016-03-01

    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 models were then used to estimate daily

  20. Water Soluble Polymers for Pharmaceutical Applications

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    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.

  1. Water-soluble polymers and compositions thereof

    Science.gov (United States)

    Smith, B.F.; Robison, T.W.; Gohdes, J.W.

    1999-04-06

    Water-soluble polymers including functionalization from the group of amino groups, carboxylic acid groups, phosphonic acid groups, phosphonic ester groups, acylpyrazolone groups, hydroxamic acid groups, aza crown ether groups, oxy crown ethers groups, guanidinium groups, amide groups, ester groups, aminodicarboxylic groups, permethylated polyvinylpyridine groups, permethylated amine groups, mercaptosuccinic acid groups, alkyl thiol groups, and N-alkylthiourea groups are disclosed.

  2. Characterization of Soluble Organics in Produced Water

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    Bostick, D.T.

    2002-01-16

    Soluble organics in produced water and refinery effluents represent treatment problems for the petroleum industry. Neither the chemistry involved in the production of soluble organics nor the impact of these chemicals on total effluent toxicity is well understood. The U.S. Department of Energy provides funding for Oak Ridge National Laboratory (ORNL) to support a collaborative project with Shell, Chevron, Phillips, and Statoil entitled ''Petroleum and Environmental Research Forum project (PERF 9844: Manage Water-Soluble Organics in Produced Water''). The goal of this project, which involves characterization and evaluation of these water-soluble compounds, is aimed at reducing the future production of such contaminants. To determine the effect that various drilling conditions might have on water-soluble organics (WSO) content in produced water, a simulated brine water containing the principal inorganic components normally found in Gulf of Mexico (GOM) brine sources was prepared. The GOM simulant was then contacted with as-received crude oil from a deep well site to study the effects of water cut, produced-water pH, salinity, pressure, temperature, and crude oil sources on the type and content of the WSO in produced water. The identities of individual semivolatile organic compounds (SVOCs) were determined in all as-received crude and actual produced water samples using standard USEPA Method (8270C) protocol. These analyses were supplemented with the more general measurements of total petroleum hydrocarbon (TPH) content in the gas (C{sub 6}-C{sub 10}), diesel (C{sub 10}-C{sub 20}), and oil (C{sub 20}-C{sub 28}) carbon ranges as determined by both gas chromatographic (GC) and infrared (IR) analyses. An open liquid chromatographic procedure was also used to differentiate the saturated hydrocarbon, aromatic hydrocarbon, and polar components within the extractable TPH. Inorganic constituents in the produced water were analyzed by ion

  3. Biochemical synthesis of water soluble conducting polymers

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    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.

  4. 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.

  5. Water soluble azido polyisocyanopeptides as functional β-sheet mimics

    NARCIS (Netherlands)

    Schwartz, Erik; Koepf, Matthieu; Kitto, Heather J.; Espelt, Mónica; Nebot-Carda, Vicent J.; Gelder, de Rene; Nolte, Roeland J.M.; Cornelissen, Jeroen J.L.M.; Rowan, Alan E.

    2009-01-01

    The design and synthesis of functional biomimetic water soluble polymers with a defined secondary structure has been developed using β-sheet polyisocyanopeptide scaffolds. Water soluble isocyanopolymers were prepared by random copolymerisation of the azido functionalized isocyanopeptides with nonfun

  6. Solubility Enhancement of a Poorly Water Soluble Drug by Forming Solid Dispersions using Mechanochemical Activation

    OpenAIRE

    Rojas-Oviedo, I.; Retchkiman-Corona, B.; Quirino-Barreda, C. T.; Cárdenas, J.; Schabes-Retchkiman, P. S.

    2012-01-01

    Mechanochemical activation is a practical cogrinding operation used to obtain a solid dispersion of a poorly water soluble drug through changes in the solid state molecular aggregation of drug-carrier mixtures and the formation of noncovalent interactions (hydrogen bonds) between two crystalline solids such as a soluble carrier, lactose, and a poorly soluble drug, indomethacin, in order to improve its solubility and dissolution rate. Samples of indomethacin and a physical mixture with a weigh...

  7. Nonlinear water waves with soluble surfactant

    Science.gov (United States)

    Lapham, Gary; Dowling, David; Schultz, William

    1998-11-01

    The hydrodynamic effects of surfactants have fascinated scientists for generations. This presentation describes an experimental investigation into the influence of a soluble surfactant on nonlinear capillary-gravity waves in the frequency range from 12 to 20 Hz. Waves were generated in a plexiglass wave tank (254 cm long, 30.5 cm wide, and 18 cm deep) with a triangular plunger wave maker. The tank was filled with carbon- and particulate-filtered water into which the soluble surfactant Triton-X-100® was added in known amounts. Wave slope was measured nonintrusively with a digital camera running at 225 fps by monitoring the position of light beams which passed up through the bottom of the tank, out through the wavy surface, and onto a white screen. Wave slope data were reduced to determine wave damping and the frequency content of the wave train. Both were influenced by the presence of the surfactant. Interestingly, a subharmonic wave occurring at one-sixth the paddle-driving frequency was found only when surfactant was present and the paddle was driven at amplitudes high enough to produce nonlinear waves in clean water. Although the origins of this subharmonic wave remain unclear, it appears to be a genuine manifestation of the combined effects of the surfactant and nonlinearity.

  8. CYCLODEXTRIN INCLUSION COMPLEX TO ENHANCE SOLUBILITY OF POORLY WATER SOLUBLE DRUGS: A REVIEW

    Directory of Open Access Journals (Sweden)

    V.B. Chaudhary * 1 and J. K. Patel 2

    2013-01-01

    Full Text Available Low solubility compounds show dissolution rate limited absorption and hence poor absorption, distribution and target organ delivery. Improvement of aqueous solubility in such a case is valuable goal to improve therapeutic efficacy. Complexation with CDs by different methods like physical mixing, melting, kneding, spray drying, freeze drying, co-evaporation has been reported to enhance the solubility, dissolution rate and bioavability of poorly water soluble drugs. The formation of inclusion complex can be confirmed by DSC, FTIR, XRD and SEM study. This review aims to assess the use of cyclodextrines as complexing agents to enhance the solubility of poorly soluble drugs and hence to resolve the many issues associated with developing and commercializing poorly water soluble drugs.

  9. Indomethacin solubility estimation in 1,4-dioxane + water mixtures by the extended hildebrand solubility approach

    Directory of Open Access Journals (Sweden)

    Miller A Ruidiaz

    2011-09-01

    Full Text Available Extended Hildebrand Solubility Approach (EHSA was successfully applied to evaluate the solubility of Indomethacin in 1,4-dioxane + water mixtures at 298.15 K. An acceptable correlation-performance of EHSA was found by using a regular polynomial model in order four of the W interaction parameter vs. solubility parameter of the mixtures (overall deviation was 8.9%. Although the mean deviation obtained was similar to that obtained directly by means of an empiric regression of the experimental solubility vs. mixtures solubility parameters, the advantages of EHSA are evident because it requires physicochemical properties easily available for drugs.

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

    African Journals Online (AJOL)

    SERVER

    2008-01-04

    Jan 4, 2008 ... Key words: Physical and ionic characteristics, heavy metals, water soluble fraction, crude oil and Azolla africana. ... impact on aquatic life (Camougis, 1981). Water ..... Fish, fisheries, aquatic macrophytes and water quality in.

  11. “ Enhancement of Solubility of poorly water soluble drug by solid dispersion technique”

    Directory of Open Access Journals (Sweden)

    V.R.Tagalpallewar

    2015-02-01

    Full Text Available Atovaquone and Satrinidazole has poor solubility resulting in low oral absorption hence low oral bioavailability. Hence to improve the solubility of poorly Atovaquone and Satrinidazole , hydrophilic polymers were used to enhance the dissolution by solid dispersion technique. Polyehylene Glycol 4000 and PVP k30 used to enhance the dissolution of both the drug by Solubilisation. Many alternative techniques have been used to improve such bioavailability; this study thus employed the simple solid dispersion technique and incorporated excipients which can increase the bioavailability of these drugs directly enhancing the dissolution rate of the drug and indirectly by reducing particle size.The aim of present work is to enhance the dissolution of poorly water soluble drug by using solid dispersion technique. To improve the dissolution rate, by using the various concentration of carrier or matrix with drug and hence ,improve the bioavailability of poorly water soluble drug by formulating solid dispersion.To enhance the solubility of poorly water soluble drug ,by means of solubilising agent. In case of poorly water soluble drug, dissolution may be the rate limiting step in the process of absorption. In such case ,we can improve their solubility and dissolution rate.To study the effect of surfactant on the solid dispersion of poorly water soluble drug.

  12. Solubility prediction of satranidazole in propylene glycol-water mixtures using extended hildebrand solubility approach

    Directory of Open Access Journals (Sweden)

    P B Rathi

    2011-01-01

    Full Text Available Extended Hildebrand solubility approach is used to estimate the solubility of satranidazole in binary solvent systems. The solubility of satranidazole in various propylene glycol-water mixtures was analyzed in terms of solute-solvent interactions using a modified version of Hildebrand-Scatchard treatment for regular solutions. The solubility equation employs term interaction energy (W to replace the geometric mean (δ1δ2 , where δ1 and δ2 are the cohesive energy densities for the solvent and solute, respectively. The new equation provides an accurate prediction of solubility once the interaction energy, W, is obtained. In this case, the energy term is regressed against a polynomial in δ1 of the binary mixture. A quartic expression of W in terms of solvent solubility parameter was found for predicting the solubility of satranidazole in propylene glycol-water mixtures. The expression yields an error in mole fraction solubility of ~3.74%, a value approximating that of the experimentally determined solubility. The method has potential usefulness in preformulation and formulation studies during which solubility prediction is important for drug design.

  13. Solubility prediction of satranidazole in propylene glycol-water mixtures using extended hildebrand solubility approach.

    Science.gov (United States)

    Rathi, P B

    2011-11-01

    Extended Hildebrand solubility approach is used to estimate the solubility of satranidazole in binary solvent systems. The solubility of satranidazole in various propylene glycol-water mixtures was analyzed in terms of solute-solvent interactions using a modified version of Hildebrand-Scatchard treatment for regular solutions. The solubility equation employs term interaction energy (W) to replace the geometric mean (δ(1)δ(2)), where δ(1) and δ(2) are the cohesive energy densities for the solvent and solute, respectively. The new equation provides an accurate prediction of solubility once the interaction energy, W, is obtained. In this case, the energy term is regressed against a polynomial in δ(1) of the binary mixture. A quartic expression of W in terms of solvent solubility parameter was found for predicting the solubility of satranidazole in propylene glycol-water mixtures. The expression yields an error in mole fraction solubility of ~3.74%, a value approximating that of the experimentally determined solubility. The method has potential usefulness in preformulation and formulation studies during which solubility prediction is important for drug design.

  14. Which Starch Fraction is Water-Soluble, Amylose or Amylopectin?

    Science.gov (United States)

    Green, Mark M.; And Others

    1975-01-01

    A survey of 22 popular organic chemistry textbooks showed that only four correctly stated that of the two components of starch, amylopectin is the water-soluble, and amylose is the water-insoluble. (MLH)

  15. Effect of Cyclodextrin Types and Co-Solvent on Solubility of a Poorly Water Soluble Drug

    Science.gov (United States)

    Charumanee, Suporn; Okonogi, Siriporn; Sirithunyalug, Jakkapan; Wolschann, Peter; Viernstein, Helmut

    2016-01-01

    The aim of the study was to investigate the solubility of piroxicam (Prx) depending on the inclusion complexation with various cyclodextrins (CDs) and on ethanol as a co-solvent. The phase-solubility method was applied to determine drug solubility in binary and ternary systems. The results showed that in systems consisting of the drug dissolved in ethanol–water mixtures, the drug solubility increased exponentially with a rising concentration of ethanol. The phase solubility measurements of the drug in aqueous solutions of CDs, β-CD and γ-CD exhibited diagrams of AL-type, whereas 2,6-dimethyl-β-CD revealed AP-type. The destabilizing effect of ethanol as a co-solvent was observed for all complexes regardless of the CD type, as a consequence of it the lowering of the complex formation constants. In systems with a higher concentration of ethanol, the drug solubility was increased in opposition to the decreasing complex formation constants. According to this study, the type of CDs played a more important role on the solubility of Prx, and the use of ethanol as a co-solvent exhibited no synergistic effect on the improvement of Prx solubility. The Prx solubility was increased again due to the better solubility in ethanol. PMID:27763573

  16. Effect of Cyclodextrin Types and Co-Solvent on Solubility of a Poorly Water Soluble Drug

    Directory of Open Access Journals (Sweden)

    Suporn Charumanee

    2016-10-01

    Full Text Available The aim of the study was to investigate the solubility of piroxicam (Prx depending on the inclusion complexation with various cyclodextrins (CDs and on ethanol as a co-solvent. The phase-solubility method was applied to determine drug solubility in binary and ternary systems. The results showed that in systems consisting of the drug dissolved in ethanol–water mixtures, the drug solubility increased exponentially with a rising concentration of ethanol. The phase solubility measurements of the drug in aqueous solutions of CDs, β-CD and γ-CD exhibited diagrams of AL-type, whereas 2,6-dimethyl-β-CD revealed AP-type. The destabilizing effect of ethanol as a co-solvent was observed for all complexes regardless of the CD type, as a consequence of it the lowering of the complex formation constants. In systems with a higher concentration of ethanol, the drug solubility was increased in opposition to the decreasing complex formation constants. According to this study, the type of CDs played a more important role on the solubility of Prx, and the use of ethanol as a co-solvent exhibited no synergistic effect on the improvement of Prx solubility. The Prx solubility was increased again due to the better solubility in ethanol.

  17. Enhancement of solubility and dissolution rate of poorly water soluble raloxifene using microwave induced fusion method

    OpenAIRE

    Payal Hasmukhlal Patil; Veena Sailendra Belgamwar; Pratibha Ramratan Patil; Sanjay Javerilal Surana

    2013-01-01

    The objective of the present work was to enhance the solubility and dissolution rate of the drug raloxifene HCl (RLX), which is poorly soluble in water. The solubility of RLX was observed to increase with increasing concentration of hydroxypropyl methylcellulose (HPMC E5 LV). The optimized ratio for preparing a solid dispersion (SD) of RLX with HPMC E5 LV using the microwave-induced fusion method was 1:5 w/w. Microwave energy was used to prepare SDs. HPMC E5 LV was used as a hydrophilic carri...

  18. 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...... the concentrations reached are typically below the limit of detection. The following guidelines were established: for compounds with Sapp >1 mg/mL, the disc method is recommended. For compounds with Sapp

  19. 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...

  20. Deep cavitand receptors with pH-independent water solubility.

    Science.gov (United States)

    Lledó, Agustí; Rebek, Julius

    2010-12-07

    Pendant oligoethyleneglycol groups confer water solubility to a cavitand over a wide pH range. The kinetic stability of the host-guest complexes reveals an effective stabilization through hydrogen bonding even in the highly competitive aqueous environment.

  1. Water-soluble pyrrolopyrrole cyanine (PPCy) NIR fluorophores.

    Science.gov (United States)

    Wiktorowski, Simon; Rosazza, Christelle; Winterhalder, Martin J; Daltrozzo, Ewald; Zumbusch, Andreas

    2014-05-11

    Water-soluble derivatives of pyrrolopyrrole cyanines (PPCys) have been synthesized by a post-synthetic modification route. In highly polar media, these dyes are excellent NIR fluorophores. Labeling experiments show how these novel dyes are internalized into mammalian cells.

  2. Plasma concentrations of water-soluble vitamins in metabolic ...

    African Journals Online (AJOL)

    2012-01-21

    Jan 21, 2012 ... levels of water-soluble vitamins with metabolic syndrome and its various components. Aims: This ... thiamine has a role in reducing cellular oxidative stress.[2,12] ... a protective effect on pancreatic beta-cell survival, probably.

  3. Improved water solubility of neohesperidin dihydrochalcone in sweetener blends.

    Science.gov (United States)

    Benavente-García, O; Castillo, J; Del Baño, M J; Lorente, J

    2001-01-01

    Significant technological advantages in terms of sweetness synergy and hence cost-saving can be obtained if neohesperidin dihydrochalcone (NHDC) is used in sweetener blends with other intense or bulk sweeteners. The combination of NHDC with sodium saccharin or sodium cyclamate is an excellent method to improve the water solubility at room temperature of NHDC. In the case of NHDC-sodium saccharin, two different methods for blend preparation, a simple mixture and a cosolubilized mixture, can be used, with similar results obtained for solubility and solution stability properties. To improve temporally the water solubility of NHDC in combination with sodium cyclamate, it is absolutely necessary to prepare cosolubilized blends.

  4. Water sorption and solubility of polyamide denture base materials.

    Science.gov (United States)

    Nguyen, Long G; Kopperud, Hilde M; Øilo, Marit

    2017-01-01

    Purpose: Some patients experience adverse reactions to poly(methyl methacrylate)-based (PMMA) dentures. Polyamide (PA) as an alternative to PMMA has, however, not been well documented with regard to water sorption and water solubility. The aim of this in vitro study was to measure water sorption and water solubility of two PA materials compared with PMMA, and to evaluate the major components released from the PA materials and the effect on hardness of the materials. Methods: Ten discs (40.0 mm diameter, 2.0 mm thick) of each material (PA: Valplast and Breflex; PMMA: SR Ivocap HIP) were prepared according to manufacturers' recommendations. The specimens were tested for water sorption and water solubility, according to a modification of ISO 20795-1:2008. Released substances were analysed by gas chromatography/mass spectrometry (GC/MS). Results: There were statistically significant differences among the materials regarding water sorption, water solubility and time to water saturation. Breflex had the highest water sorption (30.4 μg/mm(3)), followed by PMMA-material (25.8 μg/mm(3)) and Valplast (13.6 μg/mm(3)). Both PA materials had statistically significant lower water solubility than the PMMA. Both PA had a net increase in weight. Analysis by GC/MS identified release of the compound 12-aminododecanolactam from the material Valplast. No release was found from the Breflex material. Conclusions: The PA denture materials show differences in water sorption and solubility, but within the limits of the standard requirements. The PA showed a net increase in weight after long-term water sorption. The clinical implications of the findings are not elucidated.

  5. 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

    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 1:4:0.5 resulted in a particle size of amorphous state. It demonstrated the highest solubility (32.51±2.41 μg/mL), an excellent dissolution (~85% in 10 minutes), and an oral bioavailability ~2.5-fold better than that of the free drug. It showed similar oral bioavailability compared to the conventional solid dispersion. Conclusion Electrosprayed nanospherules, which provide improved solubility and bioavailability, are promising drug delivery tools for oral administration of poorly water-soluble fenofibrate. PMID:26834471

  6. Solubility Enhancement of a Poorly Water Soluble Drug by Forming Solid Dispersions using Mechanochemical Activation

    Science.gov (United States)

    Rojas-Oviedo, I.; Retchkiman-Corona, B.; Quirino-Barreda, C. T.; Cárdenas, J.; Schabes-Retchkiman, P. S.

    2012-01-01

    Mechanochemical activation is a practical cogrinding operation used to obtain a solid dispersion of a poorly water soluble drug through changes in the solid state molecular aggregation of drug-carrier mixtures and the formation of noncovalent interactions (hydrogen bonds) between two crystalline solids such as a soluble carrier, lactose, and a poorly soluble drug, indomethacin, in order to improve its solubility and dissolution rate. Samples of indomethacin and a physical mixture with a weight ratio of 1:1 of indomethacin and lactose were ground using a high speed vibrating ball mill. Particle size was determined by electron microscopy, the reduction of crystallinity was determined by calorimetry and transmission electron microscopy, infrared spectroscopy was used to find evidence of any interactions between the drug and the carrier and the determination of apparent solubility allowed for the corroboration of changes in solubility. Before grinding, scanning electron microscopy showed the drug and lactose to have an average particle size of around 50 and 30 μm, respectively. After high speed grinding, indomethacin and the mixture had a reduced average particle size of around 5 and 2 μm, respectively, showing a morphological change. The ground mixture produced a solid dispersion that had a loss of crystallinity that reached 81% after 30 min of grinding while the drug solubility of indomethacin within the solid dispersion increased by 2.76 fold as compared to the pure drug. Drug activation due to hydrogen bonds between the carboxylic group of the drug and the hydroxyl group of lactose as well as the decrease in crystallinity of the solid dispersion and the reduction of the particle size led to a better water solubility of indomethacin. PMID:23798775

  7. Solubilities of Isophthalic Acid in Acetic Acid + Water Solvent Mixtures

    Institute of Scientific and Technical Information of China (English)

    CHENG Youwei; HUO Lei; LI Xi

    2013-01-01

    The solubilities of isophthalic acid (1) in binary acetic acid (2) + water (3) solvent mixtures were determined in a pressurized vessel.The temperature range was from 373.2 to 473.2K and the range of the mole fraction of acetic acid in the solvent mixtures was from x2 =0 to 1.A new method to measure the solubility was developed,which solved the problem of sampling at high temperature.The experimental results indicated that within the temperature range studied,the solubilities of isophthalic acid in all mixtures showed an increasing trend with increasing temperature.The experimental solubilities were correlated by the Buchowski equation,and the calculate results showed good agreement with the experimental solubilities.Furthermore,the mixed solvent systems were found to exhibit a maximum solubility effect on the solubility,which may be attributed to the intermolecular association between the solute and the solvent mixture.The maximum solubility effect was well modeled by the modified Wilson equation.

  8. Water sorption/solubility of dental adhesive resins.

    Science.gov (United States)

    Malacarne, Juliana; Carvalho, Ricardo M; de Goes, Mario F; Svizero, Nadia; Pashley, David H; Tay, Franklin R; Yiu, Cynthia K; Carrilho, Marcela Rocha de Oliveira; de Oliveira Carrilho, Marcela Rocha

    2006-10-01

    This study evaluated the water sorption, solubility and kinetics of water diffusion in commercial and experimental resins that are formulated to be used as dentin and enamel bonding agents. Four commercial adhesives were selected along with their solvent-monomer combination: the bonding resins were of Adper Scotchbond Multi-Purpose (MP) and Clearfil SE Bond (SE) systems, and the "one-bottle" systems, Adper Single Bond (SB) and Excite (EX). Five experimental methacrylate-based resins of known hydrophilicities (R1, R2, R3, R4 and R5) were used as reference materials. Specimen disks were prepared by dispensing the uncured resin into a mould (5.8mm x 0.8mm). After desiccation, the cured specimens were weighed and then stored in distilled water for evaluation of the water diffusion kinetics over a 28-day period. Resin composition and hydrophilicity (ranked by their Hoy's solubility parameters) influenced water sorption, solubility and water diffusion in both commercial and experimental dental resins. The most hydrophilic experimental resin, R5, showed the highest water sorption, solubility and water diffusion coefficient. Among the commercial adhesives, the solvated systems, SB and EX, showed water sorption, solubility and water diffusion coefficients significantly greater than those observed for the non-solvated systems, MP and SE (p<0.05). In general, the extent and rate of water sorption increased with the hydrophilicity of the resin blends. The extensive amount of water sorption in the current hydrophilic dental resins is a cause of concern. This may affect the mechanical stability of these resins and favor the rapid and catastrophic degradation of resin-dentin bonds.

  9. Enhancement of solubility and dissolution rate of poorly water soluble raloxifene using microwave induced fusion method

    Directory of Open Access Journals (Sweden)

    Payal Hasmukhlal Patil

    2013-09-01

    Full Text Available The objective of the present work was to enhance the solubility and dissolution rate of the drug raloxifene HCl (RLX, which is poorly soluble in water. The solubility of RLX was observed to increase with increasing concentration of hydroxypropyl methylcellulose (HPMC E5 LV. The optimized ratio for preparing a solid dispersion (SD of RLX with HPMC E5 LV using the microwave-induced fusion method was 1:5 w/w. Microwave energy was used to prepare SDs. HPMC E5 LV was used as a hydrophilic carrier to enhance the solubility and dissolution rate of RLX. After microwave treatment, the drug and hydrophilic polymer are fused together, and the drug is converted from the crystalline form into an amorphous form. This was confirmed through scanning electron microscopy (SEM, differential scanning calorimetry (DSC and powder X-ray diffraction (PXRD studies. These results suggested that the microwave method is a simple and efficient method of preparing SDs. The solubility and dissolution rate of the SDs were increased significantly compared with pure RLX due to the surfactant and wetting properties of HPMC E5 LV and the formation of molecular dispersions of the drug in HPMC E5 LV. It was concluded that the solubility and dissolution rate of RLX are increased significantly when an SD of the drug is prepared using the microwave-induced fusion method.

  10. Phosphoryl choline-grafted water-soluble carbon nanotube

    Institute of Scientific and Technical Information of China (English)

    Tao Zhang; Kai Xi; Min Gu; Zheng Sheng Jiang

    2008-01-01

    Water-soluble property is the precondition of biomedical evaluation and application of carbon nanotube (CNT). Novel watersoluble CNT was synthesized in this letter by grafting phosphoryi choline (PC) onto multi-wall CNTs. Utilizing FTIR, XPS, TGAand TEM, the title CNTs were characterized and it was found that the target products could facilely dissolve in water.

  11. Efficient and Convenient Preparation of Water-Soluble Fullerenol

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-Min章建民; YANG Wen杨文; HE Ping何萍; ZHU Shi-Zheng朱士正

    2004-01-01

    An efficient and convenient preparation of fullerenols was described. With polyethylene glycol (PEG) 400 as catalyst, fullerenols were conveniently synthesized via the direct reaction of fullerene with aqueous NaOH. By control of reaction conditions, either water-soluble C60 fullerenol or water-insoluble C60 fullerenol could be obtained selectively.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gunning, D.B.; Barua, A.B.; Olson, J.A. (Iowa State Univ., Ames (United States))

    1990-02-26

    Retinoyl {beta}-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 {beta}-glucuronide, retinoyl {beta}-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.

  13. 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

  14. Study of pH-dependent drugs solubility in water

    Directory of Open Access Journals (Sweden)

    Pobudkowska A.

    2014-01-01

    Full Text Available The solubilities of five sparingly soluble drug-compounds in water have been measured at constant temperatures (298.1K and 310.1K by the classical saturation shake-flask method. All substances presented in this work are derivatives of anthranilic acid: flufenamic acid, (FLU, mefenamic acid, (MEF, niflumic acid, (NIF, diclofenac sodium, (DIC, and meclofenamic sodium, (MEC. All of them have anti-inflammatory action. Since the aqueous solubility of the ionized drug is significantly higher than the unionized, the experimental conditions that affect equilibrium solubility values such as composition of aqueous buffer have been examined. The Henderson-Hasselbalch (HH relationship has been used to predict the pH-dependent solubility profiles of chosen drugs at two temperatures. For this purpose the pKa values of the investigated drugs have been determined with Bates-Schwarzenbach spectrophotometric method at temperature 310.1 K. At temperature 298.1K these values were reported earlier. Similar values of pKa were obtained from the solubility measurements.

  15. Water-Soluble Gold Nanoparticles Protected by Fluorinated Amphiphilic Thiolates

    NARCIS (Netherlands)

    Gentilini, Cristina; Evangelista, Fabrizio; Rudolf, Petra; Franchi, Paola; Lucarini, Marco; Pasquato, Lucia

    2008-01-01

    The preparation and the properties of gold nanoparticles (Au NPs) protected by perfluorinated amphiphiles are described. The thiols were devised to form a perfluorinated region close to the gold surface and to have a hydrophilic portion in contact with the bulk solvent to impart solubility in water.

  16. 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 ... central area and major road systems and possible aerosol sources include biomass ..... Tanzania than at European rural sites32 and Asia.33,34. To determine the ...

  17. 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.

  18. Water-soluble constituents of cumin: monoterpenoid glucosides.

    Science.gov (United States)

    Ishikawa, Toru; Takayanagi, Tomomi; Kitajima, Junichi

    2002-11-01

    From the water-soluble portion of the methanol extract of cumin (fruit of Cuminum cyminum L.), which has been used as a spice and medicine since antiquity, sixteen monoterpenoid glucosides, including twelve new compounds, were isolated. Their structures were clarified by spectral investigation.

  19. Morphological Analysis and Solubility of Lead Particles: Effect of Phosphates and Implications to Drinking Water (Presentation)

    Science.gov (United States)

    Describe lead synthesis experiments conduced to model the impact of water quality on lead particles and solubility Develop a model system that can be used for lead solubility studies Understand how phosphates impact morphology and solubility transformations with time

  20. Mechanisms and solubility equations of gas dissolving in water

    Institute of Scientific and Technical Information of China (English)

    付晓泰; 王振平; 卢双舫

    1996-01-01

    The two mechanisms of gas dissolving in water, interstice filling and aquation, are proposed. General equations of gas solubility have been deduced from the mechanisms and experimental observations. Dependence of Henry’s coefficient on temperature, pressure, aquation equilibrium constant and gas molecular wlume is discussed. The theoretical equations were verified by experimental data, which shows that the theoretical results of the solubility of methane are in good agreement with the experimental data in the range of 20 -160℃ and under a pressure of less than 60 MPa.

  1. Formulation of a Novel Nanoemulsion System for Enhanced Solubility of a Sparingly Water Soluble Antibiotic, Clarithromycin

    Directory of Open Access Journals (Sweden)

    Stuti Vatsraj

    2014-01-01

    Full Text Available The sparingly water soluble property of majority of medicinally significant drugs acts as a potential barrier towards its utilization for therapeutic purpose. The present study was thus aimed at development of a novel oil-in-water (o/w nanoemulsion (NE system having ability to function as carrier for poorly soluble drugs with clarithromycin as a model antibiotic. The therapeutically effective concentration of clarithromycin, 5 mg/mL, was achieved using polysorbate 80 combined with olive oil as lipophilic counterion. A three-level three-factorial central composite experimental design was utilized to conduct the experiments. The effects of selected variables, polysorbate 80 and olive oil content and concentration of polyvinyl alcohol, were investigated. The particle size of clarithromycin for the optimized formulation was observed to be 30 nm. The morphology of the nanoemulsion was explored using transmission electron microscopy (TEM. The emulsions prepared with the optimized formula demonstrated good physical stability during storage at room temperature. Antibacterial activity was conducted with the optimized nanoemulsion NESH 01 and compared with free clarithromycin. Zone of inhibition was larger for NESH 01 as compared to that with free clarithromycin. This implies that the solubility and hence the bioavailability of clarithromycin has increased in the formulated nanoemulsion system.

  2. OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER

    Energy Technology Data Exchange (ETDEWEB)

    Klasson, KT

    2002-03-14

    This project was an extension of previous research to improve the applicability of ozonation and will help address the petroleum-industry problem of treating produced water containing soluble organics. The goal of this project was to maximize oxidation of hexane-extractable organics during a single-pass operation. The project investigated: (1) oxidant production by electrochemical and sonochemical methods, (2) increasing the mass transfer rate in the reactor by forming microbubbles during ozone injection into the produced water, and (3) using ultraviolet irradiation to enhance the reaction if needed. Several types of methodologies for treatment of soluble organics in synthetic and actual produced waters have been performed. The technologies tested may be categorized as follows: (1) Destruction via sonochemical oxidation at different pH, salt concentration, ultraviolet irradiation, and ferrous iron concentrations. (2) Destruction via ozonation at different pH, salt concentration, hydrogen peroxide concentrations, ultraviolet irradiation, temperature, and reactor configurations.

  3. Solubility effects in waste-glass/demineralized-water systems

    Energy Technology Data Exchange (ETDEWEB)

    Fullam, H.T.

    1981-06-01

    Aqueous systems involving demineralized water and four glass compositions (including standins for actinides and fission products) at temperatures of up to 150/sup 0/C were studied. Two methods were used to measure the solubility of glass components in demineralized water. One method involved approaching equilibrium from subsaturation, while the second method involved approaching equilibrium from supersaturation. The aqueous solutions were analyzed by induction-coupled plasma spectrometry (ICP). Uranium was determined using a Scintrex U-A3 uranium analyzer and zinc and cesium were determined by atomic absorption. The system that results when a waste glass is contacted with demineralized water is a complex one. The two methods used to determine the solubility limits gave very different results, with the supersaturation method yielding much higher solution concentrations than the subsaturation method for most of the elements present in the waste glasses. The results show that it is impossible to assign solubility limits to the various glass components without thoroughly describing the glass-water systems. This includes not only defining the glass type and solution temperature, but also the glass surface area-to-water volume ratio (S/V) of the system and the complete thermal history of the system. 21 figures, 22 tables. (DLC)

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

    DEFF Research Database (Denmark)

    Lind, Marianne Ladegaard

    in the development of lipid-based formulations. However, in order for optimum formulations to be developed, knowledge of the mechanisms of absorption of poorly water-soluble drug substances is desired. Accordingly, the purpose of this PhD study was to study the effects of endogenous surfactants (bile salts...... the intake of a lipid-rich meal can increase the bioavailability due to slower gastric emptying, increased solubilization of the drug substance in the intestinal fluids by endogenous and exogenous components, inhibition of efflux carriers and induction of intestinal lymphatic transport. Some...... of these processes can also be obtained by formulating the poorly water-soluble drug substances in lipid-based formulations. Then the drug substance is in solution when administered. Consequently, an enhanced and less variable bioavailability can be obtained, and this has led to an increasing interest...

  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.

  6. Solubility and aggregation of Gly(5) in water.

    Science.gov (United States)

    Karandur, Deepti; Wong, Ka-Yiu; Pettitt, B Montgomery

    2014-08-14

    Experimentally, the solubility of oligoglycines in water decreases as its length increases. Computationally, the free energy of solvation becomes more favorable with chain length for short (n = 1-5) oligoglycines. We present results of large scale simulations with over 600 pentaglycines at varying concentrations in explicit solvent to consider the mechanism of aggregation. The solubility limit of Gly5 for the force field used was calculated and compared with experimental values. We find that intermolecular interactions between pentaglycines are favored over interactions between glycine and water, leading to their aggregation. However, the interaction driving peptide associations, liquid-liquid phase separation, are not predominantly hydrogen bonding. Instead, non-hydrogen bonding interactions between partially charged atoms on the peptide backbone allow the formation of dipole-dipole and charge layering correlations that mechanistically stabilize the formation of large, stable peptide clusters.

  7. New water-soluble carbamate ester derivatives of resveratrol

    OpenAIRE

    Andrea Mattarei; Massimo Carraro; Michele Azzolini; Cristina Paradisi; Mario Zoratti; Lucia Biasutto

    2014-01-01

    Low bioavailability severely hinders exploitation of the biomedical potential of resveratrol. Extensive phase-II metabolism and poor water solubility contribute to lowering the concentrations of resveratrol in the bloodstream after oral administration. Prodrugs may provide a solution—protection of the phenolic functions hinders conjugative metabolism and can be exploited to modulate the physicochemical properties of the compound. We report here the synthesis and characterization of carb...

  8. Water Soluble Iron aminoclay for Catalytic Reduction of Nitrophenol

    Directory of Open Access Journals (Sweden)

    S. ANBU ANJUGAM VANDARKUZHALI

    2013-06-01

    Full Text Available Water soluble iron decorated phyllosilicate is synthesized through one pot sol-gel synthesis by a wet chemical method using NaBH4 as reducing agent. The as-synthesized nanocomposite is characterized by powder-XRD and TGA techniques. The morphology of the composite is obtained using HRSEM and HRTEM. The prepared nanocomposite is an efficient catalyst for the reduction of nitrophenol.

  9. 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.

  10. 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.

  11. Hybrid solar cells from water-soluble polymers

    Directory of Open Access Journals (Sweden)

    James T. McLeskey

    2006-01-01

    Full Text Available We report on the use of a water-soluble, light-absorbing polythiophene polymer to fabricate novel photovoltaic devices. The polymer is a water-soluble thiophene known as sodium poly[2-(3-thienyl-ethoxy-4-butylsulfonate] or PTEBS. The intention is to take advantage of the properties of conjugated polymers (flexible, tunable, and easy to process and incorporate the additional benefits of water solubility (easily controlled evaporation rates and environmentally friendly. The PTEBS polythiophene has shown significant photovoltaic response and has been found to be effective for making solar cells. To date, solar cells in three different configurations have been produced: titanium dioxide (TiO2 bilayer cells, TiO2 bulk heterojunction solar cells, and carbon nanotubes (CNTs in bulk heterojunctions. The best performance thus far has been achieved with TiO2 bilayer devices. These devices have an open circuit voltage (Voc of 0.84V, a short circuit current (Jsc of 0.15 mA/cm2, a fill factor (ff of 0.91, and an efficiency (η of 0.15 %.

  12. 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.

  13. Synthesis and properties of water-soluble asterisk molecules.

    Science.gov (United States)

    Menger, Fredric M; Azov, Vladimir A

    2002-09-18

    An asterisk is comprised of six semirigid arms projecting from a benzene nucleus. In the case at hand, asterisks were synthesized with one, two, or three aromatic rings (connected by sulfur atoms) in each of the six arms. A phosphomonoester at the termini of each arm solubilized the asterisks in water. The colloidal properties of these amphiphilic molecules were investigated by UV-vis and fluorescence spectroscopy, calorimetry, light scattering, surface tensiometry, and pulse-gradient spin-echo NMR. Solubility, solubilization, metal binding, and micelle "seeding" experiments were also carried out. Chain-conformation and supramolecular assembly into remarkable molecular "scrolls" were investigated by X-ray analysis and electron microscopy, respectively. One of the more interesting properties of the asterisks is that they remain monomeric in water despite having as many as 19 hydrophobic aromatic rings exposed to the water. The reasons for this behavior, and the possibility of exploiting it for constructing enzyme models free from aggregation equilibria, are discussed.

  14. Effects of sulfite ions on water-soluble chlorophyll proteins

    Energy Technology Data Exchange (ETDEWEB)

    Sugahara, K.; Uchida, S.; Takimoto, M.

    1980-01-01

    To clarify the mechanisms and processes of chlorophyll destruction and the relation to the appearance of visible symptoms in SO/sub 2/-injured plants, model experiments were carried out by utilizing the peculiar properties of a water-soluble chlorophyll protein from Chenopodium album. The acceleration of chlorophyll destruction by sulfite ions under aerobic and illuminated conditions, reported previously in organic solvent, was not observed for the water-soluble pigment-protein complex, even in 4 x 10/sup -2/ M sulfite. This indicates that pigments are stabilized by combining with protein molecules. On comparison of pigment destruction between the reconstituted chlorophyll a- and chlorophyllide a-proteins in the presence of sulfite ions, the former was slightly sensitive to sulfite ions. On the other hand, it was demonstrated that photoconversion of water-soluble chlorophyll protein was inhibited by denaturation of the protein moiety caused by sulfite ions in the presence of light. In addition it was shown that it was necessary for the pigment absorbing the light energy to be structurally related to the protein moiety for inhibition of photoconversion. From these results, the inhibition processes of photoconversion are inferred as follows: conformational changes of apoprotein molecules were induced by light energy absorbed by the pigments and which allowed sulfite ions to attack the apoprotein molecules. The mechanism of the sulfite action on the apoprotein is the breakdown of disulfide bonds in proteins, the disulfide bonds having important functions in the photoconversion process. From the present model experiments, it is suggested that the breakdown of disulfide bonds occurred and induced damage to the chloroplast lamellae or physiological functions in the SO/sub 2/-injured plant tissues. 17 references, 8 figures.

  15. [Mutagen properties of water-soluble polysaccharides from Acorus calamus].

    Science.gov (United States)

    Gur'ev, A M; Belousov, M B; Akhmedzhanov, R R; Iusubov, M S; Voronova, O L; Karpova, G V; Churin, A A

    2010-08-01

    Mutagenic properties of water soluble polysaccharides (WSPS) extracted from Acorus calamus L. have been studied. Neither a single intravenous injection nor a course intraperitoneal introduction of WSPS in a dose of 1/2 LD50 to mice of the CBA/CaLac line increases the level of cytogenetic disorders in the bone marrow cells. The investigation of WSPS by means of the somatic mosaicism test showed that the given dose of WSPS does not increase the rate of mutant spots on Drosophila wings.

  16. Water-soluble constituents from aerial roots of Ficus microcarpa.

    Science.gov (United States)

    Ouyang, M-A; Kuo, Y-H

    2006-01-01

    Three new water-soluble constituents [ficuscarpanoside B (1), (7E,9Z)-dihydrophaseic acid 3-O-beta-D-glucopyranoside (4) and ficuscarpanic acid (6)] and the natural product 2,2'-dihydroxyl ether (7) have been isolated, together with three known compounds [(7S,8R)-syringoylglycerol (2), (7S,8R)-syringoylglycerol-7-O-beta-D-glucopyranoside (3) and icariside D2 (5)] from the aerial roots of Ficus microcarpa. Identification of their structures was achieved by 1D and 2D NMR experiments, including 1H-1H COSY, NOESY, HMQC and HMBC methods and FAB mass spectral data.

  17. Zwitterionic phosphorylcholine-protected water-soluble nanoparticles

    Institute of Scientific and Technical Information of China (English)

    JIN Qiao; LIU XiangSheng; XU JianPing; JI Jian; SHEN JiaCong

    2009-01-01

    The water-soluble Ag nanoparticles capped with novel zwitterionic thioalkylated phosphorylcholine were synthesized. The Ag nanoparticles showed remarkable stability in saline media with salt concen-trations as high as 2.0 mol/L and plasma using UV-vis absorption spectroscopy. Similarly, compared with tiopronin and citrate-protected Ag nanoparticles, the zwitterionic phosphorylcholine Ag nanopar-ticles did not precipitate out of solution when charged polyelectrolytes or biopolymers were added. The zwitterionic phosphorylcholine might be a better ligand for stabilizing metal nanoparticles.

  18. Zwitterionic phosphorylcholine-protected water-soluble Ag nanoparticles

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The water-soluble Ag nanoparticles capped with novel zwitterionic thioalkylated phosphorylcholine were synthesized.The Ag nanoparticles showed remarkable stability in saline media with salt concen-trations as high as 2.0 mol/L and plasma using UV-vis absorption spectroscopy.Similarly,compared with tiopronin and citrate-protected Ag nanoparticles,the zwitterionic phosphorylcholine Ag nanopar-ticles did not precipitate out of solution when charged polyelectrolytes or biopolymers were added.The zwitterionic phosphorylcholine might be a better ligand for stabilizing metal nanoparticles.

  19. Preparation and Properties of Water-soluble Conjugated Polyelectrolyte

    Institute of Scientific and Technical Information of China (English)

    BAO Xiangjun; HONG Ruibin; HU Jianhua; ZHONG Yiping; LIU Ping; DENG Wenji

    2014-01-01

    The water-soluble conjugated polyelectrolyte, poly[3-(1′-ethyloxy-2′-N- methylimidazole) thiophene] (PEOIMT), was prepared. Its photophysical and electrochemical properties, and response characteristics to the external condition (e g, temperature response, solvent response and pH response), were investigated. The results show the PEOIMT belongs to the organic semiconductor. The interaction between the PEOIMT and the bovine serum albumin (BSA) was investigated using UV-vis spectroscopy. It was found that the PEOIMT could interact with the BSA. The PEOIMT can be used as a biosensor to detect the BSA.

  20. Wettability, water sorption and water solubility of seven silicone elastomers used for maxillofacial prostheses.

    Science.gov (United States)

    Hulterström, Anna Karin; Berglund, Anders; Ruyter, I Eystein

    2008-01-01

    The wettability, water sorption and solubility of silicone elastomers used for maxillofacial prostheses were studied. The hypothesis was, that a material that has absorbed water would show an increase in the wettability and thus also the surface free energy of the material. Seven silicone elastomers, both addition- and condensation type polymers, were included. Five specimens of each material were subjected to treatment according to ISO standards 1567:1999 and 10477: 2004 for water sorption and solubility. The volumes of the specimens were measured according to Archimedes principle. The contact angle was measured with a contact angle goniometer at various stages of the sorption/solubility test. Wettability changed over the test period, but not according to theory. The addition type silicones showed little or no sorption and solubility, but two of the condensation type polymers tested had a significant sorption and solubility. This study showed that condensation type polymers may show too large volumetric changes when exposed to fluids, and therefore should no longer be used in prosthetic devices. The results of this study also suggests that it might be of interest to test sorption and solubility of materials that are to be implanted, since most of the materials had some solubility.

  1. 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.

  2. "Mixed-solvency approach" - Boon for solubilization of poorly water-soluble drugs

    Directory of Open Access Journals (Sweden)

    Maheshwari R

    2010-01-01

    Full Text Available Based on a large number of experiments on solubilization of poorly water-soluble drugs, the author is of the opinion that hydrotropy is another type of cosolvency and all water-soluble substances whether liquids, solids, or gases may act as solubilizers for poorly water-soluble drugs. In the present investigation, a mixed-solvency approach has been utilized for solubility enhancement of poorly water-soluble drug, salicylic acid (as a model drug. Sixteen blends (having total 40% w/v strength of solubilizers containing various solubilizers among the commonly used hydrotropes (urea and sodium citrate, cosolvents (glycerin, propylene glycol, PEG 300 and PEG 400, and water-soluble solids (PEG 4000 and PEG 6000 were made to study the influence on solubility of salicylic acid. Twelve blends were found to increase the solubility of salicylic acid, synergistically. This approach shall prove a boon in pharmaceutical field to develop various formulations of poorly water-soluble drugs by combining various water-soluble excipients in safe concentrations to give a strong solution (say 25% w/v or so to produce a desirable aqueous solubility of poorly water-soluble drugs. In the present investigation, the mixed-solvency approach has been employed to analyze salicylic acid in the bulk drug sample (using six blends precluding the use of organic solvents (a way to green chemistry.

  3. 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.

  4. Therapeutic Effects of Water Soluble Danshen Extracts on Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Yoon Hee Cho

    2013-01-01

    Full Text Available Danshen is a traditional Chinese medicine with many beneficial effects on cardiovascular diseases. The aim of this study was to evaluate the mechanisms responsible for the antiatherogenic effect of water soluble Danshen extracts (DEs. Rat vascular smooth muscle cells (VSMCs and human umbilical vein endothelial cells (HUVECs were treated with DE. To evaluate the effects of DE in vivo, carotid balloon injury and tail vein thrombosis were induced in Sprague-Dawley (SD rats and iliac artery stent was induced in New Zealand white rabbits. The inhibitory action of DE on platelet aggregation was confirmed with an impedance aggregometer. DE inhibited the production of reactive oxygen species, and the migration and proliferation of platelet-derived growth factor-BB stimulated VSMCs. Furthermore, DE prevented inflammation and apoptosis in HUVECs. Both effects of DE were reconfirmed in both rat models. DE treatment attenuated platelet aggregation in both in vivo and ex vivo conditions. Pretreatment with DE prevented tail vein thrombosis, which is normally induced by κ-carrageenan injection. Lastly, DE-treated rabbits showed decreased in-stent restenosis of stented iliac arteries. These results suggest that water soluble DE modulates key atherogenic events in VSMCs, endothelial cells, and platelets in both in vitro and in vivo conditions.

  5. Interaction of water-soluble bridged porphyrin with DNA

    Institute of Scientific and Technical Information of China (English)

    Kai WANG; Zhi ZHANG; Qianni GUO; Xiaoping BAO; Zaoying LI

    2008-01-01

    A water-soluble porphyrin dimer (Por Dimer) containing eight positive charges, bridged by 4,4'-dicarboxy-2,2'-bipyridine, has been synthesized. With Meso-tetrakis(N-methyl-pyridium-4-yl)porphyrin (H2TMPyP) as the reference compound, the water-sol-uble porphyrin dimer was investigated for its inter-action with DNA by absorption, fluorescence, and circular dichroism (CD) spectroscopy. The apparent affinity binding constant (Kapp= 1.2×106) of Por Dimer binding to CT DNA was measured by a com-petition method with ethidium bromide (EB) (that of H2TMPyP was 6.9×106). The cleavage ability of Por Dimer to pBR322 plasmid DNA was studied by gel electrophoresis. The results suggest that the binding modes of Por Dimer were complex and involve both intercalation and outside binding.

  6. Drug delivery by water-soluble organometallic cages.

    Science.gov (United States)

    Therrien, Bruno

    2012-01-01

    Until recently, organometallic derivatives were generally viewed as moisture- and air-sensitive compounds, and consequently very challenging to synthesise and very demanding in terms of laboratory requirements (Schlenk techniques, dried solvent, glove box). However, an increasing number of stable, water-soluble organometallic compounds are now available, and organometallic chemistry in aqueous phase is a flourishing area of research. As such, coordination-driven self-assemblies using organometallic building blocks are compatible with water, thus opening new perspectives in bio-organometallic chemistry.This chapter gives a short history of coordination-driven self-assembly, with a special attention to organometallic metalla-cycles, especially those composed of half-sandwich complexes. These metalla-assemblies have been used as sensors, as anticancer agents, as well as drug carriers.

  7. 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

  8. Simultaneous extraction of oil- and water-soluble phase from sunflower seeds with subcritical water.

    Science.gov (United States)

    Ravber, Matej; Knez, Željko; Škerget, Mojca

    2015-01-01

    In this study, the subcritical water extraction is proposed as an alternative and greener processing method for simultaneous removal of oil- and water-soluble phase from sunflower seeds. Extraction kinetics were studied at different temperatures and material/solvent ratios in a batch extractor. Degree of hydrothermal degradation of oils was observed by analysing amount of formed free fatty acids and their antioxidant capacities. Results were compared to oils obtained by conventional methods. Water soluble extracts were analysed for total proteins, carbohydrates and phenolics and some single products of hydrothermal degradation. Highest amount of oil was obtained at 130 °C at a material/solvent ratio of 1/20 g/mL after 30 min of extraction. For all obtained oils minimal degree of hydrothermal degradation could be identified. High antioxidant capacities of oil samples could be observed. Water soluble extracts were degraded at temperatures ≥100 °C, producing various products of hydrothermal degradation.

  9. Highly water-soluble multi-walled carbon nanotubes amine-functionalized by supercritical water oxidation.

    Science.gov (United States)

    Chun, Kyoung-Yong; Moon, In-Kyu; Han, Joo-Hee; Do, Seung-Hoe; Lee, Jin-Seo; Jeon, Seong-Yun

    2013-11-07

    Multi-walled carbon nanotubes (MWNTs) have been amine-functionalized by eco-friendly supercritical water oxidation. The facilely functionalized MWNTs have high solubility (~84 mg L(-1)) in water and 78% transmittance at 30-fold dilution. The Tyndall effect is also shown for several liquids.

  10. A Novel Injectable Water-Soluble Amphotericin B-Arabinogalactan Conjugate

    OpenAIRE

    Falk, Rama; Domb, Abraham J.; Polacheck, Itzhack

    1999-01-01

    New, stable, highly water-soluble, nontoxic polysaccharide conjugates of amphotericin B (AmB) are described. AmB was conjugated by a Schiff-base reaction with oxidized arabinogalactan (AG). AG is a highly branched natural polysaccharide with unusual water solubility (70% in water). A high yield of active AmB was obtained with the conjugates which were similarly highly water soluble and which could be appropriately formulated for injection. They showed comparable MICs for Candida albicans and ...

  11. 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.

  12. Fluorescence characteristics of water soluble organic carbon in eastern China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Fluorescence excitation and average molecular weight of 46 water soluble organic matter (WSOC) samples extracted from 20 soil types in eastern China were determined. It was found all samples shared similar spectroscopy. A good linear relationship existed between total organic carbon and excitation in the range of 350 to 450 nm though the content of organic carbon and pH of the samples vary in a wide range. No significant correlation between relative excitation intensity and average molecular weight of WSOC and FA was found, but the partial correlation became significant with pH as the controlling factor for WSOC samples. The relative excitation intensity showed a general trend of increasing from south to north in the study area. The pH value might play an important role in regulating the fluorescent spatial variation of WSOC.

  13. Biological activities of water-soluble fullerene derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, S; Mashino, T [Department of Pharmaceutical Sciences, Faculty of Pharmacy, Keio University, 1-5-30 Shiba-koen, Minato-ku, Tokyo 105-8512 (Japan)], E-mail: mashino-td@pha.keio.ac.jp

    2009-04-01

    Three types of water-soluble fullerene derivatives were synthesized and their biological activities were investigated. C{sub 60}-dimalonic acid, an anionic fullerene derivative, showed antioxidant activity such as quenching of superoxide and relief from growth inhibition of E. coli by paraquat. C{sub 60}-bis(7V,7V-dimethylpyrrolidinium iodide), a cationic fullerene derivative, has antibacterial activity and antiproliferative effect on cancer cell lines. The mechanism is suggested to be respiratory chain inhibition by reactive oxygen species produced by the cationic fullerene derivative. Proline-type fullerene derivatives showed strong inhibition activities on HIV-reverse transcriptase. The IC{sub 50} values were remarkably lower than nevirapine, a clinically used anti-HIV drug. Fullerene derivatives have a big potential for a new type of lead compound to be used as medicine.

  14. Reactivity of Metal Ions Bound to Water-Soluble Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Sauer, N.N.; Watkins, J.G.; Lin, M.; Birnbaum, E.R.; Robison, T.W.; Smith, B.F.; Gohdes, J.W.; McDonald, J.G.

    1999-06-29

    The intent of this work is to determine the effectiveness of catalysts covalently bound to polymers and to understand the consequences of supporting the catalysts on catalyst efficiency and selectivity. Rhodium phosphine complexes with functional groups for coupling to polymers were prepared. These catalyst precursors were characterized using standard techniques including IR, NMR, and elemental analysis. Studies on the modified catalysts showed that they were still active hydrogenation catalysts. However, tethering of the catalysts to polyamines gave systems with low hydrogenation activity. Analogous biphasic systems were also explored. Phosphine ligands with a surfactant-like structure have been synthesized and used to prepare catalytically active complexes of palladium. The palladium complexes were utilized in Heck-type coupling reactions (e.g. coupling of iodobenzene and ethyl acrylate to produce ethyl cinnamate) under vigorously stirred biphasic reaction conditions, and were found to offer superior performance over a standard water-soluble palladium catalyst under analogous conditions.

  15. ANALYSIS OF SOLUBLE CHEMICAL TRANSFER BY RUNOFF WATER IN FIELD

    Institute of Scientific and Technical Information of China (English)

    TONG Ju-xiu; YANG Jin-zhong

    2008-01-01

    In order to determine the main factors influencing soluble chemical transfer and corresponding techniques for reducing fertilizer loss caused by runoff in irrigated fields, a physically based two-layer model was developed with incomplete mixing theory. Different forms of incomplete mixing parameters were introduced in the model, which was successfully verified with previous published experimental data. According to comparison, the chemicals loss of fertilizer is very sensitive to the runoff-related parameter while it is not sensitive to the infiltration-related parameter. The calculated results show that the chemicals in infiltration water play an important role in the early time of rainfall even with saturated soil, and it is mainly in the runoff flow in the late rainfall. Therefore, prevention of shallow subsurface drainage in the early rainfall is an effective way to reduce fertilizer loss, and the coverage on soil surface is another effective way.

  16. Water Soluble Fluorescent Carbon Nanodots from Biosource for Cells Imaging

    Directory of Open Access Journals (Sweden)

    Kumud Malika Tripathi

    2017-01-01

    Full Text Available Carbon nanodots (CNDs derived from a green precursor, kidney beans, was synthesized with high yield via a facile pyrolysis technique. The CND material was easily modified through simple oxidative treatment with nitric acid, leading to a high density “self-passivated” water soluble form (wsCNDs. The synthesized wsCNDs have been extensively characterized by using various microscopic and spectroscopic techniques and were crystalline in nature. The highly carboxylated wsCNDs possessed tunable-photoluminescence emission behavior throughout the visible region of the spectrum, demonstrating their application for multicolor cellular imaging of HeLa cells. The tunable-photoluminescence properties of “self-passivated” wsCNDs make them a promising candidate as a probe in biological cell-imaging applications.

  17. Drug delivery strategies for poorly water-soluble drugs.

    Science.gov (United States)

    Fahr, Alfred; Liu, Xiangli

    2007-07-01

    The drug candidates coming from combinatorial chemistry research and/or the drugs selected from biologically based high-throughput screening are quite often very lipophilic, as these drug candidates exert their pharmacological action at or in biological membranes or membrane-associated proteins. This challenges drug delivery institutions in industry or academia to develop carrier systems for the optimal oral and parenteral administration of these drugs. To mention only a few of the challenges for this class of drugs: their oral bioavailability is poor and highly variable, and carrier development for parenteral administration is faced with problems, including the massive use of surface-active excipients for solubilisation. Formulation specialists are confronted with an even higher level of difficulties when these drugs have to be delivered site specifically. This article addresses the emerging formulation designs for delivering of poorly water-soluble drugs.

  18. Antioxidant Properties of Water-Soluble Gum from Flaxseed Hulls.

    Science.gov (United States)

    Bouaziz, Fatma; Koubaa, Mohamed; Barba, Francisco J; Roohinejad, Shahin; Chaabouni, Semia Ellouz

    2016-08-02

    Soluble flaxseed gum (SFG) was extracted from flax (Linum usitatissimum) hulls using hot water, and its functional groups and antioxidant properties were investigated using infrared spectroscopy and different antioxidant assays (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), reducing power capacity, and β-carotene bleaching inhibition assay), respectively. The antioxidant capacity of SFG showed interesting DPPH radical-scavenging capacity (IC50 SFG = 2.5 mg·mL(-1)), strong ABTS radical scavenging activity (% inhibition ABTS = 75.6% ± 2.6% at 40 mg·mL(-1)), high reducing power capacity (RPSFG = 5 mg·mL(-1)), and potent β-carotene bleaching inhibition activity (IC50 SFG = 10 mg·mL(-1)). All of the obtained results demonstrate the promising potential use of SFG in numerous industrial applications, and a way to valorize flaxseed hulls.

  19. Water Solubility in the Proto-Lunar Disk

    Science.gov (United States)

    Hauri, E. H.; Nakajima, M.

    2016-12-01

    The giant impact model is the scenario most widely accepted for the origin of the Moon, yet no satisfactory version of this model exists to explain the Earth-like H2O content of primitive lunar magmas. Here we investigate the likelihood that H2O from the Earth was transferred to the Moon in the aftermath of the giant impact. Nearly all variants of the giant impact model produce an energetic impact-generated debris disk that eventually coalesces to form the Moon [1]. Here we investigate the behavior of H2O in disks of Bulk Silicate Earth (BSE) composition produced by three impact scenarios; (a) the standard model of a Mars-sized impactor striking the proto-Earth [2]; (b) impact into a fast-spinning Earth [3]; and (c) impact of two sub-earths each being half the mass of the current Earth [4]. All of these models have been shown to be sufficiently energetic that, at maximum entropy and hydrostatic equilibrium following the impact, most of the mass of the proto-lunar disk consists of silicate melt and vapor, with vapor mass fractions ranging from 20-100% and mid-plane temperatures of 3500-6000K [1]. From these models, we calculate the 2D axisymmetric pressure structure of the disk, and calculate the solubility of H2O in liquid droplets that condense from the vapor atmosphere. Assuming a high bulk Earth H2O content of 1000 ppm, at the Roche radius and close to the disk midplane where pressures are highest (1 to 1000 bars), the mass fraction of all H-bearing species in the vapor is calculated to be ≤0.001, and the maximum H2O solubility in silicate melt is predicted to be ppm because most of the water is dissociated at these high temperatures, in agreement with [5]. As the disk cools past the condensation of silicate vapor, the remaining vapor is dominated by Na and similarly volatile elements, with H2O a minor component of the vapor phase from 2500-1000K. The calculated vapor pressures are low at the midplane with strong vertical gradients, and thus calculated H2O

  20. Fat-soluble and water-soluble vitamin contents of breast milk from Japanese women.

    Science.gov (United States)

    Sakurai, Takayuki; Furukawa, Miyako; Asoh, Miyuki; Kanno, Takahiro; Kojima, Tadashi; Yonekubo, Akie

    2005-08-01

    To determine the concentrations of fat-soluble and water-soluble vitamins in the maternal milk of Japanese women, we collected human milk samples from more than 4,000 mothers living throughout Japan between December 1998 and September 1999, and defined as group A the 691 samples among these that met the following conditions: breast milk of mothers who were under 40 y of age, who did not smoke habitually and/or use vitamin supplements, and whose babies showed no symptoms of atopy and had birth weights of 2.5 kg or more. We then analyzed the contents of vitamins individually. Large differences were observed among the contents of individual human milk samples. The mean contents of each component were as follows: vitamin A, 159.0 +/- 95.2 IU/100 mL; vitamin E, 0.325 +/- 0.165 alpha-TE mg/100mL; vitamin D3 (cholecalciferol), 8.0 +/- 10.7 ng/100mL; vitamin B1 (thiamin), 12.3 +/- 3.2 microg/100 mL; vitamin B2, 38.4 +/- 12.7 microg/100 mL; vitamin B6, 5.7 +/- 2.5 microg/100 mL; vitamin B12, 0.04 +/- 0.02 microg/100 mL; vitamin C, 5.1 +/- 1.9 mg/100 mL; biotin, 0.50 +/- 0.23 microg/100 mL; choline, 9.2 +/- 1.8 mg/100 mL; folic acid, 6.2 +/- 2.9 microg/100 mL; inositol, 12.6 +/- 3.6 mg/100 mL; niacin (nicotinamide), 32.9 +/- 20.4 microg/100 mL and pantothenic acid, 0.27 +/- 0.09 mg/100 mL. The concentrations of derivatives and/or related compounds of vitamin A (retinol, beta-carotene), vitamin E (alpha-, beta-, gamma-, and delta-tocopherol), and B2 (riboflavin, FMN, and FAD) were determined separately. The contents of each were found to vary greatly as the duration of lactation increased. The present results indicate that it is necessary to evaluate individual differences in human milk in order to perform valid research regarding infant formula.

  1. Water-soluble polymers for recovery of metal ions from aqueous streams

    Science.gov (United States)

    Smith, Barbara F.; Robison, Thomas W.

    1998-01-01

    A process of selectively separating a target metal contained in an aqueous solution by contacting the aqueous solution containing a target metal with an aqueous solution including a water-soluble polymer capable of binding with the target metal for sufficient time whereby a water-soluble polymer-target metal complex is formed, and, separating the solution including the water-soluble polymer-target metal complex from the solution is disclosed.

  2. Morphological Analysis and Solubility of Lead Particles: Effect of Phosphates and Implications to Drinking Water Distribution

    Science.gov (United States)

    Objective • Describe lead synthesis experiments conduced to model the impact of water quality on lead particles and solubility • Develop a model system that can be used for lead solubility studies • Understand the how phosphates impact the morphology and solubility transfo...

  3. 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.

  4. Water-soluble ruthenium complexes bearing activity against protozoan parasites.

    Science.gov (United States)

    Sarniguet, Cynthia; Toloza, Jeannette; Cipriani, Micaella; Lapier, Michel; Vieites, Marisol; Toledano-Magaña, Yanis; García-Ramos, Juan Carlos; Ruiz-Azuara, Lena; Moreno, Virtudes; Maya, Juan Diego; Azar, Claudio Olea; Gambino, Dinorah; Otero, Lucía

    2014-06-01

    Parasitic illnesses are major causes of human disease and misery worldwide. Among them, both amebiasis and Chagas disease, caused by the protozoan parasites, Entamoeba histolytica and Trypanosoma cruzi, are responsible for thousands of annual deaths. The lack of safe and effective chemotherapy and/or the appearance of current drug resistance make the development of novel pharmacological tools for their treatment relevant. In this sense, within the framework of the medicinal inorganic chemistry, metal-based drugs appear to be a good alternative to find a pharmacological answer to parasitic diseases. In this work, novel ruthenium complexes [RuCl2(HL)(HPTA)2]Cl2 with HL=bioactive 5-nitrofuryl containing thiosemicarbazones and PTA=1,3,5-triaza-7-phosphaadamantane have been synthesized and fully characterized. PTA was included as co-ligand in order to modulate complexes aqueous solubility. In fact, obtained complexes were water soluble. Their activity against T. cruzi and E. histolytica was evaluated in vitro. [RuCl2(HL4)(HPTA)2]Cl2 complex, with HL4=N-phenyl-5-nitrofuryl-thiosemicarbazone, was the most active compound against both parasites. In particular, it showed an excellent activity against E. histolytica (half maximal inhibitory concentration (IC50)=5.2 μM), even higher than that of the reference drug metronidazole. In addition, this complex turns out to be selective for E. histolytica (selectivity index (SI)>38). The potential mechanism of antiparasitic action of the obtained ruthenium complexes could involve oxidative stress for both parasites. Additionally, complexes could interact with DNA as second potential target by an intercalative-like mode. Obtained results could be considered a contribution in the search for metal compounds that could be active against multiple parasites.

  5. Solubility of sodium chloride in superionic water ice

    Science.gov (United States)

    Hernandez, Jean-Alexis; Caracas, Razvan

    2017-04-01

    In icy planets, complex interactions are expected to occur at the interface between the rocky core and the icy mantle composed of mixtures based on water, methane, and ammonia [1, 2]. The hydration of the silicate layer produces salts (MgSO4, NaCl, KCl) that could mix with the ice, and change considerably its properties [3]. Here, we used first-principles molecular dynamics to investigate the stability and the properties of the binary system NaCl-H2O at the relevant thermodynamic conditions for planetary interiors up to ice giants. In these conditions, pure water ice undergoes several transitions that affect considerably its ionic conductivity and its elastic properties [4]. We calculated the Gibbs free energy of mixing along the NaCl-H2O binary by applying Boltzmann statistics to account for energy differences between configurations. We evaluated vibrational entropy from the vibrational spectra of the nuclei motion using the recently developed two phases thermodynamic memory function (2PT-MF) model for multicomponent systems [5, 6]. We show that the solubility of NaCl in water ice at 1600 K is less than 0.78 mol%. We find that salty ices present an extended superionic domain toward high pressures in comparison to pure water ice. Finally, we predict that the complete symmetrization of the hydrogen bonds (i.e. transition to ice X) occurs at higher pressure than in pure water ice, as observed in LiCl doped water ice at ambient temperature [7]. References: [1] M. R. Frank, C. E. Runge, H. P. Scott, S. J. Maglio, J. Olson, V. B. Prakapenka, G. Shen, PEPI 155 (2006) 152-162 [2] B. Journaux, I. Daniel, R. Caracas, G. Montagnac, H. Cardon, Icarus 226 (2013) 355-363 [3] S. Klotz, L. E. Bove, T. Strässle, T. C. Hansen, A. M. Saitta, Nature Materials 8 (2009) 405-409 [4] J. -A. Hernandez, R. Caracas, Phys. Rev. Lett. 117 (2016) 135503 [5] M. P. Desjarlais, Phys. Rev. E 88 (2013) 062145 [6] M. French, M. P. Desjarlais, R. Redmer, Phys. Rev. E 93 (2016) 022140 [7] L. E. Bove

  6. Simultaneous Rapid Determination of the Solubility and Diffusion Coefficients of a Poorly Water-Soluble Drug Based on a Novel UV Imaging System.

    Science.gov (United States)

    Lu, Yan; Li, Mingzhong

    2016-01-01

    The solubility and diffusion coefficient are two of the most important physicochemical properties of a drug compound. In practice, both have been measured separately, which is time consuming. This work utilizes a novel technique of UV imaging to determine the solubility and diffusion coefficients of poorly water-soluble drugs simultaneously. A 2-step optimal method is proposed to determine the solubility and diffusion coefficients of a poorly water-soluble pharmaceutical substance based on the Fick's second law of diffusion and UV imaging measurements. Experimental results demonstrate that the proposed method can be used to determine the solubility and diffusion coefficients of a drug with reasonable accuracy, indicating that UV imaging may provide a new opportunity to accurately measure the solubility and diffusion coefficients of a poorly water-soluble drug simultaneously and rapidly. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  7. EPR and Structural Characterization of Water-Soluble Mn(2+)-Doped Si Nanoparticles.

    Science.gov (United States)

    Atkins, Tonya M; Walton, Jeffrey H; Singh, Mani P; Ganguly, Shreyashi; Janka, Oliver; Louie, Angelique Y; Kauzlarich, Susan M

    2017-01-26

    Water-soluble poly(allylamine) Mn(2+)-doped Si (SiMn) nanoparticles (NPs) were prepared and show promise for biologically related applications. The nanoparticles show both strong photoluminescence and good magnetic resonance contrast imaging. The morphology and average diameter were obtained through transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM); spherical crystalline Si NPs with an average diameter of 4.2 ± 0.7 nm were observed. The doping maximum obtained through this process was an average concentration of 0.4 ± 0.3% Mn per mole of Si. The water-soluble SiMn NPs showed a strong photoluminescence with a quantum yield up to 13%. The SiMn NPs had significant T1 contrast with an r1 relaxivity of 11.1 ± 1.5 mM(-1) s(-1) and r2 relaxivity of 32.7 ± 4.7 mM(-1) s(-1) where the concentration is in mM of Mn(2+). Dextran-coated poly(allylamine) SiMn NPs produced NPs with T1 and T2 contrast with a r1 relaxivity of 27.1 ± 2.8 mM(-1) s(-1) and r2 relaxivity of 1078.5 ± 1.9 mM(-1) s(-1). X-band electron paramagnetic resonance spectra are fit with a two-site model demonstrating that there are two types of Mn(2+) in these NP's. The fits yield hyperfine splittings (A) of 265 and 238 MHz with significant zero field splitting (D and E terms). This is consistent with Mn in sites of symmetry lower than tetrahedral due to the small size of the NP's.

  8. [Study of water-soluble compounds from fungus garden of Odontotermes formosanus].

    Science.gov (United States)

    Xue, Dejun; Zhou, Hui; Zhang, Min; Xie, Kang; Zhang, Yong

    2005-10-01

    To study water-soluble compounds from fungus garden of Odontotermes formosanus. The chemical constituents of fungus garden were analyzed and identified by GC-MS. 28 compounds were separated and 11 chemical constituents were identified. The main constituents in water-solubles from fungus garden of Odontotermes formosanus are palmitic acid, linolei acid and oleic aid.

  9. Extended Hildebrand solubility approach: Satranidazole in mixtures of dioxane and water

    Directory of Open Access Journals (Sweden)

    P B Rathi

    2011-01-01

    Full Text Available The extended Hildebrand solubility parameter approach is used to estimate the solubility of satranidazole in binary solvent systems. The solubility of satranidazole in various dioxane-water mixtures was analyzed in terms of solute-solvent interactions using a modified version of Hildebrand-Scatchard treatment for regular solutions. The solubility of satranidazole in the binary solvent, dioxane-water shows a bell-shaped profile with a solubility maximum well above the ideal solubility of the drug. This is attributed to solvation of the drug with the dioxane-water mixture, and indicates that the solute-solvent interaction energy is larger than the geometric mean (δ1δ2 of regular solution theory. The new approach provides an accurate prediction of solubility once the interaction energy is obtained. In this case, the energy term is regressed against a polynomial in δ1 of the binary mixture. A quartic expression of W in terms of solvent solubility parameter was found for predicting the solubility of satranidazole in dioxane-water mixtures. The method has potential usefulness in preformulation and formulation studies during which solubility prediction is important for drug design.

  10. Extended hildebrand solubility approach: satranidazole in mixtures of dioxane and water.

    Science.gov (United States)

    Rathi, P B; Mourya, V K

    2011-05-01

    The extended Hildebrand solubility parameter approach is used to estimate the solubility of satranidazole in binary solvent systems. The solubility of satranidazole in various dioxane-water mixtures was analyzed in terms of solute-solvent interactions using a modified version of Hildebrand-Scatchard treatment for regular solutions. The solubility of satranidazole in the binary solvent, dioxane-water shows a bell-shaped profile with a solubility maximum well above the ideal solubility of the drug. This is attributed to solvation of the drug with the dioxane-water mixture, and indicates that the solute-solvent interaction energy is larger than the geometric mean (δ(1)δ(2)) of regular solution theory. The new approach provides an accurate prediction of solubility once the interaction energy is obtained. In this case, the energy term is regressed against a polynomial in δ(1) of the binary mixture. A quartic expression of W in terms of solvent solubility parameter was found for predicting the solubility of satranidazole in dioxane-water mixtures. The method has potential usefulness in preformulation and formulation studies during which solubility prediction is important for drug design.

  11. Water-soluble primary amine compounds in rural continental precipitation

    Science.gov (United States)

    Gorzelska, Krystyna; Galloway, James N.; Watterson, Karen; Keene, William C.

    Procedures for collecting, storing and analysing precipitation samples for organic nitrogen studies were developed. These procedures preserve chemical integrities of the species of interest, allow for up to 3 months storage and quantitative determination of water-soluble primary amine compounds, with the overall error at the 2 nM detection limit of less than 30%. This methodology was applied to study amino compounds in precipitation samples collected over a period of one year in central Virginia. Nitrogen concentrations of 13 amino acids and 3 aliphatic amines were summed to calculate the total amine nitrogen (TAN). The concentration of TAN ranged from below our detection level to 6658 nM, and possibly reflected a seasonal variation in the source strength of the atmospheric amines. Overall, the most commonly occurring amino compounds were methyl amine, ethyl amine, glutamic acid, glycine and serine. On average, the highest overall contribution to the TAN came from arginine, asparagine, glutamine, methyl amine, serine and alanine. However, large qualitative and quantitative variations observed among samples warrant caution in interpretation and application of the averaged values. TAN in Charlottesville precipitation contributed from less than 1 to ca 10% of the ammonium nitrogen level. However, our estimates show that amino compounds may contribute significantly to reduced nitrogen budget in precipitation in remote regions.

  12. 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.

  13. Image Charge Effects in the Wetting Behavior of Alkanes on Water with Accounting for Water Solubility

    Directory of Open Access Journals (Sweden)

    Kirill A. Emelyanenko

    2016-03-01

    Full Text Available Different types of surface forces, acting in the films of pentane, hexane, and heptane on water are discussed. It is shown that an important contribution to the surface forces originates from the solubility of water in alkanes. The equations for the distribution of electric potential inside the film are derived within the Debye-Hückel approximation, taking into account the polarization of the film boundaries by discrete charges at water-alkane interface and by the dipoles of water molecules dissolved in the film. On the basis of above equations we estimate the image charge contribution to the surface forces, excess free energy, isotherms of water adsorption in alkane film, and the total isotherms of disjoining pressure in alkane film. The results indicate the essential influence of water/alkane interface charging on the disjoining pressure in alkane films, and the wettability of water surface by different alkanes is discussed.

  14. Linking Atomistic and Mesoscale Simulations of Water Soluble Polymers

    Science.gov (United States)

    Jones, J. L.

    2003-03-01

    There exist a range of techniques for studying surfactants and polymers in the mesoscale regime. One of the challenges is to link mesoscale theories and simulations to other calculation methods which address different length scales of the system. We introduce some mesoscale methods of calculation for polymers and surfactants and then present a case study of where mesoscale modelling is used for mechanistic understanding, by linking the method to high throughput in-silico screening methods. We look at the adsorption onto silica of ethylene oxide (EO)/ propylene oxide (PO) block copolymers (lutrols) which have been modified by end-grafting of short, cationic dimethylamino ethyl methacrylate (DMAEMA)chains. Given that the silica surface is negatively charged, it is remarkable that in some circumstances, polymers with longercationic chains have a lower adsorption. The effect is attributed to a competition between strong adsorption of the cationic DMAEMA groups driven by electrostatics, and weaker adsorption of the more numerous EO groups. This then raises the question of how we produce the values for the mesoscale parameters in these models and in the second part of the talk we describe a calculation method for doing this for water soluble polymers. The most promising route, but notoriously costly, is based on free energy calculations at the atomistic level. Free energy calculations are computationally intensive in general, but in an aqueous system one is also faced with the additional problem of using complex continuum models and/or accurate interaction potentials for water. Here we show how potential of mean force (PMF)calculations offer a practical alternative which avoids these drawbacks, though one is still faced with extremely long simulations.

  15. Determination and Prediction of Binary Solubility for Aromatic-Tetraethylene Glycol (with Water) Systems

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The binary solubilities of tetraethylene glycol (TTEG) with benzene, toluene or p-xylene, were measured by the turbidity point method. In TTEG the content of water ranged from 0 to 5% and the test temperature ranged from 20℃ to 120℃. Increasing the temperature resulted in greater solubility of the aromatics in TTEG, while increasing the content of water caused the aromatic solubility to decrease. The benzene solubillity in TTEG was the greatest followed by toluene and xylene at the same water content and temperature. The mutual solubility was predicted by correlating the paramaters of a new group for the UNIFAC model for the aromatics extraction system. The modified UNIFAC group contribution model was used to predict the binary solubility of TTEG and aromatics. The average deviation between the experimental result and prediction is 4.06%. Therefore, the UNIFAC model can be used to describe the solubility phenomena for TTEG-aromatics systems.

  16. Water-Soluble 2-Hydroxyisophthalamides for Sensitization of Lanthanide Luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Samuel, Amanda P. S.; Moore, Evan G.; Melchior, Marco; Xu, Jide; Raymond, Kenneth N.

    2008-02-20

    A series of octadentate ligands featuring the 2-hydroxyisophthalamide (IAM) antenna chromophore (to sensitize Tb(III) and Eu(III) luminescence) has been prepared and characterized. The length of the alkyl amine scaffold that links the four IAM moieties has been varied in order to investigate the effect of the ligand backbone on the stability and photophysical properties of the Ln(III) complexes. The amine backbones utilized in this study are N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-ethane-1,2-diamine [H(2,2)-], N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-propane-1,3-diamine [H(3,2)-] and N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-butane-1,4-diamine [H(4,2)-]. These ligands also incorporate methoxyethylene [MOE] groups on each of the IAM chromophores to increase their water solubility. The aqueous ligand protonation constants and Tb(III) and Eu(III) formation constants were determined from solution thermodynamic studies. The resulting values indicate that at physiological pH, the Eu(III) and Tb(III) complexes of H(2,2)-IAM-MOE and H(4,2)-IAM-MOE are sufficiently stable to prevent dissociation at nanomolar concentrations. The photophysical measurements for the Tb(III) complexes gave overall quantum yield values of 0.56, 0.39, and 0.52 respectively for the complexes with H(2,2)-IAM-MOE, H(3,2)-IAM-MOE and H(4,2)-IAM-MOE, while the corresponding Eu(III) complexes displayed significantly weaker luminescence, with quantum yield values of 0.0014, 0.0015, and 0.0058, respectively. Analysis of the steady state Eu(III) emission spectra provides insight into the solution symmetries of the complexes. The combined solubility, stability and photophysical performance of the Tb(III) complexes in particular make them well suited to serve as the luminescent reporter group in high sensitivity time-resolved fluoroimmunoassays.

  17. Water-Soluble 2-Hydroxyisophthalamides for Sensitization of Lanthanide Luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Samuel, Amanda P. S.; Moore, Evan G.; Melchior, Marco; Xu, Jide; Raymond, Kenneth N.

    2008-02-20

    A series of octadentate ligands featuring the 2-hydroxyisophthalamide (IAM) antenna chromophore (to sensitize Tb(III) and Eu(III) luminescence) has been prepared and characterized. The length of the alkyl amine scaffold that links the four IAM moieties has been varied in order to investigate the effect of the ligand backbone on the stability and photophysical properties of the Ln(III) complexes. The amine backbones utilized in this study are N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-ethane-1,2-diamine [H(2,2)-], N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-propane-1,3-diamine [H(3,2)-] and N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-butane-1,4-diamine [H(4,2)-]. These ligands also incorporate methoxyethylene [MOE] groups on each of the IAM chromophores to increase their water solubility. The aqueous ligand protonation constants and Tb(III) and Eu(III) formation constants were determined from solution thermodynamic studies. The resulting values indicate that at physiological pH, the Eu(III) and Tb(III) complexes of H(2,2)-IAM-MOE and H(4,2)-IAM-MOE are sufficiently stable to prevent dissociation at nanomolar concentrations. The photophysical measurements for the Tb(III) complexes gave overall quantum yield values of 0.56, 0.39, and 0.52 respectively for the complexes with H(2,2)-IAM-MOE, H(3,2)-IAM-MOE and H(4,2)-IAM-MOE, while the corresponding Eu(III) complexes displayed significantly weaker luminescence, with quantum yield values of 0.0014, 0.0015, and 0.0058, respectively. Analysis of the steady state Eu(III) emission spectra provides insight into the solution symmetries of the complexes. The combined solubility, stability and photophysical performance of the Tb(III) complexes in particular make them well suited to serve as the luminescent reporter group in high sensitivity time-resolved fluoroimmunoassays.

  18. Overview of milling techniques for improving the solubility of poorly water-soluble drugs

    Directory of Open Access Journals (Sweden)

    Zhi Hui Loh

    2015-07-01

    Full Text Available Milling involves the application of mechanical energy to physically break down coarse particles to finer ones and is regarded as a “top–down” approach in the production of fine particles. Fine drug particulates are especially desired in formulations designed for parenteral, respiratory and transdermal use. Most drugs after crystallization may have to be comminuted and this physical transformation is required to various extents, often to enhance processability or solubility especially for drugs with limited aqueous solubility. The mechanisms by which milling enhances drug dissolution and solubility include alterations in the size, specific surface area and shape of the drug particles as well as milling-induced amorphization and/or structural disordering of the drug crystal (mechanochemical activation. Technology advancements in milling now enable the production of drug micro- and nano-particles on a commercial scale with relative ease. This review will provide a background on milling followed by the introduction of common milling techniques employed for the micronization and nanonization of drugs. Salient information contained in the cited examples are further extracted and summarized for ease of reference by researchers keen on employing these techniques for drug solubility and bioavailability enhancement.

  19. Analysis of Hysterosalpingography in 1369 Infertility Patients with Water Soluble Contrast Medium under Digital Subtraction Angiography%1369例不孕患者水溶性造影剂DSA下动态子宫输卵管造影分析

    Institute of Scientific and Technical Information of China (English)

    田芳玲; 陈硕飞; 王海峰; 曲尔青; 郭晓丽; 田锦林

    2014-01-01

    目的:探讨原发性不孕(PI)与继发性不孕(SI)患者子宫输卵管造影(HSG)的特点及导致输卵管不通畅的危险因素。方法回顾性分析1369例不孕患者的水溶性造影剂DSA下HSG造影资料,根据不孕的原因为PI及SI两组,对两组一般情况及造影结果进行比较;再以双侧输卵管通畅与否为因变量,以年龄、生育史、是否有宫外孕史、盆腔手术史、输卵管结核病史、流产史、原发或继发性不孕、合并其它疾病与否、子宫形态异常与否为自变量,进行多因素二分类logistic回归分析,探讨输卵管不通畅的危险因素。结果 PI组年龄比SI组小[(27.27±3.82)岁vs(29.97±4.80)岁],双侧输卵管通畅率较SI组高(45.50%vs 34.74%),两组比较有统计学差异(P<0.05);Logistic回归分析显示年龄、宫外孕史、流产史及子宫形态异常是输卵不通畅的危险因素(OR值=0.903、0.198、1.542、0.120;95%的可信区间:0.903~0.958、0.120~0.352、1.002~2.375、0.036~0.399)。结论 PI和SI在年龄及输卵管通畅率方面存在差异,大龄、宫外孕史、流产史及子宫形态异常是输卵不通畅的危险因素。%Objective To analysis the hysterosalpingography(HSG) features of primary infertile(PI) and secondary infertile(SI) patients and related risk factors of Fallopian tubal blockage and incomplete patency. Methods Digital subtraction angiography(DSA) imaging data of HSG with water soluble contrast medium in 1369 infertile patients were retrospectively analyzed. Patients were divided into two groups according to etiopathogenisis of infertility, including PI group and SI group. The general states and appearance of HSG were compared between the two groups. And then, with bilateral tubal patency or not as a dependent, and with age,childbearing history or not, ectopic pregnancy(EP) history or not, pelvic surgery history or not, tubal tuberculosis history or not

  20. Effect of Cold Water Immersion or Contrast Water Therapy on Muscle Soreness After Exercise

    National Research Council Canada - National Science Library

    C A Lauber; S Hickle; J Jargstorf; W West

    2017-01-01

    An abstract of a study by Lauber et al determining if post-exercise cold-water immersion decreases muscle soreness compared to contrast water therapy at 48 hours post delayed onset muscle soreness (DOMS...

  1. Determination and evaluation of solubility parameter of satranidazole using dioxane-water system

    Directory of Open Access Journals (Sweden)

    Rathi P

    2010-01-01

    Full Text Available Satranidazole, a potent broad spectrum antiprotozoal, is a poorly water-soluble drug and has low bioavailability on oral administration. One of the important methods to improve the solubility and bioavailability of a less water-soluble drug is by the use of cosolvents. The solubility enhancement produced by binary blends with a cosolvent (dioxane was studied against the solubility parameter of solvent blends (d1 to evaluate the solubility parameter of drug (d2 . Solubility parameter of drug (d2 was evaluated in blends of dioxane-water system. The results obtained were compared with the d2 values obtained using Molar Volume Method and Fedor′s Group Substitution Method. The binary blend water-dioxane (10:90 gave maximum solubility with an experimental d2 value of 11.34 (Cal/cm 3 0.5 that was comparable to the theoretical values of 11.34 (Cal/cm 3 0.5 determined by Molar Volume Method and 11.3928 (Cal/cm 3 0.5 when determined by Fedor′s Group Substitution Method, which is in good agreement with solubility measurement method.

  2. 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.

  3. CONTRAST

    DEFF Research Database (Denmark)

    Kristensen, Thomas Krogsgaard

    2007-01-01

    Dette er en afrapportering fra den årlige CONTRAST workshop, der i 2007 blev afholdt i Yaoundé, Cameroon.......Dette er en afrapportering fra den årlige CONTRAST workshop, der i 2007 blev afholdt i Yaoundé, Cameroon....

  4. Water-enhanced solubility of carboxylic acids in organic solvents and its applications to extraction processes

    Energy Technology Data Exchange (ETDEWEB)

    Starr, J.N.; King, C.J.

    1991-11-01

    The solubilities of carboxylic acids in certain organic solvents increase remarkably with an increasing amount of water in the organic phase. This phenomenon leads to a novel extract regeneration process in which the co-extracted water is selectively removed from an extract, and the carboxylic acid precipitates. This approach is potentially advantageous compared to other regeneration processes because it removes a minor component of the extract in order to achieve a large recovery of acid from the extract. Carboxylic acids of interest include adipic acid, fumaric acid, and succinic acid because of their low to moderate solubilities in organic solvents. Solvents were screened for an increase in acid solubility with increased water concentration in the organic phase. Most Lewis-base solvents were found to exhibit this increased solubility phenomena. Solvents that have a carbonyl functional group showed a very large increase in acid solubility. 71 refs., 52 figs., 38 tabs.

  5. Assessing water quality trends in catchments with contrasting hydrological regimes

    Science.gov (United States)

    Sherriff, Sophie C.; Shore, Mairead; Mellander, Per-Erik

    2016-04-01

    Environmental resources are under increasing pressure to simultaneously achieve social, economic and ecological aims. Increasing demand for food production, for example, has expanded and intensified agricultural systems globally. In turn, greater risks of diffuse pollutant delivery (suspended sediment (SS) and Phosphorus (P)) from land to water due to higher stocking densities, fertilisation rates and soil erodibility has been attributed to deterioration of chemical and ecological quality of aquatic ecosystems. Development of sustainable and resilient management strategies for agro-ecosystems must detect and consider the impact of land use disturbance on water quality over time. However, assessment of multiple monitoring sites over a region is challenged by hydro-climatic fluctuations and the propagation of events through catchments with contrasting hydrological regimes. Simple water quality metrics, for example, flow-weighted pollutant exports have potential to normalise the impact of catchment hydrology and better identify water quality fluctuations due to land use and short-term climate fluctuations. This paper assesses the utility of flow-weighted water quality metrics to evaluate periods and causes of critical pollutant transfer. Sub-hourly water quality (SS and P) and discharge data were collected from hydrometric monitoring stations at the outlets of five small (~10 km2) agricultural catchments in Ireland. Catchments possess contrasting land uses (predominantly grassland or arable) and soil drainage (poorly, moderately or well drained) characteristics. Flow-weighted water quality metrics were calculated and evaluated according to fluctuations in source pressure and rainfall. Flow-weighted water quality metrics successfully identified fluctuations in pollutant export which could be attributed to land use changes through the agricultural calendar, i.e., groundcover fluctuations. In particular, catchments with predominantly poor or moderate soil drainage

  6. Preparation of water-soluble nanographite and its application in water-based cutting fluid

    Science.gov (United States)

    Chen, Qiang; Wang, Xue; Wang, Zongting; Liu, Yu; You, Tingzheng

    2013-01-01

    Water-soluble nanographite was prepared by in situ emulsion polymerization using methacrylate as polymeric monomer. The dispersion stability and dispersion state of graphite particles were evaluated by UV-visible spectrophotometry and scanning electron microscopy, respectively. The water-soluble nanographite was then added into the water-based cutting fluid as lubricant additive. The lubrication performance of water-based cutting fluid with the nanographite additive was studied on four-ball friction tester and surface tensiometer. Results indicate that the modification method of in situ emulsion polymerization realizes the uniform and stabilized dispersion of nanographite in aqueous environment. The optimal polymerization condition is 70°C (polymerization temperature) and 5 h (polymerization time). The addition of nanographite decreases the friction coefficient and wear scar diameter by 44% and 49%. Meanwhile, the maximum non-seizure load ( P B ) increases from 784 to 883 N, and the value of surface tension (32.76 × 10-3 N/m) is at low level. Nanographite additive improves apparently the lubrication performance of water-based cutting fluid.

  7. 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)

  8. Water-Soluble Multi-Walled Nanotube and its Film Characteristics

    Institute of Scientific and Technical Information of China (English)

    FENG Wei(郭镇); ZHOU Feng(红); WANG Xiao-Gong(叶瑜黄); WAN Mei-Xiang(星景志); FUJII Akihiko(圣锦); YOSHINO Katsumi(江冰林)

    2003-01-01

    Covalent modification of multi-walled-nanotube (MWNT) surface-enhanced solubility in water yields a thin transparent shining dark-coloured film of soluble MWNT (s-MWNT) with a conductivity of 1.25S/cm. Fourier transform infrared spectroscopy, scanning electron microscopy, transmission-electron microscopy, and UV-vis absorption spectroscopy were used for thefilm characterization. The result shows that enhanced interactions between s-MWNT and water and between s-MWNTs play an important role in increasing the solubility of the nanotubes in water and in the formation of uniform thin films.

  9. Explaining Ionic Liquid Water Solubility in Terms of Cation and Anion Hydrophobicity

    Directory of Open Access Journals (Sweden)

    Johannes Ranke

    2009-03-01

    Full Text Available The water solubility of salts is ordinarily dictated by lattice energy and ion solvation. However, in the case of low melting salts also known as ionic liquids, lattice energy is immaterial and differences in hydrophobicity largely account for differences in their water solubility. In this contribution, the activity coefficients of ionic liquids in water are split into cation and anion contributions by regression against cation hydrophobicity parameters that are experimentally determined by reversed phase liquid chromatography. In this way, anion hydrophobicity parameters are derived, as well as an equation to estimate water solubilities for cation-anion combinations for which the water solubility has not been measured. Thus, a new pathway to the quantification of aqueous ion solvation is shown, making use of the relative weakness of interactions between ionic liquid ions as compared to their hydrophobicities.

  10. Determination of Water Content of Water-soluble Paints by Gas Chromatography

    Institute of Scientific and Technical Information of China (English)

    顾润南; 钦维民; 肖舸

    2003-01-01

    This paper describes the determination of water content of water-soluble paints by gas chromatography. The water in paints is extracted by dimethyl formamide (DMF) as a solvent.Isopropanol is used as an internal standard. The mixture is separated by low-speed centrifugation.Then a 1-uL sample of the supernatant from the prepared solution is injected into the gas chromatograph. The water content is determined by internal standard calibration curve. The rate of recovery of added standard of this method is more than 98%. Relative mean deviation is less than 3‰.The linearity of calibration curve is good and relativity coefficient is higher than 0.998.

  11. One-year water sorption and solubility of "all-in-one" adhesives.

    Science.gov (United States)

    Walter, Ricardo; Feiring, Andrew E; Boushell, Lee W; Braswell, Krista; Bartholomew, Whitley; Chung, Yunro; Phillips, Ceib; Pereira, Patricia N R; Swift, Edward J

    2013-01-01

    The aim of this study was to evaluate the water sorption and solubility of different adhesives. Adper Easy Bond, Adper Single Bond Plus, Bond Force, Clearfil SE Bond (bonding resin only), and Xeno IV were the materials evaluated. Ten disks of each adhesive were made in Teflon molds and evaporation of any volatile components was allowed. The disks were weighed daily in an analytical balance until a constant mass was obtained (m1). Disks were then immersed in water for 12 months when their wet weight was recorded (m2). The disks were again weighed daily until a constant mass was obtained and the final weight recorded (m3). Water sorption and solubility (percentages) were calculated using the recorded mass values. Kruskal-Wallis tests were used to compare the average water sorption and solubility among the different adhesives. Mann-Whitney tests with a Bonferroni correction were used to determine the pairwise differences between adhesives in water sorption and solubility. The level of significance was set at 0.05. Water sorption and solubility were significantly different among the groups (p0.05) between Adper Single Bond Plus and Bond Force, or between Clearfil SE Bond and Xeno IV in either water sorption or solubility. Xeno IV did not differ from Adper Easy Bond in water sorption (p>0.05). Water sorption and solubility of all-in-one adhesives increased with time, and the rates of increase were composition-dependent. The results suggest that monomers other than HEMA contribute to water sorption and solubility of adhesive systems from different categories.

  12. Measurement of Solubilities of o-Phenylphenol in Petroleum Ether and DDP in Acetone + Water Solution

    Institute of Scientific and Technical Information of China (English)

    WANG Li-sheng; LONG Bing-wen; XIONG You-qing; WU Jun-sheng; KANG Hui-bao

    2006-01-01

    [(6-oxide-6H-dibenze(c, e)(1, 2) oxaphosphorin-6-yl) methyl]-butanedioic acid (DDP) was prepared and characterized. Solubilities of o-phenylphenol(OPP) in petroleum ether and DDP in acetone + water solution were measured by a gravimetrical method. The solubility data of OPP were well correlated using Francis equation. For the solubility of DDP in acetone aqueous solution, it was found that at each fixed temperature there existed a maximum when the acetone mass fraction in the solvent reached a certain concentration. The experiment shows that the fraction is approximately 0.6. The solubility data would be helpful for their industrial crystallization process.

  13. Selection of excipients for melt extrusion with two poorly water-soluble drugs by solubility parameter calculation and thermal analysis.

    Science.gov (United States)

    Forster, A; Hempenstall, J; Tucker, I; Rades, T

    2001-09-11

    The aim of this study was to determine the miscibility of drug and excipient to predict if glass solutions are likely to form when drug and excipient are melt extruded. Two poorly water-soluble drugs, indomethacin and lacidipine, were selected along with 11 excipients (polymeric and non-polymeric). Estimation of drug/excipient miscibility was performed using a combination of the Hoy and Hoftzyer/Van Krevelen methods for Hansen solubility parameter calculation. Miscibility was experimentally investigated with differential scanning calorimetry (DSC) and hot stage microscopy (HSM). Studies were performed at drug/excipient ratios, 1:4, 1:1 and 4:1. Analysis of the glass transition temperature (T(g)) was performed by quench cooling drug/excipient melts in the DSC. Differences in the drug/excipient solubility parameters of 10 MPa(1/2) were expected to indicate a lack of miscibility and not form glass solutions when melt extruded. Experimentally, miscibility was shown by changes in drug/excipient melting endotherms and confirmed by HSM investigations. Experimental results were in agreement with solubility parameter predictions. In addition, drug/excipient combinations predicted to be largely immiscible often exhibited more than one T(g) upon reheating in the DSC. Melt extrusion of miscible components resulted in amorphous solid solution formation, whereas extrusion of an "immiscible" component led to amorphous drug dispersed in crystalline excipient. In conclusion, combining calculation of Hansen solubility parameters with thermal analysis of drug/excipient miscibility can be successfully applied to predict formation of glass solutions with melt extrusion.

  14. 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...

  15. Water soluble nanocurcumin extracted from turmeric challenging the microflora from human oral cavity.

    Science.gov (United States)

    Gopal, Judy; Muthu, Manikandan; Chun, Se-Chul

    2016-11-15

    Water soluble nanocurcumin prepared from commercial turmeric powders was compared against ethanol extracted curcumin particles. The oral microflora from five different human volunteers was collected and the efficacy of solvent extracted curcumin versus water extracted nanocurcumin was demonstrated. Nanocurcumin activity against oral microflora confirms its antimicrobial potency. Confocal laser scanning microscopic results revealed the enhanced entry of nanocurcumin particles into microbial cells. The nanosized nature of nanocurcumin appears to have led to increased cellular interaction and thereby efficient destruction of microbial cells in the mouth. In addition, solubility of nanocurcumin is also believed to be a crucial factor behind its successful antimicrobial activity. This study proves that the bioactivity of a compound is greatly influenced by its solubility in water. This work recommends the use of water soluble nanocurcumin (extracted from turmeric) as potent substitute for curcumin in dental formulations.

  16. Thermoresponsive synergistic hydrogen bonding switched by several guest units in a water-soluble polymer.

    Science.gov (United States)

    Hao, Zhenhua; Li, Guangxiang; Yang, Ke; Cai, Yuanli

    2013-03-12

    Thermoresponsive synergistic hydrogen bonding (H-bonding) switched by several guest units in a water-soluble polymer is reported. Adjusting the distribution of guest units can effectively change the synergistic H-bonding inside polymer chains, thus widely switch the preorganization and thermoresponsive behavior of a water-soluble polymer. The synergistic H-bonding is also evidenced by converting less polar aldehyde groups into water-soluble oxime groups, which bring about the lowering-down of cloud point and an amplified hysteresis effect. This is a general approach toward the wide tunability of thermosensitivity of a water-soluble polymer simply by adjusting the distribution of several guest H-bonding units.

  17. Synthesis and Characterization of Water-Soluble Carboxymethyl-Cyclodextrin Polymer as Capillary Electrophoresis Chiral Selector

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The water-soluble carboxymethyl-cyclodextrin polymer (CM-CD polymer) was synthesized and used as capillary electrophoresis chiral selector.Verrapamil and thiopentorusodium were well separated using CM-CD polymer as chiral selector.

  18. Hydroaminomethylation of 1-Dodecene Catalyzed by Water-soluble Rhodium Complex

    Institute of Scientific and Technical Information of China (English)

    Ying Yong WANG; Mei Ming LUO; Yao Zhong LI; Hua CHEN; Xian Jun LI

    2004-01-01

    The hydroaminomethylation of 1-dodecene catalyzed by water soluble rhodium complex RhCl(CO)(TPPTS)2 in the presence of surfactant CTAB was investigated. High reactivity and selectivity for tertiary amine were achieved under relatively mild conditions.

  19. 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...

  20. 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

  1. Molecular Dynamics Simulations of the Solubility of H2S and CO2 in Water

    OpenAIRE

    Roberto López Rendón; José Alejandre

    2008-01-01

    We have performed molecular dynamics simulations at constant temperature and pressure to calculate the solubility of carbon dioxide (CO2) and hydrogen sulfide (H2S) in water. The solubility of gases in water is important in several technological problems, in particular in the petroleum industry. The calculated liquid densities as function of temperature are in good agreement with experimental data. The results at the liquid-vapor equilibrium show that at low temperatures there is an important...

  2. Synthesis and Cytotoxic Activity of Novel Water-soluble Prodrugs of Combretastatin A-4

    Institute of Scientific and Technical Information of China (English)

    Zhi Quan YONG; Xiao Ping XU; Ying Chun CHEN; Xu BAO; Ling Ling WENG; Hu ZHENG

    2006-01-01

    Novel water-soluble prodrugs of combretastatin A-4 (5-8) were synthesized and evaluated for their in vitro cytotoxicity against lung carcinoma A549. Compound 5, bearing phosphoryl choline (PC) moiety, showed 90% inhibition at 32 μg/mL concentration after 24 h. The findings showed the PC derivative would be a promising candidate for the development of new water-soluble prodrug of cytotoxic combretastatin A-4.

  3. Prediction of water solubilities for selected PCDDs/PCCDFs with COSMO-RS model

    Energy Technology Data Exchange (ETDEWEB)

    Oleszek-Kudlak, S.; Grabda, M.; Shibata, E.; Nakamura, T. [Inst. of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku Univ., Sendai (Japan); Rosik-Dulewska, C. [Inst. of Environmental Engineering of the Polish Academy of Sciences, Zabrze (Poland)

    2004-09-15

    Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are well identified contaminants ubiquitous in the environment. Of the various parameters that affect the fate and behavior of environmental organic compounds, water solubility is one of the most important. However, when we are studying the aqueous behavior of organic chemicals, we should also take into consideration and evaluate several parameters (temperature, salinity, dissolved organic matter) influencing their solubility. Among the 210 congeners (mono- to octa-chlorinated) of PCDDs and PCDFs, water solubility values are available for a few congeners only. The reported aqueous solubilities of PCDDs and PCDFs are often scattered, despite most of them having been measured by the generator column method, recognized as the most accurate for the determination of the water solubility of hydrophobic organic chemicals. These discrepancies reflect an important problem associated with difficulties in the preparation of the saturated solution and in the analytical measurements, particularly of compounds with a solubility below 1 ppb. In practice, the high cost of the experimental determinations also limits the field of research. In recent years, investigators have developed a number of calculational methods to predict the water solubility of organic chemicals. One of them is the Conductor-like Screening Model for Real Solvents (COSMO-RS) introduced by Klamt et al. This model was successfully used for finding the solubilities of chlorobenzenes (ClBZs) at a wider range of temperatures (from 5 to 60 C) and in a salty environment. In this study, we have applied COSMO-RS to determine the aqueous solubilities of 19 PCDDs/ PCDFs at 25 C. Additionally, we measured the solubilities of 7 PCDDs/PCDFs using the generator column method at 25 C. We used these data and those available from the literature to estimate the accuracy of the COSMO-RS calculations.

  4. High-Resolution Electrospray Ionization Mass Spectrometry Analysis of Water- Soluble Organic Aerosols Collected with a Particle into Liquid Sampler

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, Adam P.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

    2010-10-01

    This work demonstrates the utility of a particle-into-liquid sampler (PILS) a technique traditionally used for identification of inorganic ions present in ambient or laboratory aerosols for the analysis of water soluble organic aerosol (OA) using high resolution electrospray ionization mass spectrometry (HR ESI-MS). Secondary organic aerosol (SOA) was produced from 0.5 ppm mixing ratios of limonene and ozone in a 5 m3 Teflon chamber. SOA was collected simultaneously using a traditional filter sampler and a PILS. The filter samples were later extracted with either water or acetonitrile, while the aqueous PILS samples were analyzed directly. In terms of peak intensities, types of detectable compounds, average O:C ratios, and organic mass to organic carbon ratios, the resulting high resolution mass spectra were essentially identical for the PILS and filter based samples. SOA compounds extracted from both filter/acetonitrile extraction and PILS/water extraction accounted for >95% of the total ion current in ESI mass spectra. This similarity was attributed to high solubility of limonene SOA in water. In contrast, significant differences in detected ions and peak abundances were observed for pine needle biomass burning organic aerosol (BBOA) collected with PILS and filter sampling. The water soluble fraction of BBOA is considerably smaller than for SOA, and a number of unique peaks were detectable only by the filter/acetonitrile method. The combination of PILS collection with HR-ESI-MS analysis offers a new approach for molecular analysis of the water-soluble organic fraction in biogenic SOA, aged photochemical smog, and BBOA.

  5. Solubility of Stevioside and Rebaudioside A in water, ethanol and their binary mixtures

    Directory of Open Access Journals (Sweden)

    Liliana S. Celaya

    2016-10-01

    Full Text Available In order to investigate the solubility of Stevioside and Rebaudioside A in different solvents (ethanol, water, ethanol:water 30:70 and ethanol:water 70:30, supersaturated solutions of pre-crystalized steviol glycosides were maintained at different temperatures (from 5 °C to 50 °C to reach equilibrium. Under these conditions significant differences were found in the extent of solubility. Rebaudioside A was poorly soluble in ethanol and water, and Stevioside was poorly soluble in water. Solvent mixtures more effectively promoted solubilisation, and a significant effect of temperature on solubility was observed. The two steviol glycosides showed higher solubilities and this behavior was promoted by the presence of the other sweetener. The polarity indices of the solvents were determined, and helped to explain the observed behavior. Several solute-solvent and solute-solute interactions can occur, along with the incidence of a strong affinity between solvents. The obtained results are in accordance with technological applications of ethanol, water and their binary mixtures for Stevioside and Rebaudioside A separations.

  6. Buckminsterfullerene's (C60) octanol-water partition coefficient (Kow) and aqueous solubility.

    Science.gov (United States)

    Jafvert, Chad T; Kulkarni, Pradnya P

    2008-08-15

    To assess the risk and fate of fullerene C60 in the environment, its water solubility and partition coefficients in various systems are useful. In this study, the log Kow of C60 was measured to be 6.67, and the toluene-water partition coefficient was measured at log Ktw = 8.44. From these values and the respective solubilities of C60 in water-saturated octanol and water-saturated toluene, C60's aqueous solubility was calculated at 7.96 ng/L(1.11 x 10(-11) M) for the organic solvent-saturated aqueous phase. Additionally, the solubility of C60 was measured in mixtures of ethanol-water and tetrahydrofuran-water and modeled with Wohl's equation to confirm the accuracy of the calculated solubility value. Results of a generator column experiment strongly support the hypothesis that clusters form at aqueous concentrations below or near this calculated solubility. The Kow value is compared to those of other hydrophobic organic compounds, and bioconcentration factors for C60 were estimated on the basis of Kow.

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

    African Journals Online (AJOL)

    Bioassay using the water soluble fraction of a Nigerian Light Crude oil on Clarias ... Heavy metal and total hydrocarbon contents of the water and fish were ... THC concentrations in fish were higher at 96 hours and 14days than in the water ...

  8. WATER ACTIVITY DATA ASSESSMENT TO BE USED IN HANFORD WASTE SOLUBILITY CALCULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    DISSELKAMP RS

    2011-01-06

    The purpose of this report is to present and assess water activity versus ionic strength for six solutes:sodium nitrate, sodium nitrite, sodium chloride, sodium carbonate, sodium sulfate, and potassium nitrate. Water activity is given versus molality (e.g., ionic strength) and temperature. Water activity is used to estimate Hanford crystal hydrate solubility present in the waste.

  9. Photocatalytic hydrogen production from a simple water-soluble [FeFe]-hydrogenase model system.

    Science.gov (United States)

    Cao, Wei-Ning; Wang, Feng; Wang, Hong-Yan; Chen, Bin; Feng, Ke; Tung, Chen-Ho; Wu, Li-Zhu

    2012-08-21

    Combined with a simple water soluble [FeFe]-hydrogenase mimic 1, Ru(bpy)(3)(2+) and ascorbic acid enable hydrogen production photocatalytically. More than 88 equivalents of H(2) were achieved in water, which is much better than that obtained in an organic solvent or a mixture of organic solvent and water.

  10. Multiple sources of soluble atmospheric iron to Antarctic waters

    Science.gov (United States)

    Winton, V. H. L.; Edwards, R.; Delmonte, B.; Ellis, A.; Andersson, P. S.; Bowie, A.; Bertler, N. A. N.; Neff, P.; Tuohy, A.

    2016-03-01

    The Ross Sea, Antarctica, is a highly productive region of the Southern Ocean. Significant new sources of iron (Fe) are required to sustain phytoplankton blooms in the austral summer. Atmospheric deposition is one potential source. The fractional solubility of Fe is an important variable determining Fe availability for biological uptake. To constrain aerosol Fe inputs to the Ross Sea region, fractional solubility of Fe was analyzed in a snow pit from Roosevelt Island, eastern Ross Sea. In addition, aluminum, dust, and refractory black carbon (rBC) concentrations were analyzed, to determine the contribution of mineral dust and combustion sources to the supply of aerosol Fe. We estimate exceptionally high dissolved Fe (dFe) flux of 1.2 × 10-6 g m-2 y-1 and total dissolvable Fe flux of 140 × 10-6 g m-2 y-1 for 2011/2012. Deposition of dust, Fe, Al, and rBC occurs primarily during spring-summer. The observed background fractional Fe solubility of ~0.7% is consistent with a mineral dust source. Radiogenic isotopic ratios and particle size distribution of dust indicates that the site is influenced by local and remote sources. In 2011/2012 summer, relatively high dFe concentrations paralleled both mineral dust and rBC deposition. Around half of the annual aerosol Fe deposition occurred in the austral summer phytoplankton growth season; however, the fractional Fe solubility was low. Our results suggest that the seasonality of dFe deposition can vary and should be considered on longer glacial-interglacial timescales.

  11. Experimental study on desorption of soluble matter as influenced by cations in static water

    Institute of Scientific and Technical Information of China (English)

    Wen-sheng XU; Li CHEN; Xiao-xia TONG; Xiao-ping CHEN; Ping-cang ZHANG

    2014-01-01

    With variation of drainage basin environments, desorption of soluble matter has become one of the significant erosion processes in rivers. It has a considerable impact on flow and sediment transport, as well as processes of river bed deformation and landform evolution throughout a watershed. In this study, considering influences on sediment movement, especially on cohesive sediment transport, Ca2+ and H+ were chosen as characteristic ions of soluble matter, and the total desorption quantity of Ca2+ and pH value when the desorption equilibrium is reached were employed as two indexes representing the desorption of soluble matter. By means of an indoor experiment, desorption of soluble matter as influenced by cations in static water was investigated. The results show that the total desorption quantity of soluble matter increases with the initial cation concentration until a maximum desorption quantity value is obtained and maintained. The total desorption quantity of soluble matter depends on properties of the specific cations in static water, and the stronger the affinity is between the cation and sediment surface, the higher the total desorption quantity will be. Finally, a strong approximate linear relationship between desorption quantities for different kinds of soluble matters was obtained, which means that variation of pH values can accurately reflect the desorption results of soluble matter.

  12. Prediction of solubilities for ginger bioactive compounds in hot water by the COSMO-RS method

    Science.gov (United States)

    Zaimah Syed Jaapar, Syaripah; Azian Morad, Noor; Iwai, Yoshio

    2013-04-01

    The solubilities in water of four main ginger bioactives, 6-gingerol, 6-shogaol, 8-gingerol and 10-gingerol, were predicted using a conductor-like screening model for real solvent (COSMO-RS) calculations. This study was conducted since no experimental data are available for ginger bioactive solubilities in hot water. The σ-profiles of these selected molecules were calculated using Gaussian software and the solubilities were calculated using the COSMO-RS method. The solubilities of these ginger bioactives were calculated at 50 to 200 °C. In order to validate the accuracy of the COSMO-RS method, the solubilities of five hydrocarbon molecules were calculated using the COSMO-RS method and compared with the experimental data in the literature. The selected hydrocarbon molecules were 3-pentanone, 1-hexanol, benzene, 3-methylphenol and 2-hydroxy-5-methylbenzaldehyde. The calculated results of the hydrocarbon molecules are in good agreement with the data in the literature. These results confirm that the solubilities of ginger bioactives can be predicted using the COSMO-RS method. The solubilities of the ginger bioactives are lower than 0.0001 at temperatures lower than 130 °C. At 130 to 200 °C, the solubilities increase dramatically with the highest being 6-shogaol, which is 0.00037 mole fraction, and the lowest is 10-gingerol, which is 0.000039 mole fraction at 200 °C.

  13. Method of immobilizing water-soluble bioorganic compounds on a capillary-porous carrier

    Science.gov (United States)

    Ershov, Gennady Moiseevich; Timofeev, Eduard Nikolaevich; Ivanov, Igor Borisovich; Florentiev, Vladimir Leonidovich; Mirzabekov, Andrei Darievich

    1998-01-01

    The method for immobilizing water-soluble bioorganic compounds to capillary-porous carrier comprises application of solutions of water-soluble bioorganic compounds onto a capillary-porous carrier, setting the carrier temperature equal to or below the dew point of the ambient air, keeping the carrier till appearance of water condensate and complete swelling of the carrier, whereupon the carrier surface is coated with a layer of water-immiscible nonluminescent inert oil and is allowed to stand till completion of the chemical reaction of bonding the bioorganic compounds with the carrier.

  14. Antibacterial effect of water-soluble chitosan on representative dental pathogens Streptococcus mutans and Lactobacilli brevis

    Directory of Open Access Journals (Sweden)

    Chih-Yu Chen

    2012-12-01

    Full Text Available Dental caries is still a major oral health problem in most industrialized countries. The development of dental caries primarily involves Lactobacilli spp. and Streptococcus mutans. Although antibacterial ingredients are used against oral bacteria to reduce dental caries, some reports that show partial antibacterial ingredients could result in side effects. OBJECTIVES: The main objective is to test the antibacterial effect of water-soluble chitosan while the evaluation of the mouthwash appears as a secondary aim. MATERIAL AND METHODS: The chitosan was obtained from the Application Chemistry Company (Taiwan. The authors investigated the antibacterial effects of water-soluble chitosan against oral bacteria at different temperatures (25-37ºC and pH values (pH 5-8, and evaluated the antibacterial activities of a self-made water-soluble chitosan-containing mouthwash by in vitro and in vivo experiments, and analyzed the acute toxicity of the mouthwashes. The acute toxicity was analyzed with the pollen tube growth (PTG test. The growth inhibition values against the logarithmic scale of the test concentrations produced a concentrationresponse curve. The IC50 value was calculated by interpolation from the data. RESULTS: The effect of the pH variation (5-8 on the antibacterial activity of water-soluble chitosan against tested oral bacteria was not significant. The maximal antibacterial activity of water-soluble chitosan occurred at 37ºC. The minimum bactericidal concentration (MBC of water-soluble chitosan on Streptococcus mutans and Lactobacilli brevis were 400 µg/mL and 500 µg/mL, respectively. Only 5 s of contact between water-soluble chitosan and oral bacteria attained at least 99.60% antibacterial activity at a concentration of 500 µg/mL. The water-soluble chitosan-containing mouthwash significantly demonstrated antibacterial activity that was similar to that of commercial mouthwashes (>99.91% in both in vitro and in vivo experiments. In addition

  15. Solubility and permeability of steroids in water in the presence of potassium halides.

    Science.gov (United States)

    Messner, M; Loftsson, T

    2010-02-01

    Water forms a network of hydrogen bonded water molecules that gives liquid water unique physicochemical properties. Ions that affect the network structure, e.g. potassium halides, are known to either increase or decrease aqueous solubilities of drugs. Most biological membranes consist of hydrophilic exterior and a lipophilic interior. Mathematically they can be treated as two-layer membranes, i.e. a hydrophilic water layer that is referred to as unstirred water layer (UWL) and a lipophilic membrane. The purpose of this study was to investigate if and then how ions affect drug permeation through the UWL. The effects of potassium halides on the solubility and permeability of dexamethasone and hydrocortisone was investigated. The potassium halides had either increasing or decreasing effect on their aqueous solubility but did not have any effect on their permeability through UWL.

  16. Development of water soluble binder systems for low pressure injection molding of alumina

    Energy Technology Data Exchange (ETDEWEB)

    Bakan, H.I.; Gunes, M. [TUBITAK-MRC Materials and Chemical Technologies Research Inst., Kocaeli (Turkey)

    2004-07-01

    Low pressure injection molding of alumina powder using a water-soluble binder system has been carried out successfully. The water-soluble based binder system consisted of poly (2-ethyl-2-oxaline), low density polyethylene and stearic acid. The critical powder loading of the binder-powder mixture was determined based on torque rheometry experiments. The rheological properties of the powder-binder mixture were investigated systematically. The binder system used provides satisfactory mixture stability, excellent mouldability and reasonably fast water leaching and thermal debinding rates. The water-soluble constituent, poly (2-ethyl-2-oxaline), was removed by leaching in convecting water at 60 C within 6 hour. The remaining binder constituents were thermally removed during heating to 450 C. Sintering of the parts was conducted at 1550 C for an hour in air. (orig.)

  17. 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.

  18. Versatile particles from water-soluble chitosan and sodium alginate for loading toxic or bioactive substance.

    Science.gov (United States)

    You, Rongrui; Xiao, Congming; Zhang, Li; Dong, Yanrui

    2015-08-01

    Versatile hydrogel particles were obtained by cross-linking of water-soluble chitosan (WSC) with sodium alginate (SA) in an acid-free medium. The structure of the particles was investigated with Fourier transform infrared spectra, differential scanning calorimetry and thermogravimetric analysis. These characterization results confirmed that the product was physically cross-linked hydrogel consisted of WSC and SA. It was found that the swelling ratio of the particles depended on the formation time, which indicated that their cross-linking degrees were easily modulated. The particles showed high capability to bind heavy metal ions, acidic gas and basic gas. The adsorption capacities of the particles could reach 88.2 and 66.0 mg/g for Cu(2+) and Pb(2+), 33.8 and 30.3 mg/g for NH3 and H2S, respectively. Especially, the existence of water significantly enhanced the adsorption capacities for NH3 and H2S. In addition, the mild formation condition made the particles suitable for encapsulating bioactive substance. The loading efficiency of the beads for hemoglobin (HB) reached close to 100%. Moreover, the release behavior of the HB-loaded particles was pH-sensitive. In contrast, HB was deactivated during encapsulating it with chitosan and sodium alginate. Obviously, such a kind of particles was an attractive adsorbent or carrier. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Dynamical Coupling of Intrinsically Disordered Proteins and Their Hydration Water: Comparison with Folded Soluble and Membrane Proteins

    Science.gov (United States)

    Gallat, F.-X.; Laganowsky, A.; Wood, K.; Gabel, F.; van Eijck, L.; Wuttke, J.; Moulin, M.; Härtlein, M.; Eisenberg, D.; Colletier, J.-P.; Zaccai, G.; Weik, M.

    2012-01-01

    Hydration water is vital for various macromolecular biological activities, such as specific ligand recognition, enzyme activity, response to receptor binding, and energy transduction. Without hydration water, proteins would not fold correctly and would lack the conformational flexibility that animates their three-dimensional structures. Motions in globular, soluble proteins are thought to be governed to a certain extent by hydration-water dynamics, yet it is not known whether this relationship holds true for other protein classes in general and whether, in turn, the structural nature of a protein also influences water motions. Here, we provide insight into the coupling between hydration-water dynamics and atomic motions in intrinsically disordered proteins (IDP), a largely unexplored class of proteins that, in contrast to folded proteins, lack a well-defined three-dimensional structure. We investigated the human IDP tau, which is involved in the pathogenic processes accompanying Alzheimer disease. Combining neutron scattering and protein perdeuteration, we found similar atomic mean-square displacements over a large temperature range for the tau protein and its hydration water, indicating intimate coupling between them. This is in contrast to the behavior of folded proteins of similar molecular weight, such as the globular, soluble maltose-binding protein and the membrane protein bacteriorhodopsin, which display moderate to weak coupling, respectively. The extracted mean square displacements also reveal a greater motional flexibility of IDP compared with globular, folded proteins and more restricted water motions on the IDP surface. The results provide evidence that protein and hydration-water motions mutually affect and shape each other, and that there is a gradient of coupling across different protein classes that may play a functional role in macromolecular activity in a cellular context. PMID:22828339

  20. PRESENCE OF WATER-SOLUBLE COMPOUNDS IN THERMALLY MODIFIED WOOD: CARBOHYDRATES AND FURFURALS

    Directory of Open Access Journals (Sweden)

    Olov Karlsson,

    2012-06-01

    Full Text Available With thermal modification, changes in properties of wood, such as the presence of VOC and water-soluble carbohydrates, may occur. Thermal modifications under saturated steam conditions (160 °C or 170 °C and superheated steam conditions (170, 185, and 212 °C were investigated by analysing the presence of water-soluble 5-(hydroxymethylfurfural (HMF, furfural, and carbohydrates in heat-treated wood. The influence of thermal modifications on Scots pine, Norway spruce, and silver birch was also studied. Furfurals were analysed using HPLC at 280 nm, while monosaccharides and water-soluble carbohydrates were determined by GC-FID as their acetylated alditiols and, after methanolysis, as their trimethylsilylated methyl-glycosides, respectively. The amount of furfurals was larger in boards thermally modified under saturated steam conditions than those treated under superheated steam conditions. Generally, more of HMF than furfural was found in the thermally modified boards. In process water, in which saturated steam conditions had been used, furfural and only traces of HMF were found. Higher content of water-soluble carbohydrates was found in boards treated in saturated steam rather than in superheated steam. After modification in saturated steam, substantial parts of the water-soluble carbohydrates were due to monosaccharides, but only traces of monosaccharides were found in boards treated under superheated steam conditions.

  1. Water sorption and solubility of dental composites and identification of monomers released in an aqueous environment.

    Science.gov (United States)

    Ortengren, U; Wellendorf, H; Karlsson, S; Ruyter, I E

    2001-12-01

    Water sorption and solubility of six proprietary composite resin materials were assessed, and monomers eluted from the organic matrix during water storage identified. Water sorption and solubility tests were carried out with the following storage times: 4 h, 24 h and 7, 60 and 180 days. After storage, water sorption and solubility were determined. Eluted monomers were analysed by high performance liquid chromatography (HPLC). Correlation between the retention time of the registered peak and the reference peak was observed, and UV-spectra confirmed the identity. The results showed an increase in water sorption until equilibrium for all materials with one exception. The solubility behaviour of the composite resin materials tested revealed variations, with both mass decrease and increase. The resin composition influences the water sorption and solubility behaviour of composite resin materials. The HPLC analysis of eluted components revealed that triethyleneglycol dimethacrylate (TEGDMA) was the main monomer released. Maximal monomer concentration in the eluate was observed after 7 days. During the test period, quantifiable quantities of urethanedimethacrylate (UEDMA) monomer were observed, whereas 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)-phenyl]propane (Bis-GMA) was only found in detectable quantities. No detectable quantities of bisphenol-A were observed during the test period.

  2. Modified water solubility of milk protein concentrate powders through the application of static high pressure treatment.

    Science.gov (United States)

    Udabage, Punsandani; Puvanenthiran, Amirtha; Yoo, Jin Ah; Versteeg, Cornelis; Augustin, Mary Ann

    2012-02-01

    The effects of high pressure (HP) treatment (100-400 MPa at 10-60 °C) on the solubility of milk protein concentrate (MPC) powders were tested. The solubility, measured at 20 °C, of fresh MPC powders made with no HP treatment was 66%. It decreased by 10% when stored for 6 weeks at ambient temperature (~20 °C) and continued to decrease to less than 50% of its initial solubility after 12 months of storage. Of the combinations of pressure and heat used, a pressure of 200 MPa at 40 °C applied to the concentrate before spray drying was found to be the most beneficial for improved solubility of MPC powders. This combination of pressure/heat improved the initial cold water solubility to 85%. The solubility was maintained at this level after 6 weeks storage at ambient temperature and 85% of the initial solubility was preserved after 12 months. The improved solubility of MPC powders on manufacture and on storage are attributed to an altered surface composition arising from an increased concentration of non-micellar casein in the milk due to HP treatment prior to drying. The improved solubility of high protein powders (95% protein) made from blends of sodium caseinate and whey protein isolate compared with MPC powders (~85% protein) made from ultrafiltered/diafiltered milk confirmed the detrimental role of micellar casein on solubility. The results suggest that increasing the non-micellar casein content by HP treatment of milk or use of blends of sodium caseinate and whey proteins are strategies that may be used to obtain high protein milk powders with enhanced solubility.

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

    Science.gov (United States)

    Pierce, Brian C; Wichmann, Jesper; Tran, Tam H; Cheetamun, Roshan; Bacic, Antony; Meyer, Anne S

    2016-06-25

    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 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 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 of soluble soy polysaccharides and opens a new range of opportunities for this abundant and underutilized material in future research and industrial applications.

  4. Design, synthesis and in vitro evaluation of novel water-soluble prodrugs of buparvaquone.

    Science.gov (United States)

    Mäntylä, Antti; Rautio, Jarkko; Nevalainen, Tapio; Keski-Rahkonen, Pekka; Vepsälainen, Jouko; Järvinen, Tomi

    2004-10-01

    Novel water-soluble phosphate prodrugs (2b-5b) of buparvaquone-oxime (1a) and buparvaquone-O-methyloxime (1b) were synthesized and evaluated in vitro as potential oral prodrugs against leishmaniasis. Buparvaquone-oxime (1a), and most probably also buparvaquone-O-methyloxime (1b), released the parent buparvaquone via a cytochrome P450-catalysed reaction. The prodrugs 2b-5b showed significantly higher aqueous solubilities (>4 mg/ml) than buparvaquone ( 8 days). Although buparvaquone-oxime (1a) has been shown to undergo a cytochrome P450-catalysed oxidation in liver microsomes to the parent buparvaquone and behave as a novel bioreversible prodrug, its usefulness is limited in oral drug delivery due to its poor aqueous solubility, like buparvaquone itself. Further phosphorylation of an oxime form of buparvaquone significantly increased water solubility, and this novel approach is therefore useful to improve physicochemical properties of drugs containing a ketone functional group.

  5. An experimental study on the solubility of copper bichloride in water vapor

    Institute of Scientific and Technical Information of China (English)

    SHANG LinBo; BI XianWu; HU RuiZhong; FAN WenLing

    2007-01-01

    Using the solubility method, the solubility of CuCl2 in liquid-undersaturated HCl-bearing water vapor was investigated experimentally at temperatures of 330-370℃ and pressures of 4.2-10 MPa. The results have shown that hydration could significantly enhance copper solubility and the concentrations of copper were positively correlated with PH2O. The solubility of copper in vapor phase increased with increasing PH2O at the constant temperature. CuCl2 was transported as hydrated species CuCl2(H2O)ngas in water vapor. The formation of complexes is proposed to be the result of the following reaction:CuCl2solid + nH2Ogas = CuCl2 (H2O)ngas The hydration number n decreased slightly with increasing temperature. Statistical hydration numbers are 4.0, 3.6 and 3.3 at 330, 350 and 370℃, respectively.

  6. Removal of soluble microbial products as the precursors of disinfection by-products in drinking water supplies.

    Science.gov (United States)

    Liu, Jin-Lin; Li, Xiao-Yan

    2015-01-01

    Water pollution worsens the problem of disinfection by-products (DBPs) in drinking water supply. Biodegradation of wastewater organics produces soluble microbial products (SMPs), which can be important DBP precursors. In this laboratory study, a number of enhanced water treatment methods for DBP control, including enhanced coagulation, ozonation, and activated carbon adsorption, were evaluated for their effectiveness in treating SMP-containing water for the DBP reduction purpose. The results show that enhanced coagulation with alum could remove SMPs only marginally and decrease the DBP formation potential (DBPFP) of the water by less than 20%. Although ozone could cause destruction of SMPs in water, the overall DBPFP of the water did not decrease but increased after ozonation. In contrast, adsorption by granular activated carbon could remove the SMP organics from water by more than 60% and reduce the DBPFP by more than 70%. It is apparent that enhanced coagulation and ozonation are not suitable for the removal of SMPs as DBP precursors from polluted water, although enhanced coagulation has been commonly used to reduce the DBP formation caused by natural organic matter. In comparison, activated carbon adsorption is shown as a more effective means to remove the SMP content from water and hence to control the wastewater-derived DBP problem in water supply.

  7. Water-soluble extracts from defatted sesame seed flour show antioxidant activity in vitro.

    Science.gov (United States)

    Ben Othman, Sana; Katsuno, Nakako; Kanamaru, Yoshihiro; Yabe, Tomio

    2015-05-15

    Defatted white and gold sesame seed flour, recovered as a byproduct after sesame oil extraction, was extracted with 70% ethanol to obtain polar-soluble crude extracts. The in vitro antioxidant activity of the extract was evaluated by DPPH free radical scavenging activity and oxygen radical absorbing capacity (ORAC). The polar-soluble crude extracts of both sesame seed types exhibited good antioxidant capacity, especially by the ORAC method with 34,720 and 21,700 μmol Trolox equivalent/100g of white and gold sesame seed extract, respectively. HPLC, butanol extraction, and UPLC-MS analyses showed that different compounds contributed to the antioxidant activity of the polar-soluble crude extracts. Sesaminol glycosides were identified in the butanol-soluble fractions; whereas, purified water-soluble fraction contained ferulic and vanillic acids. This study shows that hydrophilic antioxidants in the purified water-soluble fraction contributed to the antioxidant activity of white and gold sesame seed polar-soluble crude extracts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. A Preliminary Study of the Solubility of Copper in Water Vapor at Elevated Temperatures and Pressures

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In order to understand the capacity of water vapor to transport copper and its mechanism,using the solubility method, the solubility of copper in undersaturated water vapor was investigated experimentally at temperatures from 310 ℃ to 350 ℃ and pressures from 42 × 105 to 100 × 105 Pa. Results of these experiments show that the presence of water vapor increases the concentration of Cu in the gus. At a constant temperature, the solubility of copper increases with increasing water vapor pressure.Copper may exist as hydrated gaseous particles in the vapor phase, and the dissolution process can be denumber decreases with increasing temperature, varying from ~6 at 310 ℃, to ~5 at 330 ℃, and ~4at 350 ℃. The results show that interactions between gas-solvent H2O and copper will significantly enhance the dissolution and transport capacity of copper in the gas phase.

  9. Study on the sound absorption mechanism in gradient water-soluble polymer solution

    Institute of Scientific and Technical Information of China (English)

    WANG Yuansheng; YANG Xue; ZHU Jinhua; YAO Shuren

    2006-01-01

    Attention was paid to the study on the sound absorption mechanism of watersoluble polymer during dissolving. A specially designed water-soluble polymer coating was synthesized in our lab. The sound attenuation property was measured in sound tube. The results showed that the sound attenuation of the gradient polymer solution was larger than that of the uniform. Depending on the experimental result and the theory of sound wave propagation in layered medium, a mechanism of gradient water-soluble polymer solution was developed. This mechanism can be described as follows: a water-soluble polymer coating formed a concentration gradient layer when it was dissolved in water. This gradient layer led to multiple reflection and absorption of sound. Finally the sound energy was transferred into heat.

  10. Enhancement of solubility of poorly water soluble anti hypertensive drug by nanosizing approach

    Directory of Open Access Journals (Sweden)

    Divyesh Thakar

    2012-01-01

    Full Text Available The objective of this research study was to optimize formulation and process variables affecting characteristic of nanosuspension in bead milling process. In this study, the practically water-insoluble telmisartan was nanoground by using top down method i.e. media milling method. Here the media used is ZnO 2 beads. A variety of surface active agents were tested for their stabilizing effects. Formulation factors evaluated were ratio of polymer to drug, whereas process parameters were milling time and concentration of ZnO 2 beads. Different concentration of stabilizers such as poloxamer 188, poloxamer 407, HPMC E 15, PVP K30 and combination of stabilizers were used for preparation of telmisartan nanosuspension. Responses measured in this study include particle size measurement, particle size distribution and zeta potential.

  11. Water-soluble carbon nanotube compositions for drug delivery and medicinal applications

    Energy Technology Data Exchange (ETDEWEB)

    Tour, James M.; Lucente-Schultz, Rebecca; Leonard, Ashley; Kosynkin, Dmitry V.; Price, Brandi Katherine; Hudson, Jared L.; Conyers, Jr., Jodie L.; Moore, Valerie C.; Casscells, S. Ward; Myers, Jeffrey N.; Milas, Zvonimir L.; Mason, Kathy A.; Milas, Luka

    2014-07-22

    Compositions comprising a plurality of functionalized carbon nanotubes and at least one type of payload molecule are provided herein. The compositions are soluble in water and PBS in some embodiments. In certain embodiments, the payload molecules are insoluble in water. Methods are described for making the compositions and administering the compositions. An extended release formulation for paclitaxel utilizing functionalized carbon nanotubes is also described.

  12. 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, info

  13. 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) monosaccharide/me

  14. Water-soluble carbon nanotube compositions for drug delivery and medicinal applications

    Science.gov (United States)

    Tour, James M.; Lucente-Schultz, Rebecca; Leonard, Ashley; Kosynkin, Dmitry V.; Price, Brandi Katherine; Hudson, Jared L.; Conyers, Jr., Jodie L.; Moore, Valerie C.; Casscells, S. Ward; Myers, Jeffrey N.; Milas, Zvonimir L.; Mason, Kathy A.; Milas, Luka

    2014-07-22

    Compositions comprising a plurality of functionalized carbon nanotubes and at least one type of payload molecule are provided herein. The compositions are soluble in water and PBS in some embodiments. In certain embodiments, the payload molecules are insoluble in water. Methods are described for making the compositions and administering the compositions. An extended release formulation for paclitaxel utilizing functionalized carbon nanotubes is also described.

  15. Novel Water Soluble Fluorescent Trimethine Indocyanines Containing N-p-Carboxybenzyl Group

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Two fluorescent indocyanine dyes containing at least one p-carboxybenzyl group on the nitrogen atoms in the hetcrocyclic rings were designed and synthesized. Their absorption maxima were 549 nm and 551 nm in water respectively. They had good water solubility and photostability.

  16. Enhanced water-solubility and antibacterial activity of novel chitosan derivatives modified with quaternary phosphonium salt.

    Science.gov (United States)

    Zhu, Dan; Cheng, Honghao; Li, Jianna; Zhang, Wenwen; Shen, Yuanyuan; Chen, Shaojun; Ge, Zaochuan; Chen, Shiguo

    2016-04-01

    Chitosan (CS) has been widely recognized as an important biomaterial due to its good antimicrobial activity, biocompatibility and biodegradability. However, CS is insoluble in water in neutral and alkaline aqueous solution due to the linear aggregation of chain molecules and the formation of crystallinity. This is one of the key factors that limit its practical applications. Therefore, improving the solubility of CS in neutral and alkaline aqueous solution is a primary research direction for biomedical applications. In this paper, a reactive antibacterial compound (4-(2,5-Dioxo-pyrrolidin-1-yloxycarbonyl)-benzyl)-triphenyl-phosphonium bromide (NHS-QPS) was synthesized for chemical modification of CS, and a series of novel polymeric antimicrobial agents, N-quaternary phosphonium chitosan derivatives (N-QPCSxy, x=1-2,y=1-4) were obtained. The water solubilities and antibacterial activities of N-QPCSxy against Escherichia coli and Staphylococcus aureus were evaluated compare to CS. The water solubility of N-QPCSxy was all better than that of CS at neutral pH aqueous solution, particularly, N-QPCS14 can be soluble in water over the pH range of 3 to 12. The antibacterial activities of CS derivatives were improved by introducing quaternary phosphonium salt, and antibacterial activity of N-QPCSxy increases with degree of substitution. Overall, N-QPCS14 represents a novel antibacterial polymer material with good antibacterial activity, waters solubility and low cytotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. 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.

  18. Fabrication and Mechanical Characterization of Water-Soluble Resin-Coated Natural Fiber Green Composites

    Science.gov (United States)

    Manabe, Ken-Ichi; Hayakawa, Tomoyuki

    In this study, water-soluble biodegradable resin was introduced as a coating agent to improve the interfacial strength and then to fabricate a high-performance green composite with polylactic acid (PLA) and hemp yarn. Dip coating was carried out for hemp yarn and the green composites were fabricated by hot processing. The coated green composite achieves a high tensile strength of 117 MPa even though the fiber volume fraction is less than 30%. Interfacial shear strength (IFSS) was measured by a single fiber pull-out test, and the effect of water-soluble resin on the tensile properties of the composites was evaluated. As a result, when using coated natural bundles, the IFSS value is smaller than when using noncoated natural bundles. On the basis of observations of the fractured surface of composites and initial yarns using a scanning electron microscope (SEM), the effect of the impregnation of water-soluble resin into the natural bundles on the tensile strength is discussed in detail. It is found that water-soluble resin is effective in improving the mechanical properties of the composite, although the interfacial strength between PLA and water-soluble resin was decreased, and as a result, the tensile strength of green composites increases by almost 20%.

  19. Solubilization of poorly water-soluble compounds using amphiphilic phospholipid polymers with different molecular architectures.

    Science.gov (United States)

    Mu, Mingwei; Konno, Tomohiro; Inoue, Yuuki; Ishihara, Kazuhiko

    2017-06-29

    To achieve stable and effective solubilization of poorly water-soluble bioactive compounds, water-soluble and amphiphilic polymers composed of hydrophilic 2-methacryloyloxyethyl phosphorylcholine (MPC) units and hydrophobic n-butyl methacrylate (BMA) units were prepared. MPC polymers having different molecular architectures, such as random-type monomer unit sequences and block-type sequences, formed polymer aggregates when they were dissolved in aqueous media. The structure of the random-type polymer aggregate was loose and flexible. On the other hand, the block-type polymer formed polymeric micelles, which were composed of very stable hydrophobic poly(BMA) cores and hydrophilic poly(MPC) shells. The solubilization of a poorly water-soluble bioactive compound, paclitaxel (PTX), in the polymer aggregates was observed, however, solubilizing efficiency and stability were strongly depended on the polymer architecture; in other words, PTX stayed in the poly(BMA) core of the polymer micelle formed by the block-type polymer even when plasma protein was present in the aqueous medium. On the other hand, when the random-type polymer was used, PTX was transferred from the polymer aggregate to the protein. We conclude that water-soluble and amphiphilic MPC polymers are good candidates as solubilizers for poorly water-soluble bioactive compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. 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.

  1. 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

  2. Solubility of water in fluorocarbons: Experimental and COSMO-RS prediction results

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Mara G.; Carvalho, Pedro J. [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Santos, Luis M.N.B.F. [CIQ, Departamento de Quimica, Faculdade de Ciencias da Universidade do Porto, R. Campo Alegre 687, 4169-007 Porto (Portugal); Gomes, Ligia R. [REQUIMTE, Departamento de Quimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, P-4169-007 Porto (Portugal); Marrucho, Isabel M. [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Coutinho, Joao A.P., E-mail: jcoutinho@ua.p [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal)

    2010-02-15

    This work aims at providing experimental and theoretical information about the water-perfluorocarbon molecular interactions. For that purpose, experimental solubility results for water in cyclic and aromatic perfluorocarbons (PFCs), over the temperature range between (288.15 and 318.15) K, and at atmospheric pressure, were obtained and are presented. From the experimental solubility dependence on temperature, the partial molar solution and solvation thermodynamic functions such as Gibbs free energy, enthalpy and entropy were determined and are discussed. The process of dissolution of water in PFCs is shown to be spontaneous for cyclic and aromatic compounds. It is demonstrated that the interactions between the non-aromatic PFCs and water are negligible while those between aromatic PFCs and water are favourable. The COSMO-RS predictive capability was explored for the description of the water solubility in PFCs and others substituted fluorocompounds. The COSMO-RS is shown to be a useful model to provide reasonable predictions of the solubility values, as well as to describe their temperature and structural modifications dependence. Moreover, the molar Gibbs free energy and molar enthalpy of solution of water are predicted remarkably well by COSMO-RS while the main deviations appear for the prediction of the molar entropy of solution.

  3. Structural Characterization and Reactivity of Pyrogenic Water-Soluble Organic Matter Derived from Biomass Combustion

    Science.gov (United States)

    Norwood, M. J.; Louchouarn, P.; Kuo, L.

    2011-12-01

    Combustion processes, whether from natural or anthropogenic origin, are major sources of particulate matter (PM), black carbon (BC), and volatile organic carbon to the atmosphere as well as soils and aquatic environments. The ubiquitous presence of biomass combustion by-products in atmospheric particles and soils could potentially lead to a large transfer of pyrogenic water-soluble organic matter (Pyr-WSOM) to the surface of watersheds and aquatic systems. In spite of this, there is a dearth of studies that have characterized the sources, and particularly the fate, of Pyr-WSOM to aquatic systems. In the present study, Pyr-WSOM was extracted from plant-derived chars (feedstocks: honey mesquite, cordgrass, and loblolly pine) produced at a range of temperatures (150-850C), and were then characterized using elemental analyses and ATR-FTIR. Low temperature (250C) Pyr-WSOM, extracted from honey mesquite and cordgrass biochars, were then incubated with aliquots of filtered water from the Trinity River (TX) for one month under dark conditions. Consistent with prior studies on combustion molecular markers such as anhydrosugars and methoxylated phenols, the total amount of dissolved organic carbon (DOC) released from biochars peaks around 200-250C and then decreases with increasing temperature of combustion. Elemental and structural analyses of biochar-derived WSOM reflect the selective solubility of certain functional groups. For example, despite the predominance of aromatic units and soot structures in biochars formed at high temperatures, such functionalities are not as predominant in their respective Pyr-WSOM. In addition, the high proportion of O-containing functionalities suggests that Pyr-WSOM may be more biodegradable than the particulate residues of biomass combustion. Indeed, low temperature Pyr-WSOM decomposed rapidly with half-lives ranging ~30 days for total DOC to 4-5 days for specific molecular markers of biomass combustion. These rapid turnover rates are in

  4. Synthesis of water-soluble silicon-porphyrin: protolytic behaviour of axially coordinated hydroxy groups.

    Science.gov (United States)

    Remello, Sebastian Nybin; Kuttassery, Fazalurahman; Hirano, Takehiro; Nabetani, Yu; Yamamoto, Daisuke; Onuki, Satomi; Tachibana, Hiroshi; Inoue, Haruo

    2015-12-14

    A new water-soluble silicon(IV)-tetra(4-carboxyphenyl)porphyrin (SiTCPP) with silicon(iv), the second most abundant element on Earth, in the center of porphyrin was synthesized. Fundamental properties including protolytic behaviour of axially coordinating hydroxy groups, and electrochemical behaviour were characterized. The properties were compared with those of silicon(IV)-tetra(2,4,6-trimethylphenyl)porphyrin (SiTMP) and silicon(IV)-tetra(4-trifluoromethylphenyl)porphyrin (SiTFMPP) and discussed in respect to the electron donating/withdrawing effect of the substituents. Two axially coordinating hydroxy groups of SiTCPP exhibit a four-step protolytic behaviour under the acidic conditions along with a single step protolysis of peripheral carboxyl groups. Though SiTCPP and SiTFMPP did not show any reactivity in the photochemical oxygenation of a substrate with K2PtCl6 as a sacrificial electron acceptor, the first oxidation wave in the electrochemical process of SiTCPP and SiTFMPP showed catalytic behaviour in aqueous acetonitrile solution at any pH condition, in contrast to SiTMP which has only a reversible oxidation wave under neutral and weakly acidic conditions. The criteria for the electrochemical oxidative activation of water and the photooxygenation of the substrate were obtained. The higher oxidation wave of Si-porphyrins than ∼0.86 volt vs. SHE is required for the electrochemical oxidation of water, while suitable protecting groups such as a methyl substituent is a requisite for the photochemical oxygenation with K2PtCl6 as a sacrificial electron acceptor.

  5. Solubility of methane, nitrogen, and carbon dioxide in bitumen and water for SAGD modelling

    Energy Technology Data Exchange (ETDEWEB)

    Al-Murayri, M.T.; Harding, T.G.; Maini, B.B.

    2011-07-15

    The steam assisted gravity-drainage (SAGD) process is a technology used in unconventional reservoirs to enhance oil recovery, this technique sometimes uses the co-injection of noncondensable gases (NCGs). The co-injection of NCGs with steam is used to reduce energy consumption and greenhouse gas emissions in SAGD, but this technique also affects the performance of SAGD, making the knowledge of gas solubility in bitumen and water important. This study was undertaken to develop a systematic approach to predict the K-values for the gas-bitumen and gas water phase equilibria at different temperatures and pressures. This research has been carried out by using different existing correlations. It has been observed that the Mehrotra and Svrcek gas-solubility correlation should be used to calculate NCG's solubility in bitumen and that NCGs' solubility in water could be calculated with Harvey's correlation. This study defined successfully an approach to calculate NCGs' solubility in bitumen and water.

  6. Coaxial electrospinning for encapsulation and controlled release of fragile water-soluble bioactive agents.

    Science.gov (United States)

    Jiang, Hongliang; Wang, Liqun; Zhu, Kangjie

    2014-11-10

    Coaxial electrospinning is a robust technique for one-step encapsulation of fragile, water-soluble bioactive agents, including growth factors, DNA and even living organisms, into core-shell nanofibers. The coaxial electrospinning process eliminates the damaging effects due to direct contact of the agents with organic solvents or harsh conditions during emulsification. The shell layer serves as a barrier to prevent the premature release of the water-soluble core contents. By varying the structure and composition of the nanofibers, it is possible to precisely modulate the release of the encapsulated agents. Promising work has been done with coaxially electrospun non-woven mats integrated with bioactive agents for use in tissue engineering, in local delivery and in wound healing, etc. This paper reviews the origins of the coaxial electrospinning method, its updated status and potential future developments for controlled release of the class of fragile, water-soluble bioactive agents.

  7. Effect of thatch on water-soluble phosphorus of pasture soil fertilized with broiler litter

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 t@hm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kg@hm-2) of the cores with the thatch layer was higher than that (20 kg@hm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface.

  8. [Relationship of resistance to diseases and water-soluble amino acids in Konjac leaves].

    Science.gov (United States)

    Chen, Yongbo; Jiang, Qiaolong

    2008-05-01

    Reversed-phase high performance liquid chromatography was used to analyze water-soluble amino acids in the normal Amorphophallus Konjac, Amorphophallus albus, Amorphophallus bulbifer, and the soft rot Amorphophallus Konjac, to determine the relationship of the different soft-rot resistant Konjac varieties and the proportion and content of the multiple water-soluble amino acids. The results showed that there are remarkable differences in the content and proportion of water-soluble amino acids in different resistant varieties and the same variety of normal and diseased leaves of Amorphophallus. In this study, the bank of fingerprint 15 chromatogram was established and can be used to analyze the related characteristic peaks and the resistance of Amorphophallus.

  9. Characteristics of size-fractionated atmospheric metals and water-soluble metals in two typical episodes in Beijing

    Science.gov (United States)

    Wang, Qingqing; Ma, Yongliang; Tan, Jihua; Zheng, Naijia; Duan, Jingchun; Sun, Yele; He, Kebin; Zhang, Yuanxun

    2015-10-01

    The abundance and behaviour of metals and water-soluble metals (V, Cr, Mn, Fe, Cu, Zn, As, Sr, Ag, Cd, Sn, Sb, Ba and Pb) in size-fractionated aerosols were investigated during two typical episodes in Beijing. Water-soluble inorganic ions (Na+, K+, Mg2+, Ca2+, NH4+ , F-, Cl-, SO42- and NO3-) were also measured. Atmospheric metals and water-soluble metals were both found at high levels; for PM2.5, average As, Cr, Cd, Cu, Mn and Pb concentrations were 14.8, 203.3, 2.5, 18.5, 42.6 and 135.3 ng/m3, respectively, and their water-soluble components were 11.1, 1.7, 2.4, 14.5, 19.8 and 97.8 ng/m3, respectively. Daily concentrations of atmospheric metals and water-soluble metals were generally in accordance with particle mass. The highest concentrations of metals and water-soluble metals were generally located in coarse mode and droplet mode, respectively. The lowest mass of metals and water-soluble metals was mostly in Aitken mode. The water solubility of all metals was low in Aitken and coarse modes, indicating that freshly emitted metals have low solubility. Metal water solubility generally increased with the decrease in particle size in the range of 0.26-10 μm. The water solubility of metals for PM10 was: 50% ≤ Cd, As, Sb, Pb; 26% water-soluble metals and their water solubility increased when polluted air mass came from the near west, near north-west, south-west and south-east of the mainland, and decreased when clean air mass came from the far north-west and far due south. The influence of dust-storms and clean days on water-soluble metals and size distribution was significant; however, the influence of rainfall was negligible. Aerosols with high concentrations of SO42- , K+ and NH4+ might indicate increased potential for human health effects because of their high correlation with water-soluble metals. Industrial emissions contribute substantially to water-soluble metal pollution as water-soluble metals show higher correlation with Cd, Sn, Sb and Pb that are mainly

  10. 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.

  11. The effect of the cation alkyl chain branching on mutual solubilities with water and toxicities

    Science.gov (United States)

    Kurnia, Kiki A.; Sintra, Tânia E.; Neves, Catarina M. S. S.; Shimizu, Karina; Lopes, José N. Canongia; Gonçalves, Fernando; Ventura, Sónia P. M.; Freire, Mara G.; Santos, Luís M. N. B. F.; Coutinho, João A. P.

    2014-01-01

    The design of ionic liquids has been focused on the cation-anion combinations but other more subtle approaches can be used. In this work the effect of the branching of the cation alkyl chain on the design of ionic liquids (ILs) is evaluated. The mutual solubilities with water and toxicities of a series of bis(trifluoromethylsulfonyl)-based ILs, combined with imidazolium, pyridinium, pyrrolidinium, and piperidinium cations with linear or branched alkyl chains, are reported. The mutual solubility measurements were carried out in the temperature range from (288.15 to 323.15) K. From the obtained experimental data, the thermodynamic properties of the solution (in the water-rich phase) were determined and discussed. The COnductor like Screening MOdel for Real Solvents (COSMO-RS) was used to predict the liquid-liquid equilibrium. Furthermore, molecular dynamic simulations were also carried out aiming to get a deeper understanding of these fluids at the molecular level. The results show that the increase in the number of atoms at the cation ring (from five to six) leads to a decrease in the mutual solubilities with water while increasing their toxicity, and as expected from the well-established relationship between toxicities and hydrophobicities of ILs. The branching of the alkyl chain was observed to decrease the water solubility in ILs, while increasing the ILs solubility in water. The inability of COSMO-RS to correctly predict the effect of branching alkyl chains toward water solubility on them was confirmed using molecular dynamic simulations to be due to the formation of nano-segregated structures of the ILs that are not taken into account by the COSMO-RS model. In addition, the impact of branched alkyl chains on the toxicity is shown to be not trivial and to depend on the aromatic nature of the ILs. PMID:25119425

  12. 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.

  13. Solubility and solution thermodynamics of 2,5-thiophenedicarboxylic acid in (water + ethanol) binary solvent mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yang; Zhang, Qi; Cao, Cuicui; Cheng, Limin [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China); Shi, Ying [Taiyuan Qiaoyou Chemical Industrial Co. Ltd., Taiyuan 030025 (China); Yang, Wenge [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China); Hu, Yonghong, E-mail: yonghonghu11@126.com [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China)

    2014-09-20

    Highlights: • The solubility increased with increasing temperature. • The solubility decreased with the rise of the ratio of the water. • The solubility data were fitted using Apelblat equation, CNIBS/R–K and JA model. • The Gibbs energy, enthalpy and entropy were calculated by the van’t Hoff analysis. - Abstract: In this paper, we focused on solubility and solution thermodynamics of 2,5-thiophenedicarboxylic acid. By gravimetric method, the solubility of 2,5-thiophenedicarboxylic acid was measured in (water + ethanol) binary solvent mixtures from 278.15 K to 333.15 K under atmosphere pressure. The solubility data were fitted using modified Apelblat equation, a variant of the combined nearly ideal binary solvent/Redlich–Kister (CNIBS/R–K) model and Jouyban–Acree model. Computational results showed that the modified Apelblat equation has the lowest MD (mean deviation). In addition, the thermodynamic properties of the solution process, including the Gibbs energy, enthalpy, and entropy were calculated by the van’t Hoff analysis.

  14. 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...

  15. 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.

  16. Hydrogen production by a hyperthermophilic membrane-bound hydrogenase in water-soluble nanolipoprotein particles.

    Science.gov (United States)

    Baker, Sarah E; Hopkins, Robert C; Blanchette, Craig D; Walsworth, Vicki L; Sumbad, Rhoda; Fischer, Nicholas O; Kuhn, Edward A; Coleman, Matt; Chromy, Brett A; Létant, Sonia E; Hoeprich, Paul D; Adams, Michael W W; Henderson, Paul T

    2009-06-10

    Hydrogenases constitute a promising class of enzymes for ex vivo hydrogen production. Implementation of such applications is currently hindered by oxygen sensitivity and, in the case of membrane-bound hydrogenases (MBHs), poor water solubility. Nanolipoprotein particles (NLPs) formed from apolipoproteins and phospholipids offer a novel means of incorporating MBHs into a well-defined water-soluble matrix that maintains the enzymatic activity and is amenable to incorporation into more complex architectures. We report the synthesis, hydrogen-evolving activity, and physical characterization of the first MBH-NLP assembly. This may ultimately lead to the development of biomimetic hydrogen-production devices.

  17. Similar Energetic Contributions of Packing in the Core of Membrane and Water-Soluble Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Joh, Nathan H.; Oberai, Amit; Yang, Duan; Whitelegge, Julian P.; Bowie, James U.; (UCLA)

    2009-09-15

    A major driving force for water-soluble protein folding is the hydrophobic effect, but membrane proteins cannot make use of this stabilizing contribution in the apolar core of the bilayer. It has been proposed that membrane proteins compensate by packing more efficiently. We therefore investigated packing contributions experimentally by observing the energetic and structural consequences of cavity creating mutations in the core of a membrane protein. We observed little difference in the packing energetics of water and membrane soluble proteins. Our results imply that other mechanisms are employed to stabilize the structure of membrane proteins.

  18. Water-Soluble Silicon Quantum Dots with Quasi-Blue Emission

    Science.gov (United States)

    Wang, Yun; Wang, Hao; Guo, Jun; Wu, Jiang; Gao, Li J.; Sun, Ying H.; Zhao, J.; Zou, Gui F.

    2015-07-01

    In this study, water-soluble silicon quantum dots have quasi-blue emission at 390 nm by being capped with 1-vinylimidazole in resese micelles. As-obtained silicon quantum dots have a diameter of 2~5 nm and high crystallinity. The quasi-blue emission of the silicon quantum dots is likely attributed to the polarity of the capping ligands. Moreover, the silicon quantum dots are water-soluble and have photoluminescence nanosecond decay time, suggesting their potential application in biological field.

  19. 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.

  20. Quantitative approaches for the description of solubilities of inorganic compounds in near-critical and supercritical water

    NARCIS (Netherlands)

    Leusbrock, Ingo; Metz, Sybrand J.; Rexwinkel, Glenn; Versteeg, Geert F.

    2008-01-01

    The decreased solubility of salts in supercritical water is of great interest for industrial applications and scientific work. Several methods to quantify this decreased solubility are described and reviewed by applying them on experimental solubility data. The salts used for comparison are NaCl, N

  1. Quantitative approaches for the description of solubilities of inorganic compounds in near-critical and supercritical water

    NARCIS (Netherlands)

    Leusbrock, Ingo; Metz, Sybrand J.; Rexwinkel, Glenn; Versteeg, Geert F.

    2008-01-01

    The decreased solubility of salts in supercritical water is of great interest for industrial applications and scientific work. Several methods to quantify this decreased solubility are described and reviewed by applying them on experimental solubility data. The salts used for comparison are NaCl, Na

  2. Size-resolved particulate water-soluble organic compounds in the urban, mountain and marine atmosphere

    Directory of Open Access Journals (Sweden)

    G. Wang

    2010-07-01

    Full Text Available Primary (i.e., sugars and sugar alcohols and secondary water-soluble organic compounds (WSOCs (i.e., dicarboxylic acids and aromatic acids were characterised on a molecular level in size-segregated aerosols from the urban and mountain atmosphere of China and from the marine atmosphere in the outflow region of East Asia. Levoglucosan is the most abundant WSOCs in the urban and mountain atmosphere, whose accumulated concentrations in all stages are 1–3 orders of magnitude higher than those of marine aerosols. In contrast, malic, succinic and phthalic acids are dominant in the marine aerosols, which are 3–6 times more abundant than levoglucosan. This suggests that a continuous formation of secondary organic aerosols is occurring in the marine atmosphere during the long-range transport of air mass from inland China to the North Pacific. Sugars and sugar-alcohols, except for levoglucosan, gave a bimodal size distribution in the urban and mountain areas, peaking at 0.7–1.1 μm and >3.3 μm, and a unimodal distribution in the marine region, peaking at >3.3 μm. In contrast, levoglucosan and all the secondary WSOCs, except for benzoic and azelaic acids, showed a unimodal size distribution with a peak at 0.7–1.1 μm. Geometric mean diameters (GMDs of the WSOCs in fine particles (<2.1 μm at the urban site are larger in winter than in spring, due to an enhanced coagulation effect under the development of an inversion layer. However, GMDs of levoglucosan and most of the secondary WSOCs in the coarse mode are larger in the mountain and marine air and smaller in the urban air. This is most likely caused by an enhanced hygroscopic growth due to the high humidity of the mountain and marine atmosphere.

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

    Science.gov (United States)

    1983-09-01

    low on the basis of comparison to the dynamic headspace analysis data (Table IV.) The best estimates of the levels of aromatic hydrocarbons appear to...0.2 0.1 a determined by dynamic headspace analysis (see Table 3). bincludes ethylbenzene and xylenes. 6 Table III. Chemical Composition of the Water

  4. Solubilization of the poorly water soluble drug, telmisartan, using supercritical anti-solvent (SAS) process.

    Science.gov (United States)

    Park, Junsung; Cho, Wonkyung; Cha, Kwang-Ho; Ahn, Junhyun; Han, Kang; Hwang, Sung-Joo

    2013-01-30

    Telmisartan is a biopharmaceutical classification system (BCS) class II drug that has extremely low water solubility but is freely soluble in highly alkalized solutions. Few organic solvents can dissolve telmisartan. This solubility problem is the main obstacle achieving the desired bioavailability. Because of its unique characteristics, the supercritical anti-solvent (SAS) process was used to BCS class II drug in a variety of ways including micronization, amorphization and solid dispersion. Solid dispersions were prepared using hydroxypropylmethylcellulose/polyvinylpyrrolidone (HPMC/PVP) at 1:0.5, 1:1, and 1:2 weight ratios of drug to polymer, and pure telmisartan was also treated using the SAS process. Processed samples were characterized for morphology, particle size, crystallinity, solubility, dissolution rate and polymorphic stability. After the SAS process, all samples were converted to the amorphous form and were confirmed to be hundreds nm in size. Solubility and dissolution rate were increased compared to the raw material. Solubility tended to increase with increases in the amount of polymer used. However, unlike the solubility results, the dissolution rate decreased with increases in polymer concentration due to gel layer formation of the polymer. Processed pure telmisartan showed the best drug release even though it had lower solubility compared to other solid dispersions; however, because there were no stabilizers in processed pure telmisartan, it recrystallized after 1 month under severe conditions, while the other solid dispersion samples remained amorphous form. We conclude that after controlling the formulation of solid dispersion, the SAS process could be a promising approach for improving the solubility and dissolution rate of telmisartan.

  5. Growth and Histopathological Effects of Chronic Exposition of Marine Pejerrey Odontesthes argentinensis Larvae to Petroleum Water-Soluble Fraction (WSF)

    National Research Council Canada - National Science Library

    Emeline Pereira Gusmão; Ricardo Vieira Rodrigues; Cauê Bonucci Moreira; Luis Alberto Romano; Luís André Sampaio; Kleber Campos Miranda-Filho

    2012-01-01

    The water-soluble fraction (WSF) of petroleum contains a mixture of polycyclic aromatic hydrocarbons, volatile hydrocarbons, phenols, and heterocyclic compounds, considered deleterious to aquatic biota...

  6. Supercritical fluid particle design for poorly water-soluble drugs (review).

    Science.gov (United States)

    Sun, Yongda

    2014-01-01

    Supercritical fluid particle design (SCF PD) offers a number of routes to improve solubility and dissolution rate for enhancing the bioavailability of poorly water-soluble drugs, which can be adopted through an in-depth knowledge of SCF PD processes and the molecular properties of active pharmaceutical ingredients (API) and drug delivery system (DDS). Combining with research experiences in our laboratory, this review focuses on the most recent development of different routes (nano-micron particles, polymorphic particles, composite particles and bio-drug particles) to improve solubility and dissolution rate of poorly water-soluble drugs, covering the fundamental concept of SCF and the principle of SCF PD processes which are typically used to control particle size, shape, morphology and particle form and hence enable notable improvement in the dissolution rate of the poorly water-soluble drugs. The progress of the industrialization of SCF PD processes in pharmaceutical manufacturing environment with scaled-up plant under current good manufacturing process (GMP) specification is also considered in this review.

  7. Water-soluble UV curable urethane methyl acrylate coating:preparation and properties

    Institute of Scientific and Technical Information of China (English)

    魏燕彦; 罗英武; 李宝芳; 李伯耿

    2004-01-01

    Two kinds of water-soluble and ultraviolet (UV) curable oligomers were synthesized and characterized. The oligomers were evaluated as resins for water-based UV curable coating. The rheology of the two oligomers' aqueous so-lutions was investigated in terms of solid fraction, pH dependence, and temperature dependence. The solutions were found to be Newtonian fluid showing rather low viscosity even at high solid fraction of 0.55. The drying process of the coatings and the properties of the cured coatings were studied by comparing them with water-dispersed UV-curable polyurethane methyl acrylate. It was evident that the water-soluble coating dried more slowly; and that the overall properties were inferior to those of the water-dispersed coating.

  8. Water-soluble UV curable urethane methyl acrylate coating:preparation and properties

    Institute of Scientific and Technical Information of China (English)

    魏燕彦; 罗英武; 李宝芳; 李伯耿

    2004-01-01

    Two kinds of water-soluble and ultraviolet (UV) curable oligomers were synthesized and characterized. The oligomers were evaluated as resins for water-based UV curable coating. The rheology of the two oligomers' aqueous solutions was investigated in terms of solid fraction, pH dependence, and temperature dependence. The solutions were found to be Newtonian fluid showing rather low viscosity even at high solid fraction of 0.55. The drying process of the coatings and the properties of the cured coatings were studied by comparing them with water-dispersed UV-curable polyurethane methyl acrylate. It was evident that the water-soluble coating dried more slowly; and that the overall properties were inferior to those of the water-dispersed coating.

  9. 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.

  10. Synthesis of water-dispersible silver nanoparticles by thermal decomposition of water-soluble silver oxalate precursors.

    Science.gov (United States)

    Togashi, Takanari; Saito, Kota; Matsuda, Yukiko; Sato, Ibuki; Kon, Hiroki; Uruma, Keirei; Ishizaki, Manabu; Kanaizuka, Katsuhiko; Sakamoto, Masatomi; Ohya, Norimasa; Kurihara, Masato

    2014-08-01

    Silver oxalate, one of the coordination polymer crystals, is a promising synthetic precursor for transformation into Ag nanoparticles without any reducing chemicals via thermal decomposition of the oxalate ions. However, its insoluble nature in solvents has been a great disadvantage, especially for systematic control of crystal growth of the Ag nanoparticles, while such control of inorganic nanoparticles has been generally performed using soluble precursors in homogeneous solutions. In this paper, we document our discovery of water-soluble species from the reaction between the insoluble silver oxalate and N,N-dimethyl-1,3-diaminopropane. The water-soluble species underwent low-temperature thermal decomposition of the oxalate ions at 30 °C with evolution of CO2 to reduce Ag+ to Ag0. Water-dispersible Ag nanoparticles have been successfully synthesized from the water-soluble species in the presence of gelatin via similar thermal decomposition at 100 °C. The gelatin-protected and water-dispersible Ag nanoparticles with a mean diameter of 25.1 nm appeared. In addition, antibacterial activity of the prepared water-dispersible Ag nanoparticles has been preliminarily investigated.

  11. Simulation of soluble waste transport and buildup in surface waters using tracers

    Science.gov (United States)

    Kilpatrick, F.A.

    1993-01-01

    Soluble tracers can be used to simulate the transport and dispersion of soluble wastes that might have been introduced or are planned for introduction into surface waters. Measured tracer-response curves produced from the injection of a known quantity of soluble tracer can be used in conjunction with the superposition principle to simulate potential waste buildup in streams, lakes, and estuaries. Such information is particularly valuable to environmental and water-resource planners in determining the effects of proposed waste discharges. The theory, techniques, analysis, and presentation of results of tracer-waste simulation tests in rivers, lakes, and estuaries are described. This manual builds on other manuals dealing with dye tracing by emphasizing the expanded use of data from time-of-travel studies.

  12. Filterable water-soluble organic nitrogen in fine particles over the southeastern USA during summer

    Science.gov (United States)

    Rastogi, Neeraj; Zhang, Xiaolu; Edgerton, Eric S.; Ingall, Ellery; Weber, Rodney J.

    2011-10-01

    Time integrated high-volume PM 2.5 samples were collected separately during day and night from 1 August to 10 September 2008 at a paired urban (Atlanta)-rural (Yorkville) sites as part of the August Mini-Intensive Gas and Aerosol Study (AMIGAS). Selected filters ( n = 96, 48 for each site) were analyzed for a suite of water-soluble chemical species, including major inorganic ions, water-soluble organic carbon (WSOC), water-soluble total and inorganic nitrogen (WSTN and WSIN), and levoglucosan. Semi-continuous analyses of PM 2.5 mass, soluble ions, WSOC, and gaseous O 3, SO 2, NO, NO 2, NO y, CO, and meteorological parameters were also carried out in parallel. This study focuses on the characteristics of filterable water-soluble organic nitrogen (WSON), estimated by the difference in the measured concentrations of WSTN and WSIN, determined from aqueous filter extracts. At both sites, WSON varied from below the limit of detection (25 ng-N m -3) to ˜600 ng-N m -3 and on average contributed ˜10% to WSTN mass, with the majority of soluble nitrogen being ammonium (˜82%). WSON:WSOC (or N:C) mass ratios ranged between 0 and 27% at both the sites with a median value of ˜5%, similar to what has been reported in another study in the southeastern USA. At both the urban and rural sites median nighttime levels of WSON and N:C were observed to be consistently higher than daytime values. Based on correlation analyses, daytime WSON sources appeared different than nighttime sources, especially at the urban site. Overall, the data suggest the importance of coal-combustion (e.g., link to SO 2), vehicle emissions, soil dust and biomass burning as WSON sources, and that nitrogenous organic compounds are likely a fairly small fraction of the secondary organic aerosol for this location during summer.

  13. The effects of fire temperatures on water soluble heavy metals.

    Science.gov (United States)

    Pereira, P.; Ubeda, X.; Martin, D. A.

    2009-04-01

    Fire ash are majority composed by base cations, however the mineralized organic matter, led also available to transport a higher quantity of heavy metals that potentially could increase a toxicity in soil and water resources. The amount availability of these elements depend on the environment were the fire took place, burning temperature and combusted tree specie. The soil and water contamination from fire ash has been neglected, because the majority of studies are focused on base cations dynamic. Our research, beside contemplate major elements, is focused in to study the behavior of heavy metals released from ash slurries created at several temperatures under laboratory environment, prescribed fires and wildland fires. The results presented in these communication are preliminary and study the presence of Aluminium (Al3+), Manganese (Mn2+), Iron (Fe2+) and Zinc (Zn2+) of ash slurries generated in laboratory environment at several temperatures (150°, 200°, 250°, 300°, 350°, 400°,450°, 500°, 550°C) from Quercus suber, Quercus robur, Pinus pinea and Pinus pinaster and from a low medium temperature prescribed fire in a forest dominated Quercus suber trees. We observed that ash produced at lower and medium temperatures (Quercus species and Mn2+ in Pinus ashes. Fe2+ and Zn2+ showed a reduced concentration in test solution in relation to unburned sample at all temperatures of exposition. In the results obtained from prescribed fire, we identify a higher release of Al3+ and a decrease of the remain elements. The solubilization of these elements are related with pH levels and ash calcite content, because their ability to capture ions in solution. Moreover, the amount and the type of ions released in relation to unburned sample vary in each specie. In this study Al3+ release is related with Quercus species and Mn2+ with Pinus species. Fire ashes can be an environmental problem, because at long term can increase soil acidity. After all base cations have being leached

  14. Water-soluble constituents of caraway: aromatic compound, aromatic compound glucoside and glucides.

    Science.gov (United States)

    Matsumura, Tetsuko; Ishikawa, Toru; Kitajima, Junichi

    2002-10-01

    From the water-soluble portion of the methanolic extract of caraway (fruit of Carum carvi L.), an aromatic compound, an aromatic compound glucoside and a glucide were isolated together with 16 known compounds. Their structures were clarified as 2-methoxy-2-(4'-hydroxyphenyl)ethanol, junipediol A 2-O-beta-D-glucopyranoside and L-fucitol, respectively.

  15. Measurement of solubility and water sorption of dental nanocomposites light cured by argon laser.

    Science.gov (United States)

    Mirsasaani, Seyed Shahabeddin; Ghomi, Farhad; Hemati, Mehran; Tavasoli, Tina

    2013-03-01

    Different parameters used for photoactivation process and also composition provide changes in the properties of dental composites. In the present work the effect of different power density of argon laser and filler loading on solubility (SL) and water sorption (WS) of light-cure dental nanocomposites was studied. The resin of nanocomposites was prepared by mixing bisphenol A glycol dimethacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) with a mass ratio of 65/35. 20 wt.% and 25 wt.% of nanosilica fillers with a primary particle size of 10 nm were added to the resin. Camphorquinone (CQ) and DMAEMA were added as photoinitiator system. The nanocomposites were cured by applying the laser beam at the wavelength of 472 nm and power densities of 260 and 340 mW/cm(2) for 40 sec. Solubility and water sorption were then measured according to ISO 4049, which in our case, the maximums were 2.2% and 4.3% at 260 mW/cm(2) and 20% filler, respectively. The minimum solubility (1.2%) and water sorption (3.8%) were achieved for the composite containing 25% filler cured at 340 mW/cm(2). The results confirmed that higher power density and filler loading decreased solubility of unreacted monomers and water sorption and improved physico-mechanical properties of nanocomposites.

  16. Water sorption and solubility of methacrylate resin-based root canal sealers.

    Science.gov (United States)

    Donnelly, Adam; Sword, Jeremy; Nishitani, Yoshihiro; Yoshiyama, Masahiro; Agee, Kelli; Tay, Franklin R; Pashley, David H

    2007-08-01

    The water sorption and solubility characteristics of three contemporary methacrylate resin-based endodontic sealers, EndoREZ, Epiphany, and InnoEndo, were compared with those obtained from Kerr EWT, Ketac-Endo (positive control), GuttaFlow, and AH Plus (both negative controls). Ten disks of each material were dehydrated in Drierite for 24 h and weighed to constant dry mass. They were placed in water and weighed periodically until maximum water sorption was obtained. The disks were dehydrated again to determine their mass loss (solubility) at equilibrium. Epiphany exhibited the highest apparent water sorption (8%) followed by Ketac-Endo (6.2%), InnoEndo (3.4%), EndoREZ (3.0%), AH Plus (1.1%), GuttaFlow (0.4%), and Kerr EWT (0.3%). Significantly higher solubility (3.5-4%) were observed for all three methacrylate resin-based sealers and Kerr EWT (3.95%), compared with Ketac-Endo (1.6%), AH Plus (0.16%), and GuttaFlow (0.13%). American Dental Association specifications require<3% solubility for endodontic sealers. Only Ketac-Endo, AH Plus, and GuttaFlow met that criterion.

  17. In vitro degradation of dermal sheep collagen cross-linked 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

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

  18. 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

  19. 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.

  20. 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

    1996-01-01

    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 non-cross-

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

    NARCIS (Netherlands)

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

    1996-01-01

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

  2. Temperature-dependent photoluminescence of highly luminescent water-soluble CdTe quantum dots

    Institute of Scientific and Technical Information of China (English)

    Ji Wei Liu; Yu Zhang; Cun Wang Ge; Yong Long Jin; Sun Ling Hu; Ning Gu

    2009-01-01

    Highly luminescent water-soluble CdTe quantum dots (QDs) have been synthesized with an electrogenerated precursor. The obtained CdTe QDs can possess good crystallizability, high quantum yield (QY) and favorable stability. Furthermore, a detection system is designed firstly for the investigation of the temperature-dependent PL of the QDs.

  3. Temperature and sodium chloride effects on the solubility of anthracene in water

    Energy Technology Data Exchange (ETDEWEB)

    Arias-Gonzalez, Israel [Instituto Mexicano del Petroleo, Direccion de Investigacion y Posgrado, Programa de Ingenieria Molecular, Area de Investigacion en Termofisica, Eje Central Lazaro Cardenas Norte 152. 07730, Mexico D.F. (Mexico); Reza, Joel, E-mail: jreza@imp.m [Instituto Mexicano del Petroleo, Direccion de Investigacion y Posgrado, Programa de Ingenieria Molecular, Area de Investigacion en Termofisica, Eje Central Lazaro Cardenas Norte 152. 07730, Mexico D.F. (Mexico); Trejo, Arturo, E-mail: atrejo@imp.m [Instituto Mexicano del Petroleo, Direccion de Investigacion y Posgrado, Programa de Ingenieria Molecular, Area de Investigacion en Termofisica, Eje Central Lazaro Cardenas Norte 152. 07730, Mexico D.F. (Mexico)

    2010-11-15

    The solubility of anthracene was measured in pure water and in sodium chloride aqueous solution (salt concentration, m/mol . kg{sup -1} = 0.1006, 0.5056, and 0.6082) at temperatures between (278 and 333) K. Solubility of anthracene in pure water agrees fairly well with values reported in earlier similar studies. Solubility of anthracene in sodium chloride aqueous solutions ranged from (6 . 10{sup -8} to 143 . 10{sup -8}) mol . kg{sup -1}. Sodium chloride had a salting-out effect on the solubility of anthracene. The salting-out coefficients did not vary significantly with temperature over the range studied. The average salting-out coefficient for anthracene was 0.256 kg . mol{sup -1}. The standard molar Gibbs free energies, {Delta}{sub tr}G{sup o}, enthalpies, {Delta}{sub tr}H{sup o}, and entropies, {Delta}{sub tr}S{sup o}, for the transfer of anthracene from pure water to sodium chloride aqueous solutions were also estimated. Most of the estimated {Delta}{sub tr}G{sup o} values were positive [(20 to 1230) J . mol{sup -1}]. The analysis of the thermodynamic parameters shows that the transfer of anthracene from pure water to sodium chloride aqueous solution is thermodynamically unfavorable, and that this unfavorable condition is caused by a decrease in entropy.

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

    NARCIS (Netherlands)

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

    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

  5. 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

  6. 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.

  7. Differences in dinucleotide frequencies of thermophilic genes encoding water soluble and membrane proteins

    Institute of Scientific and Technical Information of China (English)

    Hiroshi NAKASHIMA; Yuka KURODA

    2011-01-01

    The occurrence frequencies of the dinucleotides of genes of three thermophilic and three mesophilic species from both archaea and eubacteria were investigated in this study. The genes encoding water soluble proteins were rich in the dinucleotides of purine dimers, whereas the genes encoding membrane proteins were rich in pyrimidine dimers. The dinucleotides of purine dimers are the counterparts of pyrimidine dimers in a double-stranded DNA. The purine/pyrimidine dimers were favored in the thermophiles but not in the mesophiles, based on comparisons of observed and expected frequencies. This finding is in agreement with our previous study which showed that purine/pyrimidine dimers are positive factors that increase the thermal stability of DNA. The dinucleotides AA, AG, and GA are components of the codons of charged residues of Glu, Asp, Lys, and Arg, and the dinucleotides TT, CT, and TC are components of the codons of hydrophobic residues of Leu, He, and Phe. This is consistent with the suitabilities of the different amino acid residues for water soluble and membrane proteins. Our analysis provides a picture of how thermophilic species produce water soluble and membrane proteins with distinctive characters: the genes encoding water soluble proteins use DNA sequences rich in purine dimers, and the genes encoding membrane proteins use DNA sequences rich in pyrimidine dimers on the opposite strand.

  8. 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...

  9. 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...

  10. Water-soluble vitamin deficiencies in complicated peptic ulcer patients soon after ulcer onset in Japan.

    Science.gov (United States)

    Miyake, Kazumasa; Akimoto, Teppei; Kusakabe, Makoto; Sato, Wataru; Yamada, Akiyoshi; Yamawaki, Hiroshi; Kodaka, Yasuhiro; Shinpuku, Mayumi; Nagoya, Hiroyuki; Shindo, Tomotaka; Ueki, Nobue; Kusunoki, Masafumi; Kawagoe, Tetsuro; Futagami, Seiji; Tsukui, Taku; Sakamoto, Choitsu

    2013-01-01

    We investigated over time whether contemporary Japanese patients with complicated peptic ulcers have any water-soluble vitamin deficiencies soon after the onset of the complicated peptic ulcers. In this prospective cohort study, fasting serum levels of water-soluble vitamins (vitamins B1, B2, B6, B12, C, and folic acid) and homocysteine were measured at 3 time points (at admission, hospital discharge, and 3 mo after hospital discharge). Among the 20 patients who were enrolled in the study, 10 consecutive patients who completed measurements at all 3 time points were analyzed. The proportion of patients in whom any of the serum water-soluble vitamins that we examined were deficient was as high as 80% at admission, and remained at 70% at discharge. The proportion of patients with vitamin B6 deficiency was significantly higher at admission and discharge (50% and 60%, respectively, ppeptic ulcers may have a deficiency of one or more water-soluble vitamins in the early phase of the disease after the onset of ulcer complications, even in a contemporary Japanese population.

  11. CORAL: QSPR model of water solubility based on local and global SMILES attributes.

    Science.gov (United States)

    Toropov, Andrey A; Toropova, Alla P; Benfenati, Emilio; Gini, Giuseppina; Leszczynska, Danuta; Leszczynski, Jerzy

    2013-01-01

    Water solubility is an important characteristic of a chemical in many aspects. However experimental definition of the endpoint for all substances is impossible. In this study quantitative structure-property relationships (QSPRs) for negative logarithm of water solubility-logS (mol L(-1)) are built up for five random splits into the sub-training set (≈55%), the calibration set (≈25%), and the test set (≈20%). Simplified molecular input-line entry system (SMILES) is used as the representation of the molecular structure. Optimal SMILES-based descriptors are calculated by means of the Monte Carlo method using the CORAL software (http://www.insilico.eu/coral). These one-variable models for water solubility are characterized by the following average values of the statistical characteristics: n(sub_train)=725-763; n(calib)=312-343; n(test)=231-261; r(sub_train)(2)=0.9211±0.0028; r(calib)(2)=0.9555±0.0045; r(test)(2)=0.9365±0.0073; s(sub_train)=0.561±0.0086; s(calib)=0.453±0.0209; s(test)=0.520±0.0205. Thus, the reproducibility of statistical quality of suggested models for water solubility confirmed for five various splits. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Chemical characterization of extractable water soluble matter associated with PM10 from Mexico City during 2000.

    Science.gov (United States)

    Gutiérrez-Castillo, M E; Olivos-Ortiz, M; De Vizcaya-Ruiz, A; Cebrián, M E

    2005-11-01

    We report the chemical composition of PM10-associated water-soluble species in Mexico City during the second semester of 2000. PM10 samples were collected at four ambient air quality monitoring sites in Mexico City. We determined soluble ions (chloride, nitrate, sulfate, ammonium, sodium, potassium), ionizable transition metals (Zn, Fe, Ti, Pb, Mn, V, Ni, Cr, Cu) and soluble protein. The higher PM(10) levels were observed in Xalostoc (45-174 microg m(-3)) and the lowest in Pedregal (19-54 microg m(-3)). The highest SO2 average concentrations were observed in Tlalnepantla, NO2 in Merced and O3 and NO(x) in Pedregal. The concentration range of soluble sulfate was 6.7-7.9 and 19-25.5 microg m(-3) for ammonium, and 14.8-29.19 for soluble V and 3.2-7.7 ng m(-3) for Ni, suggesting a higher contribution of combustion sources. PM-associated soluble protein levels varied between 0.038 and 0.169 mg m(-3), representing a readily inhalable constituent that could contribute to adverse outcomes. The higher levels for most parameters studied were observed during the cold dry season, particularly in December. A richer content of soluble metals was observed when they were expressed by mass/mass units rather than by air volume units. Significant correlations between Ni-V, Ni-SO4(-2), V-SO4(-2), V-SO2, Ni-SO2 suggest the same type of emission source. The variable soluble metal and ion concentrations were strongly influenced by the seasonal meteoclimatic conditions and the differential contribution of emission sources. Our data support the idea that PM10 mass concentration by itself does not provide a clear understanding of a local PM air pollution problem.

  13. Sorption and solubility of ofloxacin and norfloxacin in water-methanol cosolvent.

    Science.gov (United States)

    Peng, Hongbo; Li, Hao; Wang, Chi; Zhang, Di; Pan, Bo; Xing, Baoshan

    2014-05-01

    Prediction of the properties and behavior of antibiotics is important for their risk assessment and pollution control. Theoretical calculation was incorporated in our experimental study to investigate the sorption of ofloxacin (OFL) and norfloxacin (NOR) on carbon nanotubes and their solubilities in water, methanol, and their mixture. Sorption for OFL and NOR decreased as methanol volume fractions (fc) increased. But the log-linear cosolvency model could not be applied as a general model to describe the cosolvent effect on OFL and NOR sorption. We computed the bond lengths of possible hydrogen bonds between solute and solvent and the corresponding interaction energies using Density Functional Theory. The decreased OFL solubility with increased fc could be attributed to the generally stronger hydrogen bond between OFL and H2O than that between OFL and CH3OH. Solubility of NOR varied nonmonotonically with increasing fc, which may be understood from the stronger hydrogen bond of NOR-CH3OH than NOR-H2O at two important sites (-O18 and -O21). The interaction energies were also calculated for the solute surrounded by solvent molecules at all the possible hydrogen bond sites, but it did not match the solubility variations with fc for both chemicals. The difference between the simulated and real systems was discussed. Similar sorption but different solubility of NOR and OFL from water-methanol cosolvent suggested that sorbate-solvent interaction seems not control their sorption.

  14. Soluble vs. insoluble fiber

    Science.gov (United States)

    Insoluble vs. soluble fiber; Fiber - soluble vs. insoluble ... There are 2 different types of fiber -- soluble and insoluble. Both are important for health, digestion, and preventing diseases. Soluble fiber attracts water and turns to gel during digestion. ...

  15. 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.

  16. Occurrence of selected volatile organic compounds and soluble pesticides in Texas public water-supply source waters, 1999-2001

    Science.gov (United States)

    Mahler, Barbara June; Canova, Michael G.; Gary, Marcus O.

    2002-01-01

    During 1999?2001, the U.S. Geological Survey, in cooperation with the Texas Natural Resource Conservation Commission, collected samples of untreated water from 48 public water-supply reservoirs and 174 public water-supply wells. The samples were analyzed for volatile organic compounds (VOCs) and soluble pesticides; in addition, well samples were analyzed for nitrite plus nitrate and tritium. This fact sheet summarizes the findings of the source-water sampling and analyses. Both VOCs and pesticides were detected much more frequently in surface water than in ground water. The only constituent detected at concentrations exceeding the maximum contaminant level for drinking water was nitrate. These results will be used in the Texas Source-Water Assessment Program to evaluate the susceptibility of public water-supply source waters to contamination.

  17. Phytoactivity of secondary compounds in aromatic plants by volatile and water-soluble ways of release

    OpenAIRE

    A. S. Dias; Dias, L. S.

    2005-01-01

    Phytoactivity should be expected as a generalized trait of secondary plant compounds if their primary role is defence against co-occurring plants, and volatilization should be their predominant way of release in dry climates while in wet climates water leaching should prevail. Bioassays were designed to compare the ability of volatiles and water-solubles of four aromatic species thriving in dry environments (Cistus salvifolius L., Foeniculum vulgare Miller, Myrtus communis L., and Rosmarinus ...

  18. Lipid-nanoemulsions as drug delivery carriers for poorly-water soluble drug

    OpenAIRE

    Veerendra K. Nanjwade; F. V. Manvi; Basavaraj K. Nanjwade; Katare, O P

    2013-01-01

    To enhance the bioavailability of the poorly water-soluble drug Aceclofenac, a lipidnanoemulsion comprising ethanolic solution of phospholipid 90 G and tween 80 in 1:1 ratio (Smix), triacetin and anseed oil as oil phase and distilled water as aqueous phase, in the ratio of 55:15:30 (% w/w) was developed by constructing pseudo-ternary phase diagrams and evaluated for viscosity, % transmittance, and surface morphology of nanoemulsions. In vitro diffusion (release) of Aceclofenac from three diff...

  19. Nanoformulation and encapsulation approaches for poorly water-soluble drug nanoparticles

    Science.gov (United States)

    Wais, Ulrike; Jackson, Alexander W.; He, Tao; Zhang, Haifei

    2016-01-01

    During the last few decades the nanomedicine sector has emerged as a feasible and effective solution to the problems faced by the high percentage of poorly water-soluble drugs. Decreasing the size of such drug compounds to the nanoscale can significantly change their physical properties, which lays the foundation for the use of nanomedicine for pharmaceutical applications. Various techniques have been developed to produce poorly water-soluble drug nanoparticles, mainly to address the poor water-soluble issues but also for the efficient and targeted delivery of such drugs. These techniques can be generally categorized into top-down, bottom-up and encapsulation approaches. Among them, the top-down approaches have been the main choice for industrial preparation of drug nanoparticles while other methods are actively investigated by researchers. In this review, we aim to give a comprehensive overview and latest progress of the top-down, bottom-up, and encapsulation methods for the preparation of poorly water-soluble drug nanoparticles and how solvents and additives can be selected for these methods. In addition to the more industrially applied top-down approaches, the review is focused more on bottom-up and encapsulation methods, particularly covering supercritical fluid-related methods, cryogenic techniques, and encapsulation with dendrimers and responsive block copolymers. Some of the approved and mostly used nanodrug formulations on the market are also covered to demonstrate the applications of poorly water-soluble drug nanoparticles. This review is complete with perspectives on the development and challenges of fabrication techniques for more effective nanomedicine.

  20. 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

    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...... 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...

  1. Amorphous solid dispersions and nano-crystal technologies for poorly water-soluble drug delivery.

    Science.gov (United States)

    Brough, Chris; Williams, R O

    2013-08-30

    Poor water-solubility is a common characteristic of drug candidates in pharmaceutical development pipelines today. Various processes have been developed to increase the solubility, dissolution rate and bioavailability of these active ingredients belonging to BCS II and IV classifications. Over the last decade, nano-crystal delivery forms and amorphous solid dispersions have become well established in commercially available products and industry literature. This article is a comparative analysis of these two methodologies primarily for orally delivered medicaments. The thermodynamic and kinetic theories relative to these technologies are presented along with marketed product evaluations and a survey of commercial relevant scientific literature.

  2. Water solubility of selected C9-C18 alkanes using a slow-stir technique: Comparison to structure - property models.

    Science.gov (United States)

    Letinski, Daniel J; Parkerton, Thomas F; Redman, Aaron D; Connelly, Martin J; Peterson, Brian

    2016-05-01

    Aqueous solubility is a fundamental physical-chemical substance property that strongly influences the distribution, fate and effects of chemicals upon release into the environment. Experimental water solubility was determined for 18 selected C9-C18 normal, branched and cyclic alkanes. A slow-stir technique was applied to obviate emulsion formation, which historically has resulted in significant overestimation of the aqueous solubility of such hydrophobic liquid compounds. Sensitive GC-MS based methods coupled with contemporary sample extraction techniques were employed to enable reproducible analysis of low parts-per billion aqueous concentrations. Water solubility measurements for most of the compounds investigated, are reported for the first time expanding available data for branched and cyclic alkanes. Measured water solubilities spanned four orders of magnitude ranging from 0.3 μg/L to 250 μg/L. Good agreement was observed for selected alkanes tested in this work and reported in earlier literature demonstrating the robustness of the slow-stir water solubility technique. Comparisons of measured alkane water solubilities were also made with those predicted by commonly used quantitative structure-property relationship models (e.g. SPARC, EPIWIN, ACD/Labs). Correlations are also presented between alkane measured water solubilities and molecular size parameters (e.g. molar volume, solvent accessible molar volume) affirming a mechanistic description of empirical aqueous solubility results and prediction previously reported for a more limited set of alkanes.

  3. Water solubility enhancements of pyrene by single and mixed surfactant solutions

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Water solubility enhancements of pyrene by both single-surfactant and mixed-surfactant solutions were compared andevaluated. The solubility of pyrene in water was greatly enhanced by each of Triton X-100 (TX100), Triton X-405 (TX405), Brij 35 and SDS, in which the water solubility enhancements increased with increasing surfactant concentrations. The extent of solubility enhancements at surfactant concentrations below the CMC is the order of TX100 > Brij 35 > TX405 > SDS; the sequence at surfactantconcentrations above the CMC is TX100 > Brij 35 > SDS > TX405. Pyrene was solubilized synergistically by anionic-nonionic mixed surfactant solutions, especially at low surfactant concentrations. The synergistic power of the mixed surfactants is SDS-TX405 > SDS-Brij 35 > SDS-TX100. The synergism as noted is attributed to increasing Kmc and/or decreasing the CMC of the mixed surfactan solution. For SDS-TX405 and SDS-Brij 35 mixed surfactant solutions, an increase in Kmc is coupled with a decrease in the CMC; for SDS-TX100, only a decreased in the CMC value is noted. Mixed-surfactant solutions may improve the performance of the surfactant-enhanced remediation (SER) of soils by increasing the bioavailability and biodegradation of non-aqueous-phase organic pollutants and reducing the level of surfactant pollution and remediation expenses.

  4. Temperature dependence of local solubility of hydrophobic molecules in the liquid-vapor interface of water.

    Science.gov (United States)

    Abe, Kiharu; Sumi, Tomonari; Koga, Kenichiro

    2014-11-14

    One important aspect of the hydrophobic effect is that solubility of small, nonpolar molecules in liquid water decreases with increasing temperature. We investigate here how the characteristic temperature dependence in liquid water persists or changes in the vicinity of the liquid-vapor interface. From the molecular dynamics simulation and the test-particle insertion method, the local solubility Σ of methane in the liquid-vapor interface of water as well as Σ of nonpolar solutes in the interface of simple liquids are calculated as a function of the distance z from the interface. We then examine the temperature dependence of Σ under two conditions: variation of Σ at fixed position z and that at fixed local solvent density around the solute molecule. It is found that the temperature dependence of Σ at fixed z depends on the position z and the system, whereas Σ at fixed local density decreases with increasing temperature for all the model solutions at any fixed density between vapor and liquid phases. The monotonic decrease of Σ under the fixed-density condition in the liquid-vapor interface is in accord with what we know for the solubility of nonpolar molecules in bulk liquid water under the fixed-volume condition but it is much robust since the solvent density to be fixed can be anything between the coexisting vapor and liquid phases. A unique feature found in the water interface is that there is a minimum in the local solubility profile Σ(z) on the liquid side of the interface. We find that with decreasing temperature the minimum of Σ grows and at the same time the first peak in the oscillatory density profile of water develops. It is likely that the minimum of Σ is due to the layering structure of the free interface of water.

  5. Ultraviolet-irradiation induced and spontaneous mutation of Rhizobium trifolii 11B in relation to water-soluble and water-insoluble polysaccharide production ability

    Energy Technology Data Exchange (ETDEWEB)

    Ghai, J.; Ghai, S.K.; Kalra, M.S. (Punjab Agricultural Univ., Ludhiana (India))

    1985-02-01

    Rhizobium trifolii 11B was u.v. irradiated and nine u.v. mutants have been isolated. Among the mutants, only one, R. trifolii 21M11B, produced more (752 mg/100 ml) water-soluble polysaccharide than the parent (704 mg/100 ml). The composition of water-soluble polysaccharide from u.v. mutants differed from that of the parent, R. trifolii 11B, and none of its u.v. mutants produced water-insoluble polysaccharide as detected by the Aniline Blue method. Storage of u.v. mutants for 2 months at 5/sup 0/C gave four spontaneous variants which acquired the ability to produce water-insoluble polysaccharide. The spontaneous mutants also retained their water-soluble polysaccharide producing ability. The water-soluble polysaccharide produced by these mutants was characterized as curdlan type. The chemistry of water-soluble and water-insoluble polysaccharides was also ascertained.

  6. Hydrodistillation-adsorption method for the isolation of water-soluble, non-soluble and high volatile compounds from plant materials.

    Science.gov (United States)

    Mastelić, J; Jerković, I; Blazević, I; Radonić, A; Krstulović, L

    2008-08-15

    Proposed method of hydrodistillation-adsorption (HDA) on activated carbon and hydrodistillation (HD) with solvent trap were compared for the isolation of water-soluble, non-soluble and high volatile compounds, such as acids, monoterpenes, isothiocyanates and others from carob (Certonia siliqua L.), rosemary (Rosmarinus officinalis L.) and rocket (Eruca sativa L.). Isolated volatiles were analyzed by GC and GC/MS. The main advantages of HDA method over ubiquitous HD method were higher yields of volatile compounds and their simultaneous separation in three fractions that enabled more detail analyses. This method is particularly suitable for the isolation and analysis of the plant volatiles with high amounts of water-soluble compounds. In distinction from previously published adsorption of remaining volatile compounds from distillation water on activated carbon, this method offers simultaneous hydrodistillation and adsorption in the same apparatus.

  7. Bioavailability Improvement Strategies for Poorly Water-Soluble Drugs Based on the Supersaturation Mechanism: An Update.

    Science.gov (United States)

    Yang, Meiyan; Gong, Wei; Wang, Yuli; Shan, Li; Li, Ying; Gao, Chunsheng

    2016-01-01

    The formulation development for poorly soluble drugs still remains a challenge. Supersaturating drug delivery systems (SDDS) or drug delivery systems based on supersaturating provide a promising way to improve the oral bioavailability of poorly water-soluble drugs. In supersaturable formulations, drug concentration exceeds the equilibrium solubility when exposed to gastrointestinal fluids, and the supersaturation state is maintained long enough to be absorbed, resulting in compromised bioavailability. In this article, the mechanism of generating and maintaining supersaturation and the evaluation methods of supersaturation assays are discussed. Recent advances in different drug delivery systems based on supersaturating are the focus and are discussed in detail.This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

  8. Solubility of cellulose in supercritical water studied by molecular dynamics simulations.

    Science.gov (United States)

    Tolonen, Lasse K; Bergenstråhle-Wohlert, Malin; Sixta, Herbert; Wohlert, Jakob

    2015-04-02

    The insolubility of cellulose in ambient water and most aqueous systems presents a major scientific and practical challenge. Intriguingly though, the dissolution of cellulose has been reported to occur in supercritical water. In this study, cellulose solubility in ambient and supercritical water of varying density (0.2, 0.7, and 1.0 g cm(-3)) was studied by atomistic molecular dynamics simulations using the CHARMM36 force field and TIP3P water. The Gibbs energy of dissolution was determined between a nanocrystal (4 × 4 × 20 anhydroglucose residues) and a fully dissociated state using the two-phase thermodynamics model. The analysis of Gibbs energy suggested that cellulose is soluble in supercritical water at each of the studied densities and that cellulose dissolution is typically driven by the entropy gain upon the chain dissociation while simultaneously hindered by the loss of solvent entropy. Chain dissociation caused density augmentation around the cellulose chains, which improved water-water bonding in low density supercritical water whereas the opposite occurred in ambient and high density supercritical water.

  9. Photophysical Properties and Singlet Oxygen Generation Efficiencies of Water-Soluble Fullerene Nanoparticles

    Science.gov (United States)

    Stasheuski, Alexander S; Galievsky, Victor A; Stupak, Alexander P; Dzhagarov, Boris M; Choi, Mi Jin; Chung, Bong Hyun; Jeong, Jin Young

    2014-01-01

    As various fullerene derivatives have been developed, it is necessary to explore their photophysical properties for potential use in photoelectronics and medicine. Here, we address the photophysical properties of newly synthesized water-soluble fullerene-based nanoparticles and polyhydroxylated fullerene as a representative water-soluble fullerene derivative. They show broad emission band arising from a wide-range of excitation energies. It is attributed to the optical transitions from disorder-induced states, which decay in the nanosecond time range. We determine the kinetic properties of the singlet oxygen (1O2) luminescence generated by the fullerene nanoparticles and polyhydroxylated fullerene to consider the potential as photodynamic agents. Triplet state decay of the nanoparticles was longer than 1O2 lifetime in water. Singlet oxygen quantum yield of a series of the fullerene nanoparticles is comparably higher ranging from 0.15 to 0.2 than that of polyhydroxylated fullerene, which is about 0.06. PMID:24893622

  10. 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.

  11. Biodegradation of the water-soluble gasoline components in a novel hybrid bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-De-Jesus, A.; Lara-Rodriguez, A.; Santoyo-Tepole, F.; Juarez-Ramirez, C.; Cristiani-Urbina, E.; Ruiz-Ordaz, N.; Galindez Mayer, J. [Escuela Nacional de Ciencias Biologicas, del Instituto Politecnico Nacional, Departamento de Ingenieria Bioquimica, Carpio y Plan de Ayala, ' ' Centro Operativo Naranjo' ' , Mexico, D.F. (Mexico)

    2003-07-01

    A novel hybrid bioreactor was designed to remove volatile organic compounds from water contaminated with water-soluble gasoline components, and the performance of this new bioreactor was investigated. It was composed of two biotrickling filter sections and one biofilter section. The liquid phase pollutants were removed by a mixed culture in the biotrickling filter sections and the gas phase pollutants stripped by air injection in the biofilter section. The specific rates of chemical oxygen demand (COD) removal obtained in the reactor were directly proportional to the pollutant-loading rate. A stable operation of the hybrid bioreactor was attained for long periods of time. The bioreactor had the potential to simultaneously treat a complex mixture of volatile organic compounds, e.g., those present in the water-soluble fraction of gasoline, as well as the capacity to readily adapt to changing operational conditions, such as an increased contaminant loading, and variations in the airflow rate. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  12. Enhanced water-solubility, antibacterial activity and biocompatibility upon introducing sulfobetaine and quaternary ammonium to chitosan.

    Science.gov (United States)

    Chen, Yuxiang; Li, Jianna; Li, Qingqing; Shen, Yuanyuan; Ge, Zaochuan; Zhang, Wenwen; Chen, Shiguo

    2016-06-05

    Chitosan (CS) has attracted much attention due to its good antibacterial activity and biocompatibility. However, CS is insoluble in neutral and alkaline aqueous solution, limiting its biomedical application to some extent. To circumvent this drawback, we have synthesized a novel N-quaternary ammonium-O-sulfobetaine-chitosan (Q3BCS) by introducing quaternary ammonium compound (QAC) and sulfobetaine, and its water-solubility, antibacterial activity and biocompatibility were evaluated compare to N-quaternary ammonium chitosan and native CS. The results showed that by introducing QAC, antibacterial activities and water-solubilities increase with degrees of substitution. The largest diameter zone of inhibition (DIZ) was improved from 0 (CS) to 15mm (N-Q3CS). And the water solution became completely transparent from pH 6.5 to pH 11; the maximal waters-solubility was improved from almost 0% (CS) to 113% at pH 7 (N-Q3CS). More importantly, by further introducing sulfobetaine, cell survival rate of Q3BCS increased from 30% (N-Q3CS) to 85% at 2000μg/ml, which is even greater than that of native CS. Furthermore, hemolysis of Q3BCS was dropped sharply from 4.07% (N-Q3CS) to 0.06%, while the water-solution and antibacterial activity were further improved significantly. This work proposes an efficient strategy to prepare CS derivatives with enhanced antibacterial activity, biocompatibility and water-solubility. Additionally, these properties can be finely tailored by changing the feed ratio of CS, glycidyl trimethylammonium chloride and NCO-sulfobetaine.

  13. Water solubility enhancements of PAHs by sodium castor oil sulfonate microemulsions

    Institute of Scientific and Technical Information of China (English)

    ZHU Li-zhong; ZHAO Bao-wei; LI Zong-lai

    2003-01-01

    Water solubility enhancements of naphthalene(Naph), phenantherene(Phen) and pyrene(Py) in sodium castor oil sulfonate(SCOS) microemulsions were evaluated. The apparent solubilities of PAHs are linearly proportional to the concentrations of SCOS microemulsion, and the enhancement extent by SCOS solutions is greater than that by ordinary surfactants on the basis of weight solubilization ratio(WSR). The logKem values of Naph, Phen, and Py are 3.13, 4.44 and 5.01 respectively, which are about the same as the logKow values. At 5000 mg/L of SCOS conccentration, the apparent solubilities are 8.80, 121, and 674 times as the intrinsic solubilities for Naph, Phen, and Py. The effects of inorganic ions and temperature on the solubilization of solutes are also investigated. The solubilization is improved with a moderate addition of Ca2+, Na+, NH4+ and the mixture of Na+, K+, Ca2+, Mg2+ and NH4+. WSR values are enhanced by 22.0% for Naph, 23.4% for Phen, and 24.6% for Py with temperature increasing by 5℃. The results indicated that SCOS microemulsions improve the performance of the surfactant-enhanced remediation(SER) of soil, by increasing solubilities of organic pollutants and reducing the level of surfactant pollution and remediation expenses.

  14. Enhanced bioavailability of the poorly water-soluble drug fenofibrate by using liposomes containing a bile salt.

    Science.gov (United States)

    Chen, Yaping; Lu, Yi; Chen, Jianming; Lai, Jie; Sun, Jing; Hu, Fuqiang; Wu, Wei

    2009-07-06

    The main purpose of this study was to evaluate oral bioavailability of the poorly water-soluble drug fenofibrate when liposomes containing a bile salt were used as oral drug delivery systems. Liposomes composed of soybean phosphotidylcholine (SPC) and sodium deoxycholate (SDC) were prepared by a dry-film dispersing method coupled with sonication and homogenization. Several properties of the liposomes, including particle size, entrapment efficiency and membrane fluidity, were extensively characterized. In vitro release experiments indicated that no more than 20% of total fenofibrate was released from SPC/cholesterol (CL) and SPC/SDC liposomes at 2 h, in contrast with near complete release for micronized fenofibrate capsules. Strikingly, in vivo measurements of pharmacokinetics and bioavailability demonstrated higher rates of fenofibrate absorption from both SPC/SDC and SPC/CL liposomes than micronized fenofibrate. The bioavailability of SPC/SDC and SPC/CL liposomes was 5.13- and 3.28-fold higher, respectively, than that of the micronized fenofibrate. The disparity between oral bioavailability and in vitro release for liposomes strongly suggests alternative absorption mechanisms rather than enhanced release. Importantly, SPC/SDC liposomes exhibited a 1.57-fold increase in bioavailability relative to SPC/CL liposomes, indicating that liposomes containing bile salts may be used to enhance oral bioavailability of poorly water-soluble drugs.

  15. Effect Of Pressure On The Temperature Dependence Of Water Solubility In Forsterite

    Science.gov (United States)

    Bali, E.; Bolfan-Casanova, N.; Koga, K.

    2005-12-01

    Water storage capacity of the upper mantle largely depends on water solubility in mantle olivine. Realistic models must take into account the simultaneous effects of variables such as pressure, temperature, iron content and silica activity. Previous experimental studies have shown that the water solubility in olivine increases with increasing water fugacity up to 12 GPa at 1100°C. Water incorporation in olivine was also observed to increase with increasing temperature and increasing iron content at 0.3 GPa, however the temperature dependence was not studied at higher pressures. Interestingly, the only high-pressure data available, that is for wadsleyite and ringwoodite, show that their water solubility decreases with increasing temperature. The goal of this study is to determine the dependence of water maximum concentration on temperature at pressures higher than 0.3 GPa. We performed experiments at 3 and 6 GPa, and temperatures ranging from 1000 to 1400°C in the MgO-SiO2-H2O system using a multi-anvil apparatus. The olivine and orthopyroxene molar ratio was 1 to 1 in the starting material with 5 wt% H2O. The samples were analyzed using scanning electron microscopy and Fourier transform infrared spectroscopy. The mineralogical assemblage consisted of olivine+orthopyroxene+fluid at temperatures below 1250°C both at 3 and 6 GPa and olivine+melt+/-orthopyroxene at higher temperatures. At 3 GPa, above 1325°C orthopyroxene was missing from the assemblage, whereas in case of the 6 GPa experiments it was present even at higher temperatures. This indicates a change in fluid composition from 3 to 6 GPa. Preliminary data using unpolarized FTIR measurements, but comparing same orientations, indicate that water solubility in olivine at 6 GPa decreases with increasing temperature. This observation agrees with the results on wadsleyite and ringwoodite, but contradict the results of the existing low-pressure data. The explaination we propose for the change in temperature

  16. 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

    Full Text Available Background: Quercetin, a flavonol contained in various vegetables and fruits, has various biological activities including anticancer, antiviral, anti-diabetic, and anti-oxidative. However, it has low oral bioavailability due to insolubility in water. Thus, the bioavailability of quercetin administered to human beings in a capsule form, was reported to be less than 1%, with only a small percentage of ingested quercetin getting absorbed in the blood. This leads to certain difficulties in creating highly effective medicines Methods: Quercetin-rubusoside and quercetin-rebaudioside were prepared. The antioxidant activities of quercetin and Q-rubusoside were evaluated by DPPH radical scavenging method. Inhibition activities of quercetin and Quercetin-rubusoside were determined by measuring the remaining activity of 3CLpro with 200 μM inhibitor. The inhibition activity of quercetin, rubusoside and quercetin-rubusoside were determined by measuring the activity of human maltase which remains at 100 μM rubusoside or quercetin-rubusoside. The mushroom tyrosinase inhibition was assayed with the reaction mixture contained 3.3 mM L-DOPA in 50 mM potassium phosphate buffer (pH 6.8, and 10 U mushroom tyrosinase/ml with or without quercetin or quercetin-rubusoside. Results: With 10% rubusoside treatment, quercetin showed solubility of 7.7 mg/ml in water, and its solubility increased as the concentration of rubusoside increased; the quercetin solubility in water increased to 0.83 mg/mlas rubusoside concentration increased to 1 mg/ml. Quercetin solubilized in rubusoside solution showed DPPH radical-scavenging activity and mushroom tyrosinase inhibition activity, similar to that of quercetin solubilized in dimethyl-sulfoxide. Quercetin-rubusoside also showed 1.2 and 1.9 folds higher inhibition activity against 3CLpro of SARS and human intestinal maltase, respectively, than those of quercetin in DMSO. Conclusions: Quercetin can be solubilized in water with

  17. Biodegradability of soil water soluble organic carbon extracted from seven different soils

    Institute of Scientific and Technical Information of China (English)

    SCAGLIA Barbara; ADANI Fabrizio

    2009-01-01

    Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water (soil/water ratio of 1:2, W/V) for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, adding useful information to soil fertility.

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

    Energy Technology Data Exchange (ETDEWEB)

    Leuenberger, H. [University of Basel, Pharmacenter, Institute of Pharmaceutical Technology (Switzerland)], E-mail: hans.leuenberger@unibas.ch

    2002-04-15

    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.

  19. Characterization of human monocyte activation by a water soluble preparation of Aphanizomenon flos-aquae.

    Science.gov (United States)

    Pugh, N; Pasco, D S

    2001-11-01

    Aphanizomenon flos-aquae (AFA) is a fresh-water microalgae that is consumed as a nutrient-dense food source and for its health-enhancing properties. The current research characterizes the effect of a water soluble preparation from AFA on human monocyte/macrophage function and compares the effect of AFA with responses from known agents that modulate the immune system. At 0.5 pg/ml the AFA extract robustly activated nuclear factor kappa B (NF-kappa B) directed luciferase expression in THP-1 human monocytic cells to levels at 50% of those achieved by maximal concentrations (10 microg/ml) of bacterial lipopolysaccharide (LPS). In addition, the AFA extract substantially increased mRNA levels of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), and enhanced the DNA binding activity of NF-kappa B. The effects of AFA water soluble preparation were similar to the responses displayed by LPS, but clearly different from responses exhibited by tetradecanoyl phorbol acetate (TPA) and interferon-gamma (INF-gamma). Pretreatment of THP-1 monocytes with factors known to induce hyporesponsiveness suppressed both AFA-dependent and LPS-dependent activation. These results suggest that the macrophage-activating properties of the AFA water soluble preparation are mediated through pathways that are similar to LPS-dependent activation.

  20. Evidence of soluble microbial products accelerating chloramine decay in nitrifying bulk water samples.

    Science.gov (United States)

    Bal Krishna, K C; Sathasivan, Arumugam; Chandra Sarker, Dipok

    2012-09-01

    The discovery of a microbially derived soluble product that accelerates chloramine decay is described. Nitrifying bacteria are believed to be wholly responsible for rapid chloramine loss in drinking water systems. However, a recent investigation showed that an unidentified soluble agent significantly accelerated chloramine decay. The agent was suspected to be either natural organic matter (NOM) or soluble microbial products (SMPs). A laboratory scale reactor was fed chloraminated reverse osmosis (RO) treated water to eliminate the interference from NOM. Once nitrification had set in, experiments were conducted on the reactor and feed waters to determine the identity of the component. The study showed the presence of SMPs released by microbes in severely nitrified waters. Further experiments proved that the SMPs significantly accelerated chloramine decay, probably through catalytic reaction. Moreover, application of common protein denaturing techniques stopped the reaction implying that the compound responsible was likely to be a protein. This significant finding will pave the way for better control of chloramine in the distribution systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. 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.

  2. 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.

  3. A novel injectable water-soluble amphotericin B-arabinogalactan conjugate.

    Science.gov (United States)

    Falk, R; Domb, A J; Polacheck, I

    1999-08-01

    New, stable, highly water-soluble, nontoxic polysaccharide conjugates of amphotericin B (AmB) are described. AmB was conjugated by a Schiff-base reaction with oxidized arabinogalactan (AG). AG is a highly branched natural polysaccharide with unusual water solubility (70% in water). A high yield of active AmB was obtained with the conjugates which were similarly highly water soluble and which could be appropriately formulated for injection. They showed comparable MICs for Candida albicans and Cryptococcus neoformans (MICs, 0.1 to 0.2 microg/ml). The reduced AmB conjugate, which was synthesized at pH 11 for 48 h at 37 degrees C, was nonhemolytic and was much safer than conventional micellar AmB-deoxycholate. It was the least toxic AmB-AG conjugate among those tested with mice (maximal tolerated dose, 50 mg/kg of body weight), and histopathology indicated no damage to the liver or kidneys. This conjugate, similarly to the liposomal formulation (AmBisome), was more effective than AmB-deoxycholate in prolonging survival. It was more effective than both the liposomal and the deoxycholate formulations in eradicating yeast cells from target organs. The overall results suggest that after further development of the AmB-AG conjugate, it may be a potent agent in the treatment of fungal infections.

  4. 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

  5. Assembly of water-soluble chlorophyll-binding proteins with native hydrophobic chlorophylls in water-in-oil emulsions.

    Science.gov (United States)

    Bednarczyk, Dominika; Takahashi, Shigekazu; Satoh, Hiroyuki; Noy, Dror

    2015-03-01

    The challenges involved in studying cofactor binding and assembly, as well as energy- and electron transfer mechanisms in the large and elaborate transmembrane protein complexes of photosynthesis and respiration have prompted considerable interest in constructing simplified model systems based on their water-soluble protein analogs. Such analogs are also promising templates and building blocks for artificial bioinspired energy conversion systems. Yet, development is limited by the challenge of introducing the essential cofactors of natural proteins that are highly water-insoluble into the water-soluble protein analogs. Here we introduce a new efficient method based on water-in-oil emulsions for overcoming this challenge. We demonstrate the effectiveness of the method in the assembly of native chlorophylls with four recombinant variants of the water-soluble chlorophyll-binding protein of Brassicaceae plants. We use the method to gain new insights into the protein-chlorophyll assembly process, and demonstrate its potential as a fast screening system for developing novel chlorophyll-protein complexes.

  6. Immunomodulatory effect of water soluble extract separated from mycelium of Phellinus linteus on experimental atopic dermatitis

    Directory of Open Access Journals (Sweden)

    Hwang Ji

    2012-09-01

    Full Text Available Abstract Background Complementary and alternative medicine (CAM is becoming a popular treatment for modulating diverse immune disorders. Phellinus linteus (P. linteus as one of the CAMs has been used to modulate cancers, inflammation and allergic activities. However, little evidence has been shown about its underlying mechanism of action by which it exerts a beneficial role in dermatological disease in vivo. In this study, we examined the immunomodulatory effects of P. linteus on experimental atopic dermatitis (AD and elucidated its action mechanism. Methods The immunomodulatory effect of total extract of P. linteus on IgE production by human myeloma U266B1 cells was measured by ELISA. To further identify the effective components, P. linteus was fractionated into methanol soluble, water soluble and boiling water soluble extracts. Each extract was treated to U266B1 cells and primary B cells to compare their inhibitory effects on IgE secretion. To test the in vivo efficacy, experimental atopic dermatitis (AD was established by alternative treatment of DNCB and house dust mite extract into BALB/c mice. Water soluble extract of P. linteus (WA or ceramide as a positive control were topically applied to ears of atopic mouse every day for 2 weeks and progression of the disease was estimated by the following criteria: (a ear thickness, clinical score, (b serum total IgE, IgG and mite specific IgE level by ELSIA, (c histological examination of ear tissue by H&E staining and (d cytokine profile of total ear cells and CD4+ T cells by real time PCR and ELSIA. Results Treatment of total extracts of P. linteus to U266B1 inhibited IgE secretion. Among the diverse extracts of P. linteus, water soluble extract of P. linteus (WA significantly reduced the IgE production in primary B cells and B cell line U266B1. Moreover, treatment of WA reduced AD symptoms such as ear swelling, erythema, and dryness and decreased recruitment of lymphocyte into the inflamed site

  7. Cytotoxicity and photocytotoxicity of structure-defined water-soluble C{sub 60}/micelle supramolecular nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Metanawin, Tanapak; Tang Tian; Chen Rongjun; Wang Xiaosong [School of Chemistry, University of Leeds, LS2 9TJ (United Kingdom); Vernon, David, E-mail: X.S.Wang@leeds.ac.uk [School of Biological Sciences, University of Leeds, LS2 9TJ (United Kingdom)

    2011-06-10

    Well-defined, water-soluble C{sub 60}/micelle hierarchical colloids with varied amounts of C{sub 60} sitting on the surface of micellar cores were prepared via the self-assembly of PS-b-PDMA block copolymer micelles and C{sub 60}. The composites can generate a significant amount of reactive oxygen upon irradiation with red light. Cell studies showed that the colloids were either strongly associated with, or internalized by, the cells after 2 h incubation, but did not show obvious toxicity in the dark. In contrast, efficient cell killing was observed when the colloid-incubated cells were exposed to red light. This indicates that the supramolecular colloids are promising as photosensitizers for photodynamic cancer therapy.

  8. Rapid screening of water soluble arsenic species in edible oils using dispersive liquid-liquid microextraction.

    Science.gov (United States)

    López-García, Ignacio; Briceño, Marisol; Vicente-Martínez, Yesica; Hernández-Córdoba, Manuel

    2015-01-15

    A methodology for the non-chromatographic screening of the main arsenic species present in edible oils is discussed. Reverse dispersive liquid-liquid microextraction was used to extract water soluble arsenic compounds (inorganic arsenic, methylarsonate, dimethylarsinate and arsenobetaine) from the edible oils into a slightly acidic aqueous medium. The total arsenic content was measured in the extracts by electrothermal atomic absorption spectrometry using palladium as the chemical modifier. By repeating the measurement using cerium instead of palladium, the sum of inorganic arsenic and methylarsonate was obtained. The detection limit was 0.03 ng As per gram of oil. Data for the total and water-soluble arsenic levels of 29 samples of different origin are presented. Inorganic arsenic was not found in any of the samples marketed as edible oils.

  9. Phosphated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds

    Directory of Open Access Journals (Sweden)

    Cira Mollings Puentes

    2017-01-01

    Full Text Available The utility of phosphated α-, β- and γ-cyclodextrins as water-soluble chiral NMR solvating agents for cationic substrates is described. Two sets of phosphated cyclodextrins, one with degrees of substitution in the 2–6 range, the other with degrees of substitution in the 6–10 range, are examined. Results with 33 water-soluble cationic substrates are reported. We also explored the possibility that the addition of paramagnetic lanthanide ions such as praseodymium(III and ytterbium(III further enhances the enantiomeric differentiation in the NMR spectra. The chiral differentiation with the phosphated cyclodextrins is compared to prior results obtained with anionic carboxymethylated cyclodextrins. There are a number of examples where a larger differentiation is observed with the phosphated cyclodextrins.

  10. Phosphated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds

    Science.gov (United States)

    Puentes, Cira Mollings

    2017-01-01

    Summary The utility of phosphated α-, β- and γ-cyclodextrins as water-soluble chiral NMR solvating agents for cationic substrates is described. Two sets of phosphated cyclodextrins, one with degrees of substitution in the 2–6 range, the other with degrees of substitution in the 6–10 range, are examined. Results with 33 water-soluble cationic substrates are reported. We also explored the possibility that the addition of paramagnetic lanthanide ions such as praseodymium(III) and ytterbium(III) further enhances the enantiomeric differentiation in the NMR spectra. The chiral differentiation with the phosphated cyclodextrins is compared to prior results obtained with anionic carboxymethylated cyclodextrins. There are a number of examples where a larger differentiation is observed with the phosphated cyclodextrins.

  11. 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

  12. 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.

  13. Chemical composition, properties, and antimicrobial activity of the water-soluble pigments from Castanea mollissima shells.

    Science.gov (United States)

    You, Ting-Ting; Zhou, Su-Kun; Wen, Jia-Long; Ma, Chao; Xu, Feng

    2014-02-26

    Agricultural residues Castanea mollissima shells represent a promising resource for natural pigments for the food industry. This study provides a comprehensive and systematic evaluation of water-soluble pigments (CSP) from C. mollissima shells, which were obtained by 50% ethanol with microwave-assisted extraction. Spectroscopic techniques (UV, FT-IR, (13)C NMR), elemental analysis, and chromatographic techniques (HPAEC, GPC) revealed that the main components in the CSP were flavonoids procyanidin B3 (condensed tannin), quercetin-3-O-glycoside, and steroidal sapogenins. As a consequence, CSP was water-soluble and presented significant DPPH scavenge capacity (EC50 value was 0.057 mg/mL). Specially, CSP gave excellent antibacterial activity, and even better than 5% aqueous phenol in some case. Moreover, CSP was practically nontoxic and exhibited good stability with temperature, natural light, and metal ions. These outstanding properties will enlarge the application of CSP for natural food additives production.

  14. The effect of water on the mechanical properties of soluble and insoluble ceramic cements.

    Science.gov (United States)

    Koh, Ilsoo; López, Alejandro; Pinar, Ana B; Helgason, Benedikt; Ferguson, Stephen J

    2015-11-01

    Ceramic cements are good candidates for the stabilization of fractured bone due to their potential ease of application and biological advantages. New formulations of ceramic cements have been tested for their mechanical properties, including strength, stiffness, toughness and durability. The changes in the mechanical properties of a soluble cement (calcium sulfate) upon water-saturation (saturation) was reported in our previous study, highlighting the need to test ceramic cements using saturated samples. It is not clear if the changes in the mechanical properties of ceramic cements are exclusive to soluble cements. Therefore the aim of the present study was to observe the changes in the mechanical properties of soluble and insoluble ceramic cements upon saturation. A cement with high solubility (calcium sulfate dihydrate, CSD) and a cement with low solubility (dicalcium phosphate dihydrate, DCPD) were tested. Three-point bending tests were performed on four different groups of: saturated CSD, non-saturated CSD, saturated DCPD, and non-saturated DCPD samples. X-ray diffraction analysis and scanning electron microscopy were also performed on a sample from each group. Flexural strength, effective flexural modulus and flexural strain at maximum stress, lattice volume, and crystal sizes and shape were compared, independently, between saturated and non-saturated groups of CSD and DCPD. Although material dissolution did not occur in all cases, all calculated mechanical properties decreased significantly in both CSD and DCPD upon saturation. The results indicate that the reductions in the mechanical properties of saturated ceramic cements are not dependent on the solubility of a ceramic cement. The outcome raised the importance of testing any implantable ceramic cements in saturated condition to estimate its in vivo mechanical properties.

  15. Nanostructured liquid crystalline particles provide long duration sustained-release effect for a poorly water soluble drug after oral administration.

    Science.gov (United States)

    Nguyen, Tri-Hung; Hanley, Tracey; Porter, Christopher J H; Boyd, Ben J

    2011-07-30

    This study is the first to demonstrate the ability of nanostructured liquid crystal particles to sustain the absorption of a poorly water soluble drug after oral administration. Cubic (V(2)) liquid crystalline nanostructured particles (cubosomes) formed from phytantriol (PHY) were shown to sustain the absorption of cinnarizine (CZ) beyond 48h after oral administration to rats. Plasma concentrations were sustained within the range of 21.5±1.5ng/mL from 12 to 48h. In stark contrast, cubosomes prepared using glyceryl monooleate (GMO) did not sustain the absorption of CZ and drug concentrations fell below quantifiable levels after 24h. Sustained absorption of CZ from PHY cubosomes lead to a significant enhancement (pnanostructured particles in simulated gastric and intestinal fluids using small angle x-ray scattering (SAXS) revealed that the V(2)Pn3m nanostructure of PHY cubosomes was maintained for extended periods of time, in contrast to GMO cubosomes where the V(2)Im3m nanostructure was lost within 18h after exposure, suggesting that degradation of the LC nanostructure may limit sustained drug release. In addition, PHY cubosomes were shown to be extensively retained in the stomach (>24h) leading to the conclusion that in the case of non-digestible PHY cubosomes, the stomach may act as a non-sink reservoir that facilitates the slow release of poorly water soluble drugs, highlighting the potential use of non-digestible LC nanostructured particles as novel sustained oral drug delivery systems. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Recrystallization of water in non-water-soluble (meth)acrylate polymers is not rare and is not devitrification.

    Science.gov (United States)

    Gemmei-Ide, Makoto; Ohya, Atsushi; Kitano, Hiromi

    2012-02-16

    Change in the state of water sorbed into four kinds of non-water-soluble poly(meth)acrylates with low water content by temperature (T) perturbation was examined on the basis of T variable mid-infrared (MIR) spectroscopy. Many studies using differential scanning calorimetry suggested that there was no change in the state. T dependence of their MIR spectra, however, clearly demonstrated various changes in the state. Furthermore, recrystallization, which was crystallization during heating, was observed in all four polymers. The recrystallization observed in this study was not devitrification, which is the change in the state from glassy water to crystalline water, but vapor deposition during heating (vapor re-deposition). There were only two reports about recrystallization of water in a non-water-soluble polymer before this report; therefore, it might be considered to be a rare phenomenon. However, as demonstrated in this study, it is not a rare phenomenon. Recrystallization (vapor re-deposition) of water in the polymer matrices is related to a balance between flexibility and strength of the electrostatic interaction sites of polymer matrices but might not be related to the biocompatibility of polymers.

  17. 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.

  18. 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...... or deficiency. An impaired absorptive function occurs in a variety of conditions including congenital defects in the digestive or absorptive processes, intestinal diseases, drug interaction, and chronic alcohol use....

  19. Water-soluble phenylpropanoid constituents from aerial roots of Ficus microcarpa.

    Science.gov (United States)

    Ouyang, Ming-An; Chen, Pei-Qing; Wang, Si-Bing

    2007-07-20

    New water-soluble phenylpropanoid constituents, ficuscarpanoside A, guaiacylglycerol 9-O-beta-D-glucopyranoside, and erythro-guaiacylglycerol 9-O-beta-D-glucopyranoside, along with known guaiacylglycerol, erythro-guaiacylglycerol, 4-methoxy guaiacylglycerol 7-O-beta-D-glucopyranoside, and 3-(4-hydroxy-3-methoxy phenyl) propan-1,2-diol, have been isolated from the aerial roots of Ficus microcarpa. Their structures were elucidated on the basis of 1D and 2D NMR experiments.

  20. Automatic Carbon Dioxide-Methane Gas Sensor Based on the Solubility of Gases in Water

    OpenAIRE

    Cadena-Pereda, Raúl O.; Anaya-Rivera, Ely K.; Gilberto Herrera-Ruiz; Eric M. Rivera-Muñoz; Gomez-Melendez, Domingo J.

    2012-01-01

    Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such a...

  1. 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.

  2. Selecting water-alcohol mixed solvent for synthesis of polydopamine nano-spheres using solubility parameter

    OpenAIRE

    Jiang, Xiaoli; Wang, Yinling; Li, Maoguo

    2014-01-01

    The solvent plays an important role in a given chemical reaction. Since most reaction in nature occur in the mixed-solvent systems, a comprehensive principle for solvent optimization was required. By calculating the Hansen solubility parameters (HSP) distance Ra , we designed a model experiment to explore the influence of mixed solvents on the chemical synthesis. The synthesis of polydopamine (PDA) in the water-alcohol system was chosen as model. As predicted, the well-dispersed PDA spheres w...

  3. 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 olefin...... PEI-PNH as ligands show lower stability and activity in both SAPC and biphasic applications....

  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. Structural features of a water soluble gum polysaccharide from Murraya paniculata fruits.

    Science.gov (United States)

    Mondal, S K; Ray, B; Ghosal, P K; Teleman, A; Vuorinen, T

    2001-10-22

    A water soluble gum polysaccharide was isolated from Murraya paniculata fruits. Hydrolytic experiments, methylation analysis, periodate oxidation studies and NMR data revealed that the polysaccharide was extensively branched and it consisted of 1,3-, and 1,3,6-linked beta-D-galactopyranosyl units, terminal beta-D-galactopyranosyl units and terminal alpha-D-glucopyranosyl 1,4-beta-D-galactopyranosyl units. Small amounts of 4-O-methylglucuronic acid residues were also present.

  6. NASA Workmanship Hot Topics: Water Soluble Flux and ESD Charge Device Model

    Science.gov (United States)

    Plante, Jeannette F.

    2009-01-01

    This slide presentation reviews two topics of interest to NASA Workmanship: (1) Water Soluble Flux (WSF) and Electrostatic Discharge (ESD) safety. In the first topic, WSF, the presentation reviews voiding and the importance of cleanliness in using WSF for welding and soldering operations. The second topic reviews the NASA-HDBK-8739.21 for Human Body Model, and Machine Model safety methods, and challenges associated with the Charged Device Model (CDM)

  7. Solubility and thermodynamic behavior of vanillin in propane-1,2-diol+water cosolvent mixtures at different temperatures.

    Science.gov (United States)

    Shakeel, Faiyaz; Haq, Nazrul; Siddiqui, Nasir A; Alanazi, Fars K; Alsarra, Ibrahim A

    2015-12-01

    The solubilities of bioactive compound vanillin were measured in various propane-1,2-diol+water cosolvent mixtures at T=(298-318)K and p=0.1 MPa. The experimental solubility of crystalline vanillin was determined and correlated with calculated solubility. The results showed good correlation of experimental solubilities of crystalline vanillin with calculated ones. The mole fraction solubility of crystalline vanillin was recorded highest in pure propane-1,2-diol (7.06×10(-2) at 298 K) and lowest in pure water (1.25×10(-3) at 298 K) over the entire temperature range investigated. Thermodynamic behavior of vanillin in various propane-1,2-diol+water cosolvent mixtures was evaluated by Van't Hoff and Krug analysis. The results showed an endothermic, spontaneous and an entropy-driven dissolution of crystalline vanillin in all propane-1,2-diol+water cosolvent mixtures. Based on solubility data of this work, vanillin has been considered as soluble in water and freely soluble in propane-1,2-diol.

  8. 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.

  9. Encapsulation of poorly water-soluble drugs into organic nanotubes for improving drug dissolution.

    Science.gov (United States)

    Moribe, Kunikazu; Makishima, Takashi; Higashi, Kenjirou; Liu, Nan; Limwikrant, Waree; Ding, Wuxiao; Masuda, Mitsutoshi; Shimizu, Toshimi; Yamamoto, Keiji

    2014-07-20

    Hydrocortisone (HC), a poorly water-soluble drug, was encapsulated within organic nanotubes (ONTs), which were formed via the self-assembly of N-{12-[(2-α,β-d-glucopyranosyl) carbamoyl]dodecanyl}-glycylglycylglycine acid. The stability of the ONTs was evaluated in ten organic solvents, of differing polarities, by field emission transmission electron microscopy. The ONTs maintained their stable tubular structure in the highly polar solvents, such as ethanol and acetone. Furthermore, solution-state (1)H-NMR spectroscopy confirmed that they were practically insoluble in acetone at 25°C (0.015 mg/mL). HC-loaded ONTs were prepared by solvent evaporation using acetone. A sample with a 3/7 weight ratio of HC/ONT was analyzed by powder X-ray diffraction, which confirmed the presence of a halo pattern and the absence of any crystalline HC peak. HC peak broadening, observed by solid-state (13)C-NMR measurements of the evaporated sample, indicated the absence of HC crystals. These results indicated that HC was successfully encapsulated in ONT as an amorphous state. Improvements of the HC dissolution rate were clearly observed in aqueous media at both pH 1.2 and 6.8, probably due to HC amorphization in the ONTs. Phenytoin, another poorly water-soluble drug, also showed significant dissolution improvement upon ONT encapsulation. Therefore, ONTs can serve as an alternative pharmaceutical excipient to enhance the bioavailability of poorly water-soluble drugs.

  10. Seasonal variations of concentrations and optical properties of water soluble HULIS collected in urban environments

    Directory of Open Access Journals (Sweden)

    C. Baduel

    2010-05-01

    Full Text Available Major contributors to the organic aerosol include water-soluble macromolecular compounds (e.g. HULISWS: Water Soluble Humic LIke Substances. The nature and sources of HULISWS are still largely unknown. This work is based on a monitoring in six different French cities performed during summer and winter seasons. HULISWS analysis was performed with a selective method of extraction complemented by carbon quantification. UV spectroscopy was also applied for their chemical characterisation. HULISWS carbon represent an important contribution to the organic aerosol mass in summer and winter, as it accounts for 12–22% of Organic Carbon and 34–40% of Water Soluble Organic Carbon. We found strong differences in the optical properties (specific absorbance at 250, 272, 280 nm and E2/E3 ratio and therefore in the chemical structure between HULISWS from samples of summer- and wintertime. These differences highlight different processes responsible for emissions and formation of HULISWS according to the season, namely biomass burning in winter, and secondary processes in summer. Specific absorbance can also be considered as a rapid and useful indicator of the origin of HULISWS in urban environment.

  11. A predictive model for the release of slightly water-soluble drugs from HPMC matrices.

    Science.gov (United States)

    Fu, X C; Wang, G P; Wang, Y H; Liang, W Q

    2004-08-01

    A model to predict the fraction of slightly water-soluble drug released as a function of release time (t, h), HPMC concentration (C(H), w/w), drug solubility in distilled water at 37 degrees C (C(s), g/100 mL), and volume of drug molecule (V, nm3) was derived when theophyline, tinidazole, and propylthiouracil were selected as model drugs. The model is log (M(t)/M(infinity)) = 0.8683 logt-0.1930C(s) logt + 0.5406V logt-1.227C(H) + 0.1594C(s) + 0.4423C(H)C(s) - 0.8655 (n = 130, r = 0.9969), where Mt is the amount of drug released at time t, Minfinity is the amount of drug released over a very long time, which corresponds in principle to the initial loading, n is the number of samples, and r is the correlation coefficient. The model was validated using sulfamethoxazole and satisfactory results were obtained. The model can be used to predict the release fraction of variousslightly water-soluble drugs from HPMC matrices having different polymer levels.

  12. Nanosizing of poorly water soluble compounds using rotation/revolution mixer.

    Science.gov (United States)

    Takatsuka, Takayuki; Endo, Tomoko; Jianguo, Yao; Yuminoki, Kayo; Hashimoto, Naofumi

    2009-10-01

    In this study, nanoparticles of various poorly water soluble compounds were prepared by wet milling that was carried out using a rotation/revolution mixer and zirconia balls. To be compared with Beads mill, rotation/revolution mixer has superior in very quick process (5 min) and needs very few amounts of zirconia balls (2.4 g) for pulverizing drugs to nanometer range. Phenytoin, indomethacin, nifedipine, danazol, and naproxen were selected as the standard poorly water soluble compounds. Various parameters of the rotation/revolution mixer were studied to decide the optimal pulverization conditions for the production of nanoparticles of the abovementioned compounds. The rotation/revolution speed, shape of the mixing vessel, amount of zirconia balls, and volume of the vehicle (methylcellulose solution) mainly affected the pulverization of the compounds. Using the mixer, phenytoin could be pulverized to nanoparticles within a few minutes. The particle size was confirmed by using a scanning electron microscope and a particle size analyzer. The crystallinity of the pulverized phenytoin particles was confirmed by X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). It was observed that the pulverized phenytoin particles retained their crystallinity, and amorphous phenytoin was not detected. Particles of other poorly water soluble compounds were also reduced to the nanometer range by using this method.

  13. Poly(ether ester) Ionomers as Water-Soluble Polymers for Material Extrusion Additive Manufacturing Processes.

    Science.gov (United States)

    Pekkanen, Allison M; Zawaski, Callie; Stevenson, André T; Dickerman, Ross; Whittington, Abby R; Williams, Christopher B; Long, Timothy E

    2017-04-12

    Water-soluble polymers as sacrificial supports for additive manufacturing (AM) facilitate complex features in printed objects. Few water-soluble polymers beyond poly(vinyl alcohol) enable material extrusion AM. In this work, charged poly(ether ester)s with tailored rheological and mechanical properties serve as novel materials for extrusion-based AM at low temperatures. Melt transesterification of poly(ethylene glycol) (PEG, 8k) and dimethyl 5-sulfoisophthalate afforded poly(ether ester)s of sufficient molecular weight to impart mechanical integrity. Quantitative ion exchange provided a library of poly(ether ester)s with varying counterions, including both monovalent and divalent cations. Dynamic mechanical and tensile analysis revealed an insignificant difference in mechanical properties for these polymers below the melting temperature, suggesting an insignificant change in final part properties. Rheological analysis, however, revealed the advantageous effect of divalent countercations (Ca(2+), Mg(2+), and Zn(2+)) in the melt state and exhibited an increase in viscosity of two orders of magnitude. Furthermore, time-temperature superposition identified an elevation in modulus, melt viscosity, and flow activation energy, suggesting intramolecular interactions between polymer chains and a higher apparent molecular weight. In particular, extrusion of poly(PEG8k-co-CaSIP) revealed vast opportunities for extrusion AM of well-defined parts. The unique melt rheological properties highlighted these poly(ether ester) ionomers as ideal candidates for low-temperature material extrusion additive manufacturing of water-soluble parts.

  14. Water-Soluble Coenzyme Q10 Reduces Rotenone-Induced Mitochondrial Fission.

    Science.gov (United States)

    Li, Hai-Ning; Zimmerman, Mary; Milledge, Gaolin Z; Hou, Xiao-Lin; Cheng, Jiang; Wang, Zhen-Hai; Li, P Andy

    2017-02-11

    Parkinson's disease is a neurodegenerative disorder characterized by mitochondrial dysfunction and oxidative stress. It is usually accompanied by an imbalance in mitochondrial dynamics and changes in mitochondrial morphology that are associated with impaired function. The objectives of this study were to identify the effects of rotenone, a drug known to mimic the pathophysiology of Parkinson's disease, on mitochondrial dynamics. Additionally, this study explored the protective effects of water-soluble Coenzyme Q10 (CoQ10) against rotenone-induced cytotoxicity in murine neuronal HT22 cells. Our results demonstrate that rotenone elevates protein expression of mitochondrial fission markers, Drp1 and Fis1, and causes an increase in mitochondrial fragmentation as evidenced through mitochondrial staining and morphological analysis. Water-soluble CoQ10 prevented mitochondrial dynamic imbalance by reducing Drp1 and Fis1 protein expression to pre-rotenone levels, as well as reducing rotenone treatment-associated mitochondrial fragmentation. Hence, water-soluble CoQ10 may have therapeutic potential in treating patients with Parkinson's disease.

  15. Laboratory investigation of aluminum solubility and solid-phase properties following alum treatment of lake waters.

    Science.gov (United States)

    Berkowitz, Jacob; Anderson, Michael A; Graham, Robert C

    2005-10-01

    Water samples from two southern California lakes adversely affected by internal nutrient loading were treated with a 20 mg/L dose of Al3+ in laboratory studies to examine Al solubility and solid-phase speciation over time. Alum [Al2(SO4)3 . 18 H2O] applications to water samples from Big Bear Lake and Lake Elsinore resulted in a rapid initial decrease in pH and alkalinity followed by a gradual recovery in pH over several weeks. Dissolved Al concentrations increased following treatment, reaching a maximum of 2.54 mg/L after 17 days in Lake Elsinore water and 0.91 mg/L after 48 days in Big Bear Lake water; concentrations in both waters then decreased to Lake Elsinore water. Surface areas also decreased over time as crystals reordered to form gibbsite/microcrystalline gibbsite species. DSC-TGA results suggested that the initially formed amorphous Al(OH)3 underwent transformation to >45% gibbsite. These results were supported by geochemical modeling using Visual MINTEQ, with Al solubility putatively controlled by amorphous Al(OH)3 shortly after treatment and approaching that of microcrystalline gibbsite after about 150 days. These findings indicate that Al(OH)3 formed after alum treatment undergoes significant chemical and mineralogical changes that may alter its effectiveness as a reactive barrier to phosphorus release from lake sediments.

  16. Sensitive detection of mercury (II) ion using water-soluble captopril-stabilized fluorescent gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Jiu-Ju; Huang, Hong; Chen, Wei-Jie; Chen, Jian-Rong; Lin, Hong-Jun; Wang, Ai-Jun, E-mail: ajwang@zjnu.cn

    2013-07-01

    In our work, a simple, facile, and green method was developed for the synthesis of water-soluble and well-dispersed fluorescent gold nanoparticles (Au NPs) within 5 min, using captopril as a capping agent. The as-prepared Au NPs showed strong emission at 414 nm, with a quantum yield of 5.5%. The fluorescence of the Au NPs can be strongly quenched by mercury (II) ion (Hg{sup 2+}) due to the stronger interactions between thiolates (RS{sup −}) and Hg{sup 2+}. It was applied to the detection of Hg{sup 2+} in water samples in the linear ranges of 0.033–0.133 μM and 0.167–2.500 μM, with a detection limit of 0.017 μM. Therefore, the as-prepared Au NPs can meet the requirement for monitoring Hg{sup 2+} in environmental samples. - Graphical abstract: In this work, we developed a simple, fast and facile method for the preparation of water-soluble and fluorescent gold nanoparticles (Au NPs). The trace existence of Hg{sup 2+} could strongly quench the fluorescence of the Au NPs. The Au NPs were used to detect highly toxic Hg{sup 2+} in water samples with high sensitivity and selectivity. Highlights: ► Water-soluble fluorescent Au NPs stabilized by captopril ► The synthesis procedure was simple, fast and facile. ► The fluorescence of the Au NPs can be strongly quenched by Hg{sup 2+}. ► The Au NPs were used to the assay of Hg{sup 2+} in water samples with high sensitivity and selectivity.

  17. Antioxidant effects of the water-soluble fraction of baked sponge cake made with silky fowl egg: comparison with White Leghorn egg.

    Science.gov (United States)

    Toyosaki, T; Koketsu, M

    2007-08-01

    1. The antioxidant effects of the water-soluble fraction of baked sponge cakes made with silky fowl eggs and White Leghorn eggs were studied. The mechanism of the antioxidant effect was also investigated. 2. The antioxidant effect on the oxidation of linoleic acid increased in the water-soluble fraction of cake made with silky eggs. In contrast, Leghorn eggs significantly decreased the rate of antioxidant activity. The browning index of the water-soluble fraction of baked sponge cake made with silky fowl eggs changed from 0.052 to 1.240 after 20 min at 180 degrees C, while that made with Leghorn eggs changed from 0.037 to 0.710. 3. There are correlations between the rate of browning index and antioxidant activity. Superoxide anion (O2(-)) and hydrogen peroxide (H(2)O(2)) in water-soluble fractions of baked sponge cakes made with silky fowl eggs and hen's eggs were formed during light exposure for 20 min at 10,000 lux, and their formation could be significantly inhibited by the addition of tryptophan or mannitol, scavengers of hydroxyl radicals (*OH). These results were strong evidence of direct participation of *OH, formed by the Haber-Weiss reaction, in the water-soluble fraction of baked sponge cakes. The rate of decrease in active oxygen by scavengers decreased in Leghorn eggs more efficiently than in silky eggs. 4. The present experiments suggested that the use of silky fowl eggs could improve the quality and oxidative stability of baked cakes.

  18. Water-soluble chelating polymers for removal of actinides from watewater

    Energy Technology Data Exchange (ETDEWEB)

    Jarvinen, G. [Los Alamos National Lab., NM (United States)

    1996-10-01

    Polymer filtration is a technology being developed to recover valuable or regulated metal ions selectively from process or wastewaters. Water-soluble chelating polymers are specially designed to bind selectively with metal ions in aqueous solutions. The polymers molecular weight is large enough so they can be separated and concentrated using available ultrafiltration technology. Water and smaller unbound components of the solution pass freely through the ultrafiltration membrane. The polymers can then be reused by changing the solution conditions to release the metal ions, which are recovered in concentrated form, for recycle or disposal.

  19. 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.

  20. Water soluble decontamination coating for Defense Waste Processing Facility (DWPF) canisters

    Energy Technology Data Exchange (ETDEWEB)

    Selby, C.L.

    1986-12-17

    Water soluble sodium borate glass coating was successfully codeveloped by Clemson University (Dr. H.G. Lefort) and Du Pont as an alternative decontamination process to frit slurry blasting of Defense Waste Processing Facility (DWPF) canisters. Slurry blasting requires transport of abrasive slurries, might cause galling by entrapped frit particles, and could result in frit slurry freezeup in pumps and retention basins. Contamination can be removed from precoated canisters with a gentle hot water rinse. Glass waste spilled on a coated canister will spall off spontaneously during canister cooling. A glass coating appears to prevent transfer of contamination to the Canister Decontamination Cell (CDC) guides and cradle. 1 ref., 5 tabs.

  1. 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.

  2. Mechanistic studies of metal ion binding to water-soluble polymers using potentiometry.

    Science.gov (United States)

    Jarvis, N V; Wagener, J M

    1995-02-01

    A method for elucidating metal ion binding mechanisms with water-soluble polymers has been developed in which the polymer is treated as a collection of monomeric units. Data obtained from potentiometric titrations are analysed by the ESTA library of programs and apparent formation constants may be calculated. From this information, predictions may be made as to metal ion separation using complexation-ultrafiltration techniques. The polymer used in this study was Polymin Water-Free and its complexation with Hg(II), Cd(II), Pb(II), Co(II) and Ni(II) was successfully modelled.

  3. Gelatinization and solubility of corn starch during heating in excess water: new insights.

    Science.gov (United States)

    Ratnayake, Wajira S; Jackson, David S

    2006-05-17

    Starch gelatinization is associated with the disruption of granular structure causing starch molecules to disperse in water. This study was designed to examine starch granules as they were heated in water, and their resulting morphological, structural, and solubility traits. The results indicate that starch gelatinization is a more complex process than the previously suggested order-to-disorder transition. The energy absorbed by the granules facilitates the rearrangement or formation of new bonds among molecules prior to the temperatures normally associated with the melting of amylopectin crystallites during gelatinization. It is also evident that amylose plays an important role during the initial stages of corn starch gelatinization.

  4. Estimating the physicochemical properties of polyhalogenated aromatic and aliphatic compounds using UPPER: part 2. Aqueous solubility, octanol solubility and octanol-water partition coefficient.

    Science.gov (United States)

    Admire, Brittany; Lian, Bo; Yalkowsky, Samuel H

    2015-01-01

    The UPPER (Unified Physicochemical Property Estimation Relationships) model uses additive and non-additive parameters to estimate 20 biologically relevant properties of organic compounds. The model has been validated by Lian and Yalkowsky (2014) on a data set of 700 hydrocarbons. Recently, Admire et al. (2014) expanded the model to predict the boiling and melting points of 1288 polyhalogenated benzenes, biphenyls, dibenzo-p-dioxins, diphenyl ethers, anisoles and alkanes. In this work, 19 new group descriptors are determined and used to predict the aqueous solubilities, octanol solubilities and the octanol-water coefficients.

  5. 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.

  6. Modeling phase distribution of water-soluble organics in aqueous solutions using surface tension data

    Science.gov (United States)

    Cline, B.; Hiatt, J.; Aumann, E.; Cabrera, J.; Tabazadeh, A.

    2006-12-01

    A good fraction (greater than 30 percent) of submicron particle mass in the atmosphere is often composed of water-soluble organic carbon. Identifiable, water-miscible organics, such as, known sugars, small alcohols, small diacids, etc. comprise only a small fraction of the water-soluble mass (about 1-2 percent). Most of the water-soluble mass is often composed of unidentifiable, humic-like materials, which are commonly refereed to as HULIS. Humic substances are known to form colloids in aqueous solutions at very low aqueous concentrations. Thus, it is likely for HULIS to also be colloid-forming in aqueous solutions. Here, we present surface tension measurements of water-miscible and colloid-forming organics, using methanol and sodium laurate as analogs, respectively. By relating the change in surface tension to chemical potential of the solution, we determine a relationship between surface tension and the surface excess of solute; that is, the number of molecules of solute adsorbed at the surface. Assuming surface acts as a monolayer, we model the adsorption with a Langmuir isotherm to extract the surface excess as a function of solute mole fraction. This relationship allows us to calculate the solute's distribution between bulk and surface phases for methanol, and in bulk, surface and colloid phases for sodium laurate. A colloid of sodium laurate contains approximately 100 laurate anions in a spherical cluster. We present adsorption constants for methanol and sodium laurate (derived from our surface tension data), critical micelle concentration for sodium laurate (derived from our surface tension data), and all the other thermocehmical constants (obtained from the literature) required to constrain a model for determining phase partitioning of organics in aqueous solutions.

  7. Water-soluble carbohydrates and fructan structure patterns from Agave and Dasylirion species.

    Science.gov (United States)

    Mancilla-Margalli, N Alejandra; López, Mercedes G

    2006-10-04

    Fructans, storage carbohydrates with beta-fructofuranosyl linkages, are found in approximately 15% of higher plants. The metabolic flexibility of those molecules allows them easily to polymerize and depolymerize to soluble carbohydrates according to plant development stage and environmental conditions. In this work, water-soluble carbohydrates, including fructan structure patterns, were compared among Agave and Dasylirion species grown in different environmental regions in Mexico. Fructans were the main storage carbohydrate present in Agave stems, in addition to other carbohydrates related to its metabolism, whereas Dasylirion spp. presented a different carbohydrate distribution. A good correlation of water-soluble carbohydrate content with climatic conditions was observed. Fructans in Agave and Dasylirion genera were found in the form of polydisperse molecules, where structural heterogeneity in the same plant was evidenced by methylation linkage analysis and chromatographic methods. Fructans from the studied species were classified into three groups depending on DP and linkage-type abundance. These storage carbohydrates share structural characteristics with fructans in plants that belong to the Asparagales members. Agave and Dasylirion fructans can be categorized as graminans and branched neo-fructans, which we have termed agavins.

  8. Selecting water-alcohol mixed solvent for synthesis of polydopamine nano-spheres using solubility parameter

    Science.gov (United States)

    Jiang, Xiaoli; Wang, Yinling; Li, Maoguo

    2014-08-01

    The solvent plays an important role in a given chemical reaction. Since most reaction in nature occur in the mixed-solvent systems, a comprehensive principle for solvent optimization was required. By calculating the Hansen solubility parameters (HSP) distance Ra, we designed a model experiment to explore the influence of mixed solvents on the chemical synthesis. The synthesis of polydopamine (PDA) in the water-alcohol system was chosen as model. As predicted, the well-dispersed PDA spheres were obtained in selected solvents with smaller Ra values: methanol/water, ethanol/water and 2-propanol/water. In addition, the mixed solvent with smaller Ra values gave a higher conversion of dopamine. The strategy for mixed solvent selection is might be useful to choose optimal reaction media for efficient chemical synthesis.

  9. Selecting water-alcohol mixed solvent for synthesis of polydopamine nano-spheres using solubility parameter

    Science.gov (United States)

    Jiang, Xiaoli; Wang, Yinling; Li, Maoguo

    2014-01-01

    The solvent plays an important role in a given chemical reaction. Since most reaction in nature occur in the mixed-solvent systems, a comprehensive principle for solvent optimization was required. By calculating the Hansen solubility parameters (HSP) distance Ra, we designed a model experiment to explore the influence of mixed solvents on the chemical synthesis. The synthesis of polydopamine (PDA) in the water-alcohol system was chosen as model. As predicted, the well-dispersed PDA spheres were obtained in selected solvents with smaller Ra values: methanol/water, ethanol/water and 2-propanol/water. In addition, the mixed solvent with smaller Ravalues gave a higher conversion of dopamine. The strategy for mixed solvent selection is might be useful to choose optimal reaction media for efficient chemical synthesis. PMID:25317902

  10. Dissolution Enhancement of Poorly Water Soluble Efavirenz by Hot Melt Extrusion Technique

    Directory of Open Access Journals (Sweden)

    Smita Kolhe

    2013-06-01

    studies also showed enhancement in release rate of HME complex. Stability studies at 40 º C/75 % RH (relative humidity were studied and it shows that the sample is stable even after 3 months study. HME is simple and efficient method to improve dissolution and permeability of poorly water soluble Efv.

  11. Formulation of poorly water-soluble drugs via coacervation--a pilot study using febantel.

    Science.gov (United States)

    De Jaeghere, W; De Geest, B G; Van Bocxlaer, J; Remon, J P; Vervaet, C; Antunes da Fonseca, A

    2013-11-01

    In this study, febantel was dissolved under increased temperature in a nonionic surfactant Lutrol L44® and subsequently mixed into an aqueous maltodextrin solution. After 8h under static conditions, coacervation or phase separation took place. (1)H NMR spectra and HPLC analysis showed that the upper phase contained mainly all febantel, while no febantel was detected in the lower phase. Fluorescent microscopy showed that maltodextrin is distributed in the lower phase. Coacervation proved to be a promising formulation technology for certain poorly water-soluble drugs, such as febantel. The coacervate phase showed an increase in in vitro dissolution kinetics, compared to Rintal® granules. These results were confirmed in an in vivo study performed on dogs. Febantel and fenbendazole showed a significant increase in plasma concentration compared to Rintal® granules. Further studies have to be performed to transform coacervates into a solid dosage form and to prove broad applicability to other poorly soluble drugs.

  12. A mathematical model to predict the release of water-soluble drugs from HPMC matrices.

    Science.gov (United States)

    Fu, X C; Wang, G P; Fu, C Y; Liang, W Q

    2004-09-01

    A mathematical model to predict the fraction of water-soluble drug released as a function of release time (t, h), HPMC concentration (CH, w/w), and volume of drug molecule (V, nm3) was derived with ranitidine hydrochloride, diltiazem hydrochloride, and ribavirin as model drugs. The model is log (M(t)/M(infinity)) = 0.5 log t-0.3322CH-0.2222V-0.2988 (n = 140, r = 0.9848), where M(t) is the amount of drug released at time t, M(infinity) is the amount of drug released over a very long time, which corresponds in principle to the initial loading, n is the number of samples, and r is the correlation coefficient. The model was validated using isoniazid and satisfactory results were obtained. The model can be used to predict the release fraction of various soluble drugs from HPMC matrices having different polymer levels.

  13. 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...

  14. A new member of the oxygen-photosensitizers family: a water-soluble polymer binding a platinum complex.

    Science.gov (United States)

    Ricciardi, Loredana; Puoci, Francesco; Cirillo, Giuseppe; La Deda, Massimo

    2012-08-28

    The grafting of a 2-picolylamine Pt(II) complex into polymethacrylic acid has been successfully performed. The obtained polymer is water soluble, and it represents the first example of a platinum-containing polymer able to photogenerate singlet oxygen.

  15. The ultrafast reactions in the photochromic cycle of water-soluble fulgimide photoswitches.

    Science.gov (United States)

    Slavov, C; Boumrifak, C; Hammer, C A; Trojanowski, P; Chen, X; Lees, W J; Wachtveitl, J; Braun, M

    2016-04-21

    Photochromic switches are essential for the control and manipulation of nanoscale reactions and processes. The expansion of their application to aqueous environments depends strongly on the development of optimized water-soluble photoswitches. Here we present a femtosecond time-resolved investigation of the photochromic reactions (transition between the open and the closed form) of a water-soluble indolylfulgimide. We observe a pronounced effect of the protic nature of water as a solvent on the ultrafast ring-opening reaction. Typically, the excited state of the closed form has a larger dipole moment than the ground state, which leads to stabilization of the excited state in polar solvents and hence a lifetime (3 ps) longer than in non-polar solvents (2 ps). However, in water, despite the increased solvent polarity and the increased excited state dipole moment, the opposite trend for the excited state lifetime is observed (1.8 ps). This effect is caused by the opening of a new excited state deactivation pathway involving proton transfer reactions.

  16. A general strategy to fabricate ligand-free water-soluble up-conversion nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhihua, E-mail: lizhihua2006@126.com [Department of Chemistry, Shandong Normal University, Jinan 250014 (China); State Key Lab of Crystal Materials, Shandong University, Jinan 250100 (China); Li, Ying; Wang, Yanan; Miao, Haixia; Du, Yu [Department of Chemistry, Shandong Normal University, Jinan 250014 (China); Liu, Hong [State Key Lab of Crystal Materials, Shandong University, Jinan 250100 (China)

    2014-11-15

    Highlights: • We notice that the coordination energy of Y{sup 3+} ions with oleate is less than the normal chemical bond, which can be broken by high power external force. • We report a simple and easily-operated physical method, ultrasonic separation, to remove the oleate ligand from the surface of NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+}. • The oleate removing method can be applied to the converting of many nanomaterials from oil soluble to water soluble. - Abstract: It is a generally accepted method to synthesize the monodisperse NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+} with uniform size and shape by using oleic acid (OA) as surfactant or solvent. However, the obtained oleate-capped up-conversion nanoparticles NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+} (Ln-UCNPs, Ln = Yb{sup 3+}, Er{sup 3+}) have inherent hydrophobia properties, which should be processed by complicated post-treatments to render them water dispersible before used in biomedicine. Herein, we introduce a facile approach, ultrasonic separation, to obtain water-soluble and ligand-free Ln-UCNPs by analyzing the capping effect between Ln{sup 3+} and the carboxy group of oleate anions. After ultrasonic separation, the ligand-free of Ln-UCNPs disperse in water and ethanol easily, which are characterized by transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), thermogravimetric analyses (TGA), nuclear magnetic resonance (NMR) and zeta potential. The experiments demonstrate that the present method is simple and effective to remove oleate layers from the surface of NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+}, and worthy of being generalized.

  17. 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.

  18. Fabrication of magnetic water-soluble hyperbranched polyol functionalized graphene oxide for high-efficiency water remediation

    Science.gov (United States)

    Hu, Lihua; Li, Yan; Zhang, Xuefei; Wang, Yaoguang; Cui, Limei; Wei, Qin; Ma, Hongmin; Yan, Liangguo; Du, Bin

    2016-06-01

    Magnetic water-soluble hyperbranched polyol functionalized graphene oxide nanocomposite (MWHPO-GO) was successfully prepared and applied to water remediation in this paper. MWHPO-GO was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), magnetization curve, zeta potential, scanning electron microscope (SEM) and transmission electron microscope (TEM) analyses. MWHPO-GO exhibited excellent adsorption performance for the removal of synthetic dyes (methylene blue (MB) and methyl violet (MV)) and heavy metal (Pb(II)). Moreover, MWHPO-GO could be simply recovered from water with magnetic separation. The pseudo-second order equation and the Langmuir model exhibited good correlation with the adsorption kinetic and isotherm data, respectively, for these three pollutants. The thermodynamic results (ΔG water remediation.

  19. Metabolic responses to water deficit in two Eucalyptus globulus clones with contrasting drought sensitivity.

    Science.gov (United States)

    Shvaleva, A L; Costa E Silva, F; Breia, E; Jouve, J; Hausman, J F; Almeida, M H; Maroco, J P; Rodrigues, M L; Pereira, J S; Chaves, M M

    2006-02-01

    We compared the metabolic responses of leaves and roots of two Eucalyptus globulus Labill. clones differing in drought sensitivity to a slowly imposed water deficit. Responses measured included changes in concentrations of soluble and insoluble sugars, proline, total protein and several antioxidant enzymes. In addition to the general decrease in growth caused by water deficit, we observed a decrease in osmotic potential when drought stress became severe. In both clones, the decrease was greater in roots than in leaves, consistent with the observed increases in concentrations of soluble sugars and proline in these organs. In roots of both clones, glutathione reductase activity increased significantly in response to water deficit, suggesting that this enzyme plays a protective role in roots during drought stress by catalyzing the catabolism of reactive oxygen species. Clone CN5 has stress avoidance mechanisms that account for its lower sensitivity to drought compared with Clone ST51.

  20. Synthesis and Spectral Properties of Novel Water-soluble Near-infrared Fluorescent Indocyanines

    Institute of Scientific and Technical Information of China (English)

    Li Qiu WANG; Xiao Jun PENG; Wei Bing ZHANG; Fei YIN; Jing Nan CUI; Xin Qin GAO

    2005-01-01

    Two fluorescent pentamethine and a squarylium indocyanines containing at least one p-carboxybenzyl group on N atoms in the heterocyclic rings were synthesized. They had good water solubility and photostability. Their maximum absorption and maximum emission were600-700 nm in water. When it was anchored onto nanostructured TiO2 electrode, compared with in water, the squaraine showed double absorption peaks (one blue shifted and another red shifted)and absorption intensity of the red shift peak increased with the increase of the time of irradiation.The intensity of the blue one decreased simultaneously. We proposed that the presence of two electronic charge forms of squaraine anchored on the TiO2 film might be the reason.

  1. Luminescent, water-soluble silicon quantum dots via micro-plasma surface treatment

    Science.gov (United States)

    Wu, Jeslin J.; Kondeti, Vighneswara Siva Santosh Kumar; Bruggeman, Peter J.; Kortshagen, Uwe R.

    2016-03-01

    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.

  2. A method for separating water soluble organics from a process stream by aqueous biphasic extraction

    Energy Technology Data Exchange (ETDEWEB)

    Chaiko, David J.; Mego, William A.

    1997-12-01

    The present invention relates to a method for separating water-miscible organic species from a process stream by aqueous biphasic extraction. In particular, the method includes extracting the organic species into a polymer-rich phase of an aqueous biphase system in which the process stream comprises the salt-rich phase, and, next, separating the polymer from the extracted organic species by contacting the loaded, polymer-rich phase with a water-immiscible organic phase. Alternatively, the polymer can be separated from the extracted organic species by raising the temperature of the loaded, polymer-rich phase above the cloud point, such that the polymer and the water-soluble organic species separate into two distinct aqueous phases. In either case, a substantially salt-free, concentrated aqueous solution containing the organic species is recovered.

  3. Lipid–Protein Nanodiscs Offer New Perspectives for Structural and Functional Studies of Water-Soluble Membrane-Active Peptides

    Science.gov (United States)

    Shenkarev, Z. O.; Lyukmanova, E. N.; Paramonov, A. S.; Panteleev, P. V.; Balandin, S. V.; Shulepko, M. A.; Mineev, K. S.; Ovchinnikova, T. V.; Kirpichnikov, M. P.; Arseniev, A. S.

    2014-01-01

    Lipid-protein nanodiscs (LPNs) are nanoscaled fragments of a lipid bilayer stabilized in solution by the apolipoprotein or a special membrane scaffold protein (MSP). In this work, the applicability of LPN-based membrane mimetics in the investigation of water-soluble membrane-active peptides was studied. It was shown that a pore-forming antimicrobial peptide arenicin-2 from marine lugworm (charge of +6) disintegrates LPNs containing both zwitterionic phosphatidylcholine (PC) and anionic phosphatidylglycerol (PG) lipids. In contrast, the spider toxin VSTx1 (charge of +3), a modifier of Kv channel gating, effectively binds to the LPNs containing anionic lipids (POPC/DOPG, 3 : 1) and does not cause their disruption. VSTx1 has a lower affinity to LPNs containing zwitterionic lipids (POPC), and it weakly interacts with the protein component of nanodiscs, MSP (charge of –6). The neurotoxin II (NTII, charge of +4) from cobra venom, an inhibitor of the nicotinic acetylcholine receptor, shows a comparatively low affinity to LPNs containing anionic lipids (POPC/DOPG, 3 : 1 or POPC/DOPS, 4 : 1), and it does not bind to LPNs/POPC. The obtained data show that NTII interacts with the LPN/POPC/DOPS surface in several orientations, and that the exchange process among complexes with different topologies proceeds fast on the NMR timescale. Only one of the possible NTII orientations allows for the previously proposed specific interaction between the toxin and the polar head group of phosphatidylserine from the receptor environment (Lesovoy et al., Biophys. J. 2009. V. 97. № 7. P. 2089–2097). These results indicate that LPNs can be used in structural and functional studies of water-soluble membrane-active peptides (probably except pore-forming ones) and in studies of the molecular mechanisms of peptide-membrane interaction. PMID:25093115

  4. Lipid-protein nanodiscs offer new perspectives for structural and functional studies of water-soluble membrane-active peptides.

    Science.gov (United States)

    Shenkarev, Z O; Lyukmanova, E N; Paramonov, A S; Panteleev, P V; Balandin, S V; Shulepko, M A; Mineev, K S; Ovchinnikova, T V; Kirpichnikov, M P; Arseniev, A S

    2014-04-01

    Lipid-protein nanodiscs (LPNs) are nanoscaled fragments of a lipid bilayer stabilized in solution by the apolipoprotein or a special membrane scaffold protein (MSP). In this work, the applicability of LPN-based membrane mimetics in the investigation of water-soluble membrane-active peptides was studied. It was shown that a pore-forming antimicrobial peptide arenicin-2 from marine lugworm (charge of +6) disintegrates LPNs containing both zwitterionic phosphatidylcholine (PC) and anionic phosphatidylglycerol (PG) lipids. In contrast, the spider toxin VSTx1 (charge of +3), a modifier of Kv channel gating, effectively binds to the LPNs containing anionic lipids (POPC/DOPG, 3 : 1) and does not cause their disruption. VSTx1 has a lower affinity to LPNs containing zwitterionic lipids (POPC), and it weakly interacts with the protein component of nanodiscs, MSP (charge of -6). The neurotoxin II (NTII, charge of +4) from cobra venom, an inhibitor of the nicotinic acetylcholine receptor, shows a comparatively low affinity to LPNs containing anionic lipids (POPC/DOPG, 3 : 1 or POPC/DOPS, 4 : 1), and it does not bind to LPNs/POPC. The obtained data show that NTII interacts with the LPN/POPC/DOPS surface in several orientations, and that the exchange process among complexes with different topologies proceeds fast on the NMR timescale. Only one of the possible NTII orientations allows for the previously proposed specific interaction between the toxin and the polar head group of phosphatidylserine from the receptor environment (Lesovoy et al., Biophys. J. 2009. V. 97. № 7. P. 2089-2097). These results indicate that LPNs can be used in structural and functional studies of water-soluble membrane-active peptides (probably except pore-forming ones) and in studies of the molecular mechanisms of peptide-membrane interaction.

  5. Defensive strategies in Geranium sylvaticum, Part 2: Roles of water-soluble tannins, flavonoids and phenolic acids against natural enemies.

    Science.gov (United States)

    Tuominen, Anu

    2013-11-01

    Geranium sylvaticum is a common herbaceous plant in Fennoscandia, which has a unique phenolic composition. Ellagitannins, proanthocyanidins, galloylglucoses, gallotannins, galloyl quinic acids and flavonoids possess variable distribution in its different organs. These phenolic compounds are thought to have an important role in plant-herbivore interactions. The aim of this study was to quantify these different water-soluble phenolic compounds and measure the biological activity of the eight organs of G. sylvaticum. Compounds were characterized and quantified using HPLC-DAD/MS, in addition, total proanthocyanidins were determined by BuOH-HCl assay and total phenolics by the Folin-Ciocalteau method. Two in vitro biological activity measurements were used: the prooxidant activity was measured by the browning assay and antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Organ extracts were fractionated using column chromatography on Sephadex LH-20 and the activities of fractions was similarly measured to evaluate which polyphenol groups contributed the most to the biological activity of each organ. The data on the activity of fractions were examined by multivariate data analysis. The water-soluble extracts of leaves and pistils, which contained over 30% of the dry weight as ellagitannins, showed the highest pro-oxidant activity among the organ extracts. Fraction analysis revealed that flavonoids and galloyl quinic acids also exhibited high pro-oxidant activity. In contrast, the most antioxidant active organ extracts were those of the main roots and hairy roots that contained high amounts of proanthocyanidins in addition to ellagitannins. Analysis of the fractions showed that especially ellagitannins and galloyl quinic acids have high antioxidant activity. We conclude that G. sylvaticum allocates a significant amount of tannins in those plant parts that are important to the fitness of the plant and susceptible to natural enemies, i

  6. Antibacterial activities of peptides from the water-soluble extracts of Italian cheese varieties.

    Science.gov (United States)

    Rizzello, C G; Losito, I; Gobbetti, M; Carbonara, T; De Bari, M D; Zambonin, P G

    2005-07-01

    Water-soluble extracts of 9 Italian cheese varieties that differed mainly for type of cheese milk, starter, technology, and time of ripening were fractionated by reversed-phase fast protein liquid chromatography, and the antimicrobial activity of each fraction was first assayed toward Lactobacillus sakei A15 by well-diffusion assay. Active fractions were further analyzed by HPLC coupled to electrospray ionization-ion trap mass spectrometry, and peptide sequences were identified by comparison with a proteomic database. Parmigiano Reggiano, Fossa, and Gorgonzola water-soluble extracts did not show antibacterial peptides. Fractions of Pecorino Romano, Canestrato Pugliese, Crescenza, and Caprino del Piemonte contained a mixture of peptides with a high degree of homology. Pasta filata cheeses (Caciocavallo and Mozzarella) also had antibacterial peptides. Peptides showed high levels of homology with N-terminal, C-terminal, or whole fragments of well known antimicrobial or multifunctional peptides reported in the literature: alphaS1-casokinin (e.g., sheep alphaS1-casein (CN) f22-30 of Pecorino Romano and cow alphaS1-CN f24-33 of Canestrato Pugliese); isracidin (e.g., sheep alphaS1-CN f10-21 of Pecorino Romano); kappacin and casoplatelin (e.g., cow kappa-CN f106-115 of Canestrato Pugliese and Crescenza); and beta-casomorphin-11 (e.g., goat beta-CN f60-68 of Caprino del Piemonte). As shown by the broth microdilution technique, most of the water-soluble fractions had a large spectrum of inhibition (minimal inhibitory concentration of 20 to 200 microg/mL) toward gram-positive and gram-negative bacterial species, including potentially pathogenic bacteria of clinical interest. Cheeses manufactured from different types of cheese milk (cow, sheep, and goat) have the potential to generate similar peptides with antimicrobial activity.

  7. Water-soluble undenatured type II collagen ameliorates collagen-induced arthritis in mice.

    Science.gov (United States)

    Yoshinari, Orie; Shiojima, Yoshiaki; Moriyama, Hiroyoshi; Shinozaki, Junichi; Nakane, Takahisa; Masuda, Kazuo; Bagchi, Manashi

    2013-11-01

    Earlier studies have reported the efficacy of type II collagen (C II) in treating rheumatoid arthritis (RA). However, a few studies have investigated the ability of the antigenic collagen to induce oral tolerance, which is defined as active nonresponse to an orally administered antigen. We hypothesized that water-soluble undenatured C II had a similar effect as C II in RA. The present study was designed to examine the oral administration of a novel, water-soluble, undenatured C II (commercially known as NEXT-II) on collagen-induced arthritis (CIA) in mice. In addition, the underlying mechanism of NEXT-II was also identified. After a booster dose (collagen-Freund's complete adjuvant), mice were assigned to control CIA group, or NEXT-II treatment group, to which saline and NEXT-II were administered, respectively. The arthritis index in the NEXT-II group was significantly lower compared with the CIA group. Serum IL-6 levels in the NEXT-II group were significantly lower compared with the CIA group, while serum IL-2 level was higher. Furthermore, oral administration of NEXT-II enhanced the proportion of CD4+CD25+T (Treg) cells, and gene expressions of stimulated dendritic cells induced markers for regulatory T cells such as forkhead box p3 (Foxp3), transforming growth factor (TGF)-β1, and CD25. These results demonstrated that orally administered water-soluble undenatured C II (NEXT-II) is highly efficacious in the suppression of CIA by inducing CD4+CD25+ Treg cells.

  8. Solubility and sorption of petroleum hydrocarbons in water and cosolvent systems

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong; CHEN Shuo; QUAN Xie; ZHAO Yazhi; ZHAO Huimin

    2008-01-01

    The solubility and sorption of oil by uncontaminated clay loam and silt loam soils were studied from water and cosolvent/watersolutions using batch techniques. The data obtained from the dissolution and sorption experinaents were used to evaluate theapplicability of the cosolvent theory to oil as a complex mixture. Aqueous solubility and soil-water distribution coefficients (Kd,w,L/kg) were estimated by extrapolating from cosolvent data, with a log-linear cosolvency model, to the volume fraction of cosolvent(fc) 0, and were compared with direct aqueous measurements. The extrapolated water solubility was 3.16 mg/L, in good agreementwith the directly measured value of 3.83 mg/L. Extrapolated values of Kd,w for the two soils were close to each other but consistentlyhigher than the values from direct aqueous measurements, because of the presence of dissolved organic carbon (DOC). The partitioncoefficient (KDOC) between the DOC and the reely dissolved phase and the OC-normalized sorption coefficient (KOC) were determined.The average values of logKDOC and logKoc were estimated as 4.34 and 3.32, respectively, giving insight into the possibility of oilbecoming mobilized and/or of the soil being remedied. This study revealed that the cosolvency model can be applied to a broader rangeof hydrophobic organic chemicals (HOCs) than has been previously thought. The results aided in a reliable determination of watersolubility and sorption coefficients and provide information about the fate of oil in solvent-contaminated environment.

  9. Equilibrium solubility of carbon dioxide in the amine solvent system of (triethanolamine + piperazine + water)

    Energy Technology Data Exchange (ETDEWEB)

    Chung, P.-Y. [R and D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Chung Li 32023, Taiwan (China); Soriano, Allan N. [R and D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Chung Li 32023, Taiwan (China); School of Chemical Engineering and Chemistry, Mapua Institute of Technology, Manila 1002 (Philippines); Leron, Rhoda B. [R and D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Chung Li 32023, Taiwan (China); Li, M.-H., E-mail: mhli@cycu.edu.t [R and D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Chung Li 32023, Taiwan (China)

    2010-06-15

    In this study, a new set of data for the equilibrium solubility of carbon dioxide in the amine solvent system that consists of triethanolamine (TEA), piperazine (PZ), and water is presented. Equilibrium solubility values were obtained at T = (313.2, 333.2, and 353.2) K and pressures up to 153 kPa using the vapour-recirculation equilibrium cell. The TEA concentrations in the considered ternary (solvent) mixture were (2 and 3) kmol . m{sup -3} and those of PZ's were (0.5, 1.0, and 1.5) kmol . m{sup -3}. The solubility data (CO{sub 2} loading in the amine solution) obtained were correlated as a function of CO{sub 2} partial pressure, system temperature, and amine composition via the modified Kent-Eisenberg model. Results showed that the model applied is generally satisfactory in representing the CO{sub 2} absorption into mixed aqueous solutions of TEA and PZ.

  10. Drug carrier systems based on water-soluble cationic beta-cyclodextrin polymers.

    Science.gov (United States)

    Li, Jianshu; Xiao, Huining; Li, Jiehua; Zhong, YinPing

    2004-07-08

    This study was designed to synthesize, characterize and investigate the drug inclusion property of a series of novel cationic beta-cyclodextrin polymers (CPbetaCDs). Proposed water-soluble polymers were synthesized from beta-cyclodextrin (beta-CD), epichlorohydrin (EP) and choline chloride (CC) through a one-step polymerization procedure by varying molar ratio of EP and CC to beta-CD. Physicochemical properties of the polymers were characterized with colloidal titration, nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC) and aqueous solubility determination. The formation of naproxen/CPbetaCDs inclusion complexes was confirmed by NMR and fourier transform infrared spectroscopy (FT-IR). Cationic beta-CD polymers showed better hemolytic activities than parent beta-CD and neutral beta-CD polymer in hemolysis test. The morphological study of erythrocytes revealed a cell membrane invagination induced by the cationic groups. The effects of molecular weight and charge density of the polymers on their inclusion and release performance of naproxen were also investigated through phase-solubility and dissolution studies. It was found that the cationic beta-CD polymers with high molecular weight or low charge density exhibited better drug inclusion and dissolution abilities.

  11. 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.

  12. Spherical mesoporous silica nanoparticles for loading and release of the poorly water-soluble drug telmisartan.

    Science.gov (United States)

    Zhang, Yanzhuo; Zhi, Zhuangzhi; Jiang, Tongying; Zhang, Jinghai; Wang, Zhanyou; Wang, Siling

    2010-08-03

    The purpose of this study was to develop mesoporous silica nanoparticles (MSNs) loaded with a poorly water-soluble drug, intended to be orally administered, able to improve the dissolution rate and enhance the drug loading capacity. Spherical MSNs were synthesized using an organic template method in an oil/water phase, and large pore diameter MSNs were functionalized with aminopropyl groups through postsynthesis. MSNs as well as the resulting functionalized MSNs were investigated as matrices for loading and release of the model drug telmisartan (TEL). The effects of different pore sizes and surface chemical groups on TEL uptake and release were systematically studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption, X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and HPLC. The total pore volume and the pore diameter of MSNs were the two main factors limiting the maximum drug load capacity. MSNs allow a very high drug loading of about 60% in weight. The release rate of TEL from MSNs with a pore diameter of 12.9 nm was found to be effectively increased and the release rate of TEL from the functionalized MSNs was effectively controlled compared with that from the unmodified MSNs. We believe that the present study will help in the design of oral drug delivery systems for the dissolution enhancement and/or sustained release of poorly water-soluble drugs.

  13. Solubility and some crystallization properties of conglomerate forming chiral drug guaifenesin in water.

    Science.gov (United States)

    Fayzullin, Robert R; Lorenz, Heike; Bredikhina, Zemfira A; Bredikhin, Alexander A; Seidel-Morgenstern, Andreas

    2014-10-01

    The solubility of 3-(2-methoxyphenoxy)-propane-1,2-diol, the well-known chiral drug guaifenesin 1, in water has been investigated by means of polythermal and isothermal approaches. It was found that the solubilities of racemic and enantiomeric diols rac- and (R)-1 depend strongly on temperature. The ternary phase diagram of the guaifenesin enantiomers in water in the temperature range between 10°C and 40°C was constructed. Clear evidence was obtained that rac-1 crystallizes as a stable conglomerate. The Meyerhoffer coefficient for the guaifenesin-water system is more than two and strongly depends on temperature. Neither crystalline hydrates nor polymorphs were detected within the range of conditions covered. Metastable zone width data with regard to primary nucleation were also collected for rac-1 and (R)-1. On the basis of the knowledge acquired, the resolution of racemic guaifenesin by preferential crystallization from solution could be realized successfully. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  14. Improvement of dissolution property of poorly water-soluble drug by supercritical freeze granulation.

    Science.gov (United States)

    Sonoda, Ryoichi; Hara, Yuko; Iwasaki, Tomohiro; Watano, Satoru

    2009-10-01

    The dissolution property of the poorly water-soluble drug, flurbiprofen (FP) was improved by a novel supercritical freeze granulation using supercritical carbon dioxide. Supercritical freeze granulation was defined as a production method of the granulated substances by using the dry ice to generate intentionally for the rapid atomization of the supercritical carbon dioxide to the atmospheric pressure. This process utilized a rapid expansion of supercritical solutions (RESS) process with the mixture of the drug and lactose. In the supercritical freeze granulation, needle-like FP fine particles were obtained which adhered to the surface of lactose particles, which did not dissolve in supercritical carbon dioxide. The number of FP particles that adhered to the surface of particles decreased with an increase in the ratio of lactose added, leading to markedly improve the dissolution rate. This improvement was caused not only by the increase in the specific surface area but also the improvement of the dispersibility of FP in water. It is thus concluded that the supercritical freeze granulation is a useful technique to improve the dissolution property of the poorly water-soluble flurbiprofen.

  15. Structural, functional, and ACE inhibitory properties of water-soluble polysaccharides from chickpea flours.

    Science.gov (United States)

    Mokni Ghribi, Abir; Sila, Assaâd; Maklouf Gafsi, Ines; Blecker, Christophe; Danthine, Sabine; Attia, Hamadi; Bougatef, Ali; Besbes, Souhail

    2015-04-01

    The present study aimed to characterize and investigate the functional and angiotensin-I converting enzyme (ACE) inhibition activities of chickpea water-soluble polysaccharides (CPWSP). Physico-chemical characteristics were determined by nuclear magnetic resonance spectroscopy (NMR), Fourier transform-infrared spectroscopy (FT-IR) analysis, and X-ray diffractometry (XRD). Functional properties (water holding capacity: WHC, water solubility index: WSI, swelling capacity: SC, oil holding capacity: OHC, foaming, and emulsion properties) and ACE activities were also investigated using well-established procedures. The FT-IR spectra obtained for the CPWSP revealed two significant peaks, at about 3500 and 500 cm(-1), which corresponded to the carbohydrate region and were characteristic of polysaccharides. All spectra showed the presence of a broad absorption between 1500 and 670 cm(-1), which could be attributed to CH, CO, and OH bands in the polysaccharides. CPWSP had an XRD pattern that was typical for a semi-crystalline polymer with a major crystalline reflection at 19.6 °C. They also displayed important techno-functional properties (SWC, WSI, WHC, and OHC) that can be modulated according to temperature. The CPWSP were also noted to display good anti-hypertensive activities. Overall, the results indicate that CPWSP have attractive chemical, biological, and functional properties that make them potential promising candidates for application as alternative additives in various food, cosmetic, and pharmaceutical preparations.

  16. Water-soluble phosphate-functionalized polyfluorene as fluorescence biosensors toward cytochrome c

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    An anionic water-soluble polyfluorene derivative, poly(9,9-bis(6′-phosphatehexyl)fluorene-alt-1,4-pheny lene) sodium salt (PFHPNa), was synthesized by Suzuki coupling reaction in DMF/water. Polymer PFHPNa was well soluble in water with a strong blue fluorescence emission. Effect of the side chain length on fluorescence sensory properties was studied by comparing quenching efficiencies toward different quenchers of PFHPNa with a reported polymer poly(9,9-bis(3′-phosphatepropyl)fluorene-alt-1,4-phenylene) sodium salt (PFPPNa), which have different side chains in length. For small molecular quenchers (methylviologen, MV2+) and meso-5,10,15,20-tetrakis-(N-methyl-4-pyridyl)porphine (TMPyP4), polymer PFHPNa had lower sensitivity due to the much longer side chain length. The positively charged metalloprotein cytochrome c could quench fluorescence of conjugated polymers via energy transfer and electron transfer. Moreover, polymer PFHPNa showed higher fluorescence quenching toward large biomolecules than PFPPNa. The corresponding Stern-Volmer (Ksv) value of polymer PFHPNa was determined to be 2.1×108 M-1 for cytochrome c. It could be used as a sensitive and selective fluorescence sensor for protein cytochrome c.

  17. Water-soluble phosphate-functionalized polyfluorene as fluorescence biosensors toward cytochrome c

    Institute of Scientific and Technical Information of China (English)

    QIN ChuanJiang; TONG Hui; WANG LiXiang

    2009-01-01

    An anionic water-soluble polyfluorene derivative, poly(9,9-bis(6'-phosphatehexyl)fluorene-a/t-1,4-pheny-lene) sodium salt (PFHPNa), was synthesized by Suzuki coupling reaction in DMF/water. Polymer PFHPNa was well soluble in water with a strong blue fluorescence emission. Effect of the side chain length on fluo-rescenoe sensory properties was studied by comparing quenching efficiencies toward different quenchers of PFHPNa with a reported polymer poly(g,9-bis(3"phosphatepropyl)fluorene-a/t-1,4-phenylene) sodium salt (PFPPNa), which have different side chains in length. For small molecular quenchers (methylviologen, MV2+) and meso-5,10,15,20-tetrakis-(N-methyl-4-pyridyl)porphine (TMPyP4), polymer PFHPNa had lower sensi-tivity due to the much longer side chain length. The positively charged metalloprotein cytoohrome c could quench fluorescence of conjugated polymers via energy transfer and electron transfer. Moreover, polymer PFHPNa showed higher fluorescence quenching toward large biomolecules than PFPPNa. The corre-sponding Stern-Volmer (Ksv) value of polymer PFHPNa was determined to be 2.1×108 M-1 for cytochrome c. It could be used as a sensitive and selective fluorescence sensor for protein cytochrome c.

  18. The effects of surfactants on the solubility and dissolution profiles of a poorly water-soluble basic drug, carvedilol.

    Science.gov (United States)

    Incecayir, T

    2015-12-01

    This study investigated the most suitable surfactant medium for the dissolution testing of a poorly soluble basic drug, namely, carvedilol reflecting the in vivo behavior. Sodium lauryl sulfate (SLS), hexadecyltrimethylammonium bromide (CTAB) and polysorbate 80 were used as anionic, cationic and nonionic surfactants, respectively. Saturation solubilities of carvedilol were determined in the presence of SLS, CTAB and polysorbate 80 (0.5, 1 and 2% (w/v)) at pH 1.2 and 6.8. Dissolution behaviors of the commercial tablets were studied using USP apparatus II in pH 1.2, 4.5 and 6.8 buffers and pH 6.8 dissolution media with 0.5% (w/v) SLS, polysorbate 80 and CTAB. Polysorbate 80 enhanced the solubility of carvedilol irrespective of pH, while SLS and CTAB exhibited larger solubilization effect than polysorbate 80 depending on pH and the ionic nature of the surfactant. Based on in vitro dissolution profile similarity, pH 6.8 dissolution medium with 0.5% (w/v) polysorbate 80 was found to be the most biorelevant medium, which probably reflects the bioequivalence of test products to the reference product of carvedilol.

  19. 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.

  20. 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.

  1. Spectral Properties of a Water-Soluble Squaraine Dye and Its Application in Cell Fluorescent Imaging

    Science.gov (United States)

    Hu, L.; Yuan, H.; Li, Q. Q.; Jin, J. C.; Chang, W. G.; Yan, Z. Q.

    2015-09-01

    A water-soluble bis-1,3,5-trihydroxybenzene squaraine dye (t-OH-SQ) with a D-π-A-π-D conjugated structure was identified and prepared. After its structure was characterized by FTIR, 1H NMR and elemental analysis, the UV-Vis absorption and fluorescent spectra of the target dye were studied in detail. The results showed that t-OH-SQ combining multi-hydroxyl groups possessed excellent optical properties changing with pH and solvents. In aqueous solution under physiological pH ~ 7-8, it had especially high near-infrared fluorescence, which might be a latent application for cell fluorescent imaging.

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

    Directory of Open Access Journals (Sweden)

    William H Karasov

    Full Text Available 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 (P<0.001. Surprisingly, the apparent rates of absorption in birds 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

  3. Biomolecule-assisted synthesis of highly stable dispersions of water-soluble copper nanoparticles.

    Science.gov (United States)

    Xiong, Jing; Wu, Xue-dong; Xue, Qun-ji

    2013-01-15

    Water-soluble and highly stable dispersions of copper nanoparticles were obtained using a biomolecule-assisted synthetic method. Dopamine was utilized as both reducing and capping agent in aqueous medium. The successful formation of DA-stabilized copper particles was demonstrated by ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), Zeta potential measurement, and Fourier transform infrared spectroscopy (FT-IR). The mechanism of dopamine on the effective reduction and excellent stability of copper nanoparticles was also discussed. This facile biomolecule-assisted technique may provide a useful tool to synthesize other nanoparticles that have potential application in biotechnology.

  4. Active Oxygen Radical Scavenging Ability of Water-Soluble β-Alanine C60 Adducts

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Water-soluble β-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2-and hydroxyl radicalOH were studied by autoxidation ofpyrogallol and chemiluminescence, respectively. It was found that β-alanine C60 adducts showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.15 mg/mL and 0.048 mg/mL, respectively. The difference should be mainly attributed to the different scavenging mechanisms.

  5. [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.

  6. 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...... squares regression of the amino acid data and the sensory results indicated that bouillon taste was related to a mixture of different amino acids and peptides, that potato odor in particular correlated with high content of tyrosine, free and as the peptide residue, that bitterness was related to the level...

  7. Water soluble reduced graphene oxide as an efficient photoluminescence quencher for semiconductor quantum dots

    Science.gov (United States)

    Tang, Haiping; Sun, Luwei; He, Haiping

    2017-02-01

    Chemically derived water soluble reduced graphene oxide (rGO) is synthesized via a two-step reduction approach assisted with sulfonation. X-ray photoelectron spectroscopy confirms the removal of oxygen-related groups from GO. The obtained rGO can effectively quench the photoluminescence (PL) of CdTe quantum dots. Concentration- and volume-dependent quenching behaviors are investigated to reveal the quenching mechanism. The Stern-Volmer plot shows exponential dependence on the rGO concentration, indicating that "sphere of action" model works when the extent of quenching is large.

  8. Water-soluble constituents of anise: new glucosides of anethole glycol and its related compounds.

    Science.gov (United States)

    Ishikawa, Toru; Fujimatu, Eiko; Kitajima, Junichi

    2002-11-01

    From the water-soluble portion of the methanolic extract of the fruit of anise (Pimpinella anisum L.), which has been used as a spice and medicine since antiquity, twelve new and five known glucosides of phenylpropanoids, including four stereoisomers of anethole glycol 2'-O-beta-D-glucopyranoside and four stereoisomers of 1'-(4-hydroxyphenyl)propane-1',2'-diol 2'-O-beta-D-glucopyranoside were isolated together with anethole glycols and guaiacyl glycerol. The structures of the new compounds were clarified by spectral investigation.

  9. 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.

  10. Reinforced films based on cross-linked water-soluble sulfonated carbon nanotubes with sulfonated polystyrene.

    Science.gov (United States)

    Dai, Ying; Haiping, Hong; Guiver, Michael; Welsh, Jeffry S

    2009-09-01

    Reinforced films based on sulfonated polystyrene cross-linked with water-soluble sulfonated carbon nanotubes were fabricated using a free-standing film-making method. Transmission and scanning electron microscopy (TEM and SEM), and X-ray photoelectron spectroscopy (XPS) were used to verify the cross-linking reaction. The mechanical properties of these films demonstrated that the tensile strength increases with an increase in the sulfonated nanotube concentration. At 5 wt% nanotube loading, the tensile strength increased 84% compared with polymer containing no nanotube loading. The relationships between structure and mechanical properties are discussed and a possible direction for making ultra thin and ultra lightweight film is proposed.

  11. Reinforced membrane based on crosslink reaction between water soluble sulfonated carbon nanotubes and sulfonated polystyrene

    Science.gov (United States)

    Dai, Ying; Hong, Haiping; Welsh, Jeffry S.

    2008-08-01

    Reinforced films based on sulfonated polystyrene cross-linked with water-soluble sulfonated carbon nanotubes were fabricated using a free-standing film-making method. Transmission and scanning electron microscopy, X-ray photoelectron spectroscopy, and thermo-gravimetric analysis were used to verify the cross-linking reaction. The mechanical properties of these films demonstrated that the tensile strength increases with an increase in the sulfonated nanotube concentration. At 5 wt% nanotube loading, the tensile strength increased 84% compared with polymer containing no nanotube loading. The relationships between structure and mechanical properties are discussed and a possible direction for making ultra thin and ultra lightweight film is proposed

  12. Water-Soluble Metalloporphyrins as Mimics of Heme-containing Enzymes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This letter compared catalase-, peroxidase-and cytochrome P450-1ike catalytic activities of 15 water-soluble metalloporphyrins produced from Fe, Mn and Co ions and 5 porphyrins. The metalloporphyrins with Fe and Mn as central ions show relatively high catalytic activities of catalase and peroxidase at pH 11.0. Only Mn-meso-tetrakis (4-N-methylpyridinium) porpho-phine of the 15 metalloporphyfins exhibits high cytochrome P450-1ike activity. Effects of imidazole on the catalytic reactions were also studied.

  13. Singlet oxygen generation from water-soluble quantum dot-organic dye nanocomposites.

    Science.gov (United States)

    Shi, Lixin; Hernandez, Billy; Selke, Matthias

    2006-05-17

    Water-soluble quantum dot-organic dye nanocomposites have been prepared via electrostatic interaction. We used CdTe quantum dots with diameters up to 3.4 nm, 2-aminoethanethiol as a stabilizer, and meso-tetra(4-sulfonatophenyl)porphine dihydrochloride (TSPP) as an organic dye. The photophysical properties of the nanocomposite have been investigated. The fluorescence of the parent CdTe quantum dot is largely suppressed. Instead, indirect excitation of the TSPP moiety leads to production of singlet oxygen with a quantum yield of 0.43. The nanocomposite is sufficiently photostable for biological applications.

  14. Relationship between water solubility of chlorobenzenes and their effects on a freshwater green alga

    Energy Technology Data Exchange (ETDEWEB)

    Wong, P.T.S.; Chau, Y.K.; Rhamey, J.S.; Docker, M.

    1984-01-01

    The effective concentrations of benzene and 12 chlorobenzenes that reduced 50% of the primary productivity (EC/sub 50/) of a freshwater green alga, Ankistrodesmus falcatus, were determined. Benzene was the least toxic chemical and the toxicity increased as the degree of chlorine substitution in the aromatic ring increased. No EC/sub 50/ value could be obtained for HCB. A quantitative relationship was found to exist between water solubility, lipophilicity and the EC/sub 50/. A good correlation was also observed between the EC/sub 50/ for this alga and other toxicity data for various aquatic biota.

  15. Water-soluble material on aerosols collected within volcanic eruption clouds ( Fuego, Pacaya, Santiaguito, Guatamala).

    Science.gov (United States)

    Smith, D.B.; Zielinski, R.A.; Rose, W.I.; Huebert, B.J.

    1982-01-01

    In Feb. and March of 1978, filter samplers mounted on an aircraft were used to collect the aerosol fraction of the eruption clouds from three active Guatemalan volcanoes (Fuego, Pacaya, and Santiaguito). The elements dissolved in the aqueous extracts represent components of water-soluble material either formed directly in the eruption cloud or derived from interaction of ash particles and aerosol components of the plume. Calculations of enrichment factors, based upon concentration ratios, showed the elements most enriched in the extracts relative to bulk ash composition were Cd, Cu, V, F, Cl, Zn, and Pb.-from Authors

  16. Preparation of fructone catalyzed by water-soluble Br(φ)nsted acid ionic liquids

    Institute of Scientific and Technical Information of China (English)

    Yuan Yuan Wang; Rong Wang; Liang Chun Wu; Li Yi Dai

    2007-01-01

    Fructone (2-methyl-2-ethylacetoacetate-1,3-dioxolane), a flavouring material, has been synthesized from ethyl acetoacetate and glycol using five water-soluble Br(φ)nsted acid ionic liquids as catalysts for the first time. The used Br(φ)nsted acid ionic liquids include [Hmim]Tfa, [Hmim]Tsa, [Hmim]BF4, [Bmim]HSO4, [Bmim]H2PO4, and [Hmim]BF4 showed the highest catalytic activity for the preparation of fructone. After reaction, the product could be isolated from the reaction system automatically, and the ionic liquid could be directly reused without dehydration.

  17. 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.

  18. 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.

  19. Estudo da solubilidade das proteínas de extratos hidrossolúveis de soja em pó Protein solubility study of water soluble soybean dried extracts

    Directory of Open Access Journals (Sweden)

    Judith Liliana SOLÓRZANO LEMOS

    1997-12-01

    Full Text Available Foi estudado o efeito da homogeneização e da adição de sacarose, sulfito de sódio e lecitina na solubilidade das proteínas do extrato hidrossolúvel de soja em pó (EHSP.O calor aplicado durante o tratamento térmico do extrato hidrossolúvel de soja líquido (EHSL a 90 ± 2°C por 15 minutos e a secagem afetaram drasticamente a solubilidade das proteínas, provocando uma diminuição no índice de solubilidade do nitrogênio (ISN, de 90,57 % no grão de soja descascado para 25,31 % no EHSP usado como controle. Porém, os valores de ISN para os EHSP que continham sacarose, sulfito de sódio e lecitina, assim como daquele que foi homogeneizado foram significativamente maiores do que o do EHSP (controle que sofreu apenas tratamento térmico.The effect of homogenization and addition of sodium sulphite, sucrose and lecithin was studied on the protein solubility of water soluble soybean extracts (WSSE. The heat treatment of the water soluble soybean liquid extracts at 90 ± 2°C for 15 minutes and drying had a large effect on the protein solubility, decreasing the nitrogen solubility index (NSI from 90.57% in the dehulled soybean to 25.31% in WSSE used as control. However, the NSI values of the WSSE containing sucrose, sodium sulphite and lecithin as well as that one homogenized were significantly higher than the NSI of the WSSE (control which recieved heat treatment only.

  20. 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

  1. Water-soluble chemistry and weathering characteristics of some tills in Western Dronning Maud Land, Antarctica

    Directory of Open Access Journals (Sweden)

    Lintinen, P.

    1997-12-01

    Full Text Available The water-soluble chemistry and weathering characteristics of tills were studied on three nunataks with differing bedrock characteristics in the Vestfjella and Heimefrontfjella areas of the Western Dronning Maud Land, Antarctica. The chemical analyses were performed using ion chromatography and ICP-AES. The relative weathering characteristics of the till surface boulders was assessed in study locations. No colour differences were observed in test pits dug in Basen and Utpostane nunataks at Vestfjella, whereas the till in Mygehenget nunatak at Heimefrontfjella has a pronounced soil profile in which the surface part has a banded rusty brown and light-coloured accumulations. The highest concentrations of readily soluble ions were recorded in the Mygehenget samples characterized by high (SO42- (5800-39000 ppm and Mg concentrations (540-6000 ppm, while the Basen samples had the highest concentrations of Fe2+(23-390 ppm, Al3+ (60-1000 ppm and Si4+ (23-1700 ppm and the Utpostane samples the lowest ones. The SO4/Na+, Na+/CI- and Mg2+/Na+ ratios for the samples differ markedly from those typically encountered in sea water. The presence of the highest concentrations of many of the analysed ions in the Mygehenget soil samples is in line with the advanced weathering of the surface boulders. The high Fe2+ , Si4+ and Al3+ concentrations in the Basen samples may be attributable to the weathering of olivine alteration products.

  2. Lightsticks content toxicity: effects of the water soluble fraction on the oyster embryonic development.

    Science.gov (United States)

    de Araujo, Milena Maria Sampaio; Menezes Filho, Adalberto; Nascimento, Iracema Andrade; Pereira, Pedro Afonso P

    2015-11-01

    Lightsticks are artifacts used as attractors in a type of commercial fishery, known as surface longline gear. Despite the excessive use, the contamination risks of these devices have not yet been properly investigated. This research aimed to fill up this gap by determining the chemical composition and the toxicity of lightsticks recently activated, compared to those one year after activation and to the ones collected on the beaches. The analyzes were carried out by Gas Chromatography coupled with Mass Spectrometry (GC-MS). Additionally, the variations in composition and the toxicity of their sea Water Soluble Fractions (WSF) were evaluated based on the WSF-effects of Crassostrea rhizophorae embryonic development. The GC-MS analysis made possible the identification of nineteen substances in the water soluble fraction of the lightsticks, such as dibutyl phthalate (DBP) and dimethyl phthalate (DMP). The value of the WSF-effective concentration (EC50) was in an average of 0.35%. After one year of the lightsticks activation, the toxicity was even higher (0.65%). Furthermore, other substances, also present in the lightsticks-WSF caused persistent toxicity even more dangerous to the environment than DBP and DMP. This essay discusses their toxicity effects and possible environment damages. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. 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.

  4. Lipid nanoparticles with no surfactant improve oral absorption rate of poorly water-soluble drug.

    Science.gov (United States)

    Funakoshi, Yuka; Iwao, Yasunori; Noguchi, Shuji; Itai, Shigeru

    2013-07-15

    A pharmacokinetic study was performed in rats to evaluate the oral absorption ratios of nanoparticle suspensions containing the poorly water-soluble compound nifedipine (NI) and two different types of lipids, including hydrogenated soybean phosphatidylcholine and dipalmitoylphosphatidylglycerol. NI-lipid nanoparticle (LN) suspensions with a mean particle size of 48.0 nm and a zeta potential of -57.2 mV were prepared by co-grinding combined with a high-pressure homogenization process. The oral administration of NI-LN suspensions to rats led to a significant increase in the NI plasma concentration, and the area under the curve (AUC) value was found to be 108 min μg mL⁻¹, indicating a 4-fold increase relative to the NI suspensions. A comparison of the pharmacokinetic parameters of the NI-LN suspensions with those of the NI solution prepared using only the surfactant polysorbate 80 revealed that although the AUC and bioavailability (59%) values were almost identical, a rapid absorption rate was still observed in the NI-LN suspensions. These results therefore indicated that lipid nanoparticles prepared using only two types of phospholipid with a mean particle size of less than 50 nm could improve the absorption of the poorly water-soluble drug. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Increasing the oral bioavailability of the poorly water soluble drug itraconazole with ordered mesoporous silica.

    Science.gov (United States)

    Mellaerts, Randy; Mols, Raf; Jammaer, Jasper A G; Aerts, Caroline A; Annaert, Pieter; Van Humbeeck, Jan; Van den Mooter, Guy; Augustijns, Patrick; Martens, Johan A

    2008-05-01

    This study aims to evaluate the in vivo performance of ordered mesoporous silica (OMS) as a carrier for poorly water soluble drugs. Itraconazole was selected as model compound. Physicochemical characterization was carried out by SEM, TEM, nitrogen adsorption, DSC, TGA and in vitro dissolution. After loading itraconazole into OMS, its oral bioavailability was compared with the crystalline drug and the marketed product Sporanox in rabbits and dogs. Plasma concentrations of itraconazole and OH-itraconazole were determined by HPLC-UV. After administration of crystalline itraconazole in dogs (20mg), no systemic itraconazole could be detected. Using OMS as a carrier, the AUC0-8 was boosted to 681+/-566 nM h. In rabbits, the AUC0-24 increased significantly from 521+/-159 nM h after oral administration of crystalline itraconazole (8 mg) to 1069+/-278 nM h when this dose was loaded into OMS. Tmax decreased from 9.8+/-1.8 to 4.2+/-1.8h. No significant differences (AUC, Cmax, and Tmax) could be determined when comparing OMS with Sporanox in both species. The oral bioavailability of itraconazole formulated with OMS as a carrier compares well with the marketed product Sporanox, in rabbits as well as in dogs. OMS can therefore be considered as a promising carrier to achieve enhanced oral bioavailability for drugs with extremely low water solubility.

  6. 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.

  7. [Immunoproteomics of non water-soluble allergens from 4 legumes flours: peanut, soybean, sesame and lentil].

    Science.gov (United States)

    Bouakkadia, Hayette; Boutebba, Aissa; Haddad, Iman; Vinh, Joëlle; Guilloux, Laurence; Sutra, Jean-Pierre; Sénéchal, Hélène; Poncet, Pascal

    2015-01-01

    Peanut, soybean, sesame and lentil are members of legumes worldwide consumed by human that can induce food allergy in genetically predisposed individuals. Several protein allergens, mainly water-soluble, have been described. We studied the non water-soluble fraction from these 4 food sources using immunoproteomics tools and techniques. Flour extracts were solubilized in detergent and chaotropes and analysed in 1 and 2 dimensional gel electrophoresis (2D). Results showed numerous proteins exhibiting wide ranges of isoelectric points and relative molecular masses. When IgE immunoreactivities of 18 food allergy patients were individually tested in 1 and 2D western-blots, a very diversified IgE repertoire was observed, reflecting extensive cross-reactivities but also co-sensitizations. Besides already well known and characterized allergens, mass spectrometry analysis allowed the identification of 22 allergens undescribed until now: 10 in peanut, 2 in soybean, 3 in sesame and 7 in lentil. Three allergens are legume storage proteins and the others belong to transport proteins, nucleotide binding proteins and proteins involved in the regulation of metabolism. Seven proteins are potentially similar to allergens described in plants and fungi and 11 are not related to any known allergen. Our results contribute to increase the repertoire of legume allergens that may improve the diagnosis, categorize patients and thus provide a better treatment of patients.

  8. Water-soluble calix[4]resorcinarenes with hydroxyproline groups as chiral NMR solvating agents.

    Science.gov (United States)

    O'Farrell, Courtney M; Chudomel, J Matthew; Collins, Jan M; Dignam, Catherine F; Wenzel, Thomas J

    2008-04-04

    Water-soluble calix[4]resorcinarenes containing 3- and 4-hydroxyproline, d-nipecotic acid, (S)-2-(methoxymethyl)pyrrolidine, (S)-2-pyrrolidine methanol, and (S,S)-(+)-2,4-bis(methoxymethyl)pyrrolidine substituents are synthesized and evaluated as chiral NMR solvating agents. The derivatives with the hydroxyproline groups are especially effective at causing enantiomeric discrimination in the spectra of water-soluble cationic and anionic compounds with pyridyl, phenyl, and bicyclic aromatic rings. Binding studies show that mono- and ortho-substituted phenyl rings associate within the cavity of the calix[4]resorcinarenes, as do naphthyl rings with mono-, 2,3-, and 1,8-substitution patterns. Anthracene derivatives with an amino or sulfonyl group at the 1-position bind within the cavity, as well. Aromatic resonances of the substrates exhibit substantial upfield shifts because of shielding from the aromatic rings of the calix[4]resorcinarene. The effectiveness of the reagents at producing chiral recognition in 1H NMR spectra is demonstrated with sodium mandelate, the sodium salt of tryptophan, and doxylamine succinate. While no one reagent is consistently the most effective, the calix[4]resorcinarenes with trans-4-hydroxyproline and trans-3-hydroxyproline moieties generally produce the largest nonequivalence in the 1H NMR spectra of the substrates.

  9. Release of small water-soluble drugs from multiblock copolymer microspheres: a feasibility study.

    Science.gov (United States)

    Sohier, J; van Dijkhuizen-Radersma, R; de Groot, K; Bezemer, J M

    2003-03-01

    Poly(ethylene glycol)-terephthalate/poly(butylene terephthalate) (PEGT/PBT) multiblock copolymer was investigated as a possible matrix for controlled delivery of small water-soluble drugs. Two molecules were selected as sustained release candidates from microspheres: leuprorelin acetate (peptide of Mw = 1270 D) and vitamin B(12) (Mw = 1355 D). First, vitamin B(12)-loaded microspheres were prepared using a double emulsion method and preparation parameters were varied (surfactant in the first emulsion and copolymer composition). The resulting microsphere structure, entrapment efficiency and release rate were evaluated. Vitamin B(12)-loaded microsphere parameters could easily be tailored to achieve specific requirements. The addition of surfactant in the first preparation process led to a significant increase of the microsphere entrapment efficiency, whereas the decrease of the PEGT copolymer content allowed the release rates from microspheres to be precisely decreased. However, leuprorelin acetate-loaded microspheres did not show the same characteristics when prepared with the same parameters, possibly because of a high water solubility discrepancy between the vitamin B(12) and the peptide. This study shows the suitability of PEGT/PBT microspheres as a controlled release system for vitamin B(12), but not for leuprorelin acetate. It also underlines the necessity of tailored development for each individual drug and emphasizes the risk of using model molecules. Copyright 2002 Elsevier Science B.V.

  10. Rhodamine B piperazinoacetohydrazine: a water-soluble spectroscopic reagent for pyruvic acid labeling.

    Science.gov (United States)

    Jia, Jia; Wang, Ke; Shi, Wen; Chen, Suming; Li, Xiaohua; Ma, Huimin

    2010-06-11

    A new water-soluble reagent, rhodamine B piperazinoacetohydrazine (RBPH), with improved spectroscopic and reaction properties, has been developed and characterized for pyruvic acid labeling. The reagent RBPH is designed and synthesized by using rhodamine B as a spectroscopic unit, and hydrazine as a carbonyl-specific labeling unit; the two units are connected by a well-chosen linker of piperazine, which prohibits the formation of the nonfluorescent spirocyclic structure of rhodamine B, thereby keeping the spectroscopic response of the reagent in a stable state. Such a design enables RBPH not only to maintain its excellent spectroscopic properties over a wide pH range, but also to exist as a stable cation with high water solubility. Moreover, the hydrazino group of RBPH is expected to react selectively with carbonyl compounds under mild conditions through the rapid formation of hydrazones. These important features make RBPH of great potential use in the labeling of aldehydes or ketones in various biosystems, and such an application of RBPH as a precolumn derivatizing reagent has been successfully demonstrated on the analysis of pyruvic acid in human serum by high-performance liquid chromatography with common UV/Vis detection.

  11. Water-Soluble Conjugated Polymers: Self-Assembly and Biosensor Applications

    Science.gov (United States)

    Bazan, Guillermo

    2005-03-01

    Homogeneous assays can be designed which take advantage of the optical amplification of conjugated polymers and the self-assembly characteristic of aqueous polyelectrolytes. For example, a ssDNA sequence sensor comprises an aqueous solution containing a cationic water soluble conjugated polymer such as poly(9,9-bis(trimethylammonium)-hexyl)-fluorene phenylene) with a peptide nucleic acid (PNA) labeled with a dye (PNA-C*). Signal transduction is controlled by hybridization of the neutral PNA-C* probe and the negative ssDNA target, resulting in favorable electrostatic interactions between the hybrid complex and the cationic polymer. Distance requirements for Förster energy transfer are thus met only when ssDNA of complementary sequence to the PNA-C* probe is present. Signal amplification by the conjugated polymer provides fluorescein emission >25 times higher than that of the directly excited dye. Transduction by electrostatic interactions followed by energy transfer is a general strategy. Examples involving other biomolecular recognition events, such as DNA/DNA, RNA/protein and RNA/RNA, will also be provided. The mechanism of biosensing will be discussed, with special attention to the varying contributions of hydrophobic and electrostatic forces, polymer conformation, charge density, local concentration of C*s and tailored defect sites for aggregation-induced optical changes. Finally, the water solubility of these conjugated polymers opens possibilities for spin casting onto organic materials, without dissolving the underlying layers. This property is useful for fabricating multilayer organic optoelectronic devices by simple solution techniques.

  12. P2O5 assisted green synthesis of multicolor fluorescent water soluble carbon dots.

    Science.gov (United States)

    Babar, Dipak Gorakh; Sonkar, Sumit Kumar; Tripathi, Kumud Malika; Sarkar, Sabyasachi

    2014-03-01

    A low cost synthesis of multicolor fluorescent carbon dots (C-dots) from edible sugars is described here. Common sugars like dextrose, lactose or maltose in aqueous medium gets dehydrated using phosphorus pentoxide (P2O5). The reaction is facile and completed within few minutes to form insoluble carbon (C-dots) mostly having the graphitic (G-band, Raman) sp2 hybridized carbon atoms (C-atoms). This insoluble carbon on oxidative treatment with nitric acid produced disordered sp3 (D-band retaining G-band, Raman) hybridized C-atoms, originated from the graphitic pool with sp2 hybridized C-atoms. This high density assimilation of self passivated "surfacial defects" become emissive during electronic transitions. Surfacial defects due to high degree of electrophilic carboxylation create the water soluble version of multicolor fluorescent C-dots as "water soluble fluorescent carbon dots" (wsFCDs). wsFCDs being itself self-passivated imposes the tunable multicolor emission throughout the visible spectrum without having any external coating and surface passivation and could be used as multicolor fluorescent probe especially in the emerging field of optical bio-imaging.

  13. Synthesis of mesoporous silica nanoparticles and drug loading of poorly water soluble drug cyclosporin A

    Directory of Open Access Journals (Sweden)

    A Lodha

    2012-01-01

    Full Text Available Mesoporous silica nanoparticles (MSNs are introduced as chemically and thermally stable nanomaterials with well-defined and controllable morphology and porosity. It is shown that these particles possess external and internal surfaces that can be selectively functionalized with multiple organic and inorganic groups. Silica nano-particles were synthesized by chemical methods from tetraethylorthosilicate (TEOS, methanol (CH3OH and deionised water in the presence of sodium hydroxide as catalyst at 80°C temperature. The nature and morphology of particles was investigated by scanning electron microscopy (SEM, N2 adsorption/desorption method using BET instrument and X-ray diffraction (XRD. Silica nanoparticles are applicable to a wide range of therapeutic entities from small molecule to peptides and proteins including hydrophobic and hydrophilic entities. Drug loading does not require chemical modification of the molecule; there are no changes in the drug structure or activity after loading and subsequent release of the drug. Thus, well suited to solve formulation problems associated with hydrophobic drugs such as peptide and protein drugs like cyclosporine A. Silica nanoparticles improved the solubility of poorly water soluble drugs and enhanced the absorption and bioavailability of these compounds.

  14. Characterization of water-soluble ion species in urban ambient particles.

    Science.gov (United States)

    Lin, Jim Juimin

    2002-04-01

    Concentrations and distributions of water-soluble ion species contained in ambient particles were measured in a coastal urban area, Kaohsiung City, Taiwan. PM10 and PM2.5 samples were collected using a dichotomous sampler from November 1998 to April 1999 and were analyzed for water-soluble ion species with ion chromatography. On the average, ion species measured in this study accounted for 42.2% of the PM2.5 and 35.7% of the PM10. It was found that SO4(2-) , NO3-, and NH4+ dominated the identifiable components within both fine (PM2.5) and coarse (PM2.5-10) fractions, and occupied 90.0% and 80.6% of total dissolved ionic concentrations for PM2.5 and PM10. The secondary aerosol formed through the NOx/SO2 gas-to-particle conversion was estimated based on the oxidation ratio of sulfur and nitrogen (SOR and NOR, respectively), i.e., sulfate sulfur/nitrate nitrogen to total sulfur/total nitrogen. The average SOR/NOR values were 0.25/0.07 and 0.29/0.12 for PM25 and PM10, respectively. The high SOR and NOR values obtained in this study suggested that there existed a secondary formation of SO4(2-) from SO2 along with NO3- from NOx in the atmosphere.

  15. Incorporation of titanate nanosheets to enhance mechanical properties of water-soluble polyamic acid

    Science.gov (United States)

    Harito, C.; Bavykin, Dmitry V.; Walsh, Frank C.

    2017-07-01

    Pyromeliticdianhydride (PMDA) and 4’,4’-oxydianiline (ODA) were used as monomers of polyimide. To synthesise a water soluble polyimide precursor (polyamic acid salt), triethylamine (TEA) was added to polyamic acid with a TEA/COOH mole ratio of 1:1. Titanate nanosheets were synthesised by solid-state reaction, ion-exchanged with acid, and exfoliated by TEA. Exfoliated titanate nanosheets were mixed with water soluble polyamic acid salt as reinforcing filler. Drop casting was deployed to synthesise polyamic acid/titanate nanosheet nanocomposite films. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to study the morphology and dispersion of nanosheets in the colloidal dispersion and the solid film composite. Modulus and hardness of nanocomposites was provided by nanoindentation. Hardness increased by 90% with addition of 2% TiNS while modulus increased by 103% compared to pure polymer. This behaviour agrees well with Halpin-Tsai theoretical predictions up to 2 wt% filler loading; agglomeration occurs at higher concentrations.

  16. RADICAL GRAFTING REACTIONS ONTO STARCH AND OTHER WATER-SOLUBLE COPOLYMERS IN ISOLATED GEL DROPLETS

    Institute of Scientific and Technical Information of China (English)

    ZHANG Liansheng; A.F.Johnson

    1993-01-01

    A novel radical grafting copolymerization process has been designed for water-soluble polymers which avoids the problems of conducting grafting reactions in highly viscous polymerization media.A variety of water-soluble graft copolymers having starch or dextran as the backbone chain with grafted side chains of polyacrylamide (-AM-),poly (acrylic acid) (-AA-),poly (acrylamide-co-acrylic acid) (-AM-NH4AA-) or poly (acrylamide-co-2-acrylamido-2-methyl-1-propanesulphinic acid)(-AM-AMPS-) have been synthesized in gel droplets using a ceric sulphate redox initiator,and their properties compared.The reaction conditions were optimized taking into account reaction kinetic data and the observed properties of the products produced under different reaction conditions.The effects of the ratios of [backbone]/[graft monomer],[AM]/[AA]/[AMPS],[Ce4+]/[S2O8=] and pH value on the reaction rate,conversion,grafting degree,grafted chain length and the product molecular weight have been investigated.

  17. Influence of polymethacrylates and compritol on release profile of a highly water soluble drug metformin hydrochloride

    Directory of Open Access Journals (Sweden)

    Sunita Dahiya

    2015-01-01

    Full Text Available Aims: The present investigation studied effect of polymethacrylates Eudragit RSPO, Eudragit RLPO and compritol 888 ATO on release profile of highly water soluble drug metformin hydrochloride (MET. Materials and Methods: The solid dispersions were prepared using drug:polymer ratios 1:1 and 1:5 by coevaporation and coprecipitation techniques. Solid dispersions were characterized by infrared Spectroscopy (IR, differential scanning calorimetry (DSC, X-ray diffractometry (XRD as well as content uniformity, in vitro dissolution studies in 0.1 N HCl pH 1.2, phosphate buffer pH 6.8. Results and Discussion: Results of the studies suggested that there were progressive disappearance or changes of prominent peaks in IR, X-ray diffraction and thermotropic drug signals in coevaporates and coprecipitates with increased amount of polymers. Moreover, the in vitro release of highly water soluble MET could be extended at higher drug:polymer ratios. Conclusion: It was summarized that Eudragit RLPO had greater capacity of drug release than Eudragit RSPO and Comproitol 888 and its coevaporates in 1:5 drug:polymer ratio (F11 displayed extended drug release with comparatively higher dissolution rates (92.15 % drug release at 12 hour following near Zero order kinetics (r² =0.9822.

  18. Dissolution rate measurements of sea water soluble pigments for antifouling paints

    DEFF Research Database (Denmark)

    Yebra, Diego Meseguer; Kiil, Søren; Erik Weinell, Claus

    2006-01-01

    The dissolution of soluble pigments from both tin-based and tin-free chemically active antifouling (AF) paints is a key process influencing their polishing and biocide leaching rates. In this context, a low time- and resources-consuming method capable of screening the pigment behaviour in the sea......The dissolution of soluble pigments from both tin-based and tin-free chemically active antifouling (AF) paints is a key process influencing their polishing and biocide leaching rates. In this context, a low time- and resources-consuming method capable of screening the pigment behaviour...... in the search for the most promising materials or mixtures is of great interest. A preliminary attempt to develop such a method is presented in this paper based on the widely used ZnO pigments. While highly pure, nano-polished, monocrystalline ZnO substrates yielded very low dissolution rates in the order of 17...... of defects in the lattice structure, are hypothesised to be responsible for the faster sea water attack of the pellets compared to the ZnO crystals. In any case, the ZnO dissolution rates reported in this paper are markedly lower than those associated with the sea water dissolution of cuprous oxide (Cu2O...

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

    Energy Technology Data Exchange (ETDEWEB)

    Dumesic, James A.; Luterbacher, Jeremy S.

    2015-06-02

    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.

  20. Antioxidant property of water-soluble polysaccharides from Poria cocos Wolf using different extraction methods.

    Science.gov (United States)

    Wang, Nani; Zhang, Yang; Wang, Xuping; Huang, Xiaowen; Fei, Ying; Yu, Yong; Shou, Dan

    2016-02-01

    Poria cocos Wolf is a popular traditional medicinal plant that has invigorating activity. Water-soluble polysaccharides (PCPs) are its main active components. In this study, four different methods were used to extract PCPs, which include hot water extraction (PCP-H), ultrasonic-assisted extraction (PCP-U), enzyme-assisted extraction (PCP-E) and microwave-assisted extraction (PCP-M). Their chemical compositions and structure characterizations were compared. In vitro antioxidant activities were studied on the basis of DPPH radical, hydroxyl radical, reducing power and metal chelating ability. The results showed that PCPs were composed of mannose, glucose, galactose, and arabinose, and had typical IR spectra characteristics of polysaccharides. Compared with other PCPs, PCP-M had lower neutral sugar content, higher mannose content and higher uronic acid content. The molecular weight were determined as PCP-Ecocos Wolf.

  1. Two-Photon Photodynamic Therapy by Water-Soluble Self-Assembled Conjugated Porphyrins

    Directory of Open Access Journals (Sweden)

    Kazuya Ogawa

    2013-01-01

    Full Text Available Studies on two-photon absorption (2PA photodynamic therapy (PDT by using three water-soluble porphyrin self-assemblies consisting of ethynylene-linked conjugated bis (imidazolylporphyrin are reviewed. 2PA cross-section values in water were obtained by an open aperture Z-scan measurement, and values were extremely large compared with those of monomeric porphyrins such as hematoporphyrin. These compounds were found to generate singlet oxygen efficiently upon one- as well as two-photon absorption as demonstrated by the time-resolved luminescence measurement at the characteristic band of singlet oxygen at 1270 nm and by using its scavenger. Photocytotoxicities for HeLa cancer cells were examined and found to be as high as those of hematoporphyrin, demonstrating that these compounds are potential candidates for 2PA-photodynamic therapy agents.

  2. Removal of chromium from aqueous solution by complexation-ultrafiltration using a water-soluble macroligand.

    Science.gov (United States)

    Aliane, A; Bounatiro, N; Cherif, A T; Akretche, D E

    2001-06-01

    A process for purifying waste waters containing heavy and toxic metal such as chromium has been studied. A batch complexation-ultrafiltration process was used to concentrate and recover chromium from sulphate solution. As the chromium ions are too small to be retained by the filter, they are first complexed with a water-soluble macroligand (polyethylene-imine). Factors affecting the rejection rate and permeate flux such as pH, concentration ligand, chloride and sulphate concentration, membrane pore size, applied pressure and extraction factor were investigated. Best operating conditions can be obtained in order to achieve high levels of removal (> 95%). Then, decomplexation is obtained so that metal can be separated from macroligand by a second ultrafiltration plant to reuse the macroligand.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Dumesic, James A.; Luterbacher, Jeremy S.

    2015-06-02

    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.

  5. A new approach on estimation of solubility and n-octanol/water partition coefficient for organohalogen compounds.

    Science.gov (United States)

    Gao, Shuo; Cao, Chenzhong

    2008-06-01

    The aqueous solubility (logW) and n-octanol/water partition coefficient (logP(OW)) are important properties for pharmacology, toxicology and medicinal chemistry. Based on an understanding of the dissolution process, the frontier orbital interaction model was suggested in the present paper to describe the solvent-solute interactions of organohalogen compounds and a general three-parameter model was proposed to predict the aqueous solubility and n-octanol/water partition coefficient for the organohalogen compounds containing nonhydrogen-binding interactions. The model has satisfactory prediction accuracy. Furthermore, every item in the model has a very explicit meaning, which should be helpful to understand the structure-solubility relationship and may be provide a new view on estimation of solubility.

  6. A New Approach on Estimation of Solubility and n-Octanol/ Water Partition Coefficient for Organohalogen Compounds

    Directory of Open Access Journals (Sweden)

    Chenzhong Cao

    2008-06-01

    Full Text Available The aqueous solubility (logW and n-octanol/water partition coefficient (logPOW are important properties for pharmacology, toxicology and medicinal chemistry. Based on an understanding of the dissolution process, the frontier orbital interaction model was suggested in the present paper to describe the solvent-solute interactions of organohalogen compounds and a general three-parameter model was proposed to predict the aqueous solubility and n-octanol/water partition coefficient for the organohalogen compounds containing nonhydrogen-binding interactions. The model has satisfactory prediction accuracy. Furthermore, every item in the model has a very explicit meaning, which should be helpful to understand the structure-solubility relationship and may be provide a new view on estimation of solubility.

  7. Soluble urokinase plasminogen activator receptor is in contrast to high-sensitive C-reactive-protein associated with coronary artery calcifications in healthy middle-aged subjects

    DEFF Research Database (Denmark)

    Sørensen, Mette Hjortdal; Gerke, Oke; Eugen-Olsen, Jesper;

    2014-01-01

    OBJECTIVE: The main objective of this study was to investigate the association between two markers of low-grade inflammation; soluble urokinase plasminogen activator receptor (suPAR) and high-sensitive C-reactive protein (hs-CRP); and coronary artery calcification (CAC) score detected by cardiac...... computed tomography (CT) scan. DESIGN: A cross sectional study of 1126 randomly sampled middle-aged men and women. METHODS: CAC score was measured by a non-contrast cardiac CT scan and total 10-year cardiovascular mortality risk was estimated using the Systematic Coronary Risk Evaluation (SCORE). Plasma...... samples were analysed for suPAR and hs-CRP. The association of suPAR and hs-CRP to CAC was evaluated by logistic regression analyses adjusting for categorised SCORE. The additive effect of suPAR to SCORE was evaluated by comparing area under curve (AUC) and net reclassification improvement (NRI). RESULTS...

  8. Current Trends in Self-Emulsifying Drug Delivery Systems (SEDDSs) to Enhance the Bioavailability of Poorly Water-Soluble Drugs.

    Science.gov (United States)

    Karwal, Rohit; Garg, Tarun; Rath, Goutam; Markandeywar, Tanmay S

    2016-01-01

    The main object of the self-emulsifying drug-delivery system (SEDDS) is oral bioavailability (BA) enhancement of a poorly water-soluble drug. Low aqueous solubility and low oral BA are major concerns for formulation scientists. As many drugs are lipophilic in nature, their lower solubility and dissolution are major drawbacks for their successful formulation into oral dosage forms. More than 60% of drugs have a lipophilic nature and exhibit poor aqueous solubility. Various strategies are reported in the literature to improve the solubility and enhance BA of lipophilic drugs, including the formation of a cyclodextrin complex, solid dispersions, and micronization. SEDDSs are ideally isotropic mixtures of drug, oil, surfactant, and/or cosurfactant. SEDDSs have gained increasing attention for enhancing oral BA and reducing drug dose. SEDDSs also provide an effective and excellent solution to the various issues related to the formulation of hydrophobic drugs that have limited solubility in gastrointestinal fluid. Our major focus of this review is to highlight the importance of SEDDSs in oral BA enhancement of poorly water-soluble drugs.

  9. Improved oral bioavailability of poorly water-soluble glimepiride by utilizing microemulsion technique

    Directory of Open Access Journals (Sweden)

    Li HY

    2016-08-01

    Full Text Available Haiying Li,1 Tingting Pan,1 Ying Cui,1 Xiaxia Li,1 Jiefang Gao,1 Wenzhi Yang,1 Shigang Shen2 1Key Laboratory of Pharmaceutical Quality Control of Hebei Province, College of Pharmacy, 2Key Laboratory of Analytical Science and Technology of Hebei Province, College of Chemistry and Environmental Science, Hebei University, Baoding, People’s Republic of China Abstract: The objective of this work was to prepare an oil/water glimepiride (GM microemulsion (ME for oral administration to improve its solubility and enhance its bioavailability. Based on a solubility study, pseudoternary phase diagrams, and Box–Behnken design, the oil/water GMME formulation was optimized and prepared. GMME was characterized by dynamic laser light scattering, zeta potential, transmission electron microscopy, and viscosity. The in vitro drug release, storage stability, pharmacodynamics, and pharmacokinetics of GMME were investigated. The optimized GMME was composed of Capryol 90 (oil, ­Cremophor RH40 (surfactant, and Transcutol (cosurfactant, and increased GM solubility up to 544.6±4.91 µg/mL. The GMME was spherical in shape. The particle size and its polydispersity index were 38.9±17.46 nm and 0.266±0.057, respectively. Meanwhile, the GMME was physicochemically stable at 4°C for at least 3 months. The short-term efficacy in diabetic mice provided the proof that blood glucose had a consistent and significant reduction at a dose of 375 µg/kg whether via IP injection or IG administration of GMME. Compared with the glimepiride suspensions or glimepiride-meglumine complex solution, the pharmacokinetics of GMME in Wistar rats via IG administration exhibited higher plasma drug concentration, larger area under the curve, and more enhanced oral bioavailability. There was a good correlation of GMME between the in vitro release values and the in vivo oral absorption. ME could be an effective oral drug delivery system to improve bioavailability of GM. Keywords: glimepiride

  10. 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

  11. Phase transfer of hydrophobic QDs for water-soluble and biocompatible nature through silanization

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ping, E-mail: mse_yangp@ujn.edu.cn [School of Material Science and Engineering, University of Jinan, Jinan 250022 (China); Zhou, Guangjun [State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China)

    2011-12-15

    Graphical abstract: A facile and novel method has been developed for creating water-soluble and biocompatible CdSe/ZnS quantum dots with a small hydrodynamic diameter (less than 10 nm) via silanization. Highlights: Black-Right-Pointing-Pointer A facile and novel method has been developed for creating water-soluble and biocompatible CdSe/ZnS quantum dots (QDs) with a small hydrodynamic diameter (less than 10 nm). Black-Right-Pointing-Pointer The control of ligand exchange plays an important role to retain high fluorescence quantum yields. Black-Right-Pointing-Pointer The functional SiO{sub 2}-coated QDs were conjugated with immunoglobin G antibody by using biotin-streptavidin as linkers. Black-Right-Pointing-Pointer The QD phase transfer by silanization is a well-established method for generating biocompatible QDs. -- Abstract: A novel method has been developed for creating water-soluble and biocompatible CdSe/ZnS quantum dots (QDs) with a small hydrodynamic diameter (less than 10 nm). The silanization of the QDs was carried out by using partially hydrolyzed tetraethyl orthosilicate (TEOS) to replace organic ammine or tri-n-octylphosphine oxide on the surface of the QDs. The partially hydrolyzed 3-mercaptopropyltrimethoxysilane attached to the hydrolyzed TEOS layer on the QDs prevented the QDs from agglomeration when the QDs were transferred into water. The functional SiO{sub 2}-coated QDs were conjugated with immunoglobin G antibody by using biotin-streptavidin as linkers. The SiO{sub 2}-coated QDs exhibited the same absorption and photoluminescence (PL) spectra as those of initial QDs in organic solvents. The SiO{sub 2}-coated QDs preserved PL intensities, is colloidally stable over a wide pH range (pH 6-11). Because the mean diameter of amphiphilic polymer-coated QDs was almost 2 times of that of functional SiO{sub 2}-coated QDs, the QD phase transfer by silanization is a well-established method for generating biocompatible QDs.

  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 free radical scavenging activity of Ganoderma lucidum K from Godean (IC50 11.5 ± 0.29 mg/mL) higher than Kaliurang (IC50 14.4 ± 0.27%).

  13. Response of antioxidase in viscera of Pagrosuma Major larvae to water soluble fraction of hydrocarbons in No.0 diesel oil

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Pagrosomus major larvae were exposed to thewater-soluble fraction of hydrocarbon in No.0 diesel oil(corresponding to No. 2 fuel oil) at concentrations of 0, 0.l7,l.22 and 8.82 mg/L for up to l5 days. Larvae were sampled on days9 and l5 of the experiment. Supernatants of viscera tissueextractions were assayed for biochemical response in terms ofoxidative stress-superoxide dismutase(SOD), activity ofselenium-dependant glutathione peroxidase(Se-GPx) and catalase(Ca), and the concentration of reduced glutathione(GSH). On day 9of exposure, statistically significant dose-related increases inSe-GPx and SOD activity, and GSH concentration were observed in allcases except for Se-GPx activity under the highest dosage of hydrocarbon. However, on day l5 of exposure, a similar dose-relatedresponse was only observed for Se-GPx activity. GSH concentrationdecreased and SOD activity showed no statistical difference ascompared to controls. However, a significant decrease in comparedto day 9 Se-GPx activity and GSH concentration, in contrast toincreased SOD activity at day 15 as indicates an acceleratedaccumulation of H2O2 and potential oxidative damage under long termexposure of larvae to hydrocarbons. No statistical changes wereobserved in Ca activity throughout the experiment, possibly owingto the high efficiency of Se-GPx.A recovery experiment was performed on indicating that theresponse of antioxidants measured tending to return to theircontrol levels. These results prove the function of the antioxidantdefense system of the larvae to the water-soluble fraction ofhydrocarbons in No. 0 diesel oil.

  14. Effects of solvent evaporation on water sorption/solubility and nanoleakage of adhesive systems

    Directory of Open Access Journals (Sweden)

    Talita Baumgratz Cachapuz CHIMELI

    2014-07-01

    Full Text Available Objective: To evaluate the influence of solvent evaporation in the kinetics of water diffusion (water sorption-WS, solubility-SL, and net water uptake and nanoleakage of adhesive systems. Material and Methods: Disk-shaped specimens (5.0 mm in diameter x 0.8 mm in thickness were produced (N=48 using the adhesives: Clearfil S3 Bond (CS3/Kuraray, Clearfil SE Bond - control group (CSE/Kuraray, Optibond Solo Plus (OS/Kerr and Scotchbond Universal Adhesive (SBU/3M ESPE. The solvents were either evaporated for 30 s or not evaporated (N=24/per group, and then photoactivated for 80 s (550 mW/cm2. After desiccation, the specimens were weighed and stored in distilled water (N=12 or mineral oil (N=12 to evaluate the water diffusion over a 7-day period. Net water uptake (% was also calculated as the sum of WS and SL. Data were submitted to 3-way ANOVA/Tukey's test (α=5%. The nanoleakage expression in three additional specimens per group was also evaluated after ammoniacal silver impregnation after 7 days of water storage under SEM. Results: Statistical analysis revealed that only the factor "adhesive" was significant (p<0.05. Solvent evaporation had no influence in the WS and SL of the adhesives. CSE (control presented significantly lower net uptake (5.4%. The nanoleakage was enhanced by the presence of solvent in the adhesives. Conclusions: Although the evaporation has no effect in the kinetics of water diffusion, the nanoleakage expression of the adhesives tested increases when the solvents are not evaporated.

  15. 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

  16. 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...

  17. Effects of Water Deficit and Chitosan Spraying on Osmotic Adjustment and Soluble Protein of Cultivars Castor Bean (Ricinus communis L.

    Directory of Open Access Journals (Sweden)

    Karimi Sara

    2012-08-01

    Full Text Available The present study was aimed investigating the effect of water deficit and chitosan spraying on osmotic adjustment and soluble protein of cultivars castor bean under field condition. experiment was carried out as a split factorial based on randomized complete block design with three replications. The results showed that water deficit caused increase a significant (P<0.05 in the concentration of sugars and proline content in the leaves of castor bean. The most amount of total soluble sugars obtain of Levels (D2: Water deficit in beginning of flowering stage, D3: Water deficit in beginning of seedling stage, 0.042% and minimum amount related to treatment control (D1: complete Irrigation , 0.014% and maximum proline content related to (D3: water deficit in beginning seedling stage and minimum proline content related to (D1: complete Irrigation. Also water Deficit caused decrease a significant (P<0.05 in Protein content. The mean comparison shows that maximum amount Protein related to (D1: complete Irrigation, 26.79% and the minimum amount Protein obtain from (D2: Water deficit in beginning of Flowering stage, 21.04%. also a had cultivars between different a significant (P<0.01 of total soluble sugars. Chitosan spraying no had a significant in osmotic Adjustment and soluble protein. The accumulation of the osmolytes can help the castor bean plant to maintain the cell turgor and the structural integrity of membranes. castor bean herb is drought tolerant, the experimental our, cultivars between no had a significant different of proline and protein content. But, cultivars between had a significant different of total soluble sugars, the result show that cultivar Ahvaz local the most amount of total soluble sugars. therefore suggested that Ahvaz Local cultivar in water deficit condition rate of other cultivar toleranter, we can be with attention Damghan Climate condition, there Cultivate Ahvaz local cultivar.

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

    Science.gov (United States)

    Zhu, Zi-Chun; Wu, Qing-Sheng; Chen, Ping; Yang, Xiao-Hong

    2011-10-01

    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 AgNO3 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.

  19. Hydroxypropyl cellulose stabilizes amorphous solid dispersions of the poorly water soluble drug felodipine.

    Science.gov (United States)

    Sarode, Ashish L; Malekar, Swapnil A; Cote, Catherine; Worthen, David R

    2014-11-04

    Overcoming the low oral bioavailability of many drugs due to their poor aqueous solubility is one of the major challenges in the pharmaceutical industry. The production of amorphous solid dispersions (ASDs) of these drugs using hydrophilic polymers may significantly improve their solubility. However, their storage stability and the stability of their supersaturated solutions in the gastrointestinal tract upon administration are unsolved problems. We have investigated the potential of a low viscosity grade of a cellulosic polymer, hydroxypropyl cellulose (HPC-SSL), and compared it with a commonly used vinyl polymer, polyvinylpyrrolidone vinyl acetate (PVP-VA), for stabilizing the ASDs of a poorly water soluble drug, felodipine. The ASDs were produced using hot melt mixing and stored under standard and accelerated stability conditions. The ASDs were characterized using differential scanning calorimetry, powder X-ray diffraction, and Fourier transform infrared spectroscopy. Drug dissolution and partitioning rates were evaluated using single- and biphasic dissolution studies. The ASDs displayed superior drug dissolution and partitioning as compared to the pure crystalline drug, which might be attributed to the formation of a drug-polymer molecular dispersion, amorphous conversion of the drug, and drug-polymer hydrogen bonding interactions. Late phase separation and early re-crystallization occurred at lower and higher storage temperatures, respectively, for HPC-SSL ASDs, whereas early phase separation, even at low storage temperatures, was noted for PVP-VA ASDs. Consequently, the partitioning rates for ASDs dispersed in HPC-SSL were greater than those of PVP-VA at lower and room temperature storage, whereas the performance of both of the ASDs was similar when stored at higher temperatures.

  20. Antioxidant and nitric oxide synthase activation properties of water soluble polysaccharides from Pleurotus florida

    Directory of Open Access Journals (Sweden)

    Subarna Saha

    2013-01-01

    Full Text Available Context: Cellular damage caused by reactive oxygen species has been implicated in several diseases, and, at the same time, nitric oxide is recognized as an important messenger molecule for several pathophysiological conditions. Hence, a novel antioxidant and nitric oxide synthase (NOS activator from natural sources have significant importance in human health. Aims: The present study was conducted to evaluate the free radical-scavenging activity and NOS activation properties of water-soluble crude polysaccharide (Floridan from Pleurotus florida. Materials and Methods: Crude polysaccharide was precipitated from hot water extract of P. florida, and their physicochemical parameters were determined. Then, α and β glucan were estimated using mushroom and yeast β glucan assay kit and Fourier transform infrared spectroscopy (FT-IR. Floridan was analyzed for their free radical scavenging activity in different test systems, namely hydroxyl and superoxide radical scavenging activity, ferrous ion chelating ability, determination of reducing power and inhibition of lipid peroxidation. Floridan was also tested for NOS activation using oxyhaemoglobin method. Statistical Analysis: The results were statistically analyzed using the Student′s t-test. Results: Results showed that Floridan was rich in water-soluble β glucan with very low amount of protein and phenols. The EC 50 for hydroxyl and superoxide radical-scavenging activity were 140 and 320 μg/ml, respectively, 450 μg/ml for chelating ability, 300 μg/ml for inhibition of lipid peroxidation and 2 mg/ml for reducing power. Floridan also increased nitric oxide production significantly. Conclusions: The present results revealed that this mushroom polysaccharide may be utilized as a promising dietary supplement to combat several killer diseases.

  1. Solubility of water in lunar basalt at low pH2O

    Science.gov (United States)

    Newcombe, M. E.; Brett, A.; Beckett, J. R.; Baker, M. B.; Newman, S.; Guan, Y.; Eiler, J. M.; Stolper, E. M.

    2017-03-01

    We report the solubility of water in Apollo 15 basaltic "Yellow Glass" and an iron-free basaltic analog composition at 1 atm and 1350 °C. We equilibrated melts in a 1-atm furnace with flowing H2/CO2 gas mixtures that spanned ∼8 orders of magnitude in fO2 (from three orders of magnitude more reducing than the iron-wüstite buffer, IW-3.0, to IW+4.8) and ∼4 orders of magnitude in pH2/pH2O (from 0.003 to 24). Based on Fourier transform infrared spectroscopy (FTIR), our quenched experimental glasses contain 69-425 ppm total water (by weight). Our results demonstrate that under the conditions of our experiments: (1) hydroxyl is the only H-bearing species detected by FTIR; (2) the solubility of water is proportional to the square root of pH2O in the furnace atmosphere and is independent of fO2 and pH2/pH2O; (3) the solubility of water is very similar in both melt compositions; (4) the concentration of H2 in our iron-free experiments is ppm, even at oxygen fugacities as low as IW-2.3 and pH2/pH2O as high as 11; (5) Secondary ion mass spectrometry (SIMS) analyses of water in iron-rich glasses equilibrated under variable fO2 conditions may be strongly influenced by matrix effects, even when the concentration of water in the glasses is low; and (6) Our results can be used to constrain the entrapment pressure of lunar melt inclusions and the partial pressures of water and molecular hydrogen in the carrier gas of the lunar pyroclastic glass beads. We find that the most water-rich melt inclusion of Hauri et al. (2011) would be in equilibrium with a vapor with pH2O ∼ 3 bar and pH2 ∼ 8 bar. We constrain the partial pressures of water and molecular hydrogen in the carrier gas of the lunar pyroclastic glass beads to be 0.0005 bar and 0.0011 bar respectively. We calculate that batch degassing of lunar magmas containing initial volatile contents of 1200 ppm H2O (dissolved primarily as hydroxyl) and 4-64 ppm C would produce enough vapor to reach the critical vapor volume

  2. Wettability and surface chemistry of crystalline and amorphous forms of a poorly water soluble drug.

    Science.gov (United States)

    Puri, Vibha; Dantuluri, Ajay K; Kumar, Mahesh; Karar, N; Bansal, Arvind K

    2010-05-12

    The present study compares energetics of wetting behavior of crystalline and amorphous forms of a poorly water soluble drug, celecoxib (CLB) and attempts to correlate it to their surface molecular environment. Wettability and surface free energy were determined using sessile drop contact angle technique and water vapor sorption energetics was measured by adsorption calorimetry. The surface chemistry was elucidated by X-ray photoelectron spectroscopy (XPS) and crystallographic evaluation. The two solid forms displayed distinctly different wetting with various probe liquids and in vitro dissolution media. The crystalline form surface primarily exhibited dispersive surface energy (47.3mJ/m(2)), while the amorphous form had a slightly reduced dispersive (45.2mJ/m(2)) and a small additional polar (4.8mJ/m(2)) surface energy. Calorimetric measurements, revealed the amorphous form to possess a noticeably high differential heat of absorption, suggesting hydrogen bond interactions between its polar energetic sites and water molecules. Conversely, the crystalline CLB form was found to be inert to water vapor sorption. The relatively higher surface polarity of the amorphous form could be linked to its greater oxygen-to-fluorine surface concentration ratio of 1.27 (cf. 0.62 for crystalline CLB), as determined by XPS. The crystallographic studies of the preferred cleavage plane (020) of crystalline CLB further supported its higher hydrophobicity. In conclusion, the crystalline and amorphous forms of CLB exhibited disparate surface milieu, which in turn can have implications on the surface mediated events.

  3. Solvent de-binding of water-soluble binder in powder injection moulding

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The solvent debinding of water-soluble binder in powder injection moulding (MIM) was investigated systematically, including the effects of solvent types, temperature and the thickness of green parts on the solvent debinding rate. After studying the debinding of a green part with a thickness of 4.26mm, it was found that, the debinding rate of polyethylene glycol(PEG) in water and alcohol was high initially, and then decreased; however, it would increase with temperature increasing. At room temperature, the dissolution rate of PEG in water was higher than that in alcohol, but the latter would be much faster with temperature increasing because the debinding activation energy in alcohol was 51.44 kJ· mol- 1 · K- 1, much higher than 24.23 kJ·mol 1· K- 1 in water. With a green part thickness larger than 4.26 mm, the debinding was controlled by diffusion; but with that smaller than 2.36 mm, the debinding was controlled by both dissolution and diffusion.

  4. Effect of Thiobacillus, sulfur, and vermicompost on the water-soluble phosphorus of hard rock phosphate.

    Science.gov (United States)

    Aria, Marzieh Mohammady; Lakzian, Amir; Haghnia, Gholam Hosain; Berenji, Ali Reza; Besharati, Hosein; Fotovat, Amir

    2010-01-01

    Sulfur, organic matter, and inoculation with sulfur-oxidizing bacteria are considered as amendments to increase the availability of phosphorus from rock phosphate. The present study was conducted to evaluate the best combination of sulfur, vermicompost, and Thiobacillus thiooxidans inoculation with rock phosphate from Yazd province for direct application to agricultural lands in Iran. For such study, an experiment was carried out in a completely randomized design with factorial arrangement: Elemental sulfur originated from Sarakhs mine at three rates, 0% (S1), 10% (S2), 20% (S3), vermicompost at two rates, 0% (V1), 15% (V2), and inoculation without (B1) and with (B2) T. thiooxidans, in three replications. The results showed that water-soluble phosphorus (WSP) content was significantly higher in inoculated treatments compared to non-inoculated treatments. Sulfur had a significant effect on WSP. The highest solubility rate of rock phosphate was obtained in 20% of sulfur (S3) treatments and it was 2.4 times more than S1 treatments. Vermicompost also had a significant and positive effect on WSP of rock phosphate dissolution. The results also revealed that the highest concentration of WSP, sulfate and the lowest pH were obtained in treatments with 20% sulfur, 15% vermicompost inoculated with T. thiooxidans (B2S3V2).

  5. Water Soluble Aluminum Paste Using Polyvinyl Alcohol for Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Abdullah Uzum

    2015-01-01

    Full Text Available Screen-printing aluminum is still dominantly used in the solar cell fabrication process. Ethyl cellulose is one of the main contents of screen-printing pastes that require dichloromethane for its cleaning process, a substance renowned for being extremely toxic and threatening to the human body. Developing environmental friendly aluminum pastes is essential in order to provide an alternative to the commercial pastes. In this work, new, nontoxic polyvinyl alcohol-based aluminum pastes are introduced. Polyvinyl alcohol was used as a soluble polymer that can be synthesized without saponification and that is also soluble in water. Three different pastes were developed using different recipes including many aluminum particle sizes varying from 3.0 to 45 μm, aluminum oxide with particle sizes between 35 and 50 μm, and acetic acid. Evaluation of the pastes was carried out by Scanning Electron Microscope (SEM image analysis, sheet resistance measurements, and fabricating silicon solar cells using each paste. Solar cells with 15.6% efficiency were fabricated by nonvacuum processing on CZ-Si p-type wafers using developed aluminum pastes on the back side.

  6. Water-soluble BODIPY-based fluorescent probe for mitochondrial imaging (Conference Presentation)

    Science.gov (United States)

    Sui, Binglin; Tang, Simon; Woodward, Adam W.; Kim, Bosung; Belfield, Kevin D.

    2016-03-01

    A new mitochondrial targeting fluorescent probe is designed, synthesized, characterized, and investigated. The probe is composed of three moieties, a BODIPY platform working as the fluorophore, two triphenylphosphonium (TPP) groups serving as mitochondrial targeting moiety, and two long highly hydrophilic polyethylene glycol (PEG) chains to increase its water solubility and reduce its cytotoxicity. As a mitochondria-selective fluorescent probe, the probe exhibits a series of desirable advantages compared with other reported fluorescent mitochondrial probes. It is readily soluble in aqueous media and emits very strong fluorescence. Photophysical determination experiments show that the photophysical properties of the probe are independent of solvent polarity and it has high quantum yield in various solvents examined. The probe also has good photostability and pH insensitivity over a broad pH range. Results obtained from cell viability tests indicate that the cytotoxicity of the probe is very low. Confocal fluorescence microscopy colocalization experiments reveal that this probe possesses excellent mitochondrial targeting ability and it is suitable for imaging mitochondria in living cells.

  7. Relationships between Different Preparations of Cotton Hollow Yarn and Water Soluble PVA Extraction

    Institute of Scientific and Technical Information of China (English)

    MA Hui-ying; XIA Zhao-peng

    2006-01-01

    In this paper cotton hollow yarns were obtained from the core spun yarns which were produced on a little modified conventional experiment ring frame with water soluble staple PVA yarn as the core. For comparison, yarns with same linear densities, same twists of the sheath, different linear densities, different twist directions of the core were prepared. The results show that the tensile strengths of the hollow yarns decrease first, then increase and decrease again, at last the tensile strength trends to reach a steady state with the soluble PVA core extraction proceeding. And when the sheath linear densities of the core spun yarns are constant, their twist and twist direction are same as that of the core it will be easier to remove the core of the yarn with a higher core size. When the linear densities of the sheath and the core are all constant, the twists of them are same,it will be easier to remove the core of the yarn with a different twist direction of core to the sheath.

  8. pKa and solubility of drugs in water, ethanol, and 1-octanol.

    Science.gov (United States)

    Domańska, Urszula; Pobudkowska, Aneta; Pelczarska, Aleksandra; Gierycz, Paweł

    2009-07-02

    Dissociation constants and corresponding pK(a) values of five drugs were obtained with the Bates-Schwarzenbach method using a Perkin-Elmer Lambda 35 UV/vis spectrophotometer at temperature 298.15 K in the buffer solutions. Atropine, promethazine hydrochloride, ibuprofen, flurbiprofen, and meclofenamic acid sodium salt exhibited pK(a) values of 10.3, 6.47, 5.38, 4.50, and 4.39, respectively. The equilibrium mole fraction solubilities of six drugs were measured in a range of temperatures from 240 to 340 K in three important solvents for drugs: water, ethanol, and 1-octanol using the dynamic method. The basic thermal properties of pure drugs, i.e., melting and glass-transition temperatures, as well as the enthalpy of melting and the molar heat capacity at glass transition (at constant pressure) have been measured with the differential scanning microcalorimetry technique (DSC). Molar volumes have been calculated with the Barton group contribution method. The experimental solubility data have been correlated by means of three commonly known G(E) equations: the Wilson, NRTL, and UNIQUAC, with the assumption that the systems studied here have revealed simple eutectic mixtures. As a measure of goodness of correlation, the root-mean-square deviations of temperature have been used. The activity coefficients of the drugs in saturated solutions for each correlated binary mixture were calculated from the experimental data.

  9. INFLUENCE OF WATER-SOLUBLE COMPOUNDS OF RESTORED SULFUR ONTO TOXIC PROPERTIES OF NATURAL AND WASTE WATERS

    Directory of Open Access Journals (Sweden)

    Frog Boris Nikolaevich

    2012-10-01

    Full Text Available Whenever environmental pollution by sulphur compounds is under discussion, the latter contemplate those compounds that may be subjected to consideration through the employment of methods of analytical control. First of all, sulphates and volatile compounds of partially or completely restored sulphur, such as SO2, H2S, methyl sulphur compounds (merkaptans, dimethyl sulphide, dimethyl disulphide and others may be subjected to control. Elementary sulphur that is contained in the water is difficult to analyze. At the same time, an extensive group of water-soluble compounds of restored sulphur is not considered by numerous nature protection organizations. As a rule, they do not possess distinct analytical properties. The latter include any organic and inorganic thio-acids and their combinations with ions of transitive metals, in particular, with ions of monovalent copper. Microcolloidal (nano- particles of FeS may also be included into this group of compounds. The objective of the article is to generate the awareness of those compounds of reduced sulphur that are out of control. By virtue of this article, the authors apply to specialists in water treatment, water conditioning and water quality regulation.

  10. 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

  11. An investigation on dispersion and stability of water-soluble fullerenol (C60OH) in water via UV-Visible spectroscopy

    Science.gov (United States)

    Najafi, Abolhassan

    2017-02-01

    An investigation on dispersion, stability, and agglomeration of water-soluble fullerenol in water was studied via UV-Vis spectroscopy. The results showed that the dispersion quality and stability of water-soluble fullerenol commenced decreasing after 150 h (more than six days) of solution preparation time. Furthermore, increasing the fullerenol concentration in water (Cfullerenol) showed promotion of the agglomeration in lower residence time. Considering the results of DLS and HRTEM micrographs, an average particle size of the fullerenol in the solution was measured to be ∼150 nm after a residence of 2 months highlighting its high agglomeration tendency even at low concentration.

  12. Método extendido de Hildebrand en la predicción de la solubilidad del ketoprofeno en mezclas cosolventes etanol + agua Extended Hildebrand solubility approach in the estimation of ketoprofen solubility in ethanol + water cosolvent mixtures

    Directory of Open Access Journals (Sweden)

    Mauricio Gantiva

    2010-01-01

    Full Text Available Extended Hildebrand Solubility Approach (EHSA developed by Martin et al. was applied to evaluate the solubility of ketoprofen (KTP in ethanol + water cosolvent mixtures at 298.15 K. Calculated values of molar volume and solubility parameter for KTP were used. A good predictive capacity of EHSA was found by using a regular polynomial model in order five to correlate the W interaction parameter and the solubility parameters of cosolvent mixtures (δmix. Nevertheless, the deviations obtained in the estimated solubilities with respect to the experimental solubilities were on the same order like those obtained directly by means of an empiric regression of the logarithmic experimental solubilities as a function of δmix values.

  13. Enhanced Wettability Modification and CO2 Solubility Effect by Carbonated Low Salinity Water Injection in Carbonate Reservoirs

    Directory of Open Access Journals (Sweden)

    Ji Ho Lee

    2017-01-01

    Full Text Available Carbonated water injection (CWI induces oil swelling and viscosity reduction. Another advantage of this technique is that CO2 can be stored via solubility trapping. The CO2 solubility of brine is a key factor that determines the extent of these effects. The solubility is sensitive to pressure, temperature, and salinity. The salting-out phenomenon makes low saline brine a favorable condition for solubilizing CO2 into brine, thus enabling the brine to deliver more CO2 into reservoirs. In addition, low saline water injection (LSWI can modify wettability and enhance oil recovery in carbonate reservoirs. The high CO2 solubility potential and wettability modification effect motivate the deployment of hybrid carbonated low salinity water injection (CLSWI. Reliable evaluation should consider geochemical reactions, which determine CO2 solubility and wettability modification, in brine/oil/rock systems. In this study, CLSWI was modeled with geochemical reactions, and oil production and CO2 storage were evaluated. In core and pilot systems, CLSWI increased oil recovery by up to 9% and 15%, respectively, and CO2 storage until oil recovery by up to 24% and 45%, respectively, compared to CWI. The CLSWI also improved injectivity by up to 31% in a pilot system. This study demonstrates that CLSWI is a promising water-based hybrid EOR (enhanced oil recovery.

  14. Application of mineral bed materials during fast pyrolysis of rice husk to improve water-soluble organics production.

    Science.gov (United States)

    Li, R; Zhong, Z P; Jin, B S; Zheng, A J

    2012-09-01

    Fast pyrolysis of rice husk was performed in a spout-fluid bed to produce water-soluble organics. The effects of mineral bed materials (red brick, calcite, limestone, and dolomite) on yield and quality of organics were evaluated with the help of principal component analysis (PCA). Compared to quartz sand, red brick, limestone, and dolomite increased the yield of the water-soluble organics by 6-55% and the heating value by 16-19%. The relative content of acetic acid was reduced by 23-43% with calcite, limestone and dolomite when compared with quartz sand. The results from PCA showed all minerals enhanced the ring-opening reactions of cellulose into furans and carbonyl compounds rather than into monomeric sugars. Moreover, calcite, limestone, and dolomite displayed the ability to catalyze the degradation of heavy compounds and the demethoxylation reaction of guaiacols into phenols. Minerals, especially limestone and dolomite, were beneficial to the production of water-soluble organics.

  15. Determination of the solubility of low volatility liquid organic compounds in water using volatile-tracer assisted headspace gas chromatography.

    Science.gov (United States)

    Zhang, Shu-Xin; Chai, Xin-Sheng; Barnes, Donald G

    2016-02-26

    This study reports a new headspace gas chromatographic method (HS-GC) for the determination of water solubility of low volatility liquid organic compounds (LVLOs). The HS-GC analysis was performed on a set of aqueous solutions containing a range of concentrations of toluene-spiked (as a tracer) LVLOs, from under-saturation to over-saturation. A plot of the toluene tracer GC signal vs. the concentration of the LVLO results in two lines of different slopes that intersect at the concentration corresponding to the compound's solubility in water. The results showed that the HS-GC method has good precision (RSD solubility of LVLOs at elevated temperatures. This approach should be of special interest to those concerned about the impact of the presence of low-volatility organic liquids in waters of environmental and biological systems.

  16. Au nanorods modulated NIR fluorescence and singlet oxygen generation of water soluble dendritic zinc phthalocyanine.

    Science.gov (United States)

    Zhou, Xuefei; He, Xiaohong; Wei, Shiliang; Jia, Kun; Liu, Xiaobo

    2016-11-15

    A novel cyano-terminated zinc phthalocyanine (ZnPc-CN) exhibiting visible near infrared (vis-NIR) emitting around 690nm in N,N-dimethylformamide (DMF) solvent has been synthesized. Furthermore, the peripheral cyano groups of newly synthesized zinc phthalocyanine were hydrolyzed in strong basic solution, leading to water soluble carboxylated zinc phthalocyanine (ZnPc-COOH) with completely quenched fluorescence in aqueous solution. Interestingly, we found that the NIR fluorescence of aqueous ZnPc-COOH was dramatically recovered in the presence of gold nanorods (Au NR), which was due to the alternation of ZnPc-COOH molecules self-assembling via electrostatic interaction between cetyltrimethylammonium bromide (CTAB) on the surface of Au NR and peripheral carboxyl of ZnPc-COOH. In addition, ZnPc-COOH/Au NR conjugates demonstrated an improved singlet oxygen generation, which could be served as potential bioimaging probe and photosensitizer for photodynamic therapy.

  17. Amino acids as co-amorphous stabilizers for poorly water-soluble drugs - Part 2

    DEFF Research Database (Denmark)

    Löbmann, K.; Laitinen, R.; Strachan, C.

    2013-01-01

    The formation of co-amorphous drug-drug mixtures has proved to be a powerful approach to stabilize the amorphous form and at the same time increase the dissolution of poorly water-soluble drugs. Molecular interactions in these co-amorphous formulations can play a crucial role in stabilization...... and dissolution enhancement. In this regard, Fourier-transform infrared spectroscopy (FTIR) is a valuable tool to analyze the molecular near range order of the compounds in the co-amorphous mixtures. In this study, several co-amorphous drugs - low molecular weight excipient blends - have been analyzed with FTIR...... spectroscopy. Molecular interactions of the drugs carbamazepine and indomethacin with the amino acids arginine, phenylalanine, and tryptophan were investigated. The amino acids were chosen from the biological target site of both drugs and prepared as co-amorphous formulations together with the drugs...

  18. 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.

  19. PREPARATION AND PHOTOSENSITIVITY OF WATER SOLUBLE PHENOLIC RESINS CONTAINING ACRYLOYL AND QUATERNARY AMMONIUM CHLORIDE GROUPS

    Institute of Scientific and Technical Information of China (English)

    Xiao-ming Tan; Hong-quan Xie; Nai-yu Huang

    2002-01-01

    New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solution of triethylamine hydrochloride successively. The second reaction needs no phase transfer catalyst to accelerate, since the product formed can act as a phase transfer catalyst. The prepolymer obtained contains both photocrosslinkable acrylate groups and hydrophilic quaternary ammonium salt groups. Optimum conditions for these reactions were studied. The photosensitivity of the prepolymer was also investigated. The effects of different photoinitiators, different crosslinkable diluent monomers and amine accelerator on the photosensitivity of the prepolymer were compared. The photoinitiator of hydrogen abstraction type is still effective without using amine or alcohol as accelerator, because the prepolymer contains α H beside the OH groups formed in the ring-opening reactions.

  20. LiFePO 4 water-soluble binder electrode for Li-ion batteries

    Science.gov (United States)

    Guerfi, A.; Kaneko, M.; Petitclerc, M.; Mori, M.; Zaghib, K.

    A new water-soluble elastomer from ZEON Corp. was evaluated as binder with LiFePO 4 cathode material in Li-ion batteries. The mechanical characteristic of this cathode was compared to that with PVdF-based cathode binder. The elastomer-based cathode shows high flexibility with good adhesion. The electrochemical performance was also evaluated and compared to PVdF-based cathodes at 25 and at 60 °C. A lower irreversible capacity loss was obtained with the elastomer-based cathode, however, aging at 60 °C shows a comparable cycle life to that observed with PVdF-based cathodes. The LiFePO 4-WSB at high rate shows a good performance with 120 mAh g -1 at 10 C rate at 60 °C.

  1. LiFePO{sub 4} water-soluble binder electrode for Li-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Guerfi, A.; Petitclerc, M.; Zaghib, K. [Institut de Recherche d' Hydro-Quebec, 1800 Lionel-Boulet, Varennes, Que. J3X 1S1 (Canada); Kaneko, M.; Mori, M. [ZEON Corporation, R and D Center, 1-2-1 Yako, Kawasaki, Kanagawa 210-9507 (Japan)

    2007-01-01

    A new water-soluble elastomer from ZEON Corp. was evaluated as binder with LiFePO{sub 4} cathode material in Li-ion batteries. The mechanical characteristic of this cathode was compared to that with PVdF-based cathode binder. The elastomer-based cathode shows high flexibility with good adhesion. The electrochemical performance was also evaluated and compared to PVdF-based cathodes at 25 and at 60{sup o}C. A lower irreversible capacity loss was obtained with the elastomer-based cathode, however, aging at 60{sup o}C shows a comparable cycle life to that observed with PVdF-based cathodes. The LiFePO{sub 4}-WSB at high rate shows a good performance with 120mAhg{sup -1} at 10C rate at 60{sup o}C. (author)

  2. In Vitro Selection of Optimal DNA Substrates for Ligation by a Water-Soluble Carbodiimide

    Science.gov (United States)

    Harada, Kazuo; Orgel, Leslie E.

    1994-01-01

    We have used in vitro selection to investigate the sequence requirements for efficient template-directed ligation of oligonucleotides at 0 deg C using a water-soluble carbodiimide as condensing agent. We find that only 2 bp at each side of the ligation junction are needed. We also studied chemical ligation of substrate ensembles that we have previously selected as optimal by RNA ligase or by DNA ligase. As anticipated, we find that substrates selected with DNA ligase ligate efficiently with a chemical ligating agent, and vice versa. Substrates selected using RNA ligase are not ligated by the chemical condensing agent and vice versa. The implications of these results for prebiotic chemistry are discussed.

  3. Nanonization of poorly water-soluble drug clobetasone butyrate by using femtosecond laser

    Science.gov (United States)

    Pan, Sunqiang; Takebe, Gen; Suzuki, Masumi; Takamoto, Hisayoshi; Ge, Jianhong; Liu, Chong; Hiramatsu, Mitsuo

    2014-02-01

    Nanonization, which involves the formation of the drug with nanometer particle size, is an effective method to improve the dissolution rate and bioavailability of poorly water-soluble drugs. A pulsewidth-tunable femtosecond laser was used to produce nanoparticles of clobetasone butyrate using poloxamer 188 as stabilizing agent. The effects of temperature and pulsewidth on the particle size and concentration were studied for the first time. The particle size and drug concentration dependence on the laser intensity and irradiation time were also investigated. Permeability test releaved that laser nanonization improved the drug permeability across Caco-2 cell monolayer. This laser nanonization method has a great potential to be used for new drug development.

  4. Modeling the formation of soluble microbial products (SMP) in drinking water biofiltration

    Institute of Scientific and Technical Information of China (English)

    Yu Xin; Ye Lin; Wei Gu

    2008-01-01

    Both a theoretical and an empirical model were developed for predicting the formation of soluble microbial products (SMP) during drinking water biofiltration. Four pilot-scale biofilters with ceramsite as the medium were fed with different acetate loadings for the determination of SMP formation. Using numerically simulated and measured parameters, the theoretical model was developed according to the substrate and biomass balance. The results of this model matched the measured data better for higher SMP formation but did not fit well when SMP formation was lower. In order to better simulate the reality and overcome the difficulties of measuring the kinetic parameters, a simpler empirical model was also developed. In this model, SMP formation was expressed as a function of fed organic loadings and the depth of the medium, and a much better fit was obtained.

  5. Automatic carbon dioxide-methane gas sensor based on the solubility of gases in water.

    Science.gov (United States)

    Cadena-Pereda, Raúl O; Rivera-Muñoz, Eric M; Herrera-Ruiz, Gilberto; Gomez-Melendez, Domingo J; Anaya-Rivera, Ely K

    2012-01-01

    Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0-100%. The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA) platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

  6. Prediction of oxygen solubility in pure water and brines up to high temperatures and pressures

    Science.gov (United States)

    GENG, Ming; DUAN, Zhenhao

    2010-10-01

    A thermodynamic model is presented to calculate the oxygen solubility in pure water (273-600 K, 0-200 bar) and natural brines containing Na +, K +, Ca 2+, Mg 2+, Cl -, SO 42-, over a wide range of temperature, pressure and ionic strength with or close to experimental accuracy. This model is based on an accurate equation of state to calculate vapor phase chemical potential and a specific particle interaction model for liquid phase chemical potential. With this approach, the model can not only reproduce the existing experimental data, but also extrapolate beyond the data range from simple aqueous salt system to complicated brine systems including seawater. Compared with previous models, this model covers much wider temperature and pressure space in variable composition brine systems. A program for this model can be downloaded from the website: http://www.geochem-model.org.

  7. Automatic Carbon Dioxide-Methane Gas Sensor Based on the Solubility of Gases in Water

    Directory of Open Access Journals (Sweden)

    Raúl O. Cadena-Pereda

    2012-08-01

    Full Text Available Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0–100%. The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

  8. Water-soluble Hantzsch ester as switch-on fluorescent probe for efficiently detecting nitric oxide

    Science.gov (United States)

    Wang, Hui-Li; Liu, Fu-Tao; Ding, Ai-Xiang; Ma, Su-Fang; He, Lan; Lin, Lan; Lu, Zhong-Lin

    2016-12-01

    A water soluble Hantzsch ester derivative of coumarin, DHPS, was synthesized and successfully applied in the fluorescent sensing nitric oxide (NO) in aqueous solution. The fluorescence of probe DHPS is extremely weak, while its fluorescence was greatly switched on upon the addition of NO solution and showed high selectivity and sensitivity to NO. The limitation of the detection was calculated to be 18 nM. The NO-induced aromatization of dihydropyridine in DHPS to pyridine derivative (PYS) proved to be the switching mechanism for the fluorescent sensing process, which was confirmed through spectra characterization and computation study. Cytotoxicity assay demonstrated both DHPS and PYS are biocompatible, the DHPS was successfully applied to track the endogenously produced NO in the RAW 264.7 cells.

  9. Water-soluble polythiophene-single walled carbon Nanotube bulk heterojunction.

    Science.gov (United States)

    Kim, Daeyoung; Choi, Jaewu

    2011-10-01

    Two symmetrical terminal electrodes made of indium tin oxide (ITO) were employed to study the current-voltage characteristics of a bulk-heterojunction consisting of water soluble polythiophene and single walled carbon nanotubes (SWCNT). However, the current-voltage curves were asymmetrical, attributed to the polarization induced by the initial bias voltage. The polymer-SWCNT heterojunction were superior to the pristine polymer in both dark conductivity and photoconductivity by two orders of magnitude. Additionally, the open-cell voltage of 0.075 V was observed from the heterojunction even though the electrodes were symmetrical. The high conductivity and photoresponse originated from the high conductivity, high interconnectivity and hole doping capability of CNT.

  10. 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)

  11. [Water-soluble galactomannan from the seeds of Lotus corniculatus L.: structure and properties].

    Science.gov (United States)

    Egorov, A V; Mestechkina, N M; Plennik, R Ia; Shcherbukhin, V D

    2003-01-01

    Galactomannan, a water-soluble heteropolysaccharide, was isolated from the seed of Far-Eastern population of ground honeysuckle Lotus corniculatus L. (yield, 1.65%). Analysis of this galactomannan showed that is consists of D-mannose and D-galactose residues (molar ratio, 1.22:1). Its aqueous solutions were characterized by specific rotation [alpha]D = +84.10 and characteristic viscosity [eta] = 559 ml/g. Analysis of this heteropolysaccharide using chemical and enzymatic procedures, as well as IR- and 13C-NMR spectroscopy, showed that its main chain comprises 1,4-beta-D-mannopyranose residues, 95.5% of which are substituted at C-6 with single residues of alpha-D-galactopyranose.

  12. A Highly Efifcient and Selective Water-Soluble Bimetallic Catalyst for Hydrogenation of Chloronitrobenzene to Chloroaniline

    Institute of Scientific and Technical Information of China (English)

    Zhou Yafen; Yang Wenjuan; Zhou Limei; Wang Manman; Ma Xiaoyan

    2015-01-01

    Selective hydrogenation of chloronitrobenzene (CNB) to chloroaniline (CAN) catalyzed by water-soluble Ru/Pt bimetallic catalyst in an aqueous-organic biphasic system was studied. It was found that the catalytic activity increased ob-viously due to the addition of platinum. Ru/Pt bimetallic catalysts exhibited a strong synergistic effect when the molar ratio of Pt was in the range of 5%—80%. Under the mild conditions including a temperature of 25℃, a hydrogen pressure of 1.0 MPa and a Pt molar ratio of 20%, the conversion of p-chloronitrobenzene (p-CNB) reached 99.9%, with the selectivity to p-chloroaniline (p-CAN) equating to 99.4%. The Ru/Pt catalyst also showed high activity and selectivity for the hydrogena-tion of other chloro-and dichloro-nitrobenzenes with different substituted positions. In addition, the catalyst can be recycled ifve times without signiifcant loss of activity.

  13. [Modulation of plant resistance to diseases by water-soluble chitosan].

    Science.gov (United States)

    Vasiukova, N I; Zinov'eva, S V; Il'inskaia, L I; Perekhod, E A; Chalenko, G I; Gerasimova, N G; Il'ina, A V; Varlamov, V P; Ozeretskovskaia, O L

    2001-01-01

    Low-molecular-weight water-soluble chitosan with a molecular weight of 5 kDa obtained after enzymatic hydrolysis of native crab chitosan was shown to display an elicitor activity by inducing the local and systemic resistance of Solanumi tuberosum potato and Lycopesicon esculentum tomato to Phytophthora infestans and nematodes, respectively. Chitosan induced the accumulation of phytoalexins in tissues of host plants, decreased the total content and changed the composition of free sterols producing adverse effects on infesters, activated chitinases, beta-glucanases, and lipoxygenases, and stimulated the generation of reactive oxygen species. The activation of protective mechanisms in plant tissues inhibited the growth of taxonomically different pathogens (parasitic fungus Phytophthora infestans and root knot nematode Meloidogyne incognita).

  14. Deep ultraviolet photoluminescence of water-soluble self-passivated graphene quantum dots.

    Science.gov (United States)

    Tang, Libin; Ji, Rongbin; Cao, Xiangke; Lin, Jingyu; Jiang, Hongxing; Li, Xueming; Teng, Kar Seng; Luk, Chi Man; Zeng, Songjun; Hao, Jianhua; Lau, Shu Ping

    2012-06-26

    Glucose-derived water-soluble crystalline graphene quantum dots (GQDs) with an average diameter as small as 1.65 nm (∼5 layers) were prepared by a facile microwave-assisted hydrothermal method. The GQDs exhibits deep ultraviolet (DUV) emission of 4.1 eV, which is the shortest emission wavelength among all the solution-based QDs. The GQDs exhibit typical excitation wavelength-dependent properties as expected in carbon-based quantum dots. However, the emission wavelength is independent of the size of the GQDs. The unique optical properties of the GQDs are attributed to the self-passivated layer on the surface of the GQDs as revealed by electron energy loss spectroscopy. The photoluminescence quantum yields of the GQDs were determined to be 7-11%. The GQDs are capable of converting blue light into white light when the GQDs are coated onto a blue light emitting diode.

  15. Interaction of Globular Plasma Proteins with Water-Soluble CdSe Quantum Dots.

    Science.gov (United States)

    Pathak, Jyotsana; Rawat, Kamla; Sanwlani, Shilpa; Bohidar, H B

    2015-06-08

    The interactions between water-soluble semiconductor quantum dots [hydrophilic 3-mercaptopropionic acid (MPA)-coated CdSe] and three globular plasma proteins, namely, bovine serum albumin (BSA), β-lactoglobulin (β-Lg) and human serum albumin (HSA), are investigated. Acidic residues of protein molecules form electrostatic interactions with these quantum dots (QDs). To determine the stoichiometry of proteins bound to QDs, we used dynamic light scattering (DLS) and zeta potential techniques. Fluorescence resonance energy transfer (FRET) experiments revealed energy transfer from tryptophan residues in the proteins to the QD particles. Quenching of the intrinsic fluorescence of protein molecules was noticed during this binding process (hierarchy HSA<β-Lg

  16. Modeling the formation of soluble microbial products (SMP in drinking water biofiltration

    Directory of Open Access Journals (Sweden)

    Xin YU

    2008-09-01

    Full Text Available Both a theoretical and an empirical model were developed for predicting the formation of soluble microbial products (SMP during drinking water biofiltration. Four pilot-scale biofilters with ceramsite as the medium were fed with different acetate loadings for the determination of SMP formation. Using numerically simulated and measured parameters, the theoretical model was developed according to the substrate and biomass balance. The results of this model matched the measured data better for higher SMP formation but did not fit well when SMP formation was lower. In order to better simulate the reality and overcome the difficulties of measuring the kinetic parameters, a simpler empirical model was also developed. In this model, SMP formation was expressed as a function of fed organic loadings and the depth of the medium, and a much better fit was obtained.

  17. Reversible Covalent and Supramolecular Functionalization of Water-Soluble Gold(I) Complexes.

    Science.gov (United States)

    Kemper, Benedict; von Gröning, Maximilian; Lewe, Vanessa; Spitzer, Daniel; Otremba, Tobias; Stergiou, Natascha; Schollmeyer, Dieter; Schmitt, Edgar; Ravoo, Bart Jan; Besenius, Pol

    2017-02-09

    The ligation of gold(I) metalloamphiphiles with biomolecules is reported, using water-soluble Au(I) -N-alkynyl substituted maleimide complexes. For this purpose, two different polar ligands were applied: 1) a neutral, dendritic tetraethylene glycol-functionalized phosphane and 2) a charged, sulfonated N-heterocyclic carbene (NHC). The retro Diels-Alder reaction of a furan-protected maleimide gold(I) complex, followed by cycloaddition with a diene-functionalized biotin under mild conditions leads to a novel gold(I) metalloamphiphile. The strong streptavidin-biotin binding affinity in buffered aqueous solution of the resulting biotin alkynyl gold(I) phosphane conjugate remains intact. The cytotoxicity of the biotinylated gold(I) complex against a T47D human breast cancer cell line is higher than for cisplatin.

  18. Photocatalytic Degradation of Water-Soluble Dyes by LaCoO3

    Institute of Scientific and Technical Information of China (English)

    傅希贤; 杨秋华; 王俊珍; 白树林; 桑丽霞

    2003-01-01

    Perovskite-type oxides LaCoO3 was prepared by citrate method in granula of 20~30 nm. Using a fluorescent Hg lamp or sunlight as irradiator, the degradation experiments of various water-soluble dyes were carried out in the suspension system of LaCoO3. The results show that the perovskite-type oxide LaCoO3 has good photocatalytic activity. With the study of X-ray photoelectron spectroscopy and photoacoustic spectra, its photocatalytic activity is mainly related with the factors such as the d-electron structure of ion Co3+, Co-O binding energy and adsorbed oxygen on the surface etc.

  19. Super fast detection of latent fingerprints with water soluble CdTe quantum dots.

    Science.gov (United States)

    Cai, Kaiyang; Yang, Ruiqin; Wang, Yanji; Yu, Xuejiao; Liu, Jianjun

    2013-03-10

    A new method based on the use of highly fluorescent water-soluble cadmium telluride (CdTe) quantum dots (QDs) capped with mercaptosuccinic acid (MSA) was explored to develop latent fingerprints. After optimized the effectiveness of QDs method contains pH value and developing time, super fast detection was achieved. Excellent fingerprint images were obtained in 1-3s after immersed the latent fingerprints into quantum dots solution on various non-porous surfaces, i.e. adhesive tape, transparent tape, aluminum foil and stainless steel. High sensitivity of the new latent fingerprints develop method was obtained by developing the fingerprints pressed on aluminum foil successively with the same finger. Compared with methyl violet and rhodamine 6G, the MSA-CdTe QDs showed the higher develop speed and fingerprint image quality. Clear image can be maintained for months by extending exposure time of CCD camera, storing fingerprints in a low temperature condition and secondary development.

  20. The Quality of Dory Fillets based on Water Soluble Protein, Color, and Myoglobin Concentration

    Directory of Open Access Journals (Sweden)

    Nurfajrin Nisa

    2016-04-01

    Full Text Available Fillet of dory is very easy to be find in Indonesian market with various brand and produsen.Imported dory fillet is preferred by consumer so far because it has a white color compare than localfillets. Color is the important parameter that used by consumers to determine the quality of filet. Thisstudy was aimed to determine the quality of local and imported fillets, including protein profile usingSDS PAGE, color measurement, and myoglobin extractability. The results of water soluble protein profilesshowed dory fillet contained 13-15 bands. The redness value (a* of local fillet (DN, DL, DM was highercompared others. However, imported fillet (DI had the highest if redness index (a/b. Imported fillet (DIshowed the lowest concentration of myoglobin compared other samples.

  1. The Quality of Dory Fillets based on Water Soluble Protein, Color, and Myoglobin Concentration

    Directory of Open Access Journals (Sweden)

    Nurfajrin Nisa

    2016-04-01

    Full Text Available Fillet of dory is very easy to be find in Indonesian market with various brand and produsen. Imported dory fillet is preferred by consumer so far because it has a white color compare than local fillets. Color is the important parameter that used by consumers to determine the quality of filet. This study was aimed to determine the quality of local and imported fillets, including protein profile using SDS PAGE, color measurement, and myoglobin extractability. The results of water soluble protein profiles showed dory fillet contained 13-15 bands. The redness value (a* of local fillet (DN, DL, DM was higher compared others. However, imported fillet (DI had the highest if redness index (a/b. Imported fillet (DI showed the lowest concentration of myoglobin compared other samples.

  2. 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

    . However, this strategy only led to a small number of marketed products usually because of inadequate physical stability of the drug (crystallization). In this study, we investigated a fundamentally different approach to stabilize the amorphous form of drugs, namely the use of amino acids as small...... 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...... and the amino acids arginine, phenylalanine, tryptophan and tyrosine were prepared by vibrational ball milling. Solid-state characterization with X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) revealed that the various blends could be prepared as homogeneous, single phase co...

  3. 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.

  4. Novel water-soluble prodrugs of acyclovir cleavable by the dipeptidyl-peptidase IV (DPP IV/CD26) enzyme.

    Science.gov (United States)

    Diez-Torrubia, Alberto; Cabrera, Silvia; de Castro, Sonia; García-Aparicio, Carlos; Mulder, Gwenn; De Meester, Ingrid; Camarasa, María-José; Balzarini, Jan; Velázquez, Sonsoles

    2013-01-01

    We herein report for the first time the successful use of the dipeptidyl peptidase IV (DPPIV/CD26) prodrug approach to guanine derivatives such as the antiviral acyclovir (ACV). The solution- and solid-phase synthesis of the tetrapeptide amide prodrug 3 and the tripeptide ester conjugate 4 of acyclovir are reported. The synthesis of the demanding tetrapeptide amide prodrug of ACV 3 was first established in solution and successfully transferred onto solid support by using Ellman's dihydropyran (DHP) resin. In contrast with the valyl ester prodrug (valacyclovir, VACV), the tetrapeptide amide prodrug 3 and the tripeptide ester conjugate 4 of ACV proved fully stable in PBS. Both prodrugs converted to VACV (for 4) or ACV (for 3) upon exposure to purified DPPIV/CD26 or human or bovine serum. Vildagliptin, a potent inhibitor of DPPIV/CD26 efficiently inhibited the DPPIV/CD26-catalysed hydrolysis reaction. Both amide and ester prodrugs of ACV showed pronounced anti-herpetic activity in cell culture and significantly improved the water solubility in comparison with the parent drug.

  5. Bilirubin adsorption properties of water-soluble adsorbents with different cyclodextrin cavities in plasma dialysis system.

    Science.gov (United States)

    Wang, Zhi; Cao, Yaming; Wei, Houliang; Jia, Lingyun; Xu, Li; Xie, Jian

    2012-02-01

    In this study, we explored the use of α-, β- or γ-cyclodextrin (CD)-grafted polyethyleneimine (PEI) as water-soluble adsorbent for removing excess plasma bilirubin. To evaluate the bilirubin-binding capacity of these adsorbents, bovine serum albumin (BSA) solution or plasma with high level of bilirubin were dialyzed against CD-PEI-spiked dialysate. In BSA solution with an initial biliurbin concentration of 171.5mg/L, α-CD-PEI, β-CD-PEI and γ-CD-PEI achieved adsorption capacities of 2.5, 5.8 and 3.8 mg/g, respectively. In a plasma dialysis system, 45.6% of bilirubin (260 mg/L) was removed from 200 mL plasma by 1L dialysate spiked with 10mg/mL β-CD-PEI, which was significantly higher than that removed by the same volume of BSA-spiked dialysate (Padsorption was related to the CD functional group, not the PEI matrix. Subsequent molecular docking study indicated that the size of CD cavity could affect the affinity energy of CD-bilirubin complex. The cavity of β-CD was most suitable for accommodating the pyrrole rings of bilirubin. The inclusion complex of bilirubin and β-CD in the molar ratio of 1:2 was more logical in terms of affinity energy. All the results demonstrated the potential of β-CD-PEI (water-soluble adsorbent) as an effective agent for removing of bilirubin from plasma in dialysis system. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Magnetically assisted fluorescence ratiometric assays for adenosine deaminase using water-soluble conjusated polymers

    Institute of Scientific and Technical Information of China (English)

    HE Fang; YU MingHui; WANG Shu

    2009-01-01

    A magnetically assisted fluorescence ratiometric technique has been developed for adenosine deami-nase assays with high sensitivity using water-soluble cationic conjugated polymers (CCPs).The assay contains three elements:a biotin-labeled aptamer of adenosine (biotin-aptamer),a signaling probe single-stranded DNA-tagged fiuorescein at terminus (ssDNA-FI) and a CCP.The specific binding of adenosine to biotin-aptamer makes biotin-aptamer and ssDNA-FI unhybridized,and the ssDNA-FI is washed out after streptavidin-coated magnetic beads are added and separated from the assay solution under magnetic field.In this case,after the addition of CCP to the magnetic beads solution,the fluo-rescence resonance energy transfer (FRET) from CCP to fluorescein is inefficient.Upon adding adenosine deaminase,the adenosine is converted into inosine,and the biotin-aptamer is hybridized with ssDNA-FI to form doubled stranded DNA (biotin-dsDNA-FI).The ssONA-FI is attached to the mag-netic beads at the separation step,and the addition of CCP to the magnetic beads solution leads to efficient FRET from CCP to fluorescein.Thus the adenosine deaminase activity can be monitored by fluorescence spectra in view of the intensity decrease of CCP emission or the increase of fluorescein emission in aqueous solutions.The assay integrates surface-functionalized magnetic particles with significant amplification of detection signal of water-soluble cationic conjugated polymers.

  7. Water soluble organic aerosols in indo gangetic plain (IGP): Insights from aerosol mass spectrometry.

    Science.gov (United States)

    Chakraborty, Abhishek; Rajeev, Pradhi; Rajput, Prashant; Gupta, Tarun

    2017-12-01

    Filter samples collected during winter of 2015-16 from two polluted urban locations (Allahabad and Kanpur) residing within Indo-Gangetic plain (IGP) showed high levels of water-soluble organic aerosols (WSOA). Total organic aerosols (OA) in submicron fraction, measured at Kanpur in real time via Aerosol Mass Spectrometer also showed substantially high concentration levels. WSOA to OA contribution in Kanpur was found to be very high (around 55%) indicating significant contributions from secondary OA (SOA). On average, WSOA oxidation ratio (O/C) was found to be higher (15-20%) in Kanpur than at Allahabad. WSOA from Allahabad was found to be following a much shallower slope (-0.38) in Van Krevelen diagram (H/C vs O/C plot) than Kanpur (-0.58). These differences suggest different composition and chemistry of WSOA at these two different locations. O/C ratios of WSOA were found to be much higher (~40%) than that of OA and independent of WSOA loading. Higher OA loadings were found to be associated with less oxidized primary OAs (POA) and culminated into lower WSOA/OA ratios. The presence of organo sulfate in filter samples from both locations indicate a significant amount of aqueous processing of organics. Concentrations and characteristics of water insoluble OA (WIOA) in Kanpur revealed that although they are present in significant quantity, their oxidation levels are much (almost 3 times) lower than that of WSOA. This finding indicates that less oxidized OAs are less soluble in line with the conventional wisdom. This study provides the first insight into oxidation levels and evolution of WSOA from India and also explores the interplay between WSOA and OA characteristics based on AMS measurements. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Streptavidin sensor and its sensing mechanism based on water-soluble fluorescence conjugated polymer

    Science.gov (United States)

    Chen, Yanguo; Hong, Peng; Xu, Baoming; He, Zhike; Zhou, Baohan

    2014-03-01

    Fluorescence quenching effect of water-soluble anionic conjugated polymer (CP) (poly[5-methoxy-2-(3-sulfopoxy)-1,4-phenylenevinylene] (MPS-PPV)) by [Re(N-N)(CO)3(py-CH2-NH-biotin)](PF6) [N-N=2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline; py-CH2-NH-biotin=N-[(4-pyridyl) methyl] biotinamide] (Re-Biotin) and fluorescence recovery in the presence of streptavidin (or avidin) were investigated using Re-Biotin as quencher tether ligand (QTL) probe. Meanwhile, the mechanisms of fluorescence quenching and recovery were discussed to provide new thoughts to design biosensor based on water-soluble CPs. The results indicate that the sensing mechanisms of streptavidin sensor or avidin sensor, using Re-Biotin as QTL probe, are the same and stable, whether in non-buffer system (aqueous solution) or different buffer systems [0.01 mol·L-1 phosphate buffered solution (pH = 7.4), 0.1 mol·L-1 ammonium carbonate buffered solution (pH = 8.9)]. There exists specific interactions between streptavidin (or avidin) and biotin of Re-Biotin. Fluorescence quenching and recovery processes of MPS-PPV are reversible. Mechanisms of Re-Biotin quenching MPS-PPV fluorescence can be interpreted as strong electrostatic interactions and charge transferences between Re-Biotin and MPS-PPV. Fluorescence recovery mechanisms of Re-Biotin-MPS-PPV system can be interpreted as specific interactions between streptavidin (or avidin) and biotin of Re-Biotin making Re-Biotin far away from MPS-PPV. Avidin or strptavidin as re-Biotin probe can not only be quantitatively determinated, but also be identified.

  9. Design and synthesis of monofunctionalized, water-soluble conjugated polymers for biosensing and imaging applications.

    Science.gov (United States)

    Traina, Christopher A; Bakus, Ronald C; Bazan, Guillermo C

    2011-08-17

    Water-soluble conjugated polymers with controlled molecular weight characteristics, absence of ionic groups, high emission quantum yields, and end groups capable of selective reactions of wide scope are desirable for improving their performance in various applications and, in particular, fluorescent biosensor schemes. The synthesis of such a structure is described herein. 2-Bromo-7-iodofluorene with octakis(ethylene glycol) monomethyl ether chains at the 9,9'-positions, i.e., compound 4, was prepared as the reactive premonomer. A high-yielding synthesis of the organometallic initiator (dppe)Ni(Ph)Br (dppe = 1,2-bis(diphenylphosphino)ethane) was designed and implemented, and the resulting product was characterized by single-crystal X-ray diffraction techniques. Polymerization of 4 by (dppe)Ni(Ph)Br can be carried out in less than 30 s, affording excellent control over the average molecular weight and polydispersity of the product. Quenching of the polymerization with [2-(trimethylsilyl)ethynyl]magnesium bromide yields silylacetylene-terminated water-soluble poly(fluorene) with a photoluminescence quantum efficiency of 80%. Desilylation, followed by copper-catalyzed azide-alkyne cycloaddition reaction, yields a straightforward route to introduce a wide range of specific end group functionalities. Biotin was used as an example. The resulting biotinylated conjugated polymer binds to streptavidin and acts as a light-harvesting chromophore to optically amplify the emission of Alexa Fluor-488 chromophores bound onto the streptavidin. Furthermore, the biotin end group makes it possible to bind the polymer onto streptavidin-functionalized cross-linked agarose beads and thereby incorporate a large number of optically active segments.

  10. 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.

  11. Water soluble drug releasing soft contact lens in response to pH of tears

    Science.gov (United States)

    Kim, G.; Noh, H.

    2016-06-01

    Human tear characteristics including pH and compositions can vary significantly depending on physical and environmental factors. Contact lenses directly contact with human tears can be swelled or de-swelled depending on the pH of the solution due to the nature of the hydrogel. For examples, anionic hydrogels, when the solution's pH is low, is shrunken due to the electric attraction force within the hydrogel network; the opposite phenomenon appears when the solution is basic. The purpose of this study was to evaluate the extent of water soluble drug, hydroxyl propyl methyl cellulose, released from contact lens according to the pH of the artificial tears. Artificial tears are prepared by mixing lysozyme, albumin, sodium chloride, potassium chloride, and calcium chloride following physiological concentrations. Hydrogel contact lens was thermally polymerized using HEMA, EGDMA, and AIBN. The prepared hydrogel lens was immersed in drug for 3 hours and the eluted drug mass was measured as a function of the time. As a result, the drug was released from the lens for 12 hours in all the pH of artificial tears. At the lower pH of artificial tears (pH 5.8), the total amount of dye emitted from the lens was increased than the total amount of dye emitted at the basic tear (pH 8.4). Also, initial burst at acidic tears was increased within 1 hour. Release pattern of water-soluble drug from hydrogel lens turned out to be different depending on the pH of the artificial tears. When designing drug releasing contact lens, physiological pH of tears should be considered.

  12. Impact of tree cutting on water-soluble organic compounds in podzolic soils of the European North-East

    Science.gov (United States)

    Lapteva, Elena; Bondarenko, Natalia; Shamrikova, Elena; Kubik, Olesya; Punegov, Vasili

    2016-04-01

    Water-soluble organic compounds (WOCs) and their single components, i.e. low-molecular organic acids, alcohols, and carbohydrates, attain a great deal of attention among soil scientists. WOCs are an important component of soil organic matter (SOM) and form as a results of different biological and chemical processes in soils. These processes are mainly responsible for formation and development of soils in aboveground ecosystems. The purpose of the work was identifying qualitative and quantitative composition of low-molecular organic substances which form in podzolic loamy soils against natural reforestation after spruce forest cutting. The studies were conducted on the territory of the European North-East of Russia, in the middle taiga subzone (Komi Republic, Ust-Kulom region). The study materials were soil of undisturbed bilberry spruce forest (Sample Plot 1 (SP1)) and soils of different-aged tree stands where cutting activities took place in winter 2001/2002 (SP2) and 1969/1970 (SP3). Description of soils and vegetation cover on the plots is given in [1]. Low-molecular organic compounds in soil water extracts were identified by the method of gas chromatography mass-spectrometry [2, 3]. Finally, reforestationafterspruceforestcutting was found to be accompanied by different changes in soil chemical composition. In contrast with soils under undisturbed spruce forest, organic soil horizons under different-aged cuts decreased in organic carbon reserves and production of low-molecular organic compounds, changed in soil acidity. Within the soil series of SP1→SP2→SP3, the highest content of WOCs was identified for undisturbed spruce forest (738 mg kg-1 soil). In soils of coniferous-deciduous forests on SP1 and SP3, WOC content was 294 and 441 mg kg-1 soil, correspondingly. Soils at cuts decreased in concentration of any water-soluble low-molecular SOM components as low-molecular acids, alcohols, and carbohydrates. Structure of low-molecular WOCs in the study podzolic

  13. Carbamazepine solubility enhancement in tandem with swellable polymer osmotic pump tablet: A promising approach for extended delivery of poorly water-soluble drugs

    Directory of Open Access Journals (Sweden)

    Hadjira Rabti

    2014-06-01

    Full Text Available Elementary osmotic pump (EOP is a unique extended release (ER drug delivery system based on the principle of osmosis. It has the ability to minimize the amount of the drug, accumulation and fluctuation in drug level during chronic uses. Carbamazepine (CBZ, a poorly water-soluble antiepileptic drug, has serious side effects on overdoses and chronic uses. The aim of the present study was to design a new EOP tablet of CBZ containing a solubility enhancers and swellable polymer to reduce its side effects and enhance the patient compliance. Firstly, a combination of solubilizing carriers was selected to improve the dissolution of the slightly soluble drug. Then, designing the new EOP tablet and investigating the effect of different variables of core and coat formulations on drug release behavior by single parameter optimization and by Taguchi orthogonal design with analysis of variance (ANOVA, respectively. The results showed that CBZ solubility was successfully enhanced by a minimum amount of combined polyvinyl pyrrolidone (PVP K30 and sodium lauryl sulfate (SLS. The plasticizer amount and molecular weight (MW together with the osmotic agent amount directly affect the release rate whereas the swellable polymer amount and viscosity together with the semi-permeable membrane (SPM thickness inversely influence the release rate. In addition, the tendency of following zero order kinetics was mainly affected by the coat components rather than those of the core. Further, orifice size does not have any significant effect on the release behavior within the range of 0.1 mm to 0.8 mm. In this study we report the successful formulation of CBZ-EOP tablets, which were similar to the marketed product Tegretol CR 200 and able to satisfy the USP criterion limits and to deliver about 80% of CBZ at a rate of approximately zero order for up to 12 h.

  14. Effects of Water-Soluble Co-Solvent on Properties of W/O Pickering Emulsions

    Institute of Scientific and Technical Information of China (English)

    张旭斌; 谢世巍; 蔡旺锋; 王富民

    2016-01-01

    Effects of water-soluble co-solvents(WSCs)on the properties of water/oil Pickering emulsions were investigated. Pickering emulsions were prepared in the system of 1,2,4-trimethylbenzene(TMB)/ hydrophobic sil-ica/water with varied concentrations of WSCs(ethanol, acetic acid and glycerin). Mean droplet diameter distribu-tions of the obtained emulsions were studied to investigate the effects of WSCs types and concentrations. The re-sults demonstrated that mean droplet diameter distributions decreased at first and then increased with the increase of WSC concentration. Moreover, the effect of WSC concentration on the phase inversion locus was further investi-gated. At the same time, infrared radiation(IR)spectrometer was used to investigate the mechanism. The results showed that the WSC attaching on hydrophobic silica changed the wettability of the particles, which facilitated the formation and phase inversion of the emulsion. The hydrogen bonds between the co-solvent groups attaching on the solid particles made a great effect on the droplet size of the emulsion and strengthened the interaction among emul-sifiers. Overall, proper WSC was in favor of the stability of Pickering emulsion.

  15. Nanocomposite hydrogels based on water soluble polymer and montmorillonite-Na+

    Directory of Open Access Journals (Sweden)

    Fatiha Reguieg

    2015-09-01

    Full Text Available A series of composites hydrogels based on Poly (1,3-dioxolane (PDXL,water soluble polymer, were synthesized directly in water by free-radical homopolymerization of a,w-methacryloyloxy PDXL macromonomers using hydrophilic sodium Montmorillonite clay: Maghnite-Na+ (Mag-Na+ and potassium persulfate as an initiator. These materials were characterized by X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR, thermogravimetric analysis (ATG and their equilibrium swelling behavior in water and were compared with those of pure hydrogels prepared without Mag-Na+. X-ray diffraction and Infrared spectroscopy confirmed insertion of clay into polymer. The thermal decomposition temperature of the hydrogels based on maghnite-Na+ was found to be higher than of pure hydrogels. At the same time, the influence of the macromonomer precursor molar mass value, its concentration and the quantities of Mag-Na+, on the values of the volume degree of equilibrium swelling were studied. The results showed that the volume degree of equilibrium swelling was investigated as a function of the clay content. However, whether the concentration of macromonomer precursor increased, the volume or weight degree of equilibrium swelling of hydrogels all decreased. The addition of Mag-Na+ particles changed the crosslinking density of hydrogels.

  16. Quantitative oral dosing of water soluble and lipophilic contaminants in the Japanese medaka (Oryzias latipes)

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Irv; Reed, Stacey M.; Pratt, Amanda V.; Skillman, Ann D.

    2007-02-01

    Quantitative oral dosing in fish can be challenging, particularly with water soluble contaminants, which can leach into the aquarium water prior to ingestion. We applied a method of bioencapsulation using newly hatched brine shrimp (Artemia franciscana) nauplii to study the toxicokinetics of five chlorinated and brominated halogenated acetic acids (HAAs), which are drinking water disinfection by-products. These results are compared to those obtained in a previous study using a polybrominated diphenyl ether (PBDE-47), a highly lipophilic chemical. The HAAs and PBDE-47 were bioencapsulated using freshly hatched A. franciscana nauplii after incubation in concentrated solutions of the study chemicals for 18 h. Aliquots of the brine shrimp were quantitatively removed for chemical analysis and fed to individual fish that were able to consume 400–500 nauplii in less than 5min. At select times after feeding, fish were euthanized and the HAA or PBDE-47 content determined. The absorption of HAAs was quantitatively similar to previous studies in rodents: rapid absorptionwith peak body levels occurringwithin 1–2 h, then rapidly declining with elimination half-life of 0.3–3 h depending on HAA. PBDE-47 was more slowly absorbed with peak levels occurring by 18 h and very slowly eliminated with an elimination half-life of 281 h.

  17. QSPR study of the water solubility of a diverse set of agrochemicals ...

    African Journals Online (AJOL)

    model was further illustrated using various evaluation techniques: leave- one- out cross- validation, bootstrap, randomization ... therefore the solubility of a new compound ..... adhesive interactions determine the amount of ... bonding. In order to predict solubility accurately, all these factors correlated with solubility should.

  18. A water-soluble polycarbonate with dimethylamino pendant groups prepared by enzyme-catalyzed ring-opening polymerization.

    Science.gov (United States)

    Zhang, Xiaojin; Cai, Mengmeng; Zhong, Zhenlin; Zhuo, Renxi

    2012-04-23

    A water-soluble polycarbonate with dimethylamino pendant groups, poly(2-dimethylaminotrimethylene carbonate) (PDMATC), is synthesized and characterized. First, the six-membered carbonate monomer, 2-dimethylaminotrimethylene carbonate (DMATC), is prepared via the cyclization reaction of 2-(dimethylamino)propane-1,3-diol with triphosgene in the presence of triethylamine. Although the attempted ring-opening polymerization (ROP) of DMATC with Sn(Oct)(2) as a catalyst fails, the ROP of DMATC is successfully carried out with Novozym-435 as a catalyst to give water-soluble aliphatic polycarbonate PDMATC with low cytotoxicity and good degradability.

  19. Preparation of water-soluble multi-walled carbon nanotubes by Ce(Ⅳ)-induced redox radical polymerization

    Institute of Scientific and Technical Information of China (English)

    Dong Yang; Xiaohong Zhang; Changchun Wang; Yuechao Tang; Junjun Li; Jianhua Hu

    2009-01-01

    Poly(acrylic acid), poly(N-isopropylacrylamide) and polyacrylamide functionalized MWNTs were prepared by Ce(IV)-induced redox radical polymerization. The reaction can be conducted in aqueous media at room temperature, and the polymer graft ratio increased with the increase of monomer feed ratio. MWNTs anchored with PAA on the surface are pH sensitive and exhibit a reversible assembly-deas-sembly response in aqueous solution, whereas those coated with PNIPAM are thermally sensitive. All the polymer-functionalized MWNTs are highly soluble in water to give robust stable black solutions. Such water-soluble MWNTs are promising for biological and biomedical applications.

  20. Aqueous-phase exfoliation of graphite in the presence of polyvinylpyrrolidone for the production of water-soluble graphenes

    Science.gov (United States)

    Bourlinos, Athanasios B.; Georgakilas, Vasilios; Zboril, Radek; Steriotis, Theodore A.; Stubos, Athanasios K.; Trapalis, Christos

    2009-12-01

    Treatment of crystalline graphite fine powder with an aqueous solution of the harmless and versatile substance polyvinylpyrrolidone under sonication results in water-soluble, polymer-protected graphene single layers without oxidation or destruction of the sp 2 character of the carbon core. The liquid-phase extraction of graphene monolayers was evidenced by TEM and AFM techniques, while their graphitic character was checked with Raman spectroscopy. Besides PVP, the water-soluble biopolymers albumin and sodic carboxymethylcellulose were also employed successfully in the aqueous-phase exfoliation of graphite, thereby supporting the generic character of the present method using a variety of suitable polymeric extractants.

  1. Protein extraction and 2-DE of water- and lipid-soluble proteins from bovine pericardium, a low-cellularity tissue.

    Science.gov (United States)

    Griffiths, Leigh G; Choe, Leila; Lee, Kelvin H; Reardon, Kenneth F; Orton, E Christopher

    2008-11-01

    Bovine pericardium (BP) is an important biomaterial used in the production of glutaraldehyde-fixed heart valves and tissue-engineering applications. The ability to perform proteomic analysis on BP is useful for a range of studies, including investigation of immune rejection after implantation. However, proteomic analysis of fibrous tissues such as BP is challenging due to their relative low-cellularity and abundance of extracellular matrix. A variety of methods for tissue treatment, protein extraction, and fractionation were investigated with the aim of producing high-quality 2-DE gels for both water- and lipid-soluble BP proteins. Extraction of water-soluble proteins with 3-(benzyldimethylammonio)-propanesulfonate followed by n-dodecyl beta-D-maltoside extraction and ethanol precipitation for lipid-soluble proteins provided the best combination of yield, spot number, and resolution on 2-DE gels (Protocol E2). ESI-quadrupole/ion trap or MALDI-TOF/TOF MS protein identifications were performed to confirm bovine origin and appropriate subcellular prefractionation of resolved proteins. Twenty-five unique, predominantly cytoplasmic bovine proteins were identified from the water-soluble fraction. Thirty-two unique, predominantly membrane bovine proteins were identified from the lipid-soluble fraction. These results demonstrated that the final protocol produced high-quality proteomic data from this important tissue for both cytoplasmic and membrane proteins.

  2. Synthesis of a highly water-soluble acacetin prodrug for treating experimental atrial fibrillation in beagle dogs.

    Science.gov (United States)

    Liu, Hui; Wang, Ya-Jing; Yang, Lei; Zhou, Mei; Jin, Man-Wen; Xiao, Guo-Sheng; Wang, Yan; Sun, Hai-Ying; Li, Gui-Rong

    2016-05-10

    We previously reported that duodenal administration of the natural flavone acacetin can effectively prevent the induction of experimental atrial fibrillation (AF) in canines; however, it may not be used intravenously to terminate AF due to its poor water-solubility. The present study was to design a water-soluble prodrug of acacetin and investigate its anti-AF effect in beagle dogs. Acacetin prodrug was synthesized by a three-step procedure. Aqueous solubility, bioconversion and anti-AF efficacy of acacetin prodrug were determined with different methodologies. Our results demonstrated that the synthesized phosphate sodium salt of acacetin prodrug had a remarkable increase of aqueous solubility in H2O and clinically acceptable solution (5% glucose or 0.9% NaCl). The acacetin prodrug was effectively converted into acacetin in ex vivo rat plasma and liver microsome, and in vivo beagle dogs. Intravenous infusion of acacetin prodrug (3, 6 and 12 mg/kg) terminated experimental AF without increasing ECG QTc interval in beagle dogs. The intravenous LD50 of acacetin prodrug was 721 mg/kg in mice. Our preclinical study indicates that the synthesized acacetin prodrug is highly water-soluble and safe; it effectively terminates experimental AF in beagle dogs and therefore may be a promising drug candidate for clinical trial to treat patients with acute AF.

  3. Water-soluble LYNX1 residues important for interaction with muscle-type and/or neuronal nicotinic receptors.

    Science.gov (United States)

    Lyukmanova, Ekaterina N; Shulepko, Mikhail A; Buldakova, Svetlana L; Kasheverov, Igor E; Shenkarev, Zakhar O; Reshetnikov, Roman V; Filkin, Sergey Y; Kudryavtsev, Denis S; Ojomoko, Lucy O; Kryukova, Elena V; Dolgikh, Dmitry A; Kirpichnikov, Mikhail P; Bregestovski, Piotr D; Tsetlin, Victor I

    2013-05-31

    Human LYNX1, belonging to the Ly6/neurotoxin family of three-finger proteins, is membrane-tethered with a glycosylphosphatidylinositol anchor and modulates the activity of nicotinic acetylcholine receptors (nAChR). Recent preparation of LYNX1 as an individual protein in the form of water-soluble domain lacking glycosylphosphatidylinositol anchor (ws-LYNX1; Lyukmanova, E. N., Shenkarev, Z. O., Shulepko, M. A., Mineev, K. S., D'Hoedt, D., Kasheverov, I. E., Filkin, S. Y., Krivolapova, A. P., Janickova, H., Dolezal, V., Dolgikh, D. A., Arseniev, A. S., Bertrand, D., Tsetlin, V. I., and Kirpichnikov, M. P. (2011) NMR structure and action on nicotinic acetylcholine receptors of water-soluble domain of human LYNX1. J. Biol. Chem. 286, 10618-10627) revealed the attachment at the agonist-binding site in the acetylcholine-binding protein (AChBP) and muscle nAChR but outside it, in the neuronal nAChRs. Here, we obtained a series of ws-LYNX1 mutants (T35A, P36A, T37A, R38A, K40A, Y54A, Y57A, K59A) and examined by radioligand analysis or patch clamp technique their interaction with the AChBP, Torpedo californica nAChR and chimeric receptor composed of the α7 nAChR extracellular ligand-binding domain and the transmembrane domain of α1 glycine receptor (α7-GlyR). Against AChBP, there was either no change in activity (T35A, T37A), slight decrease (K40A, K59A), and even enhancement for the rest mutants (most pronounced for P36A and R38A). With both receptors, many mutants lost inhibitory activity, but the increased inhibition was observed for P36A at α7-GlyR. Thus, there are subtype-specific and common ws-LYNX1 residues recognizing distinct targets. Because ws-LYNX1 was inactive against glycine receptor, its "non-classical" binding sites on α7 nAChR should be within the extracellular domain. Micromolar affinities and fast washout rates measured for ws-LYNX1 and its mutants are in contrast to nanomolar affinities and irreversibility of binding for α-bungarotoxin and similar

  4. Water-soluble LYNX1 Residues Important for Interaction with Muscle-type and/or Neuronal Nicotinic Receptors*

    Science.gov (United States)

    Lyukmanova, Ekaterina N.; Shulepko, Mikhail A.; Buldakova, Svetlana L.; Kasheverov, Igor E.; Shenkarev, Zakhar O.; Reshetnikov, Roman V.; Filkin, Sergey Y.; Kudryavtsev, Denis S.; Ojomoko, Lucy O.; Kryukova, Elena V.; Dolgikh, Dmitry A.; Kirpichnikov, Mikhail P.; Bregestovski, Piotr D.; Tsetlin, Victor I.

    2013-01-01

    Human LYNX1, belonging to the Ly6/neurotoxin family of three-finger proteins, is membrane-tethered with a glycosylphosphatidylinositol anchor and modulates the activity of nicotinic acetylcholine receptors (nAChR). Recent preparation of LYNX1 as an individual protein in the form of water-soluble domain lacking glycosylphosphatidylinositol anchor (ws-LYNX1; Lyukmanova, E. N., Shenkarev, Z. O., Shulepko, M. A., Mineev, K. S., D'Hoedt, D., Kasheverov, I. E., Filkin, S. Y., Krivolapova, A. P., Janickova, H., Dolezal, V., Dolgikh, D. A., Arseniev, A. S., Bertrand, D., Tsetlin, V. I., and Kirpichnikov, M. P. (2011) NMR structure and action on nicotinic acetylcholine receptors of water-soluble domain of human LYNX1. J. Biol. Chem. 286, 10618–10627) revealed the attachment at the agonist-binding site in the acetylcholine-binding protein (AChBP) and muscle nAChR but outside it, in the neuronal nAChRs. Here, we obtained a series of ws-LYNX1 mutants (T35A, P36A, T37A, R38A, K40A, Y54A, Y57A, K59A) and examined by radioligand analysis or patch clamp technique their interaction with the AChBP, Torpedo californica nAChR and chimeric receptor composed of the α7 nAChR extracellular ligand-binding domain and the transmembrane domain of α1 glycine receptor (α7-GlyR). Against AChBP, there was either no change in activity (T35A, T37A), slight decrease (K40A, K59A), and even enhancement for the rest mutants (most pronounced for P36A and R38A). With both receptors, many mutants lost inhibitory activity, but the increased inhibition was observed for P36A at α7-GlyR. Thus, there are subtype-specific and common ws-LYNX1 residues recognizing distinct targets. Because ws-LYNX1 was inactive against glycine receptor, its “non-classical” binding sites on α7 nAChR should be within the extracellular domain. Micromolar affinities and fast washout rates measured for ws-LYNX1 and its mutants are in contrast to nanomolar affinities and irreversibility of binding for α-bungarotoxin and

  5. Toxicity of water-soluble gasoline fractions to fourth-instar larvae of the mosquito Aedes aegypti L

    Energy Technology Data Exchange (ETDEWEB)

    Berry, W.O.; Brammer, J.D.

    1977-07-01

    The toxicity of water-soluble components of gasoline to laboratory-reared fourth-instar larvae of the mosquito, Aedes aegypti (L.) was investigated. A median lethal dose (LD/sub 50/) and a non-lethal dose (NLD) were established for these larvae following a 24 h exposure to water-soluble fractions of benzene, toluene, and xylenes. Based on the actual amount of each component in solution, static toxicity/bioassays showed that acute toxicity of these monoaromatics increased in the sequence benzene, toluene, xylenes. However, toxicity increased in the sequence xylenes, benzene, toluene when results were examined with respect to the amount of aromatic added to water to produce the LD/sub 50/. The importance of determining the concentrations of compounds dissolved in water when conducting any investigation of biological effects of water pollutants is stressed.

  6. Use of New Water Soluble Surface Film—Forming Material to Reduce Ammonia Loss from Water Solution

    Institute of Scientific and Technical Information of China (English)

    YINBIN; SHENRENFANG; 等

    1996-01-01

    A new water soluble surface film-forming material was developed and its effect on reducing ammonia volatilization from an alkaline solution was investigated in laboratory,Results showed that the new film formed by the material was not only more effective in reducing ammonia loss than any other films tested but also much cheaper.The optimum amount of addition of the new film-forming material was about 10times the theoretical amount to form a monomolecular film.Under the experimental conditions,the new film could effectively depress the ammonia volatilization for at least 6 days.The cumulative ammonia loss rates for different films were fitted to a simple logistic equation ,and some important parameters such as the cumulative loss,and the maximum and average volatilization rates were calculated.The effect of different films could be,therefore,compared quantitatively,indicating the new film was most effective in depressing ammonia volatilization.

  7. Solubility of natural gases in water under high pressure; Solubilite des gaz naturels dans l`eau a pression elevee

    Energy Technology Data Exchange (ETDEWEB)

    Dhima, A.

    1998-10-08

    Under high pressure (up to 1200 bar) and high temperature (up to 200 deg C) petroleum reservoir conditions the hydrocarbon-water mutual solubilities may become important. Under such conditions, the prediction of hydrocarbon water solubilities is a challenge for petroleum engineers. Indeed, very few studies have been done ar pressures higher that 700 bars. New solubility data for methane, ethane, n-butane, CO{sub 2} and their mixtures in pure water were obtained at 344.25 K and from 2.5 to 100 MPa. The results agree very well with those of the literature in the case of pure hydrocarbons in water, but differ for the hydrocarbon mixtures. A rigorous thermodynamic analysis allows the elaboration of a model that combines a cubic equation of state (Peng-Robinson with k{sub ij} given in literature) with the Henry`s law approach. The (P,T) functional form of Henry`s constant is given by the Krichevsky-Kasarnovsky equation which involves two important parameters: partial molar volume at infinite dilution and Henry`s constant at the vapour pressure of water. For a given solute both parameters are only functions of temperature. A critical selection of binary solubility data for a large number of solutes has been used as a basis for a new correlation for calculating both this partial molar volume and the corresponding Henry`s constants as a function of temperature. (author) 169 refs.

  8. 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.

  9. The application of water-soluble ruthenium catalysts for the hydrogenation of the dichloromethane soluble fraction of fast pyrolysis oil and related model compounds in a two phase aqueous-organic system

    NARCIS (Netherlands)

    Mahfud, F.H.; Bussemaker, S.; Kooi, B.J.; ten Brink, Gert; Heeres, H.J.

    2007-01-01

    The hydrogenation of a dichloromethane soluble fraction of flash pyrolysis oil (bio-oil, BO), obtained by treatment of BO with a water–dichloromethane solvent mixture, was investigated using a water-soluble homogeneous ruthenium catalyst (RuCl3·3H2O/tris(m-sulfonatophenyl)phosphine, TPPTS). The

  10. IUPAC-NIST Solubility Data Series. 101. Alcohols + Hydrocarbons + Water Part 3. C1-C3 Alcohols + Aromatic Hydrocarbons

    Science.gov (United States)

    Oracz, Paweł; Góral, Marian; Wiśniewska-Gocłowska, Barbara; Shaw, David G.; Mączyński, Andrzej

    2016-09-01

    The mutual solubilities and related liquid-liquid equilibria for 11 ternary systems of C1-C3 alcohols with aromatic hydrocarbons and water are exhaustively and critically reviewed. Reports of experimental determination of solubility that appeared in the primary literature prior to the end of 2012 are compiled. For nine systems, sufficient data are available (two or more independent determinations) to allow critical evaluation. All new data are expressed as mass percent and mole fraction as well as the originally reported units. In addition to the standard evaluation criteria used throughout the Solubility Data Series, an additional criterion was used for each of the evaluated systems. These systems include one binary miscibility gap in the hydrocarbon + water subsystem. The binary tie lines were compared with the recommended values published previously.

  11. Solubility of 1:1 Alkali Nitrates and Chlorides in Near-Critical and Supercritical Water : 1 Alkali Nitrates and Chlorides in Near-Critical and Supercritical Water

    NARCIS (Netherlands)

    Leusbrock, Ingo; Metz, Sybrand J.; Rexwinkel, Glenn; Versteeg, Geert F.

    2009-01-01

    To increase the available data oil systems containing supercritical water and inorganic compounds, all experimental setup was designed to investigate the solubilities of inorganic compounds Ill supercritical water, In this work, three alkali chloride salts (LiCl, NaCl, KCl) and three alkali nitrate

  12. Water-soluble gases as partitioning tracers to investigate the pore volume?transmissivity correlation in a fracture

    Science.gov (United States)

    Lunati, Ivan; Kinzelbach, Wolfgang

    2004-11-01

    Hydraulically equivalent fractures may show striking differences when a gas-migration experiment is performed because of the different correlations between transmissivity, pore volume and entry pressure. We numerically simulate gas migration between injection and extraction boreholes in a parallel plate fracture with a heterogeneous fault gouge, in a rough-walled fracture filled with homogeneous material, and in a rough-walled empty fracture. The parallel plate model and the empty model clearly show the existence of preferential paths; for high variance of the transmissivity field, gas flow takes place only in few discrete channels separated by water-saturated regions. In contrast, in the fracture filled with homogeneous fault gouge, the gas saturation is continuous and more uniformly distributed. It appears a fundamental issue to be able to discriminate in situ among conceptual models that can yield such a different gas-saturation distribution. As in practice, the saturation distribution cannot be directly observed, tracer experiments are performed to characterize a fracture. For these reasons, we simulate the transport of tracers, which are added to the gas phase as soon as quasi-steady saturation distribution and extraction rate are achieved, and we compare the breakthrough curves obtained assuming different models. Our numerical simulations suggest that discrimination among the models on the basis of single-tracer tests is unlikely. A better tool to investigate fracture properties is provided by a gas-tracer test, in which a cocktail of gases with different water solubility is employed. These gases behave as partitioning tracers and allow us to estimate the gas saturation in the fracture. Indeed, by comparison of the residence-time distributions of different gases, we are able to compute a streamline effective saturation, which is an excellent estimate of fracture saturation. In addition, the streamline effective saturation curve contains information that is

  13. Partitioning of water soluble organic carbon in three sediment size fractions: Effect of the humic substances

    Institute of Scientific and Technical Information of China (English)

    SUN Liying; SUN Weiling; NI Jinren

    2009-01-01

    Water soluble organic carbon (WSOC) in sediments plays an important role in transference and transformation of aquatic pollutants. This article investigated the inherent mechanisms of how sediemnt grain size affect the partitioning coeffcient (k) of WSOC. Influences of NaOH extracted humic substances were particularly focused on. Sediments were sampled from two cross-sections of the middle Yellow River and sieved into three size fractions (< 63 μm, 63-100 μm, and 100--300 μm). The total concentration of WSOC in sediments (CWSOC) and k were estimated using multiple water-sediment ratio experiments. Results show that CWSOC ranges from 0.012 to 0.022 mg/g, while k ranges from 0.8 to 3.9 L/kg. Correlations between the spectrum characteristics of NaOH extracted humic substances and k were analyzed. Strong positive correlations are determined between k and the aromaticity indicators of NaOH extracted humic substances in different sediment size fractions. Comparing with finer fractions (< 63 μm), k is higher in larger size fractions (63--100 and 100--300 μm) related to higher aromaticity degree of NaOH extracted humic substances mostly. While negative relationship between k and the area ratio of fourier transform infrared spectroscopy (FT-IR) at 3400 and 1430 cm-1 implied that the lowest k was related to the highest concentration of the acidic humic groups in particles < 63 μm. WSOC in finer fractions (< 63 μm) is likely to enter into pore water, which may further accelerate the transportation of aquatic contaminants from sediment to water.

  14. 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.

  15. Improved prediction of octanol-water partition coefficients from liquid-solute water solubilities and molar volumes

    Science.gov (United States)

    Chiou, C.T.; Schmedding, D.W.; Manes, M.

    2005-01-01

    A volume-fraction-based solvent-water partition model for dilute solutes, in which the partition coefficient shows a dependence on solute molar volume (V??), is adapted to predict the octanol-water partition coefficient (K ow) from the liquid or supercooled-liquid solute water solubility (Sw), or vice versa. The established correlation is tested for a wide range of industrial compounds and pesticides (e.g., halogenated aliphatic hydrocarbons, alkylbenzenes, halogenated benzenes, ethers, esters, PAHs, PCBs, organochlorines, organophosphates, carbamates, and amidesureas-triazines), which comprise a total of 215 test compounds spanning about 10 orders of magnitude in Sw and 8.5 orders of magnitude in Kow. Except for phenols and alcohols, which require special considerations of the Kow data, the correlation predicts the Kow within 0.1 log units for most compounds, much independent of the compound type or the magnitude in K ow. With reliable Sw and V data for compounds of interest, the correlation provides an effective means for either predicting the unavailable log Kow values or verifying the reliability of the reported log Kow data. ?? 2005 American Chemical Society.

  16. Formulation and particle size reduction improve bioavailability of poorly water-soluble compounds with antimalarial activity.

    Science.gov (United States)

    Wang, Hongxing; Li, Qigui; Reyes, Sean; Zhang, Jing; Xie, Lisa; Melendez, Victor; Hickman, Mark; Kozar, Michael P

    2013-01-01

    Decoquinate (DQ) is highly effective at killing malaria parasites in vitro; however, it is extremely insoluble in water. In this study, solid dispersion method was used for DQ formulation which created a suitable physical form of DQ in aqueous phase for particle manipulation. Among many polymers and surfactants tested, polyvinylpyrrolidone 10, a polymer, and L- α -phosphatidylcholine or polysorbate, two surfactants, were chosen as DQ formulation components. The formulation particles were reduced to a mean size between 200 to 400 nm, which was stable in aqueous medium for at least three weeks. Pharmacokinetic (PK) studies showed that compared to DQ microparticle suspension, a nanoparticle formulation orally dosed to mice showed a 14.47-fold increase in area under the curve (AUC) of DQ plasma concentration and a 4.53-fold increase in AUC of DQ liver distribution. WR 299666, a poorly water-soluble compound with antimalarial activity, was also tested and successfully made into nanoparticle formulation without undergoing solid dispersion procedure. We concluded that nanoparticles generated by using appropriate formulation components and sufficient particle size reduction significantly increased the bioavailability of DQ and could potentially turn this antimalarial agent to a therapeutic drug.

  17. Microbial oxidation of soluble sulfide in produced water from the Bakkeen Sands

    Energy Technology Data Exchange (ETDEWEB)

    Gevertz, D.; Zimmerman, S. [Agouron Institute, La Jolla, CA (United States); Jenneman, G.E. [Phillips Petroleum Company, Bartlesville, OK (United States)] [and others

    1995-12-31

    The presence of soluble sulfide in produced water results in problems for the petroleum industry due to its toxicity, odor, corrosive nature, and potential for wellbore plugging. Sulfide oxidation by indigenous nitrate-reducing bacteria (NRB) present in brine collected from wells at the Coleville Unit (CVU) in Saskatchewan, Canada, was investigated. Sulfide oxidation took place readily when nitrate and phosphate were added to brine enrichment cultures, resulting in a decrease in sulfide levels of 99-165 ppm to nondetectable levels (< 3.3 ppm). Produced water collected from a number of producing wells was screened to determine the time required for complete sulfide oxidation, in order to select candidate wells for treatment. Three wells were chosen, based on sulfide removal in 48 hours or less. These wells were treated down the backside of the annulus with a solution containing 10 mM KNO{sub 3} and 100 {mu}M NaH{sub 2}PO{sub 4}. Following a 24- to 72-hour shut-in, reductions in pretreatment sulfide levels of greater than 90% were observed for two of the wells, as well as sustained sulfide reductions of 50% for at least two days following startup. NRB populations in the produced brine were observed to increase significantly following treatment, but no significant increases in sulfate-reducing bacteria were observed. These results demonstrate the technical feasibility of stimulating indigenous populations of NRB to remediate and control sulfide in produced brine.

  18. Extraction of water-soluble polysaccharide and the antioxidant activity from Semen cassiae

    Directory of Open Access Journals (Sweden)

    Changjian Liu

    2014-12-01

    Full Text Available Water-soluble polysaccharide was isolated from Semen cassiae using water for extraction and ethanol for deposition. The optimized conditions for polysaccharide isolation by orthogonal experiments were a sample to liquid ratio of 1:30 at 80°C for 3.5 hours; the yield of polysaccharide from Semen cassiae under these conditions was 5.46%. Different polysaccharides (SCPW-1, SCPW-2, SCPW-3, SCPW-4, SCPW-5, SCPS-1, SCPS-2 were obtained from the extract (i.e., crude polysaccharide by DEAE-cellulose column chromatography. The polysaccharides obtained showed different structures by Fourier transform infrared therein the five elected from the seven kinds separated. The antioxidant activities of the extract were evaluated. The scavenging rates of the present extract on hydroxyl and superoxide were 43.32% and 64.97%, respectively, at a concentration of polysaccharide of 94.03 μg/mL, which was better than vitamin C at the same concentration. The scavenging rate of the present extract on 1,1-diphenyl-2-picrylhydrazyl was 13.33% at a polysaccharide concentration of 94.03 μg/mL, which was less than vitamin C at the same concentration.

  19. Analysis of Water Soluble Vitamins (Thiamine, Nicotinamide and Pyridoxine in Fortified Infant Food Products by Hplc

    Directory of Open Access Journals (Sweden)

    Narjis Naz

    2016-05-01

    Full Text Available The present study provides information about the levels of fortification of three water soluble vitamins i.e. thiamine (B1, nicotinamide (B3 and pyridoxine (B6 in a variety of foodstuffs include milk products and cereals for young children. Food fortification is key implement for improving health of the growing children. Twenty food samples were chosen for analysis because of their common utilization in the local area. The vitamin concentrations were determined by high performance liquid chromatography with C18 column with a gradient of mobile phase made of water and acetonitrile and a diode array detector set at 280 nm. The thiamine content investigated in the samples ranging from 268 µg/mL to 3 µg/ml, nicotinamide content was from 41 µg/ml to 1 µg/mL while the pyridoxine level was in between 412 µg/mL to 20 µg/mL. Detection and Quantification of compounds were attained by comparing their retention times with standard reference materials and on the basis the off peak area match against those of a standard. The method used, offer excellent linearity with r2 ≥ 0.994, detection limits, reproducibility, and analyte recovery.

  20. Irreversible catalyst activation enables hyperpolarization and water solubility for NMR signal amplification by reversible exchange.

    Science.gov (United States)

    Truong, Milton L; Shi, Fan; He, Ping; Yuan, Bingxin; Plunkett, Kyle N; Coffey, Aaron M; Shchepin, Roman V; Barskiy, Danila A; Kovtunov, Kirill V; Koptyug, Igor V; Waddell, Kevin W; Goodson, Boyd M; Chekmenev, Eduard Y

    2014-12-04

    Activation of a catalyst [IrCl(COD)(IMes)] (IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene; COD = cyclooctadiene)] for signal amplification by reversible exchange (SABRE) was monitored by in situ hyperpolarized proton NMR at 9.4 T. During the catalyst-activation process, the COD moiety undergoes hydrogenation that leads to its complete removal from the Ir complex. A transient hydride intermediate of the catalyst is observed via its hyperpolarized signatures, which could not be detected using conventional nonhyperpolarized solution NMR. SABRE enhancement of the pyridine substrate can be fully rendered only after removal of the COD moiety; failure to properly activate the catalyst in the presence of sufficient substrate can lead to irreversible deactivation consistent with oligomerization of the catalyst molecules. Following catalyst activation, results from selective RF-saturation studies support the hypothesis that substrate polarization at high field arises from nuclear cross-relaxation with hyperpolarized (1)H spins of the hydride/orthohydrogen spin bath. Importantly, the chemical changes that accompanied the catalyst's full activation were also found to endow the catalyst with water solubility, here used to demonstrate SABRE hyperpolarization of nicotinamide in water without the need for any organic cosolvent--paving the way to various biomedical applications of SABRE hyperpolarization methods.

  1. 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.

  2. Blood compatibility of thermoplastic polyurethane membrane immobilized with water-soluble chitosan/dextran sulfate.

    Science.gov (United States)

    Lin, Wen-Ching; Yu, Da-Guang; Yang, Ming-Chien

    2005-08-01

    Water-soluble chitosan (WSC)/dextran sulfate (DS) was immobilized onto the surface of thermoplastic polyurethane (TPU) membrane after ozone-induced graft polymerization of poly(acrylic acid) (PAA). The surface was characterized with contact angle measurement and X-ray photoelectron spectroscopy (XPS). The adsorption of human plasma fibrinogen (HPF) followed the Langmuir adsorption isotherm. The results showed that the surface density of peroxides generated and poly(acrylic acid) (PAA) grafted reached the maximum value at 20 min of ozone treatment. It was found that the WSC- and DS-immobilized amount increased with pH and the molecular weight of WSC. The membrane/water interfacial free energy increased with PAA-grafting and WSC/DS-immobilization, indicating the increasing wettability of TPU membrane. The adsorption of HPF on TPU-WSC/DS membranes could be effectively curtailed and exhibited unfavorable adsorption. Moreover, WSC/DS immobilization could effectively reduce platelet adhesion and prolong the blood coagulation time, thereby membrane improving blood compatibility of TPU membrane. In addition, the in vitro cytotoxicity test of PEC modification was non-cytotoxic according to much low growth inhibition of L929 fibroblasts. Furthermore, TPU-WSC/DS membranes exhibited higher cell viability than native TPU membrane.

  3. Soluble microbial products in pilot-scale drinking water biofilters with acetate as sole carbon source.

    Science.gov (United States)

    Zhang, Ying; Ye, Chengsong; Gong, Song; Wei, Gu; Yu, Xin; Feng, Lin

    2013-04-01

    A comprehensive study on formation and characteristics of soluble microbial products (SMP) during drinking water biofiltration was made in four parallel pilot-scale ceramic biofilters with acetate as the substrate. Excellent treatment performance was achieved while microbial biomass and acetate carbon both declined with the depth of filter. The SMP concentration was determined by calculating the difference between the concentration of dissolved organic carbon (DOC), biodegradable dissolved organic carbon (BDOC) and acetate carbon. The results revealed that SMP showed an obvious increase from 0 to 100 cm depth of the filter. A rising specific ultraviolet absorbance (SUVA) was also found, indicating that benzene or carbonyl might exist in these compounds. SMP produced during this drinking water biological process were proved to have weak mutagenicity and were not precursors of by-products of chlorination disinfection. The volatile parts of SMP were half-quantity analyzed and most of them were dicarboxyl acids, others were hydrocarbons or benzene with 16-17 carbon atoms.

  4. Water Soluble Usnic Acid-Polyacrylamide Complexes with Enhanced Antimicrobial Activity against Staphylococcus epidermidis

    Directory of Open Access Journals (Sweden)

    Iolanda Francolini

    2013-04-01

    Full Text Available Usnic acid, a potent antimicrobial and anticancer agent, poorly soluble in water, was complexed to novel antimicrobial polyacrylamides by establishment of strong acidic-base interactions. Thermal and spectroscopic analysis evidenced a molecular dispersion of the drug in the polymers and a complete drug/polymer miscibility for all the tested compositions. The polymer/drug complexes promptly dissolved in water and possessed a greater antimicrobial activity against Staphylococcus epidermidis than both the free drug and the polymer alone. The best results were obtained with the complex based on the lowest molecular weight polymer and containing a low drug content. Such a complex showed a larger inhibition zone of bacterial growth and a lower minimum inhibitory concentration (MIC with respect to usnic acid alone. This improved killing effect is presumably due to the reduced size of the complexes that allows an efficient cellular uptake of the antimicrobial complexes. The killing effect extent seems to be not significantly dependent on usnic acid content in the samples.

  5. Water-soluble PEGylated silicon nanoparticles and their assembly into swellable nanoparticle aggregates

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zejing; Li, Yejia; Zhang, Boyu; Purkait, Tapas [Tulane University, Department of Chemistry (United States); Alb, Alina [Tulane University, Department of Physics and Engineering Physics (United States); Mitchell, Brian S. [Tulane University, Department of Chemical and Biomolecular Engineering (United States); Grayson, Scott M.; Fink, Mark J., E-mail: fink@tulane.edu [Tulane University, Department of Chemistry (United States)

    2015-01-15

    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.

  6. Solubility controls on aluminum in drinking water at relatively low and high pH.

    Science.gov (United States)

    Kvech, Steve; Edwards, Marc

    2002-10-01

    Potential control of soluble aluminum in drinking water by formation of solids other than Al(OH)3 was examined. At pHs below 6.0, Al(+3) solids containing sulfate, silica or potassium are thermodynamically favored versus amorphous Al(OH)3; however, in this work no evidence could be obtained that solids other than Al(OH)3 would form in practice. At pHs above 9, aluminum and magnesium were discovered to form complex solid phases of approximate composition AlMg2(OH)7, AlMg2SiO2(OH)7 or Al(SiO2)2(OH)3 dependent on circumstance. Formation of these solids provide a mechanistic explanation for enhancements to precipitative softening obtained in practice by dosing Al(+3) salts; that is, improved flocculation/settling and removal of silica from water that interferes with calcium precipitation. The solids also maintain residual aluminum below regulatory guidelines at high pH > 9.5.

  7. Water Soluble Organic Compounds over the Eastern Mediterranean: Study of their occurrence and sources

    Science.gov (United States)

    Tziaras, T.; Spyros, A.; Mandalakis, M.; Apostolaki, M.; Stephanou, E. G.

    2010-05-01

    Fine marine aerosols influence the climate system by acting as cloud condensation nuclei (CCN) in the atmosphere. The organic chemical composition and origin of the marine fine particulate matter are still largely unknown, because of the insufficient reports on in situ studies, the large variability in the emission from the sea, from the complex transfer of gases and particles at the air-sea interface, and the transport of aerosol particles from very distant sources. As important processes of formation of marine organic aerosol production we consider: transport of terrestrial particles, secondary organic aerosol (SOA) formation from the oxidation of biogenic dimethyl-sulfide (DMS), and biogenic particle emissions through sea spray. Specific compounds related to the above-mentioned processes have been proposed as molecular markers: e.g. n-alkanoic acids and n-alkanes (terrestrial particles), levoglucosan (biomass burning aerosol), aminoacids (biological terrestrial or marine particles), methanesulphonate (MSA) (DMS oxidation), C8 and C9 dicarboxylic acids and oxo-carboxylic acids (marine SOA) and other short-chain dicarboxylic acids (marine or terrestrial SOA), and humic-like compounds (emission of marine organic carbon). In our study, we made an effort to characterize the water-soluble organic fraction of marine aerosols collected at a background sampling site of Eastern Mediterranean (Finokalia, N35o20', E25o40', Island of Crete, Greece). The sampling period was 2007-2008. In order to identify and quantify the water-soluble organic compounds of marine aerosols determined in the present study we have used gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS) and nuclear magnetic resonance spectroscopy (NMR) and ion chromatography (IC). The origin of air masses arriving in the study area was studied by using backward trajectories calculation (NOAA HYSPLIT Model). In addition, we have used the "MODIS fire products" for fire

  8. Experimental study of Ni solubility in sulphidic groundwater and cement water under anoxic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, T.; Vuorinen, U.; Kekki, T.; Aalto, H. [VTT Chemical Technology, Espoo (Finland)

    2001-06-01

    The nickel solubility was studied during a 177-day period under anoxic conditions in three types of waters: a synthetic reference groundwater (OL-SR), a natural Olkiluoto groundwater (PVA2), and a cement-conditioned groundwater (C-PVA2). To each water, nickel, ferrous iron and sulphide were added yielding eight combinations of, approximately, the following initial concentrations: nickel: 1.0x10{sup -6} and 1.0x10{sup -3} mol/L, ferrous iron: 1.8 10{sup -6} and 1.8x10{sup -5} mol/L, and sulphide: 3.1x10{sup -6} and 9.4x10{sup -5} mol/L. The concentrations of these elements in the natural groundwater PVA2 as well as in the cement-conditioned water C-PVA2 was insignificant. In the synthetic water, the nickel concentration was unchanged in all samples having a high initial nickel concentration of 1.0x10{sup -3} mol/L. In the samples with an initial low nickel concentration of 1.0x10{sup -6} mol/L, the sulphide content determined the final nickel concentration. Where the initial sulphide concentration was low, the nickel concentration remained at the level of 1.0x10{sup -6} mol/L, but the higher sulphide concentration caused the nickel concentration to drop to below 10{sup -8} mol/L. In the natural groundwater PVA2, the nickel concentration dropped to below 10{sup -4} mol/L in all samples with an initially high nickel concentration, and to values of roughly 10{sup -7} mol/L in samples with an initially low nickel content. In the cement-conditioned water, the nickel concentration reached a value of 3x10{sup -6} mol/L in samples with initial high nickel concentrations, and to a value of 1x10{sup -7} mol/L in samples with a low initial nickel content. The added amounts of iron and sulphide did not have any significant effect on the observed nickel solubility. The solid phases formed in the natural and synthetic groundwater were analyzed by XRD but could not be identified. In the case of cement-conditioned water the XRD analyses showed the presence of Ni(OH){sub 2} as well

  9. A study of lipid- and water-soluble arsenic species in liver of Northeast Arctic cod (Gadus morhua) containing high levels of total arsenic

    DEFF Research Database (Denmark)

    Sele, Veronika; Sloth, Jens Jørgen; Julshamn, Kale;

    2015-01-01

    In the present study liver samples (n = 26) of Northeast Arctic cod (Gadus morhua), ranging in total arsenic concentrations from 2.1 to 240 mg/kg liver wet weight (ww), were analysed for their content of total arsenic and arsenic species in the lipid-soluble and water-soluble fractions. The arsenic...... concentrations in the lipid fractions ranged from 1.8 to 16.4 mg As/kg oil of liver, and a linear correlation (r(2) = 0.80, p arsenic concentrations in liver and the total arsenic concentrations in the respective lipid fractions of the same livers. The relative proportion...... of arsenolipids was considerably lower in liver samples with high total arsenic levels (33-240 mg/kg ww), which contained from 3 to 7% of the total arsenic in the lipid-soluble fraction. In contrast liver samples with low arsenic concentrations (2.1-33 mg/kg ww) contained up to 50% of the total arsenic as lipid...

  10. Thin Films Formed from Conjugated Polymers with Ionic, Water-Soluble Backbones.

    Science.gov (United States)

    Voortman, Thomas P; Chiechi, Ryan C

    2015-12-30

    This paper compares the morphologies of films of conjugated polymers in which the backbone (main chain) and pendant groups are varied between ionic/hydrophilic and aliphatic/hydrophobic. We observe that conjugated polymers in which the pendant groups and backbone are matched, either ionic-ionic or hydrophobic-hydrophobic, form smooth, structured, homogeneous films from water (ionic) or tetrahydrofuran (hydrophobic). Mismatched conjugated polymers, by contrast, form inhomogeneous films with rough topologies. The polymers with ionic backbone chains are conjugated polyions (conjugated polymers with closed-shell charges in the backbone), which are semiconducting materials with tunable bad-gaps, not unlike uncharged conjugated polymers.

  11. Superwetting double-layer polyester materials for effective removal of both insoluble oils and soluble dyes in water.

    Science.gov (United States)

    Li, Bucheng; Wu, Lei; Li, Lingxiao; Seeger, Stefan; Zhang, Junping; Wang, Aiqin

    2014-07-23

    Inspired by the mussel adhesive protein and the lotus leaf, Ag-based double-layer polyester (DL-PET) textiles were fabricated for effective removal of organic pollutants in water. The DL-PET textiles are composed of a top superamphiphilic layer and a bottom superhydrophobic/superoleophilic layer. First, the PET textiles were modified with a layer of polydopamine (PDA) and deposited with Ag nanoparticles to form the PET@PDA@Ag textiles. The top superamphiphilic layer, formed by immobilizing Ag3PO4 nanoparticles on the PET@PDA@Ag textile, shows excellent visible-light photocatalytic activity. The bottom superhydrophobic/superoleophilic layer, formed by modifying the PET@PDA@Ag textile using dodecyl mercaptan, is mechanically, environmentally, and chemically very stable. The water-insoluble oils with low surface tension can penetrate both layers of the DL-PET textiles, while the water with soluble organic dyes can only selectively wet the top layer owing to their unique wettability. Consequently, the water-soluble organic contaminants in the collected water can be decomposed by the Ag3PO4 nanoparticles of the top layer under visible-light irradiation or even sunlight in room conditions. Thus, the DL-PET textiles can remove various kinds of organic pollutants in water including both insoluble oils and soluble dyes. The DL-PET textiles feature unique wettability, high oil/water separation efficiency, and visible-light photocatalytic activity.

  12. 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

  13. Sources and light absorption of water-soluble organic carbon aerosols in the outflow from northern China

    Science.gov (United States)

    Kirillova, E. N.; Andersson, A.; Han, J.; Lee, M.; Gustafsson, Ö.

    2014-02-01

    High loadings of anthropogenic carbonaceous aerosols in Chinese air influence the air quality for over one billion people and impact the regional climate. A large fraction (17-80%) of this aerosol carbon is water-soluble, promoting cloud formation and thus climate cooling. Recent findings, however, suggest that water-soluble carbonaceous aerosols also absorb sunlight, bringing additional direct and indirect climate warming effects, yet the extent and nature of light absorption by this water-soluble "brown carbon" and its relation to sources is poorly understood. Here, we combine source estimates constrained by dual carbon isotopes with light-absorption measurements of water-soluble organic carbon (WSOC) for a March 2011 campaign at the Korea Climate Observatory at Gosan (KCOG), a receptor station in SE Yellow Sea for the outflow from northern China. The mass absorption cross section at 365 nm (MAC365) of WSOC for air masses from N. China were in general higher (0.8-1.1 m2 g-1), than from other source regions (0.3-0.8 m2 g-1). However, this effect corresponds to only 2-10% of the radiative forcing caused by light absorption by elemental carbon. Radiocarbon constraints show that the WSOC in Chinese outflow had significantly higher fraction fossil sources (30-50%) compared to previous findings in S. Asia, N. America and Europe. Stable carbon (δ13C) measurements were consistent with aging during long-range air mass transport for this large fraction of carbonaceous aerosols.

  14. Synthesis and Characterization of A Novel Water-soluble Block Copolymer with A Rod-coil Structure

    Institute of Scientific and Technical Information of China (English)

    Zhijian Zhang; Wei Wei; Wei Huang

    2005-01-01

    @@ 1Introduction In this paper, a novel water-soluble block copolymer with rod-coil structures was prepared using polyfluorene (PF) as rod segment and polyethylene glycol (PEG) as coil segment in the main chain. A new but simple way of polycondensation ( shown in Scheme 1 ) was employed, compared with tedious atom transfer radical polymerization and ionic polymerization approaches.

  15. An Approach to New Water-soluble Oligo(ethylene glycol) Camptothecin Analogues by 1,3-Dipolar Cycloaddition

    Institute of Scientific and Technical Information of China (English)

    Chun Yan XU; Ming Zhi HUANG

    2006-01-01

    Combined with an effective copper-catalyzed triazole-forming reaction, a series of novel camptothecin derivatives were synthesized. Incorporating oligo(ethylene glycol) chains into the derivatives enhanced their water-solubility when compared to the parent compound (up to 55-fold).

  16. Enhanced in vitro and in vivo cellular imaging with green tea coated water-soluble iron oxide nanocrystals

    NARCIS (Netherlands)

    Xiao, Lisong; Mertens, Marianne; Wortmann, Laura; Kremer, Silke; Valldor, Martin; Lammers, Twan; Kiessling, Fabian; Mathur, Sanjay

    2015-01-01

    Fully green and facile redox chemistry involving reduction of colloidal iron hydroxide (Fe(OH)3) through green tea (GT) polyphenols produced water-soluble Fe3O4 nanocrystals coated with GT extracts namely epigallocatechin gallate (EGCG) and epicatechin (EC). Electron donating polyphenols stoichiomet

  17. Water-soluble organic compounds (WSOCs) in PM2.5 and PM10 at a subtropical site of India

    Science.gov (United States)

    Khare, Puja; Baruah, B. P.; Rao, P. G.

    2011-11-01

    PM2.5 and PM10 samples collected at a suburban site of northeastern part of India have been analysed for particle mass, total carbon (TC), water-soluble total carbon (WSTC), water-soluble organic carbon (WSOC), water-soluble inorganic carbon (WSIC), organic acids (formic, acetic, proponoic and oxalic acids) along with inorganic ions (NO3-, SO42- and NH4-). Most of the PM10 consists of PM2.5 in the present site (ratio 54-74%). WSTC content in PM2.5 and PM10 corresponds to 21% and 16%, respectively, of their total particle masses. Thermo gravimetric analysis showed the presence of humic-like substances (16-22%) in particulate samples. Domestic heating and stagnant atmospheric conditions enhanced the levels of these carbonaceous compounds in PM2.5 and PM10 in winter. Qualitative estimation of various functional groups by Fourier transform infrared (FTIR) analysis indicates the presence of carboxylic, hydroxyl, aliphatic and aromatic hydrocarbons, amines and sulphurous compounds in these aerosols. Absolute principal component analysis applied on the aerosol data resolves four factors. These factors are associated with carbonaceous aerosols released from combustion of coal and wood, secondary inorganic and organic aerosols and water-soluble inorganic fraction.

  18. Mutual Solubility of MEG, Water and Reservoir Fluid: Experimental Measurements and Modeling using the CPA Equation of State

    DEFF Research Database (Denmark)

    Riaz, Muhammad; Kontogeorgis, Georgios; Stenby, Erling Halfdan

    2011-01-01

    . Prediction of mutual solubility of water, MEG and hydrocarbon fluids is important for the oil industry to ensure production and processing as well as to satisfy environmental regulations. The CPA equation of state has been successfully applied in the past to well defined systems containing associating...

  19. 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.

  20. Estimation of octanol/water partition coefficient and aqueous solubility of environmental chemicals using molecular fingerprints and machine learning methods

    Science.gov (United States)

    Octanol/water partition coefficient (logP) and aqueous solubility (logS) are two important parameters in pharmacology and toxicology studies, and experimental measurements are usually time-consuming and expensive. In the present research, novel methods are presented for the estim...