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Sample records for ezatiostat hydrochloride liposomes

  1. Multifunctional liposomes for nasal delivery of the anti-Alzheimer drug tacrine hydrochloride

    DEFF Research Database (Denmark)

    Corace, Giuseppe; Angeloni, Cristina; Malaguti, Marco

    2014-01-01

    . This approach was chosen in order to obtain at the same time two positive results: an enhanced drug permeation through nasal mucosa and a concomitant neuroprotective effect. Several liposome formulations were prepared using the Reverse Phase Evaporation technique followed by membrane filter extrusion......Abstract The purpose of this study was the development of multifunctional liposomes for nasal administration of tacrine hydrochloride. Liposomes were prepared using traditional excipients (cholesterol and phosphatidylcholine), partly enriched with α-tocopherol and/or Omega3 fatty acids...

  2. Development and Characterization of Liposomal Doxorubicin Hydrochloride with Palm Oil

    Directory of Open Access Journals (Sweden)

    Bahareh Sabeti

    2014-01-01

    Full Text Available The usage of natural products in pharmaceuticals has steadily seen improvements over the last decade, and this study focuses on the utilization of palm oil in formulating liposomal doxorubicin (Dox. The liposomal form of Dox generally minimizes toxicity and enhances target delivery actions. Taking into account the antiproliferative and antioxidant properties of palm oil, the aim of this study is to design and characterize a new liposomal Dox by replacing phosphatidylcholine with 5% and 10% palm oil content. Liposomes were formed using the freeze_thaw method, and Dox was loaded through pH gradient technique and characterized through in vitro and ex vivo terms. Based on TEM images, large lamellar vesicles (LUV were formed, with sizes of 438 and 453 nm, having polydispersity index of 0.21 ± 0.8 and 0.22 ± 1.3 and zeta potentials of about −31 and −32 mV, respectively. In both formulations, the entrapment efficiency was about 99%, and whole Dox was released through 96 hours in PBS (pH = 7.4 at 37°C. Comparing cytotoxicity and cellular uptake of LUV with CaelyxR on MCF7 and MDA-MBA 231 breast cancer cell lines indicated suitable uptake and lower IC50 of the prepared liposomes.

  3. Protection of the organism with 2'-deoxycytidine hydrochloride encapsulated in liposomes, in the process of experimental radioprotective chemotherapy with cytosine arabinoside

    International Nuclear Information System (INIS)

    Bukhman, V.M.; Bekman, E.M.; Koval'skaya, N.I.

    1986-01-01

    The development of methods of selective protection of the organism from the toxic and immunodepressive effect of cytostatics is directed toward improvement of the results of the therapy of malignant neoplasms. In this work, the authors demonstrate the promise of the use of liposomes as a phagocytizable carrier for the protector substance, on the model of developing T-cell lymphoma EL4 of mice. The production of liposomes and 2'-Deoxycytidine hydrochloride encapsulated in liposomes is discussed

  4. Preparation of a Sustained-Release Nebulized Aerosol of R-terbutaline Hydrochloride Liposome and Evaluation of Its Anti-asthmatic Effects via Pulmonary Delivery in Guinea Pigs.

    Science.gov (United States)

    Li, Qingrui; Zhan, Shuyao; Liu, Qing; Su, Hao; Dai, Xi; Wang, Hai; Beng, Huimin; Tan, Wen

    2018-01-01

    An aerosolized liposome formulation for the pulmonary delivery of an anti-asthmatic medication was developed. Asthma treatment usually requires frequent administration of medication for a sustained bronchodilator response. Liposomes are known for their sustained drug release capability and thus would be a suitable delivery system for prolonging the therapeutic effect of anti-asthmatic medication. Liposomes prepared by thin film hydration were loaded with a model drug, R-terbutaline hydrochloride(R-TBH), using an ammonium sulfate-induced transmembrane electrochemical gradient. This technique provided an encapsulation efficiency of up to 71.35% and yielded R-TBH liposomes with a particle size of approximately 145 ± 20 nm. According to stability studies, these R-TBH liposomes should be stored at 4°C before usage. Compared to R-TBH solution, which showed 90.84% release within 8 h, liposomal R-TBH had a cumulative release of 73.53% at 37°C over 192 h. A next generation impactor (NGI) was used to analyze the particle size distribution in the lungs of R-TBH liposome aerosol in vitro at 5°C. The therapeutic efficacy of the nebulized aerosol of the R-TBH liposomes was assessed via pulmonary delivery in guinea pigs. The results showed that, compared to the R-TBH solution group, the R-TBH liposome group had a prolonged anti-asthma effect.

  5. Pegylated Liposomal Irinotecan Hydrochloride Trihydrate for Treating Pancreatic Cancer After Gemcitabine: An Evidence Review Group Perspective of a NICE Single Technology Appraisal.

    Science.gov (United States)

    Fleeman, Nigel; Abdulla, Ahmed; Bagust, Adrian; Beale, Sophie; Richardson, Marty; Stainthorpe, Angela; Boland, Angela; Kotas, Eleanor; McEntee, Joanne; Palmer, Daniel

    2018-03-01

    The National Institute for Health and Care Excellence (NICE) invited the manufacturer (Shire Pharmaceuticals) of pegylated liposomal irinotecan hydrochloride trihydrate (liposomal irinotecan) to submit clinical and cost-effectiveness evidence for its use in combination with 5-fluorouracil (5-FU) and folic acid/leucovorin (LV) for treating patients with pancreatic cancer following prior treatment with gemcitabine as part of the institute's Single Technology Appraisal process. The Liverpool Reviews and Implementation Group at the University of Liverpool was commissioned to act as the Evidence Review Group (ERG). This article presents a summary of the company's evidence, the ERG review and the resulting NICE guidance (TA440), issued on 26 April 2017. Clinical evidence for liposomal irinotecan + 5-FU/LV versus 5-FU/LV was derived from 236 patients with metastatic pancreatic cancer in the multinational, open-label, randomised controlled NAPOLI-1 trial. Results from analyses of progression-free survival and overall survival showed statistically significant improvements for patients treated with liposomal irinotecan + 5-FU/LV compared with those treated with 5-FU/LV. However, 5-FU/LV alone is rarely used in National Health Service clinical practice for patients with metastatic pancreatic cancer previously treated with gemcitabine. The company, ERG and Appraisal Committee (AC) all agreed that oxaliplatin + 5-FU/LV is the most commonly used treatment. Oxaliplatin + 5-FU/LV was compared with 5-FU/LV in two trials identified by the company. However, the company and the ERG both considered attempts to compare the efficacy of liposomal irinotecan + 5-FU/LV with oxaliplatin + 5-FU/LV to be methodologically flawed; not only was there heterogeneity between trials and their populations but also the proportional hazards assumption required to conduct a robust indirect treatment comparison (ITC) was violated. Nonetheless, data derived from an ITC were used to inform the

  6. Oral Ezatiostat HCl (TLK199) and Myelodysplastic syndrome: a case report of sustained hematologic response following an abbreviated exposure.

    Science.gov (United States)

    Quddus, Fahd; Clima, Jessica; Seedham, Helen; Sajjad, Ghulam; Galili, Naomi; Raza, Azra

    2010-04-23

    Treatment options for patients with lower risk non-del(5q) myelodysplastic syndromes (MDS) who fail erythroid stimulating agents are restricted to one of the hypomethylating drugs with an expected response rate of approximately 50%. Ezatiostat HCl, an agent with the potential for producing multi-lineage responses in this population is currently in clinical investigation phase. This case report describes a 77 year old male who received less than two cycles of therapy with ezatiostat HCl which had to be aborted due to intolerable side effects, but which produced a sustained normalization of all three blood counts. This trilineage response has now lasted for more than a year. Interestingly, the patient began with a del(5q) abnormality and responded briefly to lenalidomide. Upon relapse of the anemia, a bone marrow showed the disappearance of the del(5q) but the appearance of a new clonal abnormality t(2;3). Given that the patient had a complete cytogenetic response to a truncated exposure to lenalidomide followed by a trilineage response to an even briefer course of ezatiostat HCl suggests a potential role for ezatiostat HCl in del(5q) patients who relapse following lenalidomide.

  7. Liposomal Drug Product Development and Quality: Current US Experience and Perspective.

    Science.gov (United States)

    Kapoor, Mamta; Lee, Sau L; Tyner, Katherine M

    2017-05-01

    Research in the area of liposomes has grown substantially in the past few decades. Liposomes are lipid bilayer structures that can incorporate drug substances to modify the drug's pharmacokinetic profile thereby improving drug delivery. The agency has received over 400 liposomal drug product submissions (excluding combination therapies), and there are currently eight approved liposomal drug products on the US market. In order to identify the pain points in development and manufacturing of liposomal drug products, a retrospective analysis was performed from a quality perspective on submissions for new and generic liposomal drug products. General analysis on liposomal drug product submissions was also performed. Results indicated that 96% of the submissions were Investigational New Drug (IND) applications, 3% were New Drug Applications (NDAs), and the remaining 1% was Abbreviated New Drug Applications (ANDAs). Doxorubicin hydrochloride was the most commonly used drug substance incorporated into the liposomes (31%). The majority of the liposomal products were administered via intravenous route (84%) with cancer (various types) being the most common indication (63%). From a quality perspective, major challenges during the development of liposomal drug products included identification and (appropriate) characterization of critical quality attributes of liposomal drug products and suitable control strategies during product development. By focusing on these areas, a faster and more efficient development of liposomal drug products may be achieved. Additionally, in this way, the drug review process for such products can be streamlined.

  8. Butriptyline Hydrochloride and Imipramine Hydrochloride in the ...

    African Journals Online (AJOL)

    used tricyclic antidepressants, imipramine hydrochloride, was undertaken in 28 patients suffering from non-psychotic depression in a doubleblind trial. Three criteria-side-effects, depression and anxiety-were observed at each visit. The scoring ...

  9. Cartap Hydrochloride Poisoning.

    Science.gov (United States)

    Kalyaniwala, Kimmin; Abhilash, Kpp; Victor, Peter John

    2016-08-01

    Cartap hydrochloride is a moderately hazardous nereistoxin insecticide that is increasingly used for deliberate self-harm in India. It can cause neuromuscular weakness resulting in respiratory failure. We report a patient with 4% Cartap hydrochloride poisoning who required mechanical ventilation for 36-hours. He recovered without any neurological deficits. We also review literature on Cartap hydrochloride poisoning. © Journal of the Association of Physicians of India 2011.

  10. Liposome-encapsulated chemotherapy

    DEFF Research Database (Denmark)

    Børresen, B.; Hansen, A. E.; Kjær, A.

    2018-01-01

    Cytotoxic drugs encapsulated into liposomes were originally designed to increase the anticancer response, while minimizing off-target adverse effects. The first liposomal chemotherapeutic drug was approved for use in humans more than 20years ago, and the first publication regarding its use...... to inherent issues with the enhanced permeability and retention effect, the tumour phenomenon which liposomal drugs exploit. This effect seems very heterogeneously distributed in the tumour. Also, it is potentially not as ubiquitously occurring as once thought, and it may prove important to select patients...... not resolve the other challenges that liposomal chemotherapy faces, and more work still needs to be done to determine which veterinary patients may benefit the most from liposomal chemotherapy....

  11. trimethylammoniumpropane-based Liposomes

    African Journals Online (AJOL)

    mechanisms to introduce therapeutic agents into the body. Currently, the ... Liposomes are biodegradable and non-toxic and can elicit both ... buffered saline by dissolving a vial in 40 ml phosphate ... vaccines were processed using copper grids to adsorb the .... time-dependent fluctuations in the intensity of scattered light ...

  12. Prednisolone phosphate-containing TRX-20 liposomes inhibit cytokine and chemokine production in human fibroblast-like synovial cells: a novel approach to rheumatoid arthritis therapy.

    Science.gov (United States)

    Harigai, Takashi; Hagiwara, Hitomi; Ogawa, Yumi; Ishizuka, Takanobu; Kaneda, Shinichi; Kimura, Junji

    2007-01-01

    To evaluate the potential of using prednisolone phosphate (PSLP)-containing 3,5-dipentadecyloxybenzamidine hydrochloride (TRX-20) liposomes to treat rheumatoid arthritis (RA), we examined their ability to bind human fibroblast-like synovial (HFLS) cells and their effects in these cells. To test for binding, Lissamine rhodamine B-1, 2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine (rhodamine)-labelled PSLP-containing TRX-20 liposomes were added to HFLS cells, and the fluorescence intensity of the rhodamine bound to the cells was evaluated. Rhodamine-labelled PSLP-containing liposomes without TRX-20 were used as a negative control. To evaluate the uptake of liposomes by the HFLS cells, we used TRX-20 liposomes containing 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS) and p-xylene-bis-pyridinium bromide (DPX), and observed the cells by fluorescence microscopy. The effects of the PSLP in TRX-20 liposomes on HFLS cells were assessed by the inhibition of the production of two inflammatory cytokines (interleukin 6 and granulocyte macrophage colony-stimulating factor) and one inflammatory chemokine (interleukin 8). The interaction of the PSLP-containing TRX-20 liposomes with HFLS cells was approximately 40 times greater than that of PSLP-containing liposomes without TRX-20. PSLP-containing TRX-20 liposomes bound to HFLS cells primarily via chondroitin sulfate. TRX-20 liposomes taken up by the cell were localized to acidic compartments. Furthermore, the PSLP-containing TRX-20 liposomes inhibited the production of the inflammatory cytokines and the chemokine more effectively than did the PSLP-containing liposomes without TRX-20. These results indicate that PSLP-containing TRX-20 liposomes show promise as a novel drug delivery system that could enhance the clinical use of glucocorticoids for treating RA.

  13. Boronated liposome development and evaluation

    International Nuclear Information System (INIS)

    Hawthorne, M.F.

    1995-01-01

    The boronated liposome development and evaluation effort consists of two separate tasks. The first is the development of new boron compounds and the synthesis of known boron species with BNCT potential. These compounds are then encapsulated within liposomes for the second task, biodistribution testing in tumor-bearing mice, which examines the potential for the liposomes and their contents to concentrate boron in cancerous tissues

  14. A novel drug delivery gel of terbinafine hydrochloride with high penetration for external use.

    Science.gov (United States)

    Yang, Yan; Ou, Rujing; Guan, Shixia; Ye, Xiaoling; Hu, Bo; Zhang, Yi; Lu, Shufan; Zhou, Yubin; Yuan, Zhongwen; Zhang, Jun; Li, Qing-Guo

    2015-12-01

    Terbinafine hydrochloride is an antifungal drug for onychomycosis. Poor permeability of its external preparation leads to poor curative effect. Transfersomes, also known as flexible liposome, could improve transmission of drug for local external use. Terbinafine hydrochloride-loaded liposome is expected to become a breakthrough on the treatment of onychomycosis. This study is aimed to prepare high skin penetration terbinafine hydrochloride transfersomes with high encapsulation efficiency, appropriate drug loading and good stability. Taking entrapment efficiency as the main indicator, the formulations and the processes of preparation were investigated. Transfersomes with different surfactants were prepared in the optimization processes, and the formulations were optimized through the transdermal test in vitro. As a result, a gel contained transfersomes was obtained with a brief evaluation. Its pharmacokinetic properties of going through the skin were studied by using the micro dialysis technology and liquid chromatography-mass spectrometry to assay the penetration behavior of terbinafine. Mean particle size of the terbinafine hydrochloride transfersomes was 69.6 ± 1.23 nm, and the entrapment efficiency was 95.4% ± 0.51. The content of the gel was 4.45 ± 0.15 mg/g. The accumulated permeation of the transfersomes gel in 12 h was 88.52 ± 4.06 µg cm -2 and the intracutaneous drug detention was 94.38 ± 5.26 µg cm -2 . The results of pharmacokinetic studies showed the C max and area under the curve (AUC) were apparently higher than the commercial cream. The terbinafine hydrochloride transfersomes was highly absorbed by the skin. The absorption rate was significantly higher than that of the commercial cream either in the transdermal test in vitro or in the pharmacokinetic studies in vivo.

  15. Use of liposomal bupivacaine in the postoperative management of posterior spinal decompression.

    Science.gov (United States)

    Grieff, Anthony N; Ghobrial, George M; Jallo, Jack

    2016-07-01

    OBJECTIVE The aim in this paper was to evaluate the efficacy of long-acting liposomal bupivacaine in comparison with bupivacaine hydrochloride for lowering postoperative analgesic usage in the management of posterior cervical and lumbar decompression and fusion. METHODS A retrospective cohort-matched chart review of 531 consecutive cases over 17 months (October 2013 to February 2015) for posterior cervical and lumbar spinal surgery procedures performed by a single surgeon (J.J.) was performed. Inclusion criteria for the analysis were limited to those patients who received posterior approach decompression and fusion for cervical or lumbar spondylolisthesis and/or stenosis. Patients from October 1, 2013, through December 31, 2013, received periincisional injections of bupivacaine hydrochloride, whereas after January 1, 2014, liposomal bupivacaine was solely administered to all patients undergoing posterior approach cervical and lumbar spinal surgery through the duration of treatment. Patients were separated into 2 groups for further analysis: posterior cervical and posterior lumbar spinal surgery. RESULTS One hundred sixteen patients were identified: 52 in the cervical cohort and 64 in the lumbar cohort. For both cervical and lumbar cases, patients who received bupivacaine hydrochloride required approximately twice the adjusted morphine milligram equivalent (MME) per day in comparison with the liposomal bupivacaine groups (5.7 vs 2.7 MME, p = 0.27 [cervical] and 17.3 vs 7.1 MME, p = 0.30 [lumbar]). The amounts of intravenous rescue analgesic requirements were greater for bupivacaine hydrochloride in comparison with liposomal bupivacaine in both the cervical (1.0 vs 0.39 MME, p = 0.31) and lumbar (1.0 vs 0.37 MME, p = 0.08) cohorts as well. None of these differences was found to be statistically significant. There were also no significant differences in lengths of stay, complication rates, or infection rates. A subgroup analysis of both cohorts of opiate-naive versus

  16. Liposome based radiosensitizer cancer therapy

    DEFF Research Database (Denmark)

    Pourhassan, Houman

    Liposome-encapsulated chemotherapeutics have been used in the treatment of a variety of cancers and are feasible for use as mono-therapeutics as well as for combination therapy in conjunction with other modalities. Despite widespread use of liposomal drugs in cancer patient care, insufficient drug...... biomolecules. By modulating the liposomal membrane, liposomes can become sensitive towards enzymatically-driven destabilization and/or functionalization, thereby allowing control of the release of encapsulated therapeutics within the diseased tissue upon intrinsic stimulation from tumor-associated enzymes...... in tumor-bearing mice.The safety and efficacy of sPLA2-sensitive liposomal L-OHP was assessed in sPLA2-deficient FaDu hypopharyngeal squamous cell carcinoma and sPLA2-expressing Colo205 colorectal adenocarcinoma. Also, the feasibility of multimodal cancer therapy employing L-OHP encapsulated in MMP...

  17. Propulsion of liposomes using bacterial motors

    International Nuclear Information System (INIS)

    Zhang Zhenhai; Li Kejie; Li Zhifei; Yu Wei; Xie Zhihong; Shi Zhiguo

    2013-01-01

    Here we describe the utilization of flagellated bacteria as actuators to propel spherical liposomes by attaching bacteria to the liposome surface. Bacteria were stably attached to liposomes using a cross-linking antibody. The effect of the number of attached bacteria on propulsion speed was experimentally determined. The effects of bacterial propulsion on the bacteria–antibody–liposome complex were stochastic. We demonstrated that liposomal mobility increased when bacteria were attached, and the propulsion speed correlated with the number of bacteria. (paper)

  18. Biological activity of liposomal vanillin.

    Science.gov (United States)

    Castan, Leniher; Del Toro, Grisel; Fernández, Adolfo A; González, Manuel; Ortíz, Emilia; Lobo, Daliana

    2013-06-01

    This article presents a study of vanillin encapsulation inside multilamellar liposomes, with emphasis on the evaluation of antioxidant activity, the hemolytic effect, and the antisickling properties of these products. Egg phosphatidylcholine-cholesterol and egg phosphatidylcholine-cholesterol-1-O-decylglycerol liposomes were prepared by mechanical dispersion, all with vanillin included. Vesicles were characterized by determination of encapsulation efficiency and vanillin retention capacity. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. The hemolytic effect of liposomes was also evaluated by spectrophotometry, as well as the antisickling activity by the Huck test using optical microscopy. Results showed that the lipid composition of liposomes did not significantly affect the encapsulation efficiency. Stable vesicles were obtained with a high retention percentage of vanillin. Liposomes exhibited a high capture of the DPPH radical compared to free vanillin and 1-O-decylglycerol (C10) in solution. Vesicles caused no significant hemolisys in normal erythrocytes, nor in those coming from patients with sickle cell anemia. Vanillin encapsulated in liposomes retained its antisickling activity, with a greater effect for C10-containing vesicles. Our results show that vanillin encapsulation in liposomes is a way to enhance the pharmacologic properties of this molecule using a suitable vehicle.

  19. Liposome Technology for Industrial Purposes

    Directory of Open Access Journals (Sweden)

    Andreas Wagner

    2011-01-01

    Full Text Available Liposomes, spherical vesicles consisting of one or more phospholipid bilayers, were first described in the mid 60s by Bangham and coworkers. Since then, liposomes have made their way to the market. Today, numerous lab scale but only a few large-scale techniques are available. However, a lot of these methods have serious limitations in terms of entrapment of sensitive molecules due to their exposure to mechanical and/or chemical stress. This paper summarizes exclusively scalable techniques and focuses on strengths, respectively, limitations in respect to industrial applicability. An additional point of view was taken to regulatory requirements concerning liposomal drug formulations based on FDA and EMEA documents.

  20. Self-association of analgesics in aqueous solution: micellar properties of dextropropoxyphene hydrochloride and methadone hydrochloride.

    Science.gov (United States)

    Attwood, D; Tolley, J A

    1980-08-01

    The solution properties of several analgesics including dextropropoxyphene hydrochloride, methadone hydrochloride, dextromoramide acid tartrate and dipipanone hydrochloride have been examined using light scattering, conductivity, vapour pressure osmometry and surface tension techniques. A micellar pattern of association was established for dextropropoxyphene hydrochloride and methadone hydrochloride and critical micelle concentrations and aggregation numbers are reported. The hydrophobic contribution to the free energy of micellization of dextropropoxyphene was determined from measurement of the critical micelle concentration in the presence of added electrolyte.

  1. Phospholipid liposomes functionalized by protein

    Science.gov (United States)

    Glukhova, O. E.; Savostyanov, G. V.; Grishina, O. A.

    2015-03-01

    Finding new ways to deliver neurotrophic drugs to the brain in newborns is one of the contemporary problems of medicine and pharmaceutical industry. Modern researches in this field indicate the promising prospects of supramolecular transport systems for targeted drug delivery to the brain which can overcome the blood-brain barrier (BBB). Thus, the solution of this problem is actual not only for medicine, but also for society as a whole because it determines the health of future generations. Phospholipid liposomes due to combination of lipo- and hydrophilic properties are considered as the main future objects in medicine for drug delivery through the BBB as well as increasing their bioavailability and toxicity. Liposomes functionalized by various proteins were used as transport systems for ease of liposomes use. Designing of modification oligosaccharide of liposomes surface is promising in the last decade because it enables the delivery of liposomes to specific receptor of human cells by selecting ligand and it is widely used in pharmacology for the treatment of several diseases. The purpose of this work is creation of a coarse-grained model of bilayer of phospholipid liposomes, functionalized by specific to the structural elements of the BBB proteins, as well as prediction of the most favorable orientation and position of the molecules in the generated complex by methods of molecular docking for the formation of the structure. Investigation of activity of the ligand molecule to protein receptor of human cells by the methods of molecular dynamics was carried out.

  2. EXPERIMENTAL LIPOSOMAL VIRAL VACCINE SAFETY

    Directory of Open Access Journals (Sweden)

    Romanova OA

    2016-12-01

    Full Text Available Introduction. With the transport links development there is rather important issue respiratory viral infections spread, especially influenza. The only method controlling influenza is vaccination. Search and development effective and safe vaccines is important. Material and methods. In base SO "Mechnikov Institute Microbiology and Immunology National Ukrainian Academy Medical Sciences" in the scientific theme "Developing new approaches to creating viral vaccines and study specific activity depending of type and degree component`s modification" was created several experimental influenza vaccine with subsequent component`s modification for selecting the most optimal pattern of safety and immunogenicity. In assessing the influenza vaccine safety is using a few criteria, including, reactivity, as measured by the frequency of local and systemic adverse (negative effects, which due to its introduction, and for lipid content drugs, ability to influence oxidation processes. At present study phase was determined: a systemic reaction and local reaction of delayed-type hypersensitivity (foot pad swelling assay;b lipids and proteins peroxidation processes after administration officinal and experimental vaccines (content protein’s carbonyl groups, lipid’s hydroperoxides, activity of glutathione-peroxidase.Study objects were trivalent seasonal influenza vaccine, "Vaxigrip" (Sanofi Pasteur, S.A., France, "Inflexal V" (Biotech Ltd. Berne, Switzerland and experimental vaccine samples. Highest immunogenicity vaccines had undergone improvements and modifications using adjuvant systems and acylation influenza proteins. Liposomes 2 – the experimental influenza vaccine with a liposome negative charge and antigenic composition like split vaccines "Vaksihryp". Liposomes 2.1 - the adjuvantexperimental influenza vaccine with modifications liposomal components (etoniy and chlorophyllipt molecules embedded in liposomal membrane. Liposomes 2.2 - the adjuvant

  3. Spectrophotometric determination of eflornithine hydrochloride ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a spectrophotometric method for the quantitative determination of eflornithine hydrochloride as a pure compound and in pharmaceutical formulations. Methods: The method involved the reaction of the target compound with vanillin reagent at specific pH 5.6 to produce a green reddish color ...

  4. Spectrophotometric Determination of Eflornithine Hydrochloride ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a spectrophotometric method for the quantitative determination of eflornithine hydrochloride as a pure compound and in pharmaceutical formulations. Methods: The method involved the reaction of the target compound with vanillin reagent at specific pH. 5.6 to produce a green reddish color ...

  5. Liposomal preparation by supercritical fluids technology | Zhong ...

    African Journals Online (AJOL)

    African Journal of Biotechnology ... technology (SCF) has been utilized in liposomal preparation because of its friendliness, nontoxicity to the environment and its possibility to achieve solvent-free liposomes and industrial-scale of liposome production under the conditions of current good manufacturing practice (cGMP).

  6. Octanol-assisted liposome assembly on chip

    NARCIS (Netherlands)

    Deshpande, S.R.; Caspi, Y.; Meijering, A.E.C.; Dekker, C.

    2016-01-01

    Liposomes are versatile supramolecular assemblies widely used in basic and applied sciences. Here we present a novel microfluidics-based method, octanol-assisted liposome assembly (OLA), to form monodisperse, cell-sized (5–20 μm), unilamellar liposomes with excellent encapsulation efficiency. Akin

  7. Two simple amine hydrochlorides from the soft coral Lobophytum strictum

    Digital Repository Service at National Institute of Oceanography (India)

    Parameswaran, P.S.; Naik; Das, B.; Kamat, S.Y.

    Two simple amine hydrochlorides, viz., 1-amino-1, 1-dimethyl-3-oxo-butane hydrochloride (1) (Diacetonamine) and 2, 2, 6, 6-tetramethylpiperidone hydrochloride (2) have been isolated from the fraction of the methanolic extract of the soft coral...

  8. Cartap hydrochloride poisoning: A clinical experience

    OpenAIRE

    Boorugu, Hari K.; Chrispal, Anugrah

    2012-01-01

    Cartap hydrochloride, a nereistoxin analog, is a commonly used low toxicity insecticide. We describe a patient who presented to the emergency department with alleged history of ingestion of Cartap hydrochloride as an act of deliberate self-harm. The patient was managed conservatively. To our knowledge this is the first case report of Cartap hydrochloride suicidal poisoning. Cartap toxicity has been considered to be minimal, but a number of animal models have shown significant neuromuscular to...

  9. 21 CFR 522.1222b - Ketamine hydrochloride with promazine hydrochloride and aminopentamide hydrogen sulfate injection.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ketamine hydrochloride with promazine... RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222b Ketamine.... Ketamine hydrochloride, (±),-2-(o-chlorophenyl)-2-(methylamino) cyclohexanone hydrochloride, with promazine...

  10. 21 CFR 522.2470 - Tiletamine hydrochloride and zolazepam hydrochloride for injection.

    Science.gov (United States)

    2010-04-01

    ... hydrochloride for injection. 522.2470 Section 522.2470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... injection. (a) Specifications. Tiletamine hydrochloride and zolazepam hydrochloride for injection when... pound of body weight. The maximum total safe dose is 13.6 milligrams per pound of body weight. (ii) In...

  11. Liposomal bupivacaine infiltration at the surgical site for the management of postoperative pain.

    Science.gov (United States)

    Hamilton, Thomas W; Athanassoglou, Vassilis; Mellon, Stephen; Strickland, Louise H; Trivella, Marialena; Murray, David; Pandit, Hemant G

    2017-02-01

    Despite multi-modal analgesic techniques, acute postoperative pain remains an unmet health need, with up to three quarters of people undergoing surgery reporting significant pain. Liposomal bupivacaine is an analgesic consisting of bupivacaine hydrochloride encapsulated within multiple, non-concentric lipid bi-layers offering a novel method of sustained-release analgesia. To assess the analgesic efficacy and adverse effects of liposomal bupivacaine infiltration at the surgical site for the management of postoperative pain. On 13 January 2016 we searched CENTRAL, MEDLINE, MEDLINE In-Process, Embase, ISI Web of Science and reference lists of retrieved articles. We obtained clinical trial reports and synopses of published and unpublished studies from Internet sources, and searched clinical trials databases for ongoing trials. Randomised, double-blind, placebo- or active-controlled clinical trials in people aged 18 years or over undergoing elective surgery, at any surgical site, were included if they compared liposomal bupivacaine infiltration at the surgical site with placebo or other type of analgesia. Two review authors independently considered trials for inclusion, assessed risk of bias, and extracted data. We performed data analysis using standard statistical techniques as described in the Cochrane Handbook for Systematic Reviews of Interventions, using Review Manager 5.3. We planned to perform a meta-analysis and produce a 'Summary of findings' table for each comparison however there were insufficient data to ensure a clinically meaningful answer. As such we have produced two 'Summary of findings' tables in a narrative format. Where possible we assessed the quality of evidence using GRADE. We identified nine studies (10 reports, 1377 participants) that met inclusion criteria. Four Phase II dose-escalating/de-escalating trials, designed to evaluate and demonstrate efficacy and safety, presented pooled data that we could not use. Of the remaining five parallel

  12. Filter-extruded liposomes revisited

    DEFF Research Database (Denmark)

    Hinna, Askell; Steiniger, Frank; Hupfeld, Stefan

    2016-01-01

    (pore-size, number of filter passages, and flow-rate), flow field-flow fractionation in conjunction with multi-angle laser light scattering (AF4-MALLS, Wyatt Technology Corp., Santa Barbara, CA) was employed. Liposome size-distributions determined by AF4-MALLS were compared with those of dynamic light...... is suggested to prepare large (300 nm) liposomes with rather narrow size distribution, based on the filter extrusion at defined flow-rates in combination with freeze-/ thaw-cycling and bench-top centrifugation....

  13. Floating Microparticulate Oral Diltiazem Hydrochloride Delivery ...

    African Journals Online (AJOL)

    Delivery System for Improved Delivery to Heart ... Conclusion: Microparticulate floating (gastroretentive) oral drug delivery system of diltiazem prepared ..... treatment of cardiac disease. ... hydrochloride-loaded mucoadhesive microspheres.

  14. Experimental design and optimization of raloxifene hydrochloride loaded nanotransfersomes for transdermal application

    Directory of Open Access Journals (Sweden)

    Mahmood S

    2014-09-01

    Full Text Available Syed Mahmood, Muhammad Taher, Uttam Kumar Mandal Department of Pharmaceutical Technology, Kulliyyah of Pharmacy, International Islamic University Malaysia (IIUM, Pahang Darul Makmur, Malaysia Abstract: Raloxifene hydrochloride, a highly effective drug for the treatment of invasive breast cancer and osteoporosis in post-menopausal women, shows poor oral bioavailability of 2%. The aim of this study was to develop, statistically optimize, and characterize raloxifene hydrochloride-loaded transfersomes for transdermal delivery, in order to overcome the poor bioavailability issue with the drug. A response surface methodology experimental design was applied for the optimization of transfersomes, using Box-Behnken experimental design. Phospholipon® 90G, sodium deoxycholate, and sonication time, each at three levels, were selected as independent variables, while entrapment efficiency, vesicle size, and transdermal flux were identified as dependent variables. The formulation was characterized by surface morphology and shape, particle size, and zeta potential. Ex vivo transdermal flux was determined using a Hanson diffusion cell assembly, with rat skin as a barrier medium. Transfersomes from the optimized formulation were found to have spherical, unilamellar structures, with a ­homogeneous distribution and low polydispersity index (0.08. They had a particle size of 134±9 nM, with an entrapment efficiency of 91.00%±4.90%, and transdermal flux of 6.5±1.1 µg/cm2/hour. Raloxifene hydrochloride-loaded transfersomes proved significantly superior in terms of amount of drug permeated and deposited in the skin, with enhancement ratios of 6.25±1.50 and 9.25±2.40, respectively, when compared with drug-loaded conventional liposomes, and an ethanolic phosphate buffer saline. Differential scanning calorimetry study revealed a greater change in skin structure, compared with a control sample, during the ex vivo drug diffusion study. Further, confocal laser

  15. Renal-targeted delivery of triptolide by entrapment in pegylated TRX-20-modified liposomes.

    Science.gov (United States)

    Yuan, Zhi-Xiang; Jia, Lu; Lim, Lee Yong; Lin, Ju-Chun; Shu, Gang; Zhao, Ling; Ye, Gang; Liang, Xiao-Xia; Ji, Hongming; Fu, Hua-Lin

    2017-01-01

    Previously, 3,5-dipentadecyloxybenzamidine hydrochloride (TRX-20)-modified liposomes were reported to specifically target mesangial cells (MCs) in glomeruli. To further gain a better understanding of the characteristics and potential application for glomerular diseases of TRX-20-modified liposomes, we synthesized TRX-20 and prepared TRX-20-modified liposomes (TRX-LPs) with different molar ratios - 6% (6%-TRX-LP), 11% (11%-TRX-LP), and 14% (14%-TRX-LP) - of TRX-20 to total lipid in the present study. All TRX-LPs exhibited concentration-dependent toxicity against the MCs at a lipid concentration ranging from 0.01 to 1.0 mg/mL with IC 50 values of 3.45, 1.13, and 0.55 mg/mL, respectively. Comparison of the cell viability of TRX-LPs indicated that high levels of TRX-20 caused severe cell mortality, with 11%-TRX-LP showing the higher cytoplasmic accumulation in the MCs. Triptolide (TP) as a model drug was first loaded into 11%-TRX-LP and the liposomes were further modified with PEG 5000 (PEG-TRX-TP-LP) in an attempt to prolong their circulation in blood and enhance TP-mediated immune suppression. Due to specific binding to MCs, PEG-TRX-TP-LP undoubtedly showed better anti-inflammatory action in vitro, evidenced by the inhibition of release of nitric oxide (NO) and tumor necrosis factor-α from lipopolysaccharide-stimulated MCs, compared with free TP at the same dose. In vivo, the PEG-TRX-TP-LP effectively attenuated the symptoms of membranous nephropathic (MN) rats and improved biochemical markers including proteinuria, serum cholesterol, and albumin. Therefore, it can be concluded that the TRX-modified liposome is an effective platform to target the delivery of TP to glomeruli for the treatment of MN.

  16. Liposomes as carriers of imaging agents

    International Nuclear Information System (INIS)

    Caride, V.J.

    1985-01-01

    This review discusses the utilization of liposomes as imaging agents or as vehicles for contrast materials. The initial approach was the use of radiolabeled liposomes for scintigraphy. To this end liposomes were either labeled in the lipid membrane or aqueous radiotracers were incorporated inside the lipid vesicles. The lipid labeling provides a more stable association of the radioactive tracer and the lipid vesicles, while the use of water-soluble radiotracers provides a wider selection of compounds. Early attempts at selective tumor imaging using radiolabeled liposomes were unsuccessful. The use of monoclonal antibodies attached to liposomes offers new hopes. Several strategies have been proposed in this respect and several others can be envisioned. The use of liposomes permits the use of several administration routes for imaging agents. Of particular interest is the subcutaneous administration for lymph node visualization. Liposomes offer clear advantages over most radiocontrast agents for prolonged hepatosplenic contrast enhancement. This is particularly relevant in the diagnostic evaluation of the abdomen with computed tomography. Important research efforts are being conducted in this area. Two different approaches have been advanced: the incorporation of contrast agents into liposomes and the preparation of radiopaque liposomes from radiodense lipids. Nuclear magnetic resonance imaging can also benefit from contrast agents. Several centers are investigating this exciting field using liposomes loaded with paramagnetic elements.152 references

  17. Dehydration of detomidine hydrochloride monohydrate.

    Science.gov (United States)

    Veldre, K; Actiņš, A; Jaunbergs, J

    2011-10-09

    The thermodynamic stability of detomidine hydrochloride monohydrate has been evaluated on the basis of phase transition kinetics in solid state. A method free of empirical models was used for the treatment of kinetic data, and compared to several known solid state kinetic data processing methods. Phase transitions were monitored by powder X-ray diffraction (PXRD) and thermal analysis. Full PXRD profiles were used for determining the phase content instead of single reflex intensity measurements, in order to minimize the influence of particle texture. We compared the applicability of isothermal and nonisothermal methods to our investigation of detomidine hydrochlorine monohydrate dehydration. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Entrapment of ovalbumin into liposomes--factors affecting entrapment efficiency, liposome size, and zeta potential.

    Science.gov (United States)

    Brgles, Marija; Jurasin, Darija; Sikirić, Maja Dutour; Frkanec, Ruza; Tomasić, Jelka

    2008-01-01

    Various amounts of Ovalbumin (OVA) were encapsulated into positively and negatively charged multilamellar liposomes, with the aim to investigate the entrapment efficiency in different buffers and to study their effects on the liposome size and zeta potential. Results showed that the entrapment efficiency of OVA in anionic liposomes was the same in 10 mM Phosphate Buffer (PB) as in Phosphate-Buffered Saline (PBS; PB + 0.15 M NaCl). Also, liposome size was approximately 1200 nm for all anionic liposomes incorporating OVA. The entrapment efficiency of OVA in cationic liposomes was highly dependent on ionic strength. The size of cationic liposomes was approximately 1200 nm in PBS, regardless of protein content, but increased with the amount of the incorporated protein in PB. Aggregation of cationic liposomes in PB was observed when the mass of the protein was 2.5 mg or greater. The zeta potential of anionic liposomes was negative and of cationic liposomes positive in the whole range of protein mass tested. These results show how different compositions of lipid and aqueous phases can be used to vary the entrapment efficiency, liposome size, and zeta potential--the factors that are of great importance for the use of liposomes as drug carriers.

  19. Thermoanalytical Investigation of Terazosin Hydrochloride

    Directory of Open Access Journals (Sweden)

    Mona Mohamed Abdel-Moety

    2013-02-01

    Full Text Available Purpose: Thermal analysis (TGA, DTG and DTA and differential scanning calorimetry (DSC have been used to study the thermal behavior of terazosin hydrochloride (TER. Methods: Thermogravimetric analysis (TGA/DTG, differential thermal analysis (DTA and differential scanning calorimetry (DSC were used to determine the thermal behavior and purity of the used drug. Thermodynamic parameters such as activation energy (E*, enthalpy (H*, entropy (S* and Gibbs free energy change of the decomposition (G* were calculated using different kinetic models. Results: The purity of the used drug was determined by differential scanning calorimetry (99.97% and specialized official method (99.85% indicating to satisfactory values of the degree of purity. Thermal analysis technique gave satisfactory results to obtain quality control parameters such as melting point (273 ºC, water content (7.49% and ash content (zero in comparison to what were obtained using official method: (272 ºC, (8.0% and (0.02% for melting point, water content and ash content, respectively. Conclusion: Thermal analysis justifies its application in quality control of pharmaceutical compounds due to its simplicity, sensitivity and low operational costs. DSC data indicated that the degree of purity of terazosin hydrochloride is similar to that found by official method.

  20. Modified Synthesis of Erlotinib Hydrochloride

    Directory of Open Access Journals (Sweden)

    Leila Barghi

    2012-06-01

    Full Text Available Purpose: An improved and economical method has been described for the synthesis of erlotinib hydrochloride, as a useful drug in treatment of non-small-cell lung cancer. Methods: Erlotinib hydrochloride was synthesized in seven steps starting from 3, 4-dihydroxy benzoic acid. In this study, we were able to modify one of the key steps which involved the reduction of the 6-nitrobenzoic acid derivative to 6-aminobenzoic acid derivative. An inexpensive reagent such as ammonium formate was used as an in situ hydrogen donor in the presence of palladium/charcoal (Pd/C instead of hydrogen gas at high pressure. Results: This proposed method proceeded with 92% yield at room temperature. Synthesis of erlotinib was completed in 7 steps with overall yield of 44%.Conclusion: From the results obtained it can be concluded that the modified method eliminated the potential danger associated with the use of hydrogen gas in the presence of flammable catalysts. It should be mentioned that the catalyst was recovered after the reaction and could be used again.

  1. Preparation and ocular pharmacokinetics of ganciclovir liposomes

    OpenAIRE

    Shen, Yan; Tu, Jiasheng

    2007-01-01

    Ophthalmic liposomes of ganciclovir (GCV) were prepared by the reverse phase evaporation method, and their ocular pharmacokinetics in albino rabbits were compared with those obtained after dosing with GCV solution. The in vitro transcorneal permeability of GCV liposomes was found to be 3.9-fold higher than that of the solution. After in vivo instillation in albino rabbits, no difference was found in the precorneal elimination rate of GCV from liposome vs solution dosing. The aqueous humor con...

  2. Evaluation of Extrusion Technique for Nanosizing Liposomes

    Directory of Open Access Journals (Sweden)

    Sandy Gim Ming Ong

    2016-12-01

    Full Text Available The aim of the present study was to study the efficiency of different techniques used for nanosizing liposomes. Further, the aim was also to evaluate the effect of process parameters of extrusion techniques used for nanosizing liposomes on the size and size distribution of the resultant liposomes. To compare the efficiency of different nanosizing techniques, the following techniques were used to nanosize the liposomes: extrusion, ultrasonication, freeze-thaw sonication (FTS, sonication and homogenization. The extrusion technique was found to be the most efficient, followed by FTS, ultrasonication, sonication and homogenization. The extruder used in the present study was fabricated using readily available and relatively inexpensive apparatus. Process parameters were varied in extrusion technique to study their effect on the size and size distribution of extruded liposomes. The results obtained indicated that increase in the flow rate of the extrusion process decreased the size of extruded liposomes however the size homogeneity was negatively impacted. Furthermore, the liposome size and distribution was found to decline with decreasing membrane pore size. It was found that by extruding through a filter with a pore size of 0.2 µm and above, the liposomes produced were smaller than the pore size, whereas, when they were extruded through a filter with a pore size of less than 0.2 µm the resultant liposomes were slightly bigger than the nominal pore size. Besides that, increment of extrusion temperature above transition temperature of the pro-liposome had no effect on the size and size distribution of the extruded liposomes. In conclusion, the extrusion technique was reproducible and effective among all the methods evaluated. Furthermore, processing parameters used in extrusion technique would affect the size and size distribution of liposomes. Therefore, the process parameters need to be optimized to obtain a desirable size range and homogeneity

  3. The Role of Cavitation in Liposome Formation

    OpenAIRE

    Richardson, Eric S.; Pitt, William G.; Woodbury, Dixon J.

    2007-01-01

    Liposome size is a vital parameter of many quantitative biophysical studies. Sonication, or exposure to ultrasound, is used widely to manufacture artificial liposomes, yet little is known about the mechanism by which liposomes are affected by ultrasound. Cavitation, or the oscillation of small gas bubbles in a pressure-varying field, has been shown to be responsible for many biophysical effects of ultrasound on cells. In this study, we correlate the presence and type of cavitation with a decr...

  4. Liposomes - experiment of magnetic resonance imaging application

    International Nuclear Information System (INIS)

    Mathieu, S.

    1987-01-01

    Most pharmaceutical research effort with liposomes has been involved with the investigation of their use as drug carriers to particular target organs. Recently there has been a growing interest in liposomes not only as carrier of drugs but as a tool for the introduction of various substances into the human body. In this study, liposome delivery of nitroxyl radicals as NMR contrast agent for improved tissue imaging is experimented in rats [fr

  5. Liposome kinetics in infarcted canine myocardium

    International Nuclear Information System (INIS)

    Caride, V.J.; Twickler, J.; Zaret, B.L.

    1984-01-01

    To study the mechanisms and kinetics of liposome deposition in the region of the experimental myocardial infarction, the myocardial distribution of positive and negative liposomes was determined as a function of regional myocardial blood flow and time after administration. The study was performed in dogs at 1 and 24 h following experimental myocardial infarction. Twenty-four hours after coronary artery occlusion, the initial myocardial distribution of positive and negative liposomes (2 min) is directly proportional to regional myocardial blood flow. With time, there is reduction of the radiotracer associated with negative liposomes from all myocardial regions (p less than 0.01). In contrast, in areas of moderate and severe blood flow reduction, there is progressive accumulation of tracers entrapped or incorporated in positive liposomes. This increment becomes significant in 120 min (p less than 0.005). Similar findings are observed in studies performed 1 h after coronary artery occlusion. Dual-label liposomes [( 3 H]cholesterol and [99mTc]diethylenetriamine pentaacetic acid) were used to study the integrity of liposomes in normal and ischemic myocardium. Significant dissociation of the aqueous and lipid labels of positive liposomes is observed 1 h following coronary artery occlusion. In the 24-h myocardial infarction model, dissociation of the aqueous and lipid labels in ischemic myocardium is also observed. This phenomenon is more pronounced with positive than with negative liposomes (p less than 0.02)

  6. Photosensitization of liposomes by porphyrins

    Energy Technology Data Exchange (ETDEWEB)

    Grossweiner, L I; Goyal, G C

    1984-01-01

    Lipid peroxidation was photosensitized in egg phosphatidylcholine (EPC) liposomes by hematoporphyrin (HP), hematoporphyrin derivative (HpD) and uroporphyrin I (Uro-I). Photosensitization by HP was type II via singlet oxygen (/sup 1/O/sub 2/) for the monomeric and dimeric states and type I for aggregated HP. Uro-I was an efficient type II /sup 1/O/sub 2/ photosensitizer. The HpD fraction enriched in the active biological component (HpD-A) was a type II /sup 1/O/sub 2/ photosensitizer at high and low concentrations. The spectral differences between HpD-A in buffer and solubilized in small EPC liposomes are attributed to a conformation change of a key dimer constituent from a folded to a planar geometry. The implications of the results for the action mechanism in photoradiation therapy of tumors with these porphyrins are discussed. 73 references, 1 figure, 5 tables.

  7. DNA controlled assembly of liposomes

    DEFF Research Database (Denmark)

    Vogel, Stefan; Jakobsen, Ulla; Simonsen, Adam Cohen

    2009-01-01

    DNA-encoding of solid nanoparticles requires surfacechemistry, which is often tedious and not generally applicable. In the present study non-covalently attached DNA are used to assemble soft nanoparticles (liposomes) in solution. This process displays remarkably sharp thermal transitions from...... assembled to disassembled state for which reason this method allows easy and fast detection of polynucleotides (e.g. DNA or RNA), including single nucleotide polymorphisms as well as insertions and deletions....

  8. Laccases stabilization with phosphatidylcholine liposomes

    OpenAIRE

    Martí, M.; Zille, Andrea; Paulo, Artur Cavaco; Parra, J. L.; Coderch, L.

    2012-01-01

    In recent years, there has been an upsurge of interest in enzyme treatment of textile fibres. Enzymes are globular proteins whose catalytic function is due to their three dimensional structure. For this reason, stability strategies make use of compounds that avoid dismantling or distorting protein 3D structures. This study is concerned with the use of microencapsulation techniques to optimize enzyme stabilization. Laccases were embedded in phophatidylcholine liposomes and their encaps...

  9. Liposomal Bupivacaine for Pain Control After Anterior Cruciate Ligament Reconstruction: A Prospective, Double-Blinded, Randomized, Positive-Controlled Trial.

    Science.gov (United States)

    Premkumar, Ajay; Samady, Heather; Slone, Harris; Hash, Regina; Karas, Spero; Xerogeanes, John

    2016-07-01

    Local anesthetics are commonly administered into surgical sites as a part of multimodal pain control regimens. Liposomal bupivacaine is a novel formulation of bupivacaine designed for slow diffusion of a single dose of local anesthetic over a 72-hour period. While early results are promising in various settings, no studies have compared pain management regimens containing liposomal bupivacaine to traditional regimens in patients undergoing anterior cruciate ligament (ACL) reconstruction. To evaluate liposomal bupivacaine in comparison with 0.25% bupivacaine hydrochloride (HCl) for pain control after ACL reconstruction. Randomized controlled trial; Level of evidence, 1. A total of 32 adult patients undergoing primary ACL reconstruction with a soft tissue quadriceps tendon autograft between July 2014 and March 2015 were enrolled. All patients received a femoral nerve block immediately before surgery. Patients then received either a 40-mL suspension of 20 mL Exparel (1 vial of bupivacaine liposome injectable suspension) and 20 mL 0.9% injectable saline or 20 mL 0.5% bupivacaine HCl and 20 mL 0.9% injectable saline, which was administered into the graft harvest site and portal sites during surgery. Patients were given either a postoperative smartphone application or paper-based journal to record data for 1 week after ACL reconstruction. Of the 32 patients recruited, 29 patients were analyzed (90.6%). Two patients were lost to follow-up, and 1 was excluded because of a postoperative hematoma. There were no statistically significant differences in postoperative pain, medication use, pain location, recovery room time, or mobility between the 2 study groups. There were comparable outcomes with 0.25% bupivacaine HCl at a 200-fold lower cost than liposomal bupivacaine. This study does not support the widespread use of liposomal bupivacaine for pain control after ACL reconstruction in the setting of a femoral nerve block. ClinicalTrials.gov NCT02189317. © 2016 The Author(s).

  10. Application of statistical experimental design to study the formulation variables influencing the coating process of lidocaine liposomes.

    Science.gov (United States)

    González-Rodríguez, M L; Barros, L B; Palma, J; González-Rodríguez, P L; Rabasco, A M

    2007-06-07

    In this paper, we have used statistical experimental design to investigate the effect of several factors in coating process of lidocaine hydrochloride (LID) liposomes by a biodegradable polymer (chitosan, CH). These variables were the concentration of CH coating solution, the dripping rate of this solution on the liposome colloidal dispersion, the stirring rate, the time since the liposome production to the liposome coating and finally the amount of drug entrapped into liposomes. The selected response variables were drug encapsulation efficiency (EE, %), coating efficiency (CE, %) and zeta potential. Liposomes were obtained by thin-layer evaporation method. They were subsequently coated with CH according the experimental plan provided by a fractional factorial (2(5-1)) screening matrix. We have used spectroscopic methods to determine the zeta potential values. The EE (%) assay was carried out in dialysis bags and the brilliant red probe was used to determine CE (%) due to its property of forming molecular complexes with CH. The graphic analysis of the effects allowed the identification of the main formulation and technological factors by the analysis of the selected responses and permitted the determination of the proper level of these factors for the response improvement. Moreover, fractional design allowed quantifying the interactions between the factors, which will consider in next experiments. The results obtained pointed out that LID amount was the predominant factor that increased the drug entrapment capacity (EE). The CE (%) response was mainly affected by the concentration of the CH solution and the stirring rate, although all the interactions between the main factors have statistical significance.

  11. Acute Psychotic Symptoms due to Benzydamine Hydrochloride Abuse with Alcohol

    Directory of Open Access Journals (Sweden)

    Yahya Ayhan Acar

    2014-01-01

    Full Text Available Benzydamine hydrochloride is a locally acting nonsteroidal anti-inflammatory drug. Benzydamine hydrochloride overdose can cause stimulation of central nervous system, hallucinations, and psychosis. We presented a young man with psychotic symptoms due to benzydamine hydrochloride abuse. He received a total dose of 1000 mg benzydamine hydrochloride with alcohol for its hallucinative effects. Misuse of benzydamine hydrochloride must be considered in differential diagnosis of first-episode psychosis and physicians should consider possibility of abuse in prescribing.

  12. Immobilization of swift foxes with ketamine hydrochloride-xylazine hydrochloride

    Science.gov (United States)

    Telesco, R.L.; Sovada, Marsha A.

    2002-01-01

    There is an increasing need to develop field immobilization techniques that allow researchers to handle safely swift foxes (Vulpes velox) with minimal risk of stress or injury. We immobilized captive swift foxes to determine the safety and effectiveness of ketamine hydrochloride and xylazine hydrochloride at different dosages. We attempted to determine appropriate dosages to immobilize swift foxes for an adequate field-handling period based on three anesthesia intervals (induction period, immobilization period, and recovery period) and physiologic responses (rectal temperature, respiration rate, and heart rate). Between October 1998–July 1999, we conducted four trials, evaluating three different dosage ratios of ketamine and xylazine (2.27:1.2, 5.68:1.2, and 11.4:1.2 mg/kg ketamine:mg/kg xylazine, respectively), followed by a fourth trial with a higher dosage at the median ratio (11.4 mg/kg ketamine:2.4 mg/kg xylazine). We found little difference in induction and recovery periods among trials 1–3, but immobilization time increased with increasing dosage (Pimmobilization period and recovery period increased in trial 4 compared with trials 1–3 (P≤0.03). There was a high variation in responses of individual foxes across trials, making it difficult to identify an appropriate dosage for field handling. Heart rate and respiration rates were depressed but all physiologic measures remained within normal parameters established for domestic canids. We recommend a dosage ratio of 10 mg/kg ketamine to 1 mg/kg xylazine to immobilize swift foxes for field handling.

  13. Nanoparticle Stabilized Liposomes for Acne Therapy

    Science.gov (United States)

    Fu, Victoria

    Acne vulgaris is a common skin disease that affects over 40 million people in the United States alone. The main cause of acne vulgaris is Propionibacterium acnes (P. acnes), resides deep in the pores and follicles of the skin in order to feed on oil produced by the sebaceous glands. The liposome is a lipid based nanoparticle with numerous advantages over free drug molecules as an acne treatment alternative. Bare liposomes loaded with lauric acid (LipoLA) were found to show strong antimicrobial activity against P. acnes while generating minimal toxicity. However, the platform is limited by the spontaneous tendency of liposomes to fuse with each other. Attaching nanoparticles to the surface of liposomes can overcome this challenge by providing steric repulsion and reduce surface tension. Thus, carboxyl-functionalized gold nanoparticles (AuC) were attached to the surface of liposomes (AuC-liposomes) loaded with doxycycline, a general tetracycline antibiotic. These particles were found to have a diameter of 120 nm and a zeta potential of 20.0 mV. Both fluorescent and antimicrobial studies demonstrated that based on electrostatic interaction, negatively charged AuC attached to the liposome's positively charged surface and stabilized liposomes in a neutral pH environment (pH = 7.4). Upon entering the skin's acidic environment (pH = 4), AuC detached from the liposome's surface and liposomes could fuse with P. acnes residing in the pores. Furthermore, toxicity studies showed that AuC-liposomes did not induce any significant toxicity, while two of the leading over-the-counter therapies, benzoyl peroxide and salicylic acid, generated substantial skin irritation.

  14. Stability Indicating HPLC Method for Simultaneous Quantification of Trihexyphenidyl Hydrochloride, Trifluoperazine Hydrochloride and Chlorpromazine Hydrochloride from Tablet Formulation

    Directory of Open Access Journals (Sweden)

    P. Shetti

    2010-01-01

    Full Text Available A new, simple, precise, rapid, selective and stability indicating reversed-phase high performance liquid chromatographic (HPLC method has been developed and validated for simultaneous quantification of trihexyphenidyl hydrochloride, trifluoperazine hydrochloride and chlorpromazine hydrochloride from combined tablet formulation. The method is based on reverse-phase using C-18 (250×4.6 mm, 5 μm particle size column. The separation is achieved using isocratic elution by methanol and ammonium acetate buffer (1% w/v, pH 6.5 in the ratio of 85:15 v/v, pumped at flow rate 1.0 mL/min and UV detection at 215 nm. The column is maintained at 30 °C through out the analysis. This method gives baseline resolution. The total run time is 15 min. Stability indicating capability is established buy forced degradation experiment. The method is validated for specificity, accuracy, precision and linearity as per International conference of harmonisation (ICH. The method is accurate and linear for quantification of trihexyphenidyl hydrochloride, trifluoperazine hydrochloride and Chlorpromazine hydrochloride between 5 - 15 μg/mL, 12.5- 37.5 μg/mL and 62.5 - 187.5 μg/mL respectively.

  15. 141 137 Effect of Guanidium Hydrochloride o

    African Journals Online (AJOL)

    2008-12-02

    Dec 2, 2008 ... Effect of Guanidium Hydrochloride on the Stability of Horse Skeletal. Muscle Myoglobin ... Proteins carry out the most important tasks in living organisms. To do so, most proteins fold spontaneously into a well defined three –.

  16. Cinacalcet hydrochloride for the treatment of hyperparathyroidism

    NARCIS (Netherlands)

    Verheyen, N.; Pilz, S.; Eller, K.; Kienreich, K.; Fahrleitner-Pammer, A.; Pieske, B.; Ritz, E.; Tomaschitz, A.

    2013-01-01

    Introduction: Effective therapeutic strategies are warranted to reduce the burden of parathyroid hormone excess related morbidity and mortality. The calcimimetic agent cinacalcet hydrochloride is a promising treatment strategy in hyperparathyroidism. Areas covered: This review provides an overview

  17. Methods for using redox liposome biosensors

    Science.gov (United States)

    Cheng, Quan; Stevens, Raymond C.

    2002-01-01

    The present invention provides methods and compositions for detecting the presence of biologically-important analytes by using redox liposome biosensors. In particular, the present invention provides liposome/sol-gel electrodes suitable for the detection of a wide variety of organic molecules, including but not limited to bacterial toxins.

  18. Astragaloside IV liposomes ameliorates adriamycin-induced ...

    African Journals Online (AJOL)

    Methods: The rats were given a single tail intravenous injection of adriamycin (6 mg/kg) within 1 week, and then divided into four groups including normal, model, benazepril and astragaloside IV liposomes group. They were all orally administered dosage of benazepril and astragaloside IV liposomes once daily for 8 weeks.

  19. Preparation and ocular pharmacokinetics of ganciclovir liposomes.

    Science.gov (United States)

    Shen, Yan; Tu, Jiasheng

    2007-12-07

    Ophthalmic liposomes of ganciclovir (GCV) were prepared by the reverse phase evaporation method, and their ocular pharmacokinetics in albino rabbits were compared with those obtained after dosing with GCV solution. The in vitro transcorneal permeability of GCV liposomes was found to be 3.9-fold higher than that of the solution. After in vivo instillation in albino rabbits, no difference was found in the precorneal elimination rate of GCV from liposome vs solution dosing. The aqueous humor concentration-time profiles of both liposomes and solution were well described by 2-compartmental pharmacokinetics with first-order absorption. The area under the curve of the aqueous humor concentration-time profiles of GCV liposomes was found to be 1.7-fold higher than that of GCV solution. Ocular tissue distribution of GCV from liposomes was 2 to 10 times higher in the sclera, cornea, iris, lens, and vitreous humor when compared with those observed after solution dosing. These results suggested that liposomes may hold some promise in ocular GCV delivery.

  20. Stabilization of liophilized liposomal products

    Directory of Open Access Journals (Sweden)

    2001-08-01

    Full Text Available Liposomes as a drug carrier have numerous dominancy. Liophilization is the most propr form of these products for long-term maintenance, but this procedure is affected by unstabilizing agent that results in destruction of membrane, release of content and change in size and microbial contamination; hence for prevention of the adverse effects, the protective role of sugars such as: Maltose, Fructose, Glucose, Galactose, Saccharose and Lactose were studied. For this purpose, after preparation of liposomal suspention, categorized in for duplicate groups and concentrations of 25, 50, 100 percent of these sugars were added to those. On the basis of color and consistency of products, the best method of freezing is as application of absolute alcohol and then chilling in-70 oc for 16 h. In survey of protective substances concentrations 0.7, 1.4, 2.8, and 5.6 percent of the mentioned sugars were used for calculating of leakage percent (Upon on the ratio of optical density of treated samples to untreated. In this study, released maltose had highest effect. Level of fusion and aggregation had any significant difference between pre and post lyophilized samples in centrifugation with 10000 rpm. Microbial state of recent samples were studied by culturing in SCD and SCDA media that indicated microbial growth in both samples.     

  1. The role of cavitation in liposome formation.

    Science.gov (United States)

    Richardson, Eric S; Pitt, William G; Woodbury, Dixon J

    2007-12-15

    Liposome size is a vital parameter of many quantitative biophysical studies. Sonication, or exposure to ultrasound, is used widely to manufacture artificial liposomes, yet little is known about the mechanism by which liposomes are affected by ultrasound. Cavitation, or the oscillation of small gas bubbles in a pressure-varying field, has been shown to be responsible for many biophysical effects of ultrasound on cells. In this study, we correlate the presence and type of cavitation with a decrease in liposome size. Aqueous lipid suspensions surrounding a hydrophone were exposed to various intensities of ultrasound and hydrostatic pressures before measuring their size distribution with dynamic light scattering. As expected, increasing ultrasound intensity at atmospheric pressure decreased the average liposome diameter. The presence of collapse cavitation was manifested in the acoustic spectrum at high ultrasonic intensities. Increasing hydrostatic pressure was shown to inhibit the presence of collapse cavitation. Collapse cavitation, however, did not correlate with decreases in liposome size, as changes in size still occurred when collapse cavitation was inhibited either by lowering ultrasound intensity or by increasing static pressure. We propose a mechanism whereby stable cavitation, another type of cavitation present in sound fields, causes fluid shearing of liposomes and reduction of liposome size. A mathematical model was developed based on the Rayleigh-Plesset equation of bubble dynamics and principles of acoustic microstreaming to estimate the shear field magnitude around an oscillating bubble. This model predicts the ultrasound intensities and pressures needed to create shear fields sufficient to cause liposome size change, and correlates well with our experimental data.

  2. Liposome fusion and lipid exchange on ultraviolet irradiation of liposomes containing a photochromic phospholipid

    International Nuclear Information System (INIS)

    Morgan, C.G.; Sandhu, S.S.; Mitchell, A.C.

    1995-01-01

    A photochromic phospholipid, 1,2-bis[4-n-butylphenylazo)phenylbutyroyl]phosphatidylcholine (Bis-Azo PC) has been incorporated inot liposomes of gel- and liquid-crystalline-phase phospholipids. Liposomes of gel-phase phospholipid are stable in the presence of the trans photostationary state Bis-Az0 PC and can encapsulate fluorescent marker dye. On photoisomerization to the cis photostationary state, trapped marker is rapidly released. Liposomes containing Bis-Azo PC can rapidly fuse together after UV isomerization, this process continuing in the dark. Exposure to white light causes reversion of Bis-Azo PC to the trans form and halts dye leakage and vesicle fusion. Both unilamellar and multilamellar liposomes are able to fuse together on UV exposure. On UV photolysis, liposomes containing Bis-Azo PC do not fuse with a large excess of unlabeled liposomes, but transfer of Bis-Azo PC can be demonstrated spectrophotometrically. Vesicles of pure gel-phase lipid containing trapped marker dye but initially no Bis-Azo PC become leaky as a result of this lipid transfer. Liposomes composed of liquid-crystalline-phase phosphatidylcholine-containing Bis-Azo PC neither leak trapped marker nor fuse together on photolysis, nor do liquid-crystalline-phase liposomes, fuse with gel-phase liposomes under these conditions. (Author)

  3. Compound list: fluoxetine hydrochloride [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available fluoxetine hydrochloride FLX 00158 ftp://ftp.biosciencedbc.jp/archive/open-tggates/...LATEST/Human/in_vitro/fluoxetine_hydrochloride.Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/o...pen-tggates/LATEST/Rat/in_vivo/Liver/Single/fluoxetine_hydrochloride.Rat.in_vivo.Liver.Single.zip ftp://ftp....biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/fluoxetine_hydrochloride.Rat.in_vivo.Liver.Repeat.zip ...

  4. Targeted drug delivery using temperature-sensitive liposomes

    International Nuclear Information System (INIS)

    Magin, R.L.; Niesman, M.R.

    1984-01-01

    Liposomes are receiving considerable attention as vehicles for selective drug delivery. One method of targeting liposomal contents involves the combination of local hyperthermia with temperature-sensitive liposomes. Such liposomes have been used to increase the uptake of methotrexate and cis-platinum into locally heated mouse tumors. However, additional information is needed on the mechanism of liposome drug release and the physiologic deposition of liposomes in vivo before clinical trails are begun. Current research is directed at studying the encapsulation and release of water soluble drugs from temperature-sensitive liposomes. The influence of liposome size, structure, and composition on the rapid release in plasma of cytosine arabinoside, cis-platinum, and the radiation sensitizer SR-2508 are described. These results demonstrate potential applications for temperature-sensitive liposomes in selective drug delivery

  5. 21 CFR 182.1047 - Glutamic acid hydrochloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Glutamic acid hydrochloride. 182.1047 Section 182.1047 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1047 Glutamic acid hydrochloride. (a) Product. Glutamic acid hydrochloride. (b...

  6. 21 CFR 522.1662a - Oxytetracycline hydrochloride injection.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride injection. 522.1662a... § 522.1662a Oxytetracycline hydrochloride injection. (a)(1) Specifications. The drug contains 50 milligrams of oxytetracycline hydrochloride in each milliliter of sterile solution. (2) Sponsor. See No...

  7. 21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride capsules. 520.1660b... Oxytetracycline hydrochloride capsules. (a) Specifications. The drug is in capsule form with each capsule containing 125 or 250 milligrams of oxytetracycline hydrochloride. Oxytetracycline is the antibiotic...

  8. 21 CFR 522.1642 - Oxymorphone hydrochloride injection.

    Science.gov (United States)

    2010-04-01

    ... § 522.1642 Oxymorphone hydrochloride injection. (a) Specifications. The drug contains 1 or 1.5 milligrams of oxymorphone hydrochloride per milliliter of aqueous solution containing 0.8 percent sodium... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxymorphone hydrochloride injection. 522.1642...

  9. 21 CFR 522.536 - Detomidine hydrochloride injection.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Detomidine hydrochloride injection. 522.536... § 522.536 Detomidine hydrochloride injection. (a) Specification. Each milliliter of sterile aqueous solution contains 10 milligrams of detomidine hydrochloride. (b) Sponsor. See 052483 in § 510.600(c) of...

  10. Liposomal curcumin and its application in cancer.

    Science.gov (United States)

    Feng, Ting; Wei, Yumeng; Lee, Robert J; Zhao, Ling

    2017-01-01

    Curcumin (CUR) is a yellow polyphenolic compound derived from the plant turmeric. It is widely used to treat many types of diseases, including cancers such as those of lung, cervices, prostate, breast, bone and liver. However, its effectiveness has been limited due to poor aqueous solubility, low bioavailability and rapid metabolism and systemic elimination. To solve these problems, researchers have tried to explore novel drug delivery systems such as liposomes, solid dispersion, microemulsion, micelles, nanogels and dendrimers. Among these, liposomes have been the most extensively studied. Liposomal CUR formulation has greater growth inhibitory and pro-apoptotic effects on cancer cells. This review mainly focuses on the preparation of liposomes containing CUR and its use in cancer therapy.

  11. Radioprotective effectiveness of Adeturone incapsulated in liposomes

    International Nuclear Information System (INIS)

    Pantev, T.

    1989-01-01

    The radioprotective properties of the radioprotector Adeturone incapsulated in mono- and tricomponent liposomes were studied. Intraperitoneal administration of the radioprotector by means of monocomponent liposomes from egg lecithin, as well as its applicaton alone immediately (15-30 min) before irradiation of mice with 7,5 Gy gamma-quanta (LD 100/30 ) guaranteed high survival -80% and 75% accordingly. Orally introduced Adeturone, incapsulated in tricomponent liposomes (dipalmitoil lecithin, cholesterol, stearinamine - 7:2:1), protected for 0,5 to 4,5 hours lethally X-irradiated mice (7,8 Gy; LD 90/30 ). Under these conditions, Adeturone applied alone 4,5 hours before irradiation was ineffective. These results show the presence of prolonged radioprotective effect of Adeturone, when orally applied in the form of liposomal suspension. 2 tabs., 17 refs

  12. Progress involving new techniques for liposome preparation

    Directory of Open Access Journals (Sweden)

    Zhenjun Huang

    2014-08-01

    Full Text Available The article presents a review of new techniques being used for the preparation of liposomes. A total of 28 publications were examined. In addition to the theories, characteristics and problems associated with traditional methods, the advantages and drawbacks of the latest techniques were reviewed. In the light of developments in many relevant areas, a variety of new techniques are being used for liposome preparation and each of these new technique has particular advantages over conventional preparation methods. However, there are still some problems associated with these new techniques that could hinder their applications and further improvements are needed. Generally speaking, due to the introduction of these latest techniques, liposome preparation is now an improved procedure. These applications promote not only advances in liposome research but also the methods for their production on an industrial scale.

  13. Plasmon resonant liposomes for controlled drug delivery

    Science.gov (United States)

    Knights-Mitchell, Shellie S.; Romanowski, Marek

    2015-03-01

    Nanotechnology use in drug delivery promotes a reduction in systemic toxicity, improved pharmacokinetics, and better drug bioavailability. Liposomes continue to be extensively researched as drug delivery systems (DDS) with formulations such as Doxil® and Ambisome® approved by FDA and successfully marketed in the United States. However, the limited ability to precisely control release of active ingredients from these vesicles continues to challenge the broad implementation of this technology. Moreover, the full potential of the carrier to sequester drugs until it can reach its intended target has yet to be realized. Here, we describe a liposomal DDS that releases therapeutic doses of an anticancer drug in response to external stimulus. Earlier, we introduced degradable plasmon resonant liposomes. These constructs, obtained by reducing gold on the liposome surface, facilitate spatial and temporal release of drugs upon laser light illumination that ultimately induces an increase in temperature. In this work, plasmon resonant liposomes have been developed to stably encapsulate and retain doxorubicin at physiological conditions represented by isotonic saline at 37o C and pH 7.4. Subsequently, they are stimulated to release contents either by a 5o C increase in temperature or by laser illumination (760 nm and 88 mW/cm2 power density). Successful development of degradable plasmon resonant liposomes responsive to near-infrared light or moderate hyperthermia can provide a new delivery method for multiple lipophilic and hydrophilic drugs with pharmacokinetic profiles that limit clinical utility.

  14. Octanol-assisted liposome assembly on chip

    Science.gov (United States)

    Deshpande, Siddharth; Caspi, Yaron; Meijering, Anna E. C.; Dekker, Cees

    2016-01-01

    Liposomes are versatile supramolecular assemblies widely used in basic and applied sciences. Here we present a novel microfluidics-based method, octanol-assisted liposome assembly (OLA), to form monodisperse, cell-sized (5-20 μm), unilamellar liposomes with excellent encapsulation efficiency. Akin to bubble blowing, an inner aqueous phase and a surrounding lipid-carrying 1-octanol phase is pinched off by outer fluid streams. Such hydrodynamic flow focusing results in double-emulsion droplets that spontaneously develop a side-connected 1-octanol pocket. Owing to interfacial energy minimization, the pocket splits off to yield fully assembled solvent-free liposomes within minutes. This solves the long-standing fundamental problem of prolonged presence of residual oil in the liposome bilayer. We demonstrate the unilamellarity of liposomes with functional α-haemolysin protein pores in the membrane and validate the biocompatibility by inner leaflet localization of bacterial divisome proteins (FtsZ and ZipA). OLA offers a versatile platform for future analytical tools, delivery systems, nanoreactors and synthetic cells.

  15. Engineering liposomal nanoparticles for targeted gene therapy.

    Science.gov (United States)

    Zylberberg, C; Gaskill, K; Pasley, S; Matosevic, S

    2017-08-01

    Recent mechanistic studies have attempted to deepen our understanding of the process by which liposome-mediated delivery of genetic material occurs. Understanding the interactions between lipid nanoparticles and cells is still largely elusive. Liposome-mediated delivery of genetic material faces systemic obstacles alongside entry into the cell, endosomal escape, lysosomal degradation and nuclear uptake. Rational design approaches for targeted delivery have been developed to reduce off-target effects and enhance transfection. These strategies, which have included the modification of lipid nanoparticles with target-specific ligands to enhance intracellular uptake, have shown significant promise at the proof-of-concept stage. Control of physical and chemical specifications of liposome composition, which includes lipid-to-DNA charge, size, presence of ester bonds, chain length and nature of ligand complexation, is integral to the performance of targeted liposomes as genetic delivery agents. Clinical advances are expected to rely on such systems in the therapeutic application of liposome nanoparticle-based gene therapy. Here, we discuss the latest breakthroughs in the development of targeted liposome-based agents for the delivery of genetic material, paying particular attention to new ligand and cationic lipid design as well as recent in vivo advances.

  16. Preparation and evaluation of doxycycline hydrochloride and bromhexine hydrochloride dosage forms for pigeons / Marga le Roux

    OpenAIRE

    Le Roux, Marga

    2004-01-01

    Objective: To prepare and evaluate three different dosage forms, containing doxycycline hydrochloride (HCI) and bromhexine hydrochloride (HCI) respectively and in combination, for the treatment of respiratory diseases in pigeons. Background: Birds have held a place in man's affection since the ancient Egyptians and Romans kept birds. Europeans have successfully bred birds, especially smaller birds and pigeons, for centuries. Only in recent years, however, have science and me...

  17. Pegylated liposomal doxorubicin in malignant pleural mesothelioma: a possible guardian for long-term survival

    Directory of Open Access Journals (Sweden)

    Zarogoulidis P

    2012-09-01

    Full Text Available Paul Zarogoulidis,1,2 Maria Mavroudi,1 Konstantinos Porpodis,1 Kalliopi Domvri,1 Antonios Sakkas,3 Nikolaos Machairiotis,1 Aikaterini Stylianaki,1 Anastasios Tsiotsios,1 Nikolaos Courcoutsakis,4 Konstantinos Zarogoulidis11Pulmonary Department-Oncology Unit, “G Papanikolaou” General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece; 2Pulmonary Department-Interventional Unit, Ruhrland Klinik, University of Essen, Essen, Germany; 3Department of Pathology, “G Papanikolaou” General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece; 4Department of Radiology, University General Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, GreeceAbstract: Malignant pleural mesothelioma is a rare and aggressive malignancy of the pleura correlated with exposure to asbestos, with a medium survival of 11–12 months after diagnosis. A case of a 67-year-old male who had previously worked in the asbestos industry and is a current smoker is reported. The computed tomography evaluation revealed a right pleural mass with pleural thickening, and the pleural biopsy confirmed a diagnosis of malignant pleural mesothelioma. He was treated with chemotherapy consisting of etoposide, paclitaxel, and pegylated liposomal doxorubicin hydrochloride. After completion of chemotherapy, radiologic evaluation confirmed a reduction of pleural thickening and improvement in his symptoms. A complete presentation of each drug formulation and characteristics are also included in this paper. The patient’s follow-up is continuing, and computed tomography reveals stable disease 9 years after initial examination.Keywords: mesothelioma, asbestos, pegylated liposomal doxorubicin

  18. Preparation and evaluation of mebeverine hydrochloride as ...

    African Journals Online (AJOL)

    Purpose: To formulate and evaluate an antispasmodic drug, mebeverine hydrochloride (Mbv-HCl), as a local anesthetic mucoadhesive buccal tablet. Methods: Mbv-HCl loaded tablets were formulated, using a direct compression technique, with varying polymer concentrations including carbopol 934P alone, carbopol ...

  19. Fe (III) complex of mefloquine hydrochloride: Synthesis ...

    African Journals Online (AJOL)

    As part of the ongoing research for more effective antimalarial drug, Fe (III) complex of mefloquine hydrochloride (antimalarial drug) was synthesized using template method. Mefloquine was tentatively found to have coordinated through the hydroxyl and the two nitrogen atoms in the quinoline and piperidine in the structure, ...

  20. Quantitative Determination of Metformin Hydrochloride in Tablet ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a suitable method for the assay of metformin hydrochloride (HCl) in tablets containing croscarmellose sodium as an additive. Methods: Methanol and ethanol (99%) were assessed as solvents for sample preparation for the assay of metformin HCl in tablets containing croscarmellose ...

  1. Cartap hydrochloride poisoning: A clinical experience.

    Science.gov (United States)

    Boorugu, Hari K; Chrispal, Anugrah

    2012-01-01

    Cartap hydrochloride, a nereistoxin analog, is a commonly used low toxicity insecticide. We describe a patient who presented to the emergency department with alleged history of ingestion of Cartap hydrochloride as an act of deliberate self-harm. The patient was managed conservatively. To our knowledge this is the first case report of Cartap hydrochloride suicidal poisoning. Cartap toxicity has been considered to be minimal, but a number of animal models have shown significant neuromuscular toxicity resulting in respiratory failure. It is hypothesized that the primary effect of Cartap hydrochloride is through inhibition of the [(3)H]-ryanodine binding to the Ca(2+) release channel in the sarcoplasmic reticulum in a dose-dependent manner and promotion of extracellular Ca(2+) influx and induction of internal Ca(2+) release. This results in tonic diaphragmatic contraction rather than paralysis. This is the basis of the clinical presentation of acute Cartap poisoning as well as the treatment with chelators namely British Anti Lewisite and sodium dimercaptopropane sulfonate.

  2. ANTISTAPHYLOCOCCAL ACTIVITY OF LIPOSOMAL FORMS OF LINCOMYCIN

    Directory of Open Access Journals (Sweden)

    Derkach SA

    2015-04-01

    Full Text Available Nowadays the vital problem of modern medicine is a tendency to emerging of both nosocomial and community-acquired strains before antibiotic resistance forming. The complexity of antibiotic therapy of diseases caused by methicillin resistant staphylococci having high poly resistance almost to every classes of antibacterial agents is of prime importance. One of the ways to improve antibacterial preparations still remains the development of their liposomal forms. This work studies antistaphylococcal activity (according to MIC of the liposomal form of lincomycin developed in the Institute of Dermatology and Venereology of Ukraine by Ivanova N. N., the Candidate of Сhemical Sciences.The purpose of this research work was to study liposomal inhibiting concentration of the liposomalny form of lincomycin and a commercial preparation lincomycin (produced by CJSC “Pharmaceutical firm "Darnitsa". Determination of the minimum inhibiting concentration was carried out by a tablet micromethod by consecutive cultivations of the samples under study.It is shown that MIC of liposomal lincomycin is eight times as low as usual lincomycin (0,23mkg/ml to 1,87 mkg/ml. Antibacterial activity of the liposomal form of lincomycin is studied concerning the patients selected from the different biotopes with pyo inflammatory diseases of staphylococcus strains (15 strains – methicillin sensitive, 12 strains - methicillin resistant.It is shown authentically the higher sensitivity of S. aureus strains to the liposomal form of lincomycin in comparison with usual lincomycin . Also 50.0% of MRSA strains were sensitive to the liposomalny form of lincomycin that shows the perspective for the development of the liposomal forms of antibiotics to cure staphylococcal infections.

  3. Liposome encapsulation of fluorescent nanoparticles: Quantum dots and silica nanoparticles

    International Nuclear Information System (INIS)

    Chen, C.-S.; Yao Jie; Durst, Richard A.

    2006-01-01

    Quantum dots (QDs) and silica nanoparticles (SNs) are relatively new classes of fluorescent probes that overcome the limitations encountered by organic fluorophores in bioassay and biological imaging applications. We encapsulated QDs and SNs in liposomes and separated nanoparticle-loaded liposomes from unencapsulated nanoparticles by size exclusion chromatography. Fluorescence correlation spectroscopy was used to measure the average number of nanoparticles inside each liposome. Results indicated that nanoparticle-loaded liposomes were formed and separated from unencapsulated nanoparticles by using a Sepharose gel. As expected, fluorescence self-quenching of nanoparticles inside liposomes was not observed. Each liposome encapsulated an average of three QDs. These studies demonstrated that nanoparticles could be successfully encapsulated into liposomes and provided a methodology to quantify the number of nanoparticles inside each liposome by fluorescence correlation spectroscopy

  4. Amperometric Adhesion Signals of Liposomes, Cells and Droplets

    OpenAIRE

    Ivošević DeNardis, N.; Žutić, V.; Svetličić, V.; Frkanec, R.

    2009-01-01

    Individual soft microparticles (liposomes, living cells and organic droplets) in aqueous media are characterized by their adhesion signals using amperometry at the dropping mercury electrode. We confirmed that the general mechanism established for adhesion of hydrocarbon droplets and cells is valid as well for liposome adhesion within a wide range of surface charge densities. Incidents and shape of adhesion signals in liposome suspensions reflect liposome polydispersity, surface charge den...

  5. Liposomal bupivacaine peripheral nerve block for the management of postoperative pain.

    Science.gov (United States)

    Hamilton, Thomas W; Athanassoglou, Vassilis; Trivella, Marialena; Strickland, Louise H; Mellon, Stephen; Murray, David; Pandit, Hemant G

    2016-08-25

    Postoperative pain remains a significant issue with poor perioperative pain management associated with an increased risk of morbidity and mortality. Liposomal bupivacaine is an analgesic consisting of bupivacaine hydrochloride encapsulated within multiple, non-concentric lipid bi-layers offering a novel method of sustained release. To assess the analgesic efficacy and adverse effects of liposomal bupivacaine infiltration peripheral nerve block for the management of postoperative pain. We identified randomised trials of liposomal bupivacaine peripheral nerve block for the management of postoperative pain. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 1), Ovid MEDLINE (1946 to January Week 1 2016), Ovid MEDLINE In-Process (14 January 2016), EMBASE (1974 to 13 January 2016), ISI Web of Science (1945 to 14 January 2016), and reference lists of retrieved articles. We sought unpublished studies from Internet sources, and searched clinical trials databases for ongoing trials. The date of the most recent search was 15 January 2016. Randomised, double-blind, placebo- or active-controlled clinical trials of a single dose of liposomal bupivacaine administered as a peripheral nerve block in adults aged 18 years or over undergoing elective surgery at any surgical site. We included trials if they had at least two comparison groups for liposomal bupivacaine peripheral nerve block compared with placebo or other types of analgesia. Two review authors independently considered trials for inclusion in the review, assessed risk of bias, and extracted data. We performed analyses using standard statistical techniques as described in the Cochrane Handbook for Systematic Reviews of Interventions, using Review Manager 5. We planned to perform a meta-analysis, however there were insufficient data to ensure a clinically meaningful answer; as such we have produced a 'Summary of findings' table in a narrative format, and where possible we assessed the

  6. Multifunctional liposomes for MRI and image-guided drug delivery

    NARCIS (Netherlands)

    Langereis, Sander; Hijnen, Nicole; Strijkers, Gustav; Nicolay, Klaas; Grüll, Holger

    2014-01-01

    Liposomes are a class of nanovesicles that have been explored extensively in the biomedical arena for early diagnosis and treatment of disease. In recent years, several liposomal drug formulations have been clinically approved in oncology. In a modular approach, the properties of liposomes can be

  7. Characterization of Diclofenac Liposomes Formulated with Palm Oil ...

    African Journals Online (AJOL)

    Purpose: To characterize diclofenac sodium (DS) liposomes prepared using palm oil fractions. Methods: Reverse-phase evaporation method was used to prepare liposomes containing 10, 20, 30 , 40 or 50% palm oil fractions. The effect of palm oil content on liposome formation, surface morphology, shape, size and zeta ...

  8. Evaluation of iron transport from ferrous glycinate liposomes using ...

    African Journals Online (AJOL)

    Background: Iron fortification of foods is currently a strategy employed to fight iron deficiency in countries. Liposomes were assumed to be a potential carrier of iron supplements. Objective: The objective of this study was to investigate the iron transport from ferrous glycinate liposomes, and to estimate the effects of liposomal ...

  9. Liposomal curcumin and its application in cancer

    Directory of Open Access Journals (Sweden)

    Feng T

    2017-08-01

    Full Text Available Ting Feng,1,* Yumeng Wei,1,* Robert J Lee,2 Ling Zhao1 1Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, People’s Republic of China; 2Division of Pharmaceutics, College of Pharmacy, The Ohio State University, Columbus, OH, USA *These authors contributed equally to this work Abstract: Curcumin (CUR is a yellow polyphenolic compound derived from the plant turmeric. It is widely used to treat many types of diseases, including cancers such as those of lung, cervices, prostate, breast, bone and liver. However, its effectiveness has been limited due to poor aqueous solubility, low bioavailability and rapid metabolism and systemic elimination. To solve these problems, researchers have tried to explore novel drug delivery systems such as liposomes, solid dispersion, microemulsion, micelles, nanogels and dendrimers. Among these, liposomes have been the most extensively studied. Liposomal CUR formulation has greater growth inhibitory and pro-apoptotic effects on cancer cells. This review mainly focuses on the preparation of liposomes containing CUR and its use in cancer therapy. Keywords: curcumin, liposomes, drug delivery, bioavailability, cancer 

  10. Treatment of Digital Ischemia with Liposomal Bupivacaine

    Directory of Open Access Journals (Sweden)

    José Raul Soberón

    2014-01-01

    Full Text Available Objective. This report describes a case in which the off-label use of liposomal bupivacaine (Exparel in a peripheral nerve block resulted in marked improvement of a patient’s vasoocclusive symptoms. The vasodilating and analgesic properties of liposomal bupivacaine in patients with ischemic symptoms are unknown, but our clinical experience suggests a role in the management of patients suffering from vasoocclusive disease. Case Report. A 45-year-old African American female was admitted to the hospital with severe digital ischemic pain. She was not a candidate for any vascular surgical or procedural interventions. Two continuous supraclavicular nerve blocks were placed with modest clinical improvement. These effects were also short-lived, with the benefits resolving after the discontinuation of the peripheral nerve blocks. She continued to report severe pain and was on multiple anticoagulant medications, so a decision was made to perform an axillary nerve block using liposomal bupivacaine (Exparel given the compressibility of the site as well as the superficial nature of the target structures. Conclusions. This case report describes the successful off-label usage of liposomal bupivacaine (Exparel in a patient with digital ischemia. Liposomal bupivacaine (Exparel is currently FDA approved only for wound infiltration use at this time.

  11. Tumor targeting using liposomal antineoplastic drugs

    Directory of Open Access Journals (Sweden)

    Jörg Huwyler

    2008-03-01

    Full Text Available Jörg Huwyler1, Jürgen Drewe2, Stephan Krähenbühl21University of Applied Sciences Northwestern Switzerland, Institute of Pharma Technology, Muttenz, Switzerland; 2Department of Research and Division of Clinical Pharmacology, University Hospital Basel, Basel, SwitzerlandAbstract: During the last years, liposomes (microparticulate phospholipid vesicles have beenused with growing success as pharmaceutical carriers for antineoplastic drugs. Fields of application include lipid-based formulations to enhance the solubility of poorly soluble antitumordrugs, the use of pegylated liposomes for passive targeting of solid tumors as well as vector-conjugated liposomal carriers for active targeting of tumor tissue. Such formulation and drug targeting strategies enhance the effectiveness of anticancer chemotherapy and reduce at the same time the risk of toxic side-effects. The present article reviews the principles of different liposomal technologies and discusses current trends in this field of research.Keywords: tumor targeting, antineoplastic drugs, liposomes, pegylation, steric stabilization, immunoliposomes

  12. Liposomal membrane disruption by means of miniaturized dielectric-barrier discharge in air: liposome characterization

    Science.gov (United States)

    Svarnas, P.; Asimakoulas, L.; Katsafadou, M.; Pachis, K.; Kostazos, N.; Antimisiaris, S. G.

    2017-08-01

    The increasing interest of the plasma community in the application of atmospheric-pressure cold plasmas to bio-specimen treatment has led to the creation of the emerging field of plasma biomedicine. Accordingly, plasma setups based on dielectric-barrier discharges have already been widely tested for the inactivation of various cells. Most of these systems refer to the plasma jet concept where noble gases penetrate atmospheric air and are subjected to the influence of high electric fields, thus forming guided streamers. Following the original works of our group where liposomal membranes were proposed as models for studying the interaction between plasma jets and cells, we present herein a study on liposomal membrane disruption by means of miniaturized dielectric-barrier discharge running in atmospheric air. Liposomal membranes of various lipid compositions, lamellarities, and sizes are treated at different times. It is shown that the dielectric-barrier discharge of low mean power leads to efficient liposomal membrane disruption. The latter is achieved in a controllable manner and depends on liposome properties. Additionally, it is clearly demonstrated that liposomal membrane disruption takes place even after plasma extinction, i.e. during post-treatment, resembling thus an ‘apoptosis’ effect, which is well known today mainly for cell membranes. Thus, the adoption of the present concept would be beneficial for tailoring studies on plasma-treated cell-mimics. Finally, the liposome treatment is discussed with respect to possible physicochemical mechanisms and potential discharge modification due to the various compositions of the liquid electrode.

  13. Lymphatic uptake and biodistribution of liposomes after subcutaneous injection - IV. Fate of liposomes in regional lymph nodes

    NARCIS (Netherlands)

    Oussoren, C; Scherphof, G; van der Want, JJ; van Rooijen, N; Storm, G

    1998-01-01

    The ability of clodronate-containing liposomes to deplete lymph nodes of macrophages was used as a tool to investigate the fate of liposomes in regional lymph nodes after subcutaneous (s.c.) administration. Reduced lymph node localization of liposomes in macrophage-depleted lymph nodes confirmed

  14. Radioprotective effectiveness of Adeturone, incapsulated in liposomes

    International Nuclear Information System (INIS)

    Pantev, T.

    1990-01-01

    The radioprotective properties of Adeturone (S,2-aminoethyl isothiuronic adenosine-5-triphosphate), incapsulated in mono- and tricomponent lisosomes was studied. Intraperitoneal adminisration of the radioprotector by means of monocomponent liposomes from egg lecithins, as well as of the radioprotector alone shortly before (15-30 min) gamma irradiation of mice with 7.5 Gy (LD 100/30 ) provided high survival rate - accordingly 80% and 75%. Orally administered Adeturone incapsulated in tricomponent liposomes (dipalmitoil-DL-3-lecithin:cholesterine:stearilamine - 7:2:1) protected mice exposed to lethal X-irradiation (7.8 Gy, LD 90/30 ) for 0.5 to 4.5 hours. Adeturone, applied alone under these conditions 4.5 hours before irradiation, was ineffective. The results clearly demonstrated a prolonged radioprotective effect of Adeturone, administered per os as liposome suspension. 2 tabs., 17 refs

  15. Liposome imaging agents in personalized medicine

    DEFF Research Database (Denmark)

    Petersen, Anncatrine Luisa; Hansen, Anders Elias; Gabizon, Alberto

    2012-01-01

    In recent years the importance of molecular and diagnostic imaging has increased dramatically in the treatment planning of many diseases and in particular in cancer therapy. Within nanomedicine there are particularly interesting possibilities for combining imaging and therapy. Engineered liposomes...... that selectively localize in tumor tissue can transport both drugs and imaging agents, which allows for a theranostic approach with great potential in personalized medicine. Radiolabeling of liposomes have for many years been used in preclinical studies for evaluating liposome in vivo performance and has been...... start to consider how to use imaging for patient selection and treatment monitoring in connection to nanocarrier based medicines. Nanocarrier imaging agents could furthermore have interesting properties for disease diagnostics and staging. Here, we review the major advances in the development...

  16. Immobilisation of impala (Aepyceros melampus with a ketamine hydrochloride / medetomidine hydrochloride combination, and reversal with atipamezole hydrochloride

    Directory of Open Access Journals (Sweden)

    M. Bush

    2004-06-01

    Full Text Available A combination of medetomidine hydrochloride (medetomidine and ketamine hydrochloride (ketamine was evaluated in 16 boma-confined and 19 free-ranging impalas (Aepyceros melampus to develop a non-opiate immobilisation protocol. In free-ranging impala a dose of 220 + 34 mg/kg medetomidine and 4.4 + 0.7 mg/kg ketamine combined with 7500 IU of hyaluronidase induced recumbency within 4.5+1.5 min, with good muscle relaxation, a stable heart rate and blood pH. PaCO2 was maintained within acceptable ranges. The animals were hypoxic with reduced oxygen saturation and low PaO2 in the presence of an elevated respiration rate, therefore methods for respiratory support are indicated. The depth of sedation was adequate for minor manipulations but additional anaesthesia is indicated for painful manipulations. Immobilisation was reversed by 467 + 108 mg/kg atipamezole hydrochloride (atipamezole intramuscularly, but re-sedation was observed several hours later, possibly due to a low atipamezole:medetomidine ratio of 2:1. Therefore, this immobilisation and reversal protocol would subject impalas to possible predation or conspecific aggression following reversal if they were released into the wild. If the protocol is used on free-ranging impala, an atipamezole:medetomidine ratio of 5:1 should probably be used to prevent re-sedation.

  17. Fluorescence Resonance Energy Transfer in Polydiacetylene Liposomes

    Science.gov (United States)

    Li, Xuelian; Matthews, Shelton; Kohli, Punit

    2009-01-01

    Conjugated polydiacetylene (PDA) possessing stimuli-responsive properties has been intensively investigated for developing efficient sensors. We report here fluorescence resonance energy transfer (FRET) in liposomes synthesized using different molar ratios of dansyl-tagged diacetylene and diacetylene–carboxylic acid monomers. Photopolymerization of diacetylene resulted in cross-linked PDA liposomes. We used steady-state electronic absorption, emission, and fluorescence anisotropy (FA) analysis to characterize the thermal-induced FRET between dansyl fluorophores (donor) and PDA (acceptor). We found that the monomer ratio of acceptor to donor (Rad) and length of linkers (functional part that connects dansyl fluorophores to the diacetylene group in the monomer) strongly affected FRET. For Rad = 10 000, the acceptor emission intensity was amplified by more than 18 times when the liposome solution was heated from 298 to 338 K. A decrease in Rad resulted in diminished acceptor emission amplification. This was primarily attributed to lower FRET efficiency between donors and acceptors and a higher background signal. We also found that the FRET amplification of PDA emissions after heating the solution was much higher when dansyl was linked to diacetylene through longer and flexible linkers than through shorter linkers. We attributed this to insertion of dansyl in the bilayer of the liposomes, which led to an increased dansyl quantum yield and a higher interaction of multiple acceptors with limited available donors. This was not the case for shorter and more rigid linkers where PDA amplification was much smaller. The present studies aim at enhancing our understanding of FRET between fluorophores and PDA-based conjugated liposomes. Furthermore, receptor tagged onto PDA liposomes can interact with ligands present on proteins, enzymes, and cells, which will produce emission sensing signal. Therefore, using the present approach, there exist opportunities for designing FRET

  18. Recent Trends of Polymer Mediated Liposomal Gene Delivery System

    Directory of Open Access Journals (Sweden)

    Shyamal Kumar Kundu

    2014-01-01

    Full Text Available Advancement in the gene delivery system have resulted in clinical successes in gene therapy for patients with several genetic diseases, such as immunodeficiency diseases, X-linked adrenoleukodystrophy (X-ALD blindness, thalassemia, and many more. Among various delivery systems, liposomal mediated gene delivery route is offering great promises for gene therapy. This review is an attempt to depict a portrait about the polymer based liposomal gene delivery systems and their future applications. Herein, we have discussed in detail the characteristics of liposome, importance of polymer for liposome formulation, gene delivery, and future direction of liposome based gene delivery as a whole.

  19. Liposomes for Use in Gene Delivery

    Directory of Open Access Journals (Sweden)

    Daniel A. Balazs

    2011-01-01

    Full Text Available Liposomes have a wide array of uses that have been continuously expanded and improved upon since first being observed to self-assemble into vesicular structures. These arrangements can be found in many shapes and sizes depending on lipid composition. Liposomes are often used to deliver a molecular cargo such as DNA for therapeutic benefit. The lipids used to form such lipoplexes can be cationic, anionic, neutral, or a mixture thereof. Herein physical packing parameters and specific lipids used for gene delivery will be discussed, with lipids classified according to overall charge.

  20. Liposomal cancer therapy: exploiting tumor characteristics

    DEFF Research Database (Denmark)

    Kaasgaard, Thomas; Andresen, Thomas Lars

    2010-01-01

    an overview of current strategies for improving the different stages of liposomal cancer therapy, which involve transporting drug-loaded liposomes through the bloodstream, increasing tumor accumulation, and improving drug release and cancer cell uptake after accumulation at the tumor target site. What...... the reader will gain: The review focuses on strategies that exploit characteristic features of solid tumors, such as abnormal vasculature, overexpression of receptors and enzymes, as well as acidic and thiolytic characteristics of the tumor microenvironment. Take home message: It is concluded that the design...

  1. Overcoming cellular and tissue barriers to improve liposomal drug delivery

    Science.gov (United States)

    Kohli, Aditya G.

    Forty years of liposome research have demonstrated that the anti-tumor efficacy of liposomal therapies is, in part, driven by three parameters: 1) liposome formulation and lipid biophysics, 2) accumulation and distribution in the tumor, and 3) release of the payload at the site of interest. This thesis outlines three studies that improve on each of these delivery steps. In the first study, we engineer a novel class of zwitterlipids with an inverted headgroup architecture that have remarkable biophysical properties and may be useful for drug delivery applications. After intravenous administration, liposomes accumulate in the tumor by the enhanced permeability and retention effect. However, the tumor stroma often limits liposome efficacy by preventing distribution into the tumor. In the second study, we demonstrate that depletion of hyaluronan in the tumor stroma improves the distribution and efficacy of DoxilRTM in murine 4T1 tumors. Once a liposome has distributed to the therapeutic site, it must release its payload over the correct timescale. Few facile methods exist to quantify the release of liposome therapeutics in vivo. In the third study, we outline and validate a simple, robust, and quantitative method for tracking the rate and extent of release of liposome contents in vivo. This tool should facilitate a better understanding of the pharmacodynamics of liposome-encapsulated drugs in animals. This work highlights aspects of liposome behavior that have prevented successful clinical translation and proposes alternative approaches to improve liposome drug delivery.

  2. Cartap hydrochloride poisoning: a case report

    OpenAIRE

    Sumesh Raj; Sheetal S.

    2014-01-01

    Cartap hydrochloride is a thiocarbamate insecticide used for control of chewing and sucking insects of all stages of development, on many crops. It is an analogue of nereistoxin. Poisoning with cartap is very rarely reported from India. We report a 46 year old man who consumed cartap with alcohol, presented with nausea & vomiting and improved with supportive measures. [Int J Res Med Sci 2014; 2(1.000): 360-361

  3. Aerosolized liposomes with dipalmitoyl phosphatidylcholine enhance pulmonary insulin delivery.

    Science.gov (United States)

    Chono, Sumio; Fukuchi, Rie; Seki, Toshinobu; Morimoto, Kazuhiro

    2009-07-20

    The pulmonary insulin delivery characteristics of liposomes were examined. Aerosolized liposomes containing insulin were administered into rat lungs and the enhancing effect on insulin delivery was evaluated by changes of plasma glucose levels. Liposomes with dipalmitoyl phosphatidylcholine (DPPC) enhanced pulmonary insulin delivery in rats, however, liposomes with dilauroyl, dimyristoyl, distearoyl or dioleoyl phosphatidylcholine did not. Liposomes with DPPC also enhanced the in vitro permeation of FITC dextran (Mw 4400, FD-4) through the calu-3 cell monolayer by reducing the transepithelial electrical resistance and did not harm lung tissues in rats. These findings suggest that liposomes with DPPC enhance pulmonary insulin delivery by opening the epithelial cell space in the pulmonary mucosa not mucosal cell damage. Liposomes with DPPC could be useful as a pulmonary delivery system for peptide and protein drugs.

  4. FORMULATION AND EVALUATION OF ISONIAZID AND ETHAMBUTOL HYDROCHLORIDE COMBINATION TABLETS

    OpenAIRE

    Margret Chandira R; Jayakar B; Palanisamy P.

    2012-01-01

    Ethambutol hydrochloride and Isoniazid Drugs are used as Antituberculosis agents. It is mainly used in the initial Treatment of pulmonary tuberculosis. Here in present study compressed tablet of Ethambutol hydrochloride and Isoniazid prepared by using HPMC, HPC, and PVPK -30 as binders. Compressed tablets of Ethambutol hydrochloride and Isoniazid were prepared by wet granulation method. Among different trials of F1 to F9 with wet granulation, the trial F1 showed satisfactory in-vitro drug re...

  5. Spectrophotometric determination of procainamide hydrochloride using sodium periodate

    OpenAIRE

    Al-Tamrah, S.; Al-Abbad, S.

    2015-01-01

    A simple spectrophotometric method has been described for the determination of procainamide hydrochloride. The method is based on the oxidation of procainamide hydrochloride by sodium periodate in the presence of sulfuric acid and measurement of the absorbance of the violet color formed at 531 nm. Parameters affecting the reaction were studied and conditions were optimized. Linear calibration graph was obtained from 50 to 700 μg ml−1 of procainamide hydrochloride and the limit of detection wa...

  6. Impact of local administration of liposome bupivacaine for postsurgical analgesia on wound healing: a review of data from ten prospective, controlled clinical studies.

    Science.gov (United States)

    Baxter, Richard; Bramlett, Kenneth; Onel, Erol; Daniels, Stephen

    2013-03-01

    Liposome bupivacaine is a liposomal formulation that allows delivery of bupivacaine for 96 hours with a single local administration. It is indicated for the management of postsurgical pain. This retrospective review of 10 clinical trials assessed the potential impact of local anesthetics on wound healing and chondrolysis. Various doses of liposome bupivacaine and bupivacaine hydrochloride (HCl) were evaluated. Primary inclusion criteria across the 10 Phase 2 and Phase 3 randomized, double-blind studies required that patients be ≥18 years of age at the screening visit and scheduled to undergo the specified surgical procedure in each study (inguinal hernia repair, total knee arthroplasty, hemorrhoidectomy, breast augmentation, or bunionectomy). Key exclusion criteria were: a history of clinically significant medical conditions (including cardiovascular, hepatic, renal, neurologic, psychiatric, or metabolic disease) or laboratory results that indicated an increased vulnerability to the study drugs and/or procedures; medical condition(s) or concurrent surgery that may have required analgesic treatment in the postoperative period for pain that was not strictly related to the study surgery; and/or any clinically significant event or condition discovered during surgery that could have complicated the patient's postsurgical course. Assessments included the clinician's overall satisfaction with the patient's wound healing, wound status (erythema, drainage, edema, and induration), and wound scarring. Adverse events (AEs) potentially manifesting as wound complications and local AEs were also assessed. In total, 823 patients received liposome bupivacaine at doses ranging from 66 to 532 mg across the 5 different surgical settings; 446 patients received bupivacaine HCl (75-200 mg), and 190 patients received placebo. Few studies showed statistically significant differences between liposome bupivacaine and the comparator (bupivacaine HCl or placebo) with regard to the clinician

  7. Preparation, characterization, and efficient transfection of cationic liposomes and nanomagnetic cationic liposomes

    Directory of Open Access Journals (Sweden)

    Samadikhah HR

    2011-10-01

    Full Text Available Hamid Reza Samadikhah1,*, Asia Majidi2,*, Maryam Nikkhah2, Saman Hosseinkhani11Department of Biochemistry, 2Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran *These authors contributed equally to this work Purpose: Cationic liposomes (CLs are composed of phospholipid bilayers. One of the most important applications of these particles is in drug and gene delivery. However, using CLs to deliver therapeutic nucleic acids and drugs to target organs has some problems, including low transfection efficiency in vivo. The aim of this study was to develop novel CLs containing magnetite to overcome the deficiencies. Patients and methods: CLs and magnetic cationic liposomes (MCLs were prepared using the freeze-dried empty liposome method. Luciferase-harboring vectors (pGL3 were transferred into liposomes and the transfection efficiencies were determined by luciferase assay. Firefly luciferase is one of most popular reporter genes often used to measure the efficiency of gene transfer in vivo and in vitro. Different formulations of liposomes have been used for delivery of different kinds of gene reporters. Lipoplex (liposome–plasmid DNA complexes formation was monitored by gel retardation assay. Size and charge of lipoplexes were determined using particle size analysis. Chinese hamster ovary cells were transfected by lipoplexes (liposome-pGL3; transfection efficiency and gene expression level was evaluated by luciferase assay. Results: High transfection efficiency of plasmid by CLs and novel nanomagnetic CLs was achieved. Moreover, lipoplexes showed less cytotoxicity than polyethyleneimine and Lipofectamine™. Conclusion: Novel liposome compositions (1,2-dipalmitoyl-sn-glycero-3-phosphocholine [DPPC]/dioctadecyldimethylammonium bromide [DOAB] and DPPC/cholesterol/DOAB with high transfection efficiency can be useful in gene delivery in vitro. MCLs can also be used for targeted gene delivery, due to

  8. Construction of a Liposome Dialyzer for preparation of high-value, small-volume liposome formulations

    OpenAIRE

    Adamala, Katarzyna; Engelhart, Aaron E.; Kamat, Neha P.; Jin, Lin; Szostak, Jack W.

    2015-01-01

    The liposome dialyzer is a small-volume equilibrium dialysis device, built from commercially available materials, that is designed for rapid exchange of small volumes of an extraliposomal reagent pool against a liposome preparation. The dialyzer is prepared by modification of commercially available dialysis cartridges and consists of a reactor with two 300 µL chambers and a 1.56 cm2 dialysis surface area. The dialyzer is prepared in three stages: 1) disassembly of dialysis cartridges to obtai...

  9. Spectrophotometric determination of procainamide hydrochloride using sodium periodate

    Directory of Open Access Journals (Sweden)

    S. Al-Tamrah

    2015-09-01

    Full Text Available A simple spectrophotometric method has been described for the determination of procainamide hydrochloride. The method is based on the oxidation of procainamide hydrochloride by sodium periodate in the presence of sulfuric acid and measurement of the absorbance of the violet color formed at 531 nm. Parameters affecting the reaction were studied and conditions were optimized. Linear calibration graph was obtained from 50 to 700 μg ml−1 of procainamide hydrochloride and the limit of detection was 25 μg ml−1. The method was successfully applied for the determination of procainamide hydrochloride in pharmaceutical preparation.

  10. Prospects of liposomes using for creating of new forms of the medicinal and preventive preparations

    Directory of Open Access Journals (Sweden)

    M. A. Kisjakova

    2010-07-01

    Full Text Available Information on the structure, physical and chemical characteristics of the phospholipid vesicles (liposomes – the effective natural drug delivery system is presented. Types of liposomes, procedures of its productions, penetration mechanisms into cells and functional features of liposomal drugs are described. Data on production of liposomes with lactobacilli acellular homogenates and the methods of the liposomes structure control asre demonstrated.

  11. Mechanical Division of Cell-Sized Liposomes

    NARCIS (Netherlands)

    Deshpande, S.R.; Kerssemakers, J.W.J.; Dekker, C.

    2018-01-01

    Liposomes, self-assembled vesicles with a lipid-bilayer boundary similar to cell membranes, are extensively used in both fundamental and applied sciences. Manipulation of their physical properties, such as growth and division, may significantly expand their use as model systems in cellular and

  12. Influence of the Encapsulation Efficiency and Size of Liposome on the Oral Bioavailability of Griseofulvin-Loaded Liposomes

    Directory of Open Access Journals (Sweden)

    Sandy Gim Ming Ong

    2016-08-01

    Full Text Available The objective of the present study was to investigate the influence of the encapsulation efficiency and size of liposome on the oral bioavailability of griseofulvin-loaded liposomes. Griseofulvin-loaded liposomes with desired characteristics were prepared from pro-liposome using various techniques. To study the effect of encapsulation efficiency, three preparations of griseofulvin, namely, griseofulvin aqueous suspension and two griseofulvin-loaded liposomes with different amounts of griseofulvin encapsulated [i.e., F1 (32% and F2(98%], were administered to rats. On the other hand, to study the effect of liposome size, the rats were given three different griseofulvin-loaded liposomes of various sizes, generated via different mechanical dispersion techniques [i.e., FTS (142 nm, MS (357 nm and NS (813 nm], but with essentially similar encapsulation efficiencies (about 93%. Results indicated that the extent of bioavailability of griseofulvin was improved 1.7–2.0 times when given in the form of liposomes (F1 compared to griseofulvin suspension. Besides that, there was an approximately two-fold enhancement of the extent of bioavailability following administration of griseofulvin-loaded liposomes with higher encapsulation efficiency (F2, compared to those of F1. Also, the results showed that the extent of bioavailability of liposomal formulations with smaller sizes were higher by approximately three times compared to liposomal formulation of a larger size. Nevertheless, a further size reduction of griseofulvin-loaded liposome (≤400 nm did not promote the uptake or bioavailability of griseofulvin. In conclusion, high drug encapsulation efficiency and small liposome size could enhance the oral bioavailability of griseofulvin-loaded liposomes and therefore these two parameters deserve careful consideration during formulation.

  13. Stimuli-Responsive Liposomes for Controlled Drug Delivery

    KAUST Repository

    Li, Wengang

    2014-09-01

    Liposomes are promising drug delivery vesicles due to their biodegradibility, large volume and biocompatibility towards both hydrophilic and hydrophobic drugs. They suffer, however, from poor stability which limits their use in controlled delivery applications. Herein, a novel method was devised for modification of liposomes with small molecules, polymers or nanoparticles to afford stimuli responsive systems that release on demand and stay relatively stable in the absence of the trigger.. This dissertation discusses thermosensitive, pH sensitive, light sensitive and magnetically triggered liposomes that have been prepared for controlled drug delivery application. RAFT polymerization was utilized for the preparation of thermosensitive liposomes (Cholesterol-PNIPAm) and acid-labile liposomes (DOPE-PAA). With low Mw Cholesterol-PNIPAm, the thermosensitive liposomes proved to be effective for controlled release and decreased the cytotoxicity of PNIPAm by eliciting the polymer doses. By crosslinking the DOPE-PAA on liposome surface with acid-labile diamine linkers, DOPE-PAA liposomes were verified to be sensitive at low pH. The effects of polymer structures (linear or hyperbranched) have also been studied for the stability and release properties of liposomes. Finally, a dual-responsive Au@SPIO embedded liposome hybrid (ALHs) was prepared with light-induced “on-and-off” function by photo-thermal process (visible light) and instant release properties triggered by alternating magnetic field, respectively. The ALH system would be further applied into the cellular imaging field as MRI contrast agent.

  14. Liposomal Conjugates for Drug Delivery to the Central Nervous System

    Directory of Open Access Journals (Sweden)

    Frieder Helm

    2015-04-01

    Full Text Available Treatments of central nervous system (CNS diseases often fail due to the blood–brain barrier. Circumvention of this obstacle is crucial for any systemic treatment of such diseases to be effective. One approach to transfer drugs into the brain is the use of colloidal carrier systems—amongst others, liposomes. A prerequisite for successful drug delivery by colloidal carriers to the brain is the modification of their surface, making them invisible to the reticuloendothelial system (RES and to target them to specific surface epitopes at the blood–brain barrier. This study characterizes liposomes conjugated with cationized bovine serum albumin (cBSA as transport vectors in vitro in porcine brain capillary endothelial cells (PBCEC and in vivo in rats using fluorescently labelled liposomes. Experiments with PBCEC showed that sterically stabilized (PEGylated liposomes without protein as well as liposomes conjugated to native bovine serum albumin (BSA were not taken up. In contrast, cBSA-liposomes were taken up and appeared to be concentrated in intracellular vesicles. Uptake occurred in a concentration and time dependent manner. Free BSA and free cBSA inhibited uptake. After intravenous application of cBSA-liposomes, confocal fluorescence microscopy of brain cryosections from male Wistar rats showed fluorescence associated with liposomes in brain capillary surrounding tissue after 3, 6 and 24 h, for liposomes with a diameter between 120 and 150 nm, suggesting successful brain delivery of cationized-albumin coupled liposomes.

  15. Effect of chitosan coating on the characteristics of DPPC liposomes

    Directory of Open Access Journals (Sweden)

    Mohsen M. Mady

    2010-07-01

    Full Text Available Because it is both biocompatible and biodegradable, chitosan has been used to provide a protective capsule in new drug formulations. The present work reports on investigations into some of the physicochemical properties of chitosan-coated liposomes, including drug release rate, transmission electron microscopy (TEM, zeta potential and turbidity measurement. It was found that chitosan increases liposome stability during drug release. The coating of DPPC liposomes with a chitosan layer was confirmed by electron microscopy and the zeta potential of liposomes. The coating of liposomes by chitosan resulted in a marginal increase in the size of the liposomes, adding a layer of (92 ± 27.1 nm. The liposomal zeta potential was found to be increasingly positive as chitosan concentration increased from 0.1% to 0.3% (w/v, before stabilising at a relatively constant value. Turbidity studies revealed that the coating of DPPC liposomes with chitosan did not significantly modify the main phase transition temperature of DPPC at examined chitosan concentrations. The appropriate combination of liposomal and chitosan characteristics may produce liposomes with specific, prolonged and controlled release.

  16. Bladder uptake of liposomes after intravesical administration occurs by endocytosis.

    Directory of Open Access Journals (Sweden)

    Bharathi Raja Rajaganapathy

    Full Text Available Liposomes have been used therapeutically and as a local drug delivery system in the bladder. However, the exact mechanism for the uptake of liposomes by bladder cells is unclear. In the present study, we investigated the role of endocytosis in the uptake of liposomes by cultured human UROtsa cells of urothelium and rat bladder. UROtsa cells were incubated in serum-free media with liposomes containing colloidal gold particles for 2 h either at 37°C or at 4°C. Transmission Electron Microscopy (TEM images of cells incubated at 37°C found endocytic vesicles containing gold inside the cells. In contrast, only extracellular binding was noticed in cells incubated with liposomes at 4°C. Absence of liposome internalization at 4°C indicates the need of energy dependent endocytosis as the primary mechanism of entry of liposomes into the urothelium. Flow cytometry analysis revealed that the uptake of liposomes at 37°C occurs via clathrin mediated endocytosis. Based on these observations, we propose that clathrin mediated endocytosis is the main route of entry for liposomes into the urothelial layer of the bladder and the findings here support the usefulness of liposomes in intravesical drug delivery.

  17. Accelerometric comparison of the locomotor pattern of horses sedated with xylazine hydrochloride, detomidine hydrochloride, or romifidine hydrochloride.

    Science.gov (United States)

    López-Sanromán, F Javier; Holmbak-Petersen, Ronald; Varela, Marta; del Alamo, Ana M; Santiago, Isabel

    2013-06-01

    To evaluate the duration of effects on movement patterns of horses after sedation with equipotent doses of xylazine hydrochloride, detomidine hydrochloride, or romifidine hydrochloride and determine whether accelerometry can be used to quantify differences among drug treatments. 6 healthy horses. Each horse was injected IV with saline (0.9% NaCl) solution (10 mL), xylazine diluted in saline solution (0.5 mg/kg), detomidine diluted in saline solution (0.01 mg/kg), or romifidine diluted in saline solution (0.04 mg/kg) in random order. A triaxial accelerometric device was used for gait assessment 15 minutes before and 5, 15, 30, 45, 60, 75, 90, 105, and 120 minutes after each treatment. Eight variables were calculated, including speed, stride frequency, stride length, regularity, dorsoventral power, propulsive power, mediolateral power, and total power; the force of acceleration and 3 components of power were then calculated. Significant differences were evident in stride frequency and regularity between treatments with saline solution and each α2-adrenoceptor agonist drug; in speed, dorsoventral power, propulsive power, total power, and force values between treatments with saline solution and detomidine or romifidine; and in mediolateral power between treatments with saline solution and detomidine. Stride length did not differ among treatments. Accelerometric evaluation of horses administered α2-adrenoceptor agonist drugs revealed more prolonged sedative effects of romifidine, compared with effects of xylazine or detomidine. Accelerometry could be useful in assessing the effects of other sedatives and analgesics. Accelerometric data may be helpful in drug selection for situations in which a horse's balance and coordination are important.

  18. 21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ketamine hydrochloride injectable dosage forms. 522.1222 Section 522.1222 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms. ...

  19. 21 CFR 524.1982 - Proparacaine hydrochloride ophthalmic solution.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Proparacaine hydrochloride ophthalmic solution... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.1982 Proparacaine hydrochloride ophthalmic solution. (a) Specifications. The drug is...

  20. Naratriptan hydrochloride in extemporaneosly compounded oral suspensions.

    Science.gov (United States)

    Zhang, Y P; Trissel, L A; Fox, J L

    2000-01-01

    The purpose of this study was to determine the pharmaceutical acceptability and chemical stability of naratriptan hydrochloride in three extemporaneously compounded suspension formulations. The naratriptan-hydrochloride oral suspensions were prepared from 2.5-mg commercial tablets yielding a nominal naratriptan concentration of 0.5 mg/mL. The suspension vehicles selected for testing were Syrpalta, an equal-parts mixture of Ora-Plus and Ora-Sweet, and an equal-parts mixture of Ora-Plus and Ora-Sweet SF. The tablets were crushed and thoroughly triturated to a fine powder using a porcelain mortar and pestle. The powder was incorporated into a portion of the Syrpalta or Ora-Plus suspension vehicle and mixed until homogeneous. The mixtures were then brought to volume with Syrpalta, Ora-Sweet or Ora-Sweet SF, as appropriate. The suspensions were packaged in amber, plastic, screw-cap prescription bottles and stored at 23 deg C for seven days and 4 deg C for 90 days. An adequate suspension was never achieved in Syrpalta. The crushed-tablet powder did not produce a uniformly dispersed mixture and exhibited clumping and a high rate of sedimentation. A distinct layer of the solid tablet material settled immediately after shaking. Over the next four hours, a densely packed, yellow, caked layer formed at the bottom of the containers, making resuspension difficult. During storage, the caking became worse. Chemical analysis was not performed. The Ora-Plus and Ora-Sweet or Ora-Sweet SF suspensions had a slight greenish cast and were resuspended without difficulty by shaking for approximately ten seconds, yielding easily poured and homogeneous mixtures throughout the study. Visible settling and layering did not begin for four hours with the Ora-Sweet suspension and 24 hours for the Ora-Sweet SF suspension. High pressure liquid chromatographic analysis found that the naratriptan concentration in both suspension-vehicle combinations exhibited little or no loss for seven days at 23

  1. Calcipotriol delivery into the skin with PEGylated liposomes

    DEFF Research Database (Denmark)

    Knudsen, Nina Østergaard; Rønholt, Stine; Salte, Ragnhild Djønne

    2012-01-01

    The d-vitamin analogue calcipotriol is commonly used for topical treatment of psoriasis, but skin penetration is required for calcipotriol to reach its pharmacological target: the keratinocytes in the lower epidermis. Liposomes can enhance the delivery of drugs into the skin, but a major challenge...... of the liposomes and the ability to deliver membrane-intercalated calcipotriol into the skin. Inclusion of 0.5, l and 5mol% PEG-DSPE in the membrane enhanced the colloidal stability of the liposomes without compromising the delivery of calcipotriol from the vehicle into excised pig skin. Calcipotriol...... to large multilamellar vesicles, indicating that the liposomes to some extent migrate as intact vesicles into the stratum corneum. However, calcipotriol penetrated the skin better than the lipid component of the liposomes, suggesting that at least a fraction of the drug is released from the liposomes...

  2. Advances and Challenges of Liposome Assisted Drug Delivery

    Directory of Open Access Journals (Sweden)

    Lisa eSercombe

    2015-12-01

    Full Text Available The application of liposomes to assist drug delivery has already had a major impact on many biomedical areas. They have been shown to be beneficial for stabilizing therapeutic compounds, overcoming obstacles to cellular and tissue uptake, and improving biodistribution of compounds to target sites in vivo. This enables effective delivery of encapsulated compounds to target sites while minimizing systemic toxicity. Liposomes present as an attractive delivery system due to their flexible physicochemical and biophysical properties, which allow easy manipulation to address different delivery considerations. Despite considerable research in the last 50 years and the plethora of positive results in preclinical studies, the clinical translation of liposome assisted drug delivery platforms has progressed incrementally. In this review, we will discuss the advances in liposome assisted drug delivery, biological challenges that still remain, and current clinical and experimental use of liposomes for biomedical applications. The translational obstacles of liposomal technology will also be presented.

  3. Liposome-based drug delivery in breast cancer treatment

    International Nuclear Information System (INIS)

    Park, John W

    2002-01-01

    Drug delivery systems can in principle provide enhanced efficacy and/or reduced toxicity for anticancer agents. Long circulating macromolecular carriers such as liposomes can exploit the 'enhanced permeability and retention' effect for preferential extravasation from tumor vessels. Liposomal anthracyclines have achieved highly efficient drug encapsulation, resulting in significant anticancer activity with reduced cardiotoxicity, and include versions with greatly prolonged circulation such as liposomal daunorubicin and pegylated liposomal doxorubicin. Pegylated liposomal doxorubucin has shown substantial efficacy in breast cancer treatment both as monotherapy and in combination with other chemotherapeutics. Additional liposome constructs are being developed for the delivery of other drugs. The next generation of delivery systems will include true molecular targeting; immunoliposomes and other ligand-directed constructs represent an integration of biological components capable of tumor recognition with delivery technologies

  4. Comparative Efficacy Of 1% Terbinafine Hydrochloride And 1% Butenafine Hydrochloride Cream In The Treatment Of Tinea Cruris

    Directory of Open Access Journals (Sweden)

    Rathi Sanjay K

    2001-01-01

    Full Text Available The aim of the study was to evaluate the comparative efficacy of 1% terbinafine hydrochloride and 1% butenafine hydrochloride cream in the treatment of Tinea cruris, was done taking with ten patients in each study group. They were found to be equipotent in one and two weeks treatment respectively.

  5. Pharmacokinetics of a 5-fluorouracil liposomal delivery system.

    OpenAIRE

    Simmons, S T; Sherwood, M B; Nichols, D A; Penne, R B; Sery, T; Spaeth, G L

    1988-01-01

    A liposomal delivery system was developed in an attempt to prolong ocular levels of 5-fluorouracil for glaucoma filtering surgery. The pharmacokinetics of the 5-fluorouracil liposomal delivery system were studied in normal pigmented rabbits with 5-fluorouracil labelled with carbon-14 (C-14). 14C 5-fluorouracil was incorporated into the liposomes at a concentration of 10 g/l and injected subconjunctivally in doses of 5 and 10 mg. Concentrations of 5-fluorouracil were assayed at 10 time interva...

  6. Novel liposomal technology applied in esophageal cancer treatment

    Science.gov (United States)

    Yeh, Chia-Hsien; Hsieh, Yei-San; Yang, Pei-wen; Huang, Leaf; Hsu, Yih-Chih

    2018-02-01

    Cisplatin (CDDP) has been commonly used as a chemotherapeutic drug, mainly used for the treatment of malignant epithelial cell tumors. We have developed a new method based on innovative lipid calcium phosphate, which encapsulated hydrophobic drugs to form liposomal nanoparticles. Esophageal cancer xenograft model was used to investigate the efficacy of liposomal nanoparticles. and it showed good therapeutic efficacy with lower side effects. Liposomal nanoparticles exhibited a better therapeutic effect than that of conventional CDDP.

  7. Liposomes: structure, properties and methods of curative administration in organism

    Directory of Open Access Journals (Sweden)

    M. A. Kisyakova

    2010-07-01

    Full Text Available A review of data from scientific sources, devoted to problems of liposomes’ structure, properties and processes of formation was made. Advantages of liposomes used for medical purposes are shown. Methods of liposomes administration in an organism are characterised. Data on mechanisms of interaction between liposomes and cells, peculiarities of liposomes’ lipids composition and dependence of its tropism to definite organs and tissues are generalised.

  8. pH-triggered echogenicity and contents release from liposomes.

    Science.gov (United States)

    Nahire, Rahul; Hossain, Rayat; Patel, Rupa; Paul, Shirshendu; Meghnani, Varsha; Ambre, Avinash H; Gange, Kara N; Katti, Kalpana S; Leclerc, Estelle; Srivastava, D K; Sarkar, Kausik; Mallik, Sanku

    2014-11-03

    Liposomes are representative lipid nanoparticles widely used for delivering anticancer drugs, DNA fragments, or siRNA to cancer cells. Upon targeting, various internal and external triggers have been used to increase the rate for contents release from the liposomes. Among the internal triggers, decreased pH within the cellular lysosomes has been successfully used to enhance the rate for releasing contents. However, imparting pH sensitivity to liposomes requires the synthesis of specialized lipids with structures that are substantially modified at a reduced pH. Herein, we report an alternative strategy to render liposomes pH sensitive by encapsulating a precursor which generates gas bubbles in situ in response to acidic pH. The disturbance created by the escaping gas bubbles leads to the rapid release of the encapsulated contents from the liposomes. Atomic force microscopic studies indicate that the liposomal structure is destroyed at a reduced pH. The gas bubbles also render the liposomes echogenic, allowing ultrasound imaging. To demonstrate the applicability of this strategy, we have successfully targeted doxorubicin-encapsulated liposomes to the pancreatic ductal carcinoma cells that overexpress the folate receptor on the surface. In response to the decreased pH in the lysosomes, the encapsulated anticancer drug is efficiently released. Contents released from these liposomes are further enhanced by the application of continuous wave ultrasound (1 MHz), resulting in substantially reduced viability for the pancreatic cancer cells (14%).

  9. Improved Antitumor Efficacy and Pharmacokinetics of Bufalin via PEGylated Liposomes

    Science.gov (United States)

    Yuan, Jiani; Zhou, Xuanxuan; Cao, Wei; Bi, Linlin; Zhang, Yifang; Yang, Qian; Wang, Siwang

    2017-11-01

    Bufalin was reported to show strong pharmacological effects including cardiotonic, antiviral, immune-regulation, and especially antitumor effects. The objective of this study was to determine the characterization, antitumor efficacy, and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity, which were prepared by FDA-approved pharmaceutical excipients. Bufalin-loaded PEGylated liposomes and bufalin-loaded liposomes were prepared reproducibly with homogeneous particle size by the combination of thin film evaporation method and high-pressure homogenization method. Their mean particle sizes were 127.6 and 155.0 nm, mean zeta potentials were 2.24 and - 18.5 mV, and entrapment efficiencies were 76.31 and 78.40%, respectively. In vitro release profile revealed that the release of bufalin in bufalin-loaded PEGylated liposomes was slower than that in bufalin-loaded liposomes. The cytotoxicity of blank liposomes has been found within acceptable range, whereas bufalin-loaded PEGylated liposomes showed enhanced cytotoxicity to U251 cells compared with bufalin entity. In vivo pharmacokinetics indicated that bufalin-loaded PEGylated liposomes could extend or eliminate the half-life time of bufalin in plasma in rats. The results suggested that bufalin-loaded PEGylated liposomes improved the solubility and increased the drug concentration in plasma.

  10. Liposomal Bupivacaine Injection Technique in Total Knee Arthroplasty.

    Science.gov (United States)

    Meneghini, R Michael; Bagsby, Deren; Ireland, Philip H; Ziemba-Davis, Mary; Lovro, Luke R

    2017-01-01

    Liposomal bupivacaine has gained popularity for pain control after total knee arthroplasty (TKA), yet its true efficacy remains unproven. We compared the efficacy of two different periarticular injection (PAI) techniques for liposomal bupivacaine with a conventional PAI control group. This retrospective cohort study compared consecutive patients undergoing TKA with a manufacturer-recommended, optimized injection technique for liposomal bupivacaine, a traditional injection technique for liposomal bupivacaine, and a conventional PAI of ropivacaine, morphine, and epinephrine. The optimized technique utilized a smaller gauge needle and more injection sites. Self-reported pain scores, rescue opioids, and side effects were compared. There were 41 patients in the liposomal bupivacaine optimized injection group, 60 in the liposomal bupivacaine traditional injection group, and 184 in the conventional PAI control group. PAI liposomal bupivacaine delivered via manufacturer-recommended technique offered no benefit over PAI ropivacaine, morphine, and epinephrine. Mean pain scores and the proportions reporting no or mild pain, time to first opioid, and amount of opioids consumed were not better with PAI liposomal bupivacaine compared with PAI ropivacaine, morphine, and epinephrine. The use of the manufacturer-recommended technique for PAI of liposomal bupivacaine does not offer benefit over a conventional, less expensive PAI during TKA. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  11. FDA Approves Irinotecan Liposome to Treat Pancreatic Cancer

    Science.gov (United States)

    Patients with metastatic pancreatic cancer that has progressed after receiving gemcitabine-based chemotherapy now have a new treatment option: irinotecan liposome in combination with fluorouracil and leucovorin.

  12. Liposome as nanocarrier: Site targeted delivery in lung cancer

    Directory of Open Access Journals (Sweden)

    Najeeb Ullah

    2017-08-01

    Full Text Available Lung cancer is fatal and spreading rapidly worldwide. Different clinical strategies are applied to stop this cancer. As the lung is a delicate organ, special clinical applications must be used and nanodrugs delivery systems are the most important applications of all. This review discusses the lung problems such as lung cancer, lung inflammation and bronchi constrictions followed by repetitive intake of some drugs. The objective of this review is to study how nanodrug delivery systems were synthesized and used in lung disorder treatment especially in lung cancer. The authors studied some articles from 1989 to 2015. Liposome encapsulation was done in various ways for the delivery of different drugs such as metaproterenol into liposomes caused bronchodilation, immunoliposomes bearing antibodies for doxorubicin reduced 50% inhibitory effects, radioliposomes with high penetrating ability to peripheral airways, aerosol delivery systems with deep pulmonary deposition, polymeric drug delivery having potential to improve beneficial index of drug, solid lipid liposomes, liposomal gentamicin with altered different clinical susceptibilities of resistance, transferrin conjugated liposomes to deliver cytostatic drugs to site of lungs, anti-inflammatory drugs with mannosylated liposomes, liposomal suspensions with single stranded RNAs and peptide encapsulation of liposomes. This review indicates that many animals perished with intravenous administration of drugs but survived in liposomal targeting groups.

  13. Silica-Coated Liposomes for Insulin Delivery

    OpenAIRE

    Neelam Dwivedi; M. A. Arunagirinathan; Somesh Sharma; Jayesh Bellare

    2010-01-01

    Liposomes coated with silica were explored as protein delivery vehicles for their enhanced stability and improved encapsulation efficiency. Insulin was encapsulated within the fluidic phosphatidylcholine lipid vesicles by thin film hydration at pH 2.5, and layer of silica was formed above lipid bilayer by acid catalysis. The presence of silica coating and encapsulated insulin was identified using confocal and electron microscopy. The native state of insulin present in the formulation was evid...

  14. Interaction of cationic drugs with liposomes.

    Science.gov (United States)

    Howell, Brett A; Chauhan, Anuj

    2009-10-20

    Interactions between cationic drugs and anionic liposomes were studied by measuring binding of drugs and the effect of binding on liposome permeability. The measurements were analyzed in the context of a continuum model based on electrostatic interactions and a Langmuir isotherm. Experiments and modeling indicate that, although electrostatic interactions are important, the fraction of drug sequestered in the double-layer is negligible. The majority of drug enters the bilayer with the charged regions interacting with the charged lipid head groups and the lipophilic regions associated with the bilayer. The partitioning of the drug can be described by a Langmuir isotherm with the electrostatic interactions increasing the sublayer concentration of the drug. The binding isotherms are similar for all tricyclic antidepressants (TCA). Bupivacaine (BUP) binds significantly less compared to TCA because its structure is such that the charged region has minimal interactions with the lipid heads once the BUP molecule partitions inside the bilayer. Conversely, the TCAs are linear with distinct hydrophilic and lipophilic regions, allowing the lipophilic regions to lie inside the bilayer and the hydrophilic regions to protrude out. This conformation maximizes the permeability of the bilayer, leading to an increased release of a hydrophilic fluorescent dye from liposomes.

  15. Oxygen Measurements in Liposome Encapsulated Hemoglobin

    Science.gov (United States)

    Phiri, Joshua Benjamin

    Liposome encapsulated hemoglobins (LEH's) are of current interest as blood substitutes. An analytical methodology for rapid non-invasive measurements of oxygen in artificial oxygen carriers is examined. High resolution optical absorption spectra are calculated by means of a one dimensional diffusion approximation. The encapsulated hemoglobin is prepared from fresh defibrinated bovine blood. Liposomes are prepared from hydrogenated soy phosphatidylcholine (HSPC), cholesterol and dicetylphosphate using a bath sonication method. An integrating sphere spectrophotometer is employed for diffuse optics measurements. Data is collected using an automated data acquisition system employing lock-in -amplifiers. The concentrations of hemoglobin derivatives are evaluated from the corresponding extinction coefficients using a numerical technique of singular value decomposition, and verification of the results is done using Monte Carlo simulations. In situ measurements are required for the determination of hemoglobin derivatives because most encapsulation methods invariably lead to the formation of methemoglobin, a nonfunctional form of hemoglobin. The methods employed in this work lead to high resolution absorption spectra of oxyhemoglobin and other derivatives in red blood cells and liposome encapsulated hemoglobin (LEH). The analysis using singular value decomposition method offers a quantitative means of calculating the fractions of oxyhemoglobin and other hemoglobin derivatives in LEH samples. The analytical methods developed in this work will become even more useful when production of LEH as a blood substitute is scaled up to large volumes.

  16. Ultrasound effects on brain-targeting mannosylated liposomes: in vitro and blood–brain barrier transport investigations

    Directory of Open Access Journals (Sweden)

    Zidan AS

    2015-07-01

    Full Text Available Ahmed S Zidan,1,2 Hibah Aldawsari1 1Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia; 2Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt Abstract: Delivering drugs to intracerebral regions can be accomplished by improving the capacity of transport through blood–brain barrier. Using sertraline as model drug for brain targeting, the current study aimed at modifying its liposomal vesicles with mannopyranoside. Box-Behnken design was employed to statistically optimize the ultrasound parameters, namely ultrasound amplitude, time, and temperature, for maximum mannosylation capacity, sertraline entrapment, and surface charge while minimizing vesicular size. Moreover, in vitro blood–brain barrier transport model was established to assess the transendothelial capacity of the optimized mannosylated vesicles. Results showed a dependence of vesicular size, mannosylation capacity, and sertraline entrapment on cavitation and bubble implosion events that were related to ultrasound power amplitude, temperature. However, short ultrasound duration was required to achieve >90% mannosylation with nanosized vesicles (<200 nm of narrow size distribution. Optimized ultrasound parameters of 65°C, 27%, and 59 seconds for ultrasound temperature, amplitude, and time were elucidated to produce 81.1%, 46.6 nm, and 77.6% sertraline entrapment, vesicular size, and mannosylation capacity, respectively. Moreover, the transendothelial ability was significantly increased by 2.5-fold by mannosylation through binding with glucose transporters. Hence, mannosylated liposomes processed by ultrasound could be a promising approach for manufacturing and scale-up of brain-targeting liposomes. Keywords: CNS delivery, sizing, lipid based formulations, quality by design, sertraline hydrochloride

  17. [Preparation of diclofenac sodium liposomes and its ocular pharmacokinetics].

    Science.gov (United States)

    Sun, Kao-xiang; Wang, Ai-ping; Huang, Li-jun; Liang, Rong-cai; Liu, Ke

    2006-11-01

    To prepare diclofenac sodium liposomes and observe its ocular pharmacokinetics in rabbits. The diclofenac sodium cationic liposomes were prepared by reverse-phase evaporation methods and the formula of liposome was optimized with uniform design. HPLC method was established and validated for the determination of diclofenac sodium in precornea, cornea and aqueous humor of rabbit eye. Liposome and eyedrop solution 50 microL with total 50 microg diclofenac sodium were instilled to eyes of rabbits, separately. Samples of tear, cornea and aqueous humor were collected at different time intervals after rabbits were sacrificed. The ocular pharmacokinetics was investigated by the concentration-time data of tear, cornea and aqueous humor. The mean particle size of the diclofenac sodium liposomes was 226.5 nm with zeta potential of + 18. 1 mV. The entrapment efficiency reached 63%. Compared with solution, liposome was characterized by slower clearance in precornea. The concentration of diclotenac in cornea and aqueous humor instilled with liposome were higher than that with eye-drop solution. Cmax of diclofenac sodium in aqueous humor instilled with liposome and eye-drop solution were (0.69 +/- 0.25) and (0.48 +/- 0.19) microg x mL(-1) and (36.68 +/- 11.7) and (21.82 +/- 8.6) microg x g(-1) in cornea, respectively. But no significant difference were found to Tmax in aqueous humor and cornea between liposome and eyedrop, T(1/2) of diclofenac in aqueous humor and cornea with liposoine were longer than that with eye-drop solution. The ocular bioavailability of liposome in aqueous humor was 211% compared with that of eyedrop. Diclofenac sodium cationic liposomes can increase the corneal contact time, enhance the corneal permeability of diclofenac sodium and improve its ocular bioavailability.

  18. Binding of Diphtheria Toxin to Phospholipids in Liposomes

    Science.gov (United States)

    Alving, Carl R.; Iglewski, Barbara H.; Urban, Katharine A.; Moss, Joel; Richards, Roberta L.; Sadoff, Jerald C.

    1980-04-01

    Diphtheria toxin bound to the phosphate portion of some, but not all, phospholipids in liposomes. Liposomes consisting of dimyristoyl phosphatidylcholine and cholesterol did not bind toxin. Addition of 20 mol% (compared to dimyristoyl phosphatidylcholine) of dipalmitoyl phosphatidic acid, dicetyl phosphate, phosphatidylinositol phosphate, cardiolipin, or phosphatidylserine in the liposomes resulted in substantial binding of toxin. Inclusion of phosphatidylinositol in dimyristol phosphatidylcholine / cholesterol liposomes did not result in toxin binding. The calcium salt of dipalmitoyl phosphatidic acid was more effective than the sodium salt, and the highest level of binding occurred with liposomes consisting only of dipalmitoyl phosphatidic acid (calcium salt) and cholesterol. Binding of toxin to liposomes was dependent on pH, and the pattern of pH dependence varied with liposomes having different compositions. Incubation of diphtheria toxin with liposomes containing dicetyl phosphate resulted in maximal binding at pH 3.6, whereas binding to liposomes containing phosphatidylinositol phosphate was maximal above pH 7. Toxin did not bind to liposomes containing 20 mol% of a free fatty acid (palmitic acid) or a sulfated lipid (3-sulfogalactosylceramide). Toxin binding to dicetyl phosphate or phosphatidylinositol phosphate was inhibited by UTP, ATP, phosphocholine, or p-nitrophenyl phosphate, but not by uracil. We conclude that (a) diphtheria toxin binds specifically to the phosphate portion of certain phospholipids, (b) binding to phospholipids in liposomes is dependent on pH, but is not due only to electrostatic interaction, and (c) binding may be strongly influenced by the composition of adjacent phospholipids that do not bind toxin. We propose that a minor membrane phospholipid (such as phosphatidylinositol phosphate or phosphatidic acid), or that some other phosphorylated membrane molecule (such as a phosphoprotein) may be important in the initial binding of

  19. Spectrophotometric method of the determination of gold (III) by using imipramine hydrochloride and promethazine hydrochloride

    International Nuclear Information System (INIS)

    Dembinski, B.; Kurzawa, M.; Szydlowska-Czerniak, A.

    2003-01-01

    Imipramine hydrochloride (IPM.HCl) and promethazine hydrochloride (PMT-HCl) were used for the spectrophotometric determination of gold (III) in the aqueous solution. The halides complexes of gold (III) created a coloured coupling with the studied drugs which were extractable in chloroform. These new compounds were characterized by IR,UV-VIS spectra and thermal and elemental analysis. Rapid and sensitive spectrophotometric method for the determination of gold (III) in the aqueous solution is described. The absorbance was found to be linear function of the gold (III) concentration in the range from 0.2 to 20 x10/sup -1/ mg. The ratio of complex (AuX/sub 4/) to the organic cation from drug in the obtained compounds was determined as 1:1. The method was satisfactorily applied to the analysis of gold (III). A great advantage of the proposed method is that the trace amounts of gold (III) can also be examined. (author)

  20. Preparation of liposomal amiodarone and investigation of its cardiomyocyte-targeting ability in cardiac radiofrequency ablation rat model

    Directory of Open Access Journals (Sweden)

    Zhuge Y

    2016-05-01

    Full Text Available Ying Zhuge,1,* Zhi-Feng Zheng,1,* Mu-Qing Xie,2 Lin Li,2 Fang Wang,1 Feng Gao2,3 1Department of Cardiology, Shanghai First People’s Hospital of Nanjing Medical University, 2Department of Pharmaceutics, School of Pharmacy, 3Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai, People’s Republic of China*These authors contributed equally to this workAbstract: The objective of this study was to develop an amiodarone hydrochloride (ADHC-loaded liposome (ADHC-L formulation and investigate its potential for cardiomyocyte targeting after cardiac radiofrequency ablation (CA in vivo. The ADHC-L was prepared by thin-film method combined with ultrasonication and extrusion. The preparation process was optimized by Box–Behnken design with encapsulation efficiency as the main evaluation index. The optimum formulation was quantitatively obtained with a diameter of 99.9±0.4 nm, a zeta potential of 35.1±10.9 mV, and an encapsulation efficiency of 99.5%±13.3%. Transmission electron microscopy showed that the liposomes were spherical particles with integrated bilayers and well dispersed with high colloidal stability. Pharmacokinetic studies were investigated in rats after intravenous administration, which revealed that compared with free ADHC treatment, ADHC-L treatment showed a 5.1-fold increase in the area under the plasma drug concentration–time curve over a period of 24 hours (AUC0–24 h and an 8.5-fold increase in mean residence time, suggesting that ADHC-L could facilitate drug release in a more stable and sustained manner while increasing the circulation time of ADHC, especially in the blood. Biodistribution studies of ADHC-L demonstrated that ADHC concentration in the heart was 4.1 times higher after ADHC-L treatment in CA rat model compared with ADHC-L sham-operated treatment at 20 minutes postinjection. Fluorescence imaging studies further proved that the heart

  1. Recent advances in liposomal nanohybrid cerasomes as promising drug nanocarriers.

    Science.gov (United States)

    Yue, Xiuli; Dai, Zhifei

    2014-05-01

    Liposomes have been extensively investigated as possible carriers for diagnostic or therapeutic agents due to their unique properties. However, liposomes still have not attained their full potential as drug and gene delivery vehicles because of their insufficient morphological stability. Recently, a super-stable and freestanding hybrid liposomal cerasome (partially ceramic- or silica-coated liposome) has drawn much attention as a novel drug delivery system because its atomic layer of polyorganosiloxane surface imparts higher morphological stability than conventional liposomes and its liposomal bilayer structure reduces the overall rigidity and density greatly compared to silica nanoparticles. Cerasomes are more biocompatible than silica nanoparticles due to the incorporation of the liposomal architecture into cerasomes. Cerasomes combine the advantages of both liposomes and silica nanoparticles but overcome their disadvantages so cerasomes are ideal drug delivery systems. The present review will first highlights some of the key advances of the past decade in the technology of cerasome production and then review current biomedical applications of cerasomes, with a view to stimulating further research in this area of study. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Fluorescence studies on gamma irradiated egg lecithin liposomal membrane

    International Nuclear Information System (INIS)

    Pandey, B.N.; Mishra, K.P.

    1998-01-01

    Alterations in structure and organization of sonicated EYL liposomal vesicular membrane after irradiation was investigated by DPH fluorescence probe which is a well known reporter for the environment of hydrophobic interior of membrane. Results of present study have demonstrated that loss of DPH fluorescence in liposomal membrane is linked to free radical mediated structural alterations possibly rigidization in the lipid bilayer

  3. The clearance of liposomes administered by the intramuscular route

    International Nuclear Information System (INIS)

    Arrowsmith, M.; Mills, S.N.

    1982-01-01

    Iodine 131-labelled lecithin was used to label liposomes entrapping cortisone-21-palmitate. The lecithin was injected into the fascia latae muscles of rabbits and the percentage of the initial dose remaining at certain time intervals was calculated from gamma camera image data. Release from the intramuscular site occurs by diffusion from intact liposomes. (U.K.)

  4. Structural properties of liposomes from digital holographic microscopy

    Science.gov (United States)

    Di Maio, Isabelle L.; Carl, Daniel; Langehanenberg, Patrik; Valenzuela, Stella M.; Battle, Andrew R.; Al Khazaaly, Sabah; Killingsworth, Murray; Kemper, Bjorn; von Bally, Gert; Martin, Donald K.

    2006-01-01

    We have constructed liposomes from L alpha Phosphatidylcholine (PC) lipids, which are biomimetic lipids similar to those present in the membranes of mammalian cells. We propose an advance in the use of liposomes, such as for drug delivery, to incorporate into the liposomal membranes transport proteins that have been extracted from the lipid membranes of mammalian cells. In this paper, we describe the usage of a novel optical microscope to characterize the nanomechanical properties of these liposomes. We have applied the technique of digital holographic microscopy, using an instrument recently developed at the University of Münster, Germany. This system enabled us to measure quantitatively the structural changes in liposomes. We have investigated the deformations of these biomimetic lipids comprising these liposomes by applying osmotic stresses, in order to gain insight into the membrane environment prior to incorporation of cloned membrane transport proteins. This control of the nanomechanical properties is important in the stresses transmitted to mechanosensitive ion channels that we have incorporated into the liposomal membranes. These liposomes provide transporting vesicles that respond to mechanical stresses, such as those that occur during implantation.

  5. 64Cu loaded liposomes as positron emission tomography imaging agents

    DEFF Research Database (Denmark)

    Petersen, Anncatrine Luisa; Binderup, Tina; Rasmussen, Palle

    2011-01-01

    applicable as PET imaging agents. We show the utility of the 64Cu-liposomes for quantitative in vivo imaging of healthy and tumor-bearing mice using PET. This remote loading method is a powerful tool for characterizing the in vivo performance of liposome based nanomedicine, and has great potential...

  6. BODIPY-based fluorescent liposomes with sesquiterpene lactone trilobolide

    Directory of Open Access Journals (Sweden)

    Ludmila Škorpilová

    2017-07-01

    Full Text Available Like thapsigargin, which is undergoing clinical trials, trilobolide is a natural product with promising anticancer and anti-inflammatory properties. Similar to thapsigargin, it has limited aqueous solubility that strongly reduces its potential medicinal applications. The targeted delivery of hydrophobic drugs can be achieved using liposome-based carriers. Therefore, we designed a traceable liposomal drug delivery system for trilobolide. The fluorescent green-emitting dye BODIPY, cholesterol and trilobolide were used to create construct 6. The liposomes were composed of dipalmitoyl-3-trimethylammoniumpropane and phosphatidylethanolamine. The whole system was characterized by atomic force microscopy, the average size of the liposomes was 150 nm in width and 30 nm in height. We evaluated the biological activity of construct 6 and its liposomal formulation, both of which showed immunomodulatory properties in primary rat macrophages. The uptake and intracellular distribution of construct 6 and its liposomal formulation was monitored by means of live-cell fluorescence microscopy in two cancer cell lines. The encapsulation of construct 6 into the liposomes improved the drug distribution in cancer cells and was followed by cell death. This new liposomal trilobolide derivative not only retains the biological properties of pure trilobolide, but also enhances the bioavailability, and thus has potential for the use in theranostic applications.

  7. Polyelectrolyte stabilized multilayered liposomes for oral delivery of paclitaxel

    DEFF Research Database (Denmark)

    Jain, Sanyog; Kumar, Dinesh; Swarnakar, Nitin K

    2012-01-01

    Paclitaxel (PTX) loaded layersome formulations were prepared using layer-by-layer assembly of the polyelectrolytes over liposomes. Stearyl amine was utilized to provide positive charge to the liposomes, which were subsequently coated with anionic polymer polyacrylic acid (PAA) followed by coating...

  8. Liposomal delivery of radionuclides for cancer diagnostics and radiotherapy

    DEFF Research Database (Denmark)

    Petersen, Anncatrine Luisa

    , an in vivo study is presented, where passive tumor accumulation of 64Cu loaded liposomes (64Cu-liposomes) in tumor-bearing mice was quantified directly by PET and computed tomography (CT) imaging. Furthermore, Article I present an evaluation and quantitative measurement of the biodistribution of 64Cu...

  9. Optimization and characterization of liposome formulation by mixture design.

    Science.gov (United States)

    Maherani, Behnoush; Arab-tehrany, Elmira; Kheirolomoom, Azadeh; Reshetov, Vadzim; Stebe, Marie José; Linder, Michel

    2012-02-07

    This study presents the application of the mixture design technique to develop an optimal liposome formulation by using the different lipids in type and percentage (DOPC, POPC and DPPC) in liposome composition. Ten lipid mixtures were generated by the simplex-centroid design technique and liposomes were prepared by the extrusion method. Liposomes were characterized with respect to size, phase transition temperature, ζ-potential, lamellarity, fluidity and efficiency in loading calcein. The results were then applied to estimate the coefficients of mixture design model and to find the optimal lipid composition with improved entrapment efficiency, size, transition temperature, fluidity and ζ-potential of liposomes. The response optimization of experiments was the liposome formulation with DOPC: 46%, POPC: 12% and DPPC: 42%. The optimal liposome formulation had an average diameter of 127.5 nm, a phase-transition temperature of 11.43 °C, a ζ-potential of -7.24 mV, fluidity (1/P)(TMA-DPH)((¬)) value of 2.87 and an encapsulation efficiency of 20.24%. The experimental results of characterization of optimal liposome formulation were in good agreement with those predicted by the mixture design technique.

  10. Recent Advances and Perspectives in Liposomes for Cutaneous Drug Delivery.

    Science.gov (United States)

    Carita, Amanda C; Eloy, Josimar O; Chorilli, Marlus; Lee, Robert J; Leonardi, Gislaine Ricci

    2018-02-13

    The cutaneous route is attractive for the delivery of drugs in the treatment of a wide variety of diseases. However the stratum corneum (SC) is an effective barrier that hampers skin penetration. Within this context, liposomes emerge as a potential carrier for improving topical delivery of therapeutic agents. In this review, we aimed to discuss key aspects for the topical delivery by drug-loaded liposomes. Phospholipid type and phase transition temperature have been shown to affect liposomal topical delivery. The effect of surface charge is subject to considerable variation depending on drug and composition. In addition, modified vesicles with the presence of components for permeation enhancement, such as surfactants and solvents, have been shown to have a considerable effect. These liposomes include: Transfersomes, Niosomes, Ethosomes, Transethosomes, Invasomes, coated liposomes, penetration enhancer containing vesicles (PEVs), fatty acids vesicles, Archaeosomes and Marinosomes. Furthermore, adding polymeric coating onto liposome surface could influence cutaneous delivery. Mechanisms of delivery include intact vesicular skin penetration, free drug diffusion, permeation enhancement, vesicle adsorption to and/or fusion with the SC, trans-appendageal penetration, among others. Finally, several skin conditions, including acne, melasma, skin aging, fungal infections and skin cancer, have benefited from liposomal topical delivery of drugs, with promising in vitro and in vivo results. However, despite the existence of some clinical trials, more studies are needed to be conducted in order to explore the potential of liposomes in the dermatological field. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  11. Radiolabeling, biodistribution and tumor imaging of stealth liposomes containing methotrexate

    International Nuclear Information System (INIS)

    Subramanian, N; Arulsudar, N; Chuttani, K; Mishra, P; Sharma, R.K; Murthy, R.S.R

    2003-01-01

    To study the utility of sterically stabilized liposomes (stealth liposomes) in tumor scintigraphy by studying its biodistribution and accumulation in target tissue after radiolabeling with Technetium-99m (99mTC). Conventional and Stealth liposomes were prepared by lipid film hydration method using methotrexate as model anticancer drug. Radiolabeling of the liposomes was carried out by direct labeling using reduced 99mTc. Experimental conditions for maximum labeling yield were optimized. The stability studies were carried out to check binding strength of the radiolabeled complexes. The blood kinetic study was carried out in rabbits after giving the labeled complex by intravenous administration through ear vein. The biodistribution studies were carried out in the Ehrlich ascites tumor (EAT) bearing mice after intravenous administration through tail vein, showed prolonged circulation in blood and significant increase in the accumulation in tumor for the sterically stabilized liposomes compared to the conventional liposomes. The gamma scintigraphic image shows the distribution of the stealth liposomes in liver, spleen, kidney and tumor. The study gives precise idea about the use of stealth liposomes in tumor scintigraphy and organ distribution studies (Au)

  12. Programmable fusion of liposomes mediated by lipidated PNA

    DEFF Research Database (Denmark)

    Rabe, A; Löffler, P M G; Ries, O

    2017-01-01

    We recently reported a DNA-programmed fusion cascade enabling the use of liposomes as nanoreactors for compartmentalized chemical reactions. This communication reports an alternative and robust strategy based on lipidated peptide nucleic acids (LiPs). LiPs enabled fusion of liposomes with remarka...... with remarkable 31% efficiency at 50 °C with low leakage (5%)....

  13. Presence of electrostatically adsorbed polysaccharides improves spray drying of liposomes.

    Science.gov (United States)

    Karadag, Ayse; Özçelik, Beraat; Sramek, Martin; Gibis, Monika; Kohlus, Reinhard; Weiss, Jochen

    2013-02-01

    Spray drying of liposomes with conventional wall materials such as maltodextrins often yields nonfunctional powders, that is, liposomes break down during drying and rehydration. Electrostatically coating the surface of liposomes with a charged polymer prior to spray drying may help solve this problem. Anionic lecithin liposomes (approximately 400 nm) were coated with lower (approximately 500 kDa, LMW-C) or higher (approximately 900 kDa, HMW-C) molecular weight cationic chitosan using the layer-by-layer depositing method. Low (DE20, LMW-MD) or high molecular weight (DE2, HMW-MD) maltodextrin was added as wall material to facilitate spray drying. If surfaces of liposomes (1%) were completely covered with chitosan (0.4%), no bridging or depletion flocculation would occur, and mean particle diameters would be approximately 500 nm. If maltodextrins (20%) were added to uncoated liposomes, extensive liposomal breakdown would occur making the system unsuitable for spray drying. No such aggregation or breakdown was observed when maltodextrin was added to chitosan-coated liposomes. Size changed little or even decreased slightly depending on the molecular weight of maltodextrin added. Scanning electron microscopy images of powders containing chitosan-coated liposomes revealed that their morphologies depended on the type of maltodextrin added. Powders prepared with LMW-MD contained mostly spherical particles while HMW-MD powders contained particles with concavities and dents. Upon redispersion, coated liposomes yielded back dispersions with particle size distributions similar to the original ones, except for LMW-C coated samples that had been spray dried with HMW-MD which yielded aggregates (approximately 30 μm). Results show that coating of liposomes with an absorbing polymer allows them to be spray dried with conventional maltodextrin wall materials. Liposomes have attracted considerable attention in the food and agricultural, biomedical industries for the delivery of

  14. Liposomal Formulations in Clinical Use: An Updated Review

    Directory of Open Access Journals (Sweden)

    Upendra Bulbake

    2017-03-01

    Full Text Available Liposomes are the first nano drug delivery systems that have been successfully translated into real-time clinical applications. These closed bilayer phospholipid vesicles have witnessed many technical advances in recent years since their first development in 1965. Delivery of therapeutics by liposomes alters their biodistribution profile, which further enhances the therapeutic index of various drugs. Extensive research is being carried out using these nano drug delivery systems in diverse areas including the delivery of anti-cancer, anti-fungal, anti-inflammatory drugs and therapeutic genes. The significant contribution of liposomes as drug delivery systems in the healthcare sector is known by many clinical products, e.g., Doxil®, Ambisome®, DepoDur™, etc. This review provides a detailed update on liposomal technologies e.g., DepoFoam™ Technology, Stealth technology, etc., the formulation aspects of clinically used products and ongoing clinical trials on liposomes.

  15. The Treatment of Breast Cancer Using Liposome Technology

    Directory of Open Access Journals (Sweden)

    Sarah Brown

    2012-01-01

    Full Text Available Liposome-based chemotherapeutics used in the treatment of breast cancer can in principle enhance the therapeutic index of otherwise unencapsulated anticancer drugs. This is partially attributed to the fact that encapsulation of cytotoxic agents within liposomes allows for increased concentrations of the drug to be delivered to the tumor site. In addition, the presence of the phospholipid bilayer prevents the encapsulated active form of the drug from being broken down in the body prior to reaching tumor tissue and also serves to minimize exposure of the drug to healthy sensitive tissue. While clinically approved liposome-based chemotherapeutics such as Doxil have proven to be quite effective in the treatment of breast cancer, significant challenges remain involving poor drug transfer between the liposome and cancerous cells. In this review, we discuss the recent advancements made in the development of liposome-based chemotherapeutics with respect to improved drug transfer for use in breast cancer therapy.

  16. Interactions of a Photochromic Spiropyran with Liposome Model Membranes

    KAUST Repository

    Jonsson, Fabian

    2013-02-19

    The interactions between anionic or zwitterionic liposomes and a water-soluble, DNA-binding photochromic spiropyran are studied using UV/vis absorption and linear dichroism (LD) spectroscopy. The spectral characteristics as well as the kinetics of the thermal isomerization process in the absence and presence of the two different liposome types provide information about the environment and whether or not the spiropyran resides in the liposome membrane. By measuring LD on liposomes deformed and aligned by shear flow, further insight is obtained about interaction and binding geometry of the spiropyran at the lipid membranes. We show that the membrane interactions differ between the two types of liposomes used as well as the isomeric forms of the spiropyran photoswitch. © 2013 American Chemical Society.

  17. Recent advances on liposomal nanoparticles: synthesis, characterization and biomedical applications.

    Science.gov (United States)

    Panahi, Yunes; Farshbaf, Masoud; Mohammadhosseini, Majid; Mirahadi, Mozhdeh; Khalilov, Rovshan; Saghfi, Siamak; Akbarzadeh, Abolfazl

    2017-06-01

    Liposome is a new nanostructure for the encapsulation and delivery of bioactive agents. There are a lot of bioactive materials that could be incorporated into liposomes including cosmetics, food ingredients, and pharmaceuticals. Liposomes possess particular properties such as biocompatibility, biodegradability; accompanied by their nanosize they have potential applications in nanomedicine, cosmetics, and food industry. Nanoliposome technology offers thrilling chances for food technologists in fields including encapsulation and controlled release of food ingredients, also improved bioavailability and stability of sensitive materials. Amid numerous brilliant new drug and gene delivery systems, liposomes provide an advanced technology to carry active molecules to the specific site of action, and now days, various formulations are in clinical use. In this paper, we provide review of the main physicochemical properties of liposomes, current methods of the manufacturing and introduce some of their usage in food nanotechnology as carrier vehicles of nutrients, enzymes, and food antimicrobials and their applications as drug carriers and gene delivery agents in biomedicine.

  18. Ultrasound triggered drug delivery with liposomal nested microbubbles.

    Science.gov (United States)

    Wallace, N; Wrenn, S P

    2015-12-01

    When ultrasound contrast agent microbubbles are nested within a liposome, damage to the liposome membrane caused by both stable and inertial cavitation of the microbubble allows for release of the aqueous core of the liposome. Triggered release was not accomplished unless microbubbles were present within the liposome. Leakage was tested using fluorescence assays developed specifically for this drug delivery vehicle and qualitative measurements using an optical microscope. These studies were done using a 1 MHz focused ultrasound transducer while varying parameters including peak negative ultrasound pressure, average liposome diameter, and microbubble concentration. Two regimes exist for membrane disruption caused by cavitating microbubbles. A faster release rate, as well as permanent membrane damage are seen for samples exposed to high pressure (2.1-3.7 MPa). A slower release rate and dilation/temporary poration are characteristic of stable cavitation for low pressure studies (0.54-1.7 MPa). Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Multimodal targeted high relaxivity thermosensitive liposome for in vivo imaging

    Science.gov (United States)

    Kuijten, Maayke M. P.; Hannah Degeling, M.; Chen, John W.; Wojtkiewicz, Gregory; Waterman, Peter; Weissleder, Ralph; Azzi, Jamil; Nicolay, Klaas; Tannous, Bakhos A.

    2015-11-01

    Liposomes are spherical, self-closed structures formed by lipid bilayers that can encapsulate drugs and/or imaging agents in their hydrophilic core or within their membrane moiety, making them suitable delivery vehicles. We have synthesized a new liposome containing gadolinium-DOTA lipid bilayer, as a targeting multimodal molecular imaging agent for magnetic resonance and optical imaging. We showed that this liposome has a much higher molar relaxivities r1 and r2 compared to a more conventional liposome containing gadolinium-DTPA-BSA lipid. By incorporating both gadolinium and rhodamine in the lipid bilayer as well as biotin on its surface, we used this agent for multimodal imaging and targeting of tumors through the strong biotin-streptavidin interaction. Since this new liposome is thermosensitive, it can be used for ultrasound-mediated drug delivery at specific sites, such as tumors, and can be guided by magnetic resonance imaging.

  20. Preparation of venlafaxine hydrochloride sustained-release tablets

    Directory of Open Access Journals (Sweden)

    GUO Lingling

    2013-08-01

    Full Text Available To prepare venlafxine hydrochloride sustained-release tablets.Hydroxypropylmethyl cellulose(HPMC and methyl cellulose(MC were used as main materials to prepare sustained-release tablets of velafaxine hydrochloride and the influence of important factors on in vitro release curves of venlafaxine hydrochloride sustained-release tablets was investigated.Results:The optimal prescription included 100 mg HPMC,25 mg MC,and 2.5% glidant in one tablet prepared with 30kN.The tablets were prepared with the method of wet granulation by NO.16 mesh sieve.The tablets exhibited good sustained-release property in phosphate buffered solution (pH=6.8.The as-prepared venlafxine hydrochloride sustained-release tablets have good sustained-release property.

  1. Liposomal nanoparticles encapsulating iloprost exhibit enhanced vasodilation in pulmonary arteries

    Directory of Open Access Journals (Sweden)

    Jain PP

    2014-07-01

    Full Text Available Pritesh P Jain,1 Regina Leber,1,2 Chandran Nagaraj,1 Gerd Leitinger,3 Bernhard Lehofer,4 Horst Olschewski,1,5 Andrea Olschewski,1,6 Ruth Prassl,1,4 Leigh M Marsh11Ludwig Boltzmann Institute for Lung Vascular Research, 2Biophysics Division, Institute of Molecular Biosciences, University of Graz, 3Research Unit Electron Microscopic Techniques, Institute of Cell Biology, Histology, and Embryology, 4Institute of Biophysics, 5Division of Pulmonology, Department of Internal Medicine, 6Department of Anesthesiology and Intensive Care Medicine, Medical University of Graz, Graz, AustriaAbstract: Prostacyclin analogues are standard therapeutic options for vasoconstrictive diseases, including pulmonary hypertension and Raynaud’s phenomenon. Although effective, these treatment strategies are expensive and have several side effects. To improve drug efficiency, we tested liposomal nanoparticles as carrier systems. In this study, we synthesized liposomal nanoparticles tailored for the prostacyclin analogue iloprost and evaluated their pharmacologic efficacy on mouse intrapulmonary arteries, using a wire myograph. The use of cationic lipids, stearylamine, or 1,2-di-(9Z-octadecenoyl-3-trimethylammonium-propane (DOTAP in liposomes promoted iloprost encapsulation to at least 50%. The addition of cholesterol modestly reduced iloprost encapsulation. The liposomal nanoparticle formulations were tested for toxicity and pharmacologic efficacy in vivo and ex vivo, respectively. The liposomes did not affect the viability of human pulmonary artery smooth muscle cells. Compared with an equivalent concentration of free iloprost, four out of the six polymer-coated liposomal formulations exhibited significantly enhanced vasodilation of mouse pulmonary arteries. Iloprost that was encapsulated in liposomes containing the polymer polyethylene glycol exhibited concentration-dependent relaxation of arteries. Strikingly, half the concentration of iloprost in liposomes elicited

  2. Ultrasound, liposomes, and drug delivery: principles for using ultrasound to control the release of drugs from liposomes.

    Science.gov (United States)

    Schroeder, Avi; Kost, Joseph; Barenholz, Yechezkel

    2009-11-01

    Ultrasound is used in many medical applications, such as imaging, blood flow analysis, dentistry, liposuction, tumor and fibroid ablation, and kidney stone disruption. In the past, low frequency ultrasound (LFUS) was the main method to downsize multilamellar (micron range) vesicles into small (nano scale) unilamellar vesicles. Recently, the ability of ultrasound to induce localized and controlled drug release from liposomes, utilizing thermal and/or mechanical effects, has been shown. This review, deals with the interaction of ultrasound with liposomes, focusing mainly on the mechanical mechanism of drug release from liposomes using LFUS. The effects of liposome lipid composition and physicochemical properties, on one hand, and of LFUS parameters, on the other, on liposomal drug release, are addressed. Acoustic cavitation, in which gas bubbles oscillate and collapse in the medium, thereby introducing intense mechanical strains, increases release substantially. We suggest that the mechanism of release may involve formation and collapse of small gas nuclei in the hydrophobic region of the lipid bilayer during exposure to LFUS, thereby inducing the formation of transient pores through which drugs are released. Introducing PEG-lipopolymers to the liposome bilayer enhances responsivity to LFUS, most likely due to absorption of ultrasonic energy by the highly hydrated PEG headgroups. The presence of amphiphiles, such as phospholipids with unsaturated acyl chains, which destabilize the lipid bilayer, also increases liposome susceptibility to LFUS. Application of these principles to design highly LFUS-responsive liposomes is discussed.

  3. Formulation and evaluation of tramadol hydrochloride rectal suppositories

    OpenAIRE

    Saleem M; Taher M; Sanaullah S; Najmuddin M; Ali Javed; Humaira S; Roshan S

    2008-01-01

    Rectal suppositories of tramadol hydrochloride were prepared using different bases and polymers like PEG, cocoa butter, agar and the effect of different additives on in vitro release of tramadol hydrochloride was studied. The agar-based suppositories were non-disintegrating/non-dissolving, whereas PEGs were disintegrating/dissolving and cocoa butter were melting suppositories. All the prepared suppositories were evaluated for various physical parameters like weight variation, drug content a...

  4. Clearance and localization of intravitreal liposomes in the aphakic vitrectomized eye

    International Nuclear Information System (INIS)

    Stern, W.H.; Heath, T.D.; Lewis, G.P.; Guerin, C.J.; Erickson, P.A.; Lopez, N.G.; Hong, K.L.

    1987-01-01

    The authors have examined the fate of intravitreally injected liposomes in the aphakic, vitrectomized eye of the rabbit. Liposomes labelled with 125 [I]-p-hydroxybenzimidylphosphatidylethanolamine were eliminated rapidly from the intraocular fluid. Nonetheless, a significant fraction of these liposomes were found to bind to various ocular tissues including the retina, iris, sclera, and cornea. Ultrastructural studies with gold colloid-loaded liposomes revealed that retinal bound liposomes were attached to the inner limiting lamina but did not penetrate to the internal cells of the retina. Epiretinal cells bound and internalized gold colloid-loaded liposomes suggesting that these cells may be very sensitive to liposome mediated drug delivery

  5. Modification of liposomal concentration in liposome/adenoviral complexes allows significant protection of adenoviral vectors from neutralising antibody, in vitro.

    Science.gov (United States)

    Steel, Jason C; Cavanagh, Heather M A; Burton, Mark A; Dingwall, Daniel J; Kalle, Wouter H J

    2005-06-01

    Adenoviral vectors have been commonly used in gene therapy protocols, however the success of their use is often limited by the induction of host immunity to the vector. Following exposure to the adenoviral vector, adenoviral-specific neutralising antibodies are produced which limits further administration. This study examines the efficacy of complexing liposomes to adenovirus for the protection of the adenovirus from neutralising antibodies in an in vitro setting. Dimethyldioctadecylammonium bromide (DDAB)-dioleoyl-l-phosphatidylethanolamine (DOPE) liposomes were bound at varying concentrations to adenovirus to form AL complexes and tested these complexes' ability to prevent adenoviral neutralisation. It is shown that by increasing the concentration of liposomes in the adenoviral-liposome (AL) complexes we can increase the level of immuno-shielding afforded the adenovirus. It is also shown that the increase in liposomal concentration may lead to drawbacks such as increased cytotoxicity and reductions in expression levels.

  6. Development of Liposomal Bubbles with Perfluoropropane Gas as Gene Delivery Carriers

    Science.gov (United States)

    Maruyama, Kazuo; Suzuki, Ryo; Sawamura, Kaori; Takizawa, Tomoko; Utoguchi, Naoki; Negishi, Yoichi

    2007-05-01

    Liposomes have some advantages as drug, antigen and gene delivery carriers. Their size can be easily controlled and they can be modified to add a targeting function. Based on liposome technology, we developed novel liposomal bubbles (Bubble liposomes) containing the ultrasound imaging gas, perfluoropropane. We assessed the feasibility of Bubble liposomes as carriers for gene delivery after cavitation induced by ultrasound. At first, we investigated their ability to deliver genes with Bubble liposomes and ultrasound to various types of cells such as mouse sarcoma cells, mouse melanoma cells, human T cell line and human umbilical vein endothelial cells. The results showed that the Bubble liposomes could deliver plasmid DNA to many cell types without cytotoxicity. In addition, we found that Bubble liposomes could effectively deliver plasmid DNA into mouse femoral artery in vivo. The gene transduction with Bubble liposomes was more effectively than conventional lipofection. We conclude that Bubble liposomes are unique and efficient gene delivery carriers in vitro and in vivo.

  7. Liposomal Drug Delivery of Anticancer Agents

    DEFF Research Database (Denmark)

    Pedersen, Palle Jacob

    and retention (EPR) effect. The liposomes consists of sPLA2 IIA sensitive phospholipids having anticancer drugs covalently attached to the sn-2 position of the glycerol backbone in the phospholipids, hence drug leakage is avoided from the carrier system. Various known anticancer agents, like chlorambucil, all......) based strategy using a limited number of reaction types. Upon coupling of unsaturated building blocks ring closing metathesis cascades were used to “reprogram” the molecular scaffold and highly diverse structures were obtained. In total 20 novel compounds with a broad structural diversity were prepared...

  8. Silica-Coated Liposomes for Insulin Delivery

    Directory of Open Access Journals (Sweden)

    Neelam Dwivedi

    2010-01-01

    Full Text Available Liposomes coated with silica were explored as protein delivery vehicles for their enhanced stability and improved encapsulation efficiency. Insulin was encapsulated within the fluidic phosphatidylcholine lipid vesicles by thin film hydration at pH 2.5, and layer of silica was formed above lipid bilayer by acid catalysis. The presence of silica coating and encapsulated insulin was identified using confocal and electron microscopy. The native state of insulin present in the formulation was evident from Confocal Micro-Raman spectroscopy. Silica coat enhances the stability of insulin-loaded delivery vehicles. In vivo study shows that these silica coated formulations were biologically active in reducing glucose levels.

  9. Delivery of aerosolized drugs encapsulated in liposomes

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yung-Sung; Lyons, C.R. [Univ. of New Mexico, Albuquerque, NM (United States); Schmid, M.H.

    1995-12-01

    Mycobacterium tuberculosis (Mtb) is an infectious disease that resides in the human lung. Due to the difficulty in completely killing off the disease in infected individuals, Mtb has developed drug-resistant forms and is on the rise in the human population. Therefore, ITRI and the University of New Mexico are collaborating to explore the treatment of Mtb by an aerosolized drug delivered directly to the lungs. In conclusion, it is feasible to obtain an appropriate size and concentration of the liposomes before and after aerosolization.

  10. Delivery of aerosolized drugs encapsulated in liposomes

    International Nuclear Information System (INIS)

    Cheng, Yung-Sung; Lyons, C.R.; Schmid, M.H.

    1995-01-01

    Mycobacterium tuberculosis (Mtb) is an infectious disease that resides in the human lung. Due to the difficulty in completely killing off the disease in infected individuals, Mtb has developed drug-resistant forms and is on the rise in the human population. Therefore, ITRI and the University of New Mexico are collaborating to explore the treatment of Mtb by an aerosolized drug delivered directly to the lungs. In conclusion, it is feasible to obtain an appropriate size and concentration of the liposomes before and after aerosolization

  11. Simultaneous Estimation of Gemcitabine Hydrochloride and Capecitabine Hydrochloride in Combined Tablet Dosage Form by RP-HPLC Method

    Directory of Open Access Journals (Sweden)

    V. Rajesh

    2011-01-01

    Full Text Available A new reverse phase high performance liquid chromatography (RP-HPLC method has been developed for the simultaneous estimation of gemcitabine hydrochloride and capecitabine hydrochloride in combined tablet dosage form. An inertsil ODS-3 C-18 column having dimensions of 250×4.6 mm and particle size of 5 µm, with mobile phase containing a mixture of acetonitrile : water : triethyelamine in the ratio of (70 : 28 : 2v/v was used. The pH of mobile phase was adjusted to 4.0 with ortho-phosphoric acid. The flow rate was 1 mL/min and the column effluents were monitored at 260 nm. The retention time for gemcitabine hydrochloride and capecitabine hydrochloride was found to be 2.76 and 2.3 min respectively. The proposed method was validated in terms of linearity, accuracy, precision, limit of detection, limit of quantitation and robustness. The method was found to be linear in the range of 10-50 µg/mL and 4-24 µg/mL for gemcitabine hydrochloride and capecitabine hydrochloride, with regression coefficient r = 0.999 and r = 0.999, respectively.

  12. Effect of Lipid Composition on In Vitro Release and Skin Deposition of Curcumin Encapsulated Liposomes

    Directory of Open Access Journals (Sweden)

    Geethi Pamunuwa

    2016-01-01

    Full Text Available Liposomal encapsulation improves numerous physiochemical and biological properties of curcumin. The aim of this work was to impart slow release and skin delivery of curcumin via liposomal encapsulation. Liposomes were made using egg yolk phosphatidylcholine as the staple lipid while incorporating polysorbate 80 and stearylamine to prepare hybrid liposomes and positively charged liposomes, respectively. Negatively charged liposomes exhibited the highest encapsulation efficiencies (87.8±4.3% and loading capacities (3.4±0.2%. The sizes of all formulations were about 250 nm, while stearylamine increased the polydispersity index. Positively charged liposomes showed lower degradation temperatures than negatively charged liposomes by 10–15°C, attributable to the presence of stearylamine. The melting temperatures of positively charged liposomes (40–50°C were much higher than those of negatively charged liposomes (14-15°C, which may have affected release and skin deposition behavior of liposomes. The positively charged liposomes exhibited the slowest release of curcumin in phosphate buffered saline (pH 6.8 and the release profiles of all liposomal formulations conformed to the Gompertz model. The negatively charged liposomes facilitated the highest skin deposition of curcumin as revealed by studies conducted using excised pig ear skin. Concisely, positively and negatively charged liposomes were optimal for slow release and skin deposition of curcumin, respectively.

  13. Liposomal encapsulated Zn-DTPA for removing intracellular 169Yb

    International Nuclear Information System (INIS)

    Blank, M.L.; Cress, E.A.; Byrd, B.L.; Washburn, L.C.; Snyder, F.

    1980-01-01

    Multilamellar liposomes possessing neutral positive or negative charges were tested for their capacity to encapsulate sodium ethylenediaminetetraacetate (EDTA) and for their selectivity in depositing in specific tissues after being injected into rats. Negative-charged liposomes had the greatest trapping efficiency over a wide range of lipid-to-aqueous phase ratios. In contrast, except for lung, liposomal charge had no significant effect on the tissue distribution of encapsulated EDTA; liver and spleen exhibited the highest uptake with all preparations. The proportion of encapsulated EDTA taken up by the liver decreased as the amount of injected liposomes was increased. Free zinc diethylenetriaminepentaacetate (Zn-DTPA) and multilamellar liposomes containing entrapped Zn-DTPA were administered to rats that had been injected with 169 Yb-citrate 24 hr earlier. At doses of 14 mg Zn-DTPA per kg body weight, both free Zn-DPTA and the liposomal-bound Zn-DTPA caused increased removal of 169 Yb from the animals. However, treatment with the liposomal Zn-DTPA caused significantly more of the 169 Yb to be removed than did the free Zn-DTPA treatment by itself. Our data indicate that lipophilic forms of chelators can effectively increase the removal rates of heavy metal contamination in tissues. (author)

  14. Heparin octasaccharide decoy liposomes inhibit replication of multiple viruses

    Science.gov (United States)

    Hendricks, Gabriel L.; Velazquez, Lourdes; Pham, Serena; Qaisar, Natasha; Delaney, James C.; Viswanathan, Karthik; Albers, Leila; Comolli, James C.; Shriver, Zachary; Knipe, David M.; Kurt-Jones, Evelyn A.; Fygenson, Deborah K.; Trevejo, Jose M.

    2016-01-01

    Heparan sulfate (HS) is a ubiquitous glycosaminoglycan that serves as a cellular attachment site for a number of significant human pathogens, including respiratory syncytial virus (RSV), human parainfluenza virus 3 (hPIV3), and herpes simplex virus (HSV). Decoy receptors can target pathogens by binding to the receptor pocket on viral attachment proteins, acting as ‘molecular sinks’ and preventing the pathogen from binding to susceptible host cells. Decoy receptors functionalized with HS could bind to pathogens and prevent infection, so we generated decoy liposomes displaying HS-octasaccharide (HS-octa). These decoy liposomes significantly inhibited RSV, hPIV3, and HSV infectivity in vitro to a greater degree than the original HS-octa building block. The degree of inhibition correlated with the density of HS-octa displayed on the liposome surface. Decoy liposomes with HS-octa inhibited infection of viruses to a greater extent than either full-length heparin or HS-octa alone. Decoy liposomes were effective when added prior to infection or following the initial infection of cells in vitro. By targeting the well-conserved receptor-binding sites of HS-binding viruses, decoy liposomes functionalized with HS-octa are a promising therapeutic antiviral agent and illustrate the utility of the liposome delivery platform. PMID:25637710

  15. Formulation and Evaluation of Rifampicin Liposomes for Buccal Drug Delivery.

    Science.gov (United States)

    Lankalapalli, Srinivas; Tenneti, V S Vinai Kumar

    2016-01-01

    Drug delivery through liposomes offers several advantages, but still challenging to the researchers for the use of liposomes as carriers in drug delivery due to their poor physical stability, unpredictable drug encapsulation and systemic availability of the loaded drug. The present investigation was planned with an objective to prepare Rifampicin loaded liposomes by using response surface methodology of statistical 32 factorial design and further to formulate them into pastilles for deliver through buccal route thereby to enhance systemic absorption. Rifampicin liposomes were prepared by using different ratios of soya lecithin and cholesterol by solvent Injection method. These liposomes were characterized by using optical microscopy, Scanning Electron Microscopy (SEM) and evaluated for particle size, entrapment efficiency (EE), in vitro and ex vivo drug release. Main effects and interaction terms of the formulation variables were evaluated quantitatively using a mathematical statistical model approach showing that both independent variables have significant (P value value: 0.0273), percentage entrapment efficiency (P value: 0.0096), percentage drug release through dialysis membrane (P value: 0.0047) and percentage drug release through porcine buccal membrane (P value: 0.0019). The statistical factorial design of liposomal formulations fulfilled all the requirements of the target set and exhibited suitable values for the selected test parameters. Pastilles were prepared for liposomes using glycerol gelatin base and were found to be soft, smooth with uniform drug content and drug release.

  16. Multimodality imaging demonstrates trafficking of liposomes preferentially to ischemic myocardium

    International Nuclear Information System (INIS)

    Lipinski, Michael J.; Albelda, M. Teresa; Frias, Juan C.; Anderson, Stasia A.; Luger, Dror; Westman, Peter C.; Escarcega, Ricardo O.; Hellinga, David G.; Waksman, Ron; Arai, Andrew E.; Epstein, Stephen E.

    2016-01-01

    Introduction: Nanoparticles may serve as a promising means to deliver novel therapeutics to the myocardium following myocardial infarction. We sought to determine whether lipid-based liposomal nanoparticles can be shown through different imaging modalities to specifically target injured myocardium following intravenous injection in an ischemia–reperfusion murine myocardial infarction model. Methods: Mice underwent ischemia–reperfusion surgery and then either received tail-vein injection with gadolinium- and fluorescent-labeled liposomes or no injection (control). The hearts were harvested 24 h later and underwent T1 and T2-weighted ex vivo imaging using a 7 Tesla Bruker magnet. The hearts were then sectioned for immunohistochemistry and optical fluorescent imaging. Results: The mean size of the liposomes was 100 nm. T1-weighted signal intensity was significantly increased in the ischemic vs. the non-ischemic myocardium for mice that received liposomes compared with control. Optical imaging demonstrated significant fluorescence within the infarct area for the liposome group compared with control (163 ± 31% vs. 13 ± 14%, p = 0.001) and fluorescent microscopy confirmed the presence of liposomes within the ischemic myocardium. Conclusions: Liposomes traffic to the heart and preferentially home to regions of myocardial injury, enabling improved diagnosis of myocardial injury and could serve as a vehicle for drug delivery.

  17. Multimodality imaging demonstrates trafficking of liposomes preferentially to ischemic myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Lipinski, Michael J., E-mail: mjlipinski12@gmail.com [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States); Albelda, M. Teresa [GIBI2" 3" 0, Grupo de Investigación Biomédica en Imagen, IIS La Fe, Valencia (Spain); Frias, Juan C. [Departamento de Ciencias Biomédicas, Universidad CEU Cardenal Herrera, Valencia (Spain); Anderson, Stasia A. [Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD (United States); Luger, Dror; Westman, Peter C.; Escarcega, Ricardo O.; Hellinga, David G.; Waksman, Ron [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States); Arai, Andrew E. [Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD (United States); Epstein, Stephen E. [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States)

    2016-03-15

    Introduction: Nanoparticles may serve as a promising means to deliver novel therapeutics to the myocardium following myocardial infarction. We sought to determine whether lipid-based liposomal nanoparticles can be shown through different imaging modalities to specifically target injured myocardium following intravenous injection in an ischemia–reperfusion murine myocardial infarction model. Methods: Mice underwent ischemia–reperfusion surgery and then either received tail-vein injection with gadolinium- and fluorescent-labeled liposomes or no injection (control). The hearts were harvested 24 h later and underwent T1 and T2-weighted ex vivo imaging using a 7 Tesla Bruker magnet. The hearts were then sectioned for immunohistochemistry and optical fluorescent imaging. Results: The mean size of the liposomes was 100 nm. T1-weighted signal intensity was significantly increased in the ischemic vs. the non-ischemic myocardium for mice that received liposomes compared with control. Optical imaging demonstrated significant fluorescence within the infarct area for the liposome group compared with control (163 ± 31% vs. 13 ± 14%, p = 0.001) and fluorescent microscopy confirmed the presence of liposomes within the ischemic myocardium. Conclusions: Liposomes traffic to the heart and preferentially home to regions of myocardial injury, enabling improved diagnosis of myocardial injury and could serve as a vehicle for drug delivery.

  18. Liposomes to target peripheral neurons and Schwann cells.

    Directory of Open Access Journals (Sweden)

    Sooyeon Lee

    Full Text Available While a wealth of literature for tissue-specific liposomes is emerging, optimal formulations to target the cells of the peripheral nervous system (PNS are lacking. In this study, we asked whether a novel formulation of phospholipid-based liposomes could be optimized for preferential uptake by microvascular endothelia, peripheral neurons and Schwann cells. Here, we report a unique formulation consisting of a phospholipid, a polymer surfactant and cholesterol that result in enhanced uptake by targeted cells. Using fluorescently labeled liposomes, we followed particle internalization and trafficking through a distinct route from dextran and escape from degradative compartments, such as lysosomes. In cultures of non-myelinating Schwann cells, liposomes associate with the lipid raft marker Cholera toxin, and their internalization is inhibited by disruption of lipid rafts or actin polymerization. In contrast, pharmacological inhibition of clathrin-mediated endocytosis does not significantly impact liposome entry. To evaluate the efficacy of liposome targeting in tissues, we utilized myelinating explant cultures of dorsal root ganglia and isolated diaphragm preparations, both of which contain peripheral neurons and myelinating Schwann cells. In these models, we detected preferential liposome uptake into neurons and glial cells in comparison to surrounding muscle tissue. Furthermore, in vivo liposome administration by intramuscular or intravenous injection confirmed that the particles were delivered to myelinated peripheral nerves. Within the CNS, we detected the liposomes in choroid epithelium, but not in myelinated white matter regions or in brain parenchyma. The described nanoparticles represent a novel neurophilic delivery vehicle for targeting small therapeutic compounds, biological molecules, or imaging reagents into peripheral neurons and Schwann cells, and provide a major advancement toward developing effective therapies for peripheral

  19. Giant liposomes as delivery system for ecophysiological studies in copepods.

    Science.gov (United States)

    Buttino, Isabella; De Rosa, Giuseppe; Carotenuto, Ylenia; Ianora, Adrianna; Fontana, Angelo; Quaglia, Fabiana; La Rotonda, Maria Immacolata; Miralto, Antonio

    2006-03-01

    Giant liposomes are proposed as a potential delivery system in marine copepods, the dominant constituent of the zooplankton. Liposomes were prepared in the same size range as the food ingested by copepods (mean diameter of about 7 microm). The encapsulation of a hydrophilic and high molecular mass fluorescent compound, fluorescein isothiocyanate-dextran (FitcDx), within the liposomes provided a means of verifying copepod ingestion when viewed with the confocal laser-scanning microscope. Females of the calanoid copepod Temora stylifera were fed with FitcDx-encapsulated liposomes alone or mixed with the dinoflagellate alga Prorocentrum minimum. Control copepods were incubated with the P. minimum diet alone. Egg production rates, percentage egg-hatching success and number of faecal pellets produced were evaluated after 24 h and 48 h of feeding. Epifluorescence of copepod gut and faecal pellets indicated that the liposomes were actively ingested by T. stylifera in both experimental food conditions, with or without the dinoflagellate diet. Ingestion rates calculated using 3H-labelled liposomes indicated that females ingested more liposomes when P. minimum was added to the solution (16% vs 7.6% of uptake). When liposomes were supplied together with the algal diet, egg production rate, egg-hatching success and faecal pellet production were as high as those observed for the control diet. By contrary, egg production and hatching success were very low with a diet of liposomes alone and faecal pellet production was similar to that recorded in starved females. This results suggest that liposomes alone did not add any nutritive value to the diet, making them a good candidate as inert carriers to study the nutrient requirements or biological activity of different compounds. In particular, such liposomes are proposed as carriers for diatom-derived polyunsaturated aldehydes, which are known to impair copepod embryo viability. Other potential applications of liposomes as a delivery

  20. Solubility and bioavailability improvement of pazopanib hydrochloride.

    Science.gov (United States)

    Herbrink, Maikel; Groenland, Stefanie L; Huitema, Alwin D R; Schellens, Jan H M; Beijnen, Jos H; Steeghs, Neeltje; Nuijen, Bastiaan

    2018-06-10

    The anti-cancer drug pazopanib hydrochloride (PZH) has a very low aqueous solubility and a variable oral bioavailability. A new pharmaceutical formulation with an improved solubility may enhance the bioavailability and reduce the variability. A broad selection of polymer excipients was tested for their compatibility and solubilizing properties by conventional microscopic, thermal and spectrometric techniques. A wet milling and mixing technique was used to produce homogenous powder mixtures. The dissolution properties of the formulation were tested by a pH-switch dissolution model. The final formulation was tested in vivo in cancer patient following a dose escalation design. Of the tested mixture formulations, the one containing the co-block polymer Soluplus® in a 8:1 ratio with PZH performed best in terms of in vitro dissolution properties. The in vivo results indicated that 300 mg of the developed formulation yields similar exposure and a lower variability (379 μg/mL∗h (36.7% CV)) than previously reported values for the standard PZH formulation (Votrient®) at the approved dose of 800 mg. Furthermore, the expected plasma-C through levels (27.2 μg/mL) exceeds the defined therapeutic efficacy threshold of 20 μg/mL. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Superresolution and Fluorescence Dynamics Evidence Reveal That Intact Liposomes Do Not Cross the Human Skin Barrier

    DEFF Research Database (Denmark)

    Dreier, Jes; Sørensen, Jens A; Brewer, Jonathan R

    2016-01-01

    In this study we use the combination of super resolution optical microscopy and raster image correlation spectroscopy (RICS) to study the mechanism of action of liposomes as transdermal drug delivery systems in human skin. Two different compositions of liposomes were applied to newly excised human...... skin, a POPC liposome and a more flexible liposome containing the surfactant sodium cholate. Stimulated emission depletion microscopy (STED) images of intact skin and cryo-sections of skin treated with labeled liposomes were recorded displaying an optical resolution low enough to resolve the 100 nm...... liposomes in the skin. The images revealed that virtually none of the liposomes remained intact beneath the skin surface. RICS two color cross correlation diffusion measurements of double labeled liposomes confirmed these observations. Our results suggest that the liposomes do not act as carriers...

  2. A to Z List of Cancer Drugs

    Science.gov (United States)

    ... and Cytarabine Liposome Decitabine Defibrotide Sodium Defitelio (Defibrotide Sodium) Degarelix Denileukin Diftitox Denosumab DepoCyt (Cytarabine Liposome) Dexamethasone Dexrazoxane Hydrochloride Dinutuximab Docetaxel Doxil (Doxorubicin Hydrochloride Liposome) Doxorubicin Hydrochloride ...

  3. Potential effect of cationic liposomes on interactions with oral bacterial cells and biofilms.

    Science.gov (United States)

    Sugano, Marika; Morisaki, Hirobumi; Negishi, Yoichi; Endo-Takahashi, Yoko; Kuwata, Hirotaka; Miyazaki, Takashi; Yamamoto, Matsuo

    2016-01-01

    Although oral infectious diseases have been attributed to bacteria, drug treatments remain ineffective because bacteria and their products exist as biofilms. Cationic liposomes have been suggested to electrostatically interact with the negative charge on the bacterial surface, thereby improving the effects of conventional drug therapies. However, the electrostatic interaction between oral bacteria and cationic liposomes has not yet been examined in detail. The aim of the present study was to examine the behavior of cationic liposomes and Streptococcus mutans in planktonic cells and biofilms. Liposomes with or without cationic lipid were prepared using a reverse-phase evaporation method. The zeta potentials of conventional liposomes (without cationic lipid) and cationic liposomes were -13 and 8 mV, respectively, and both had a mean particle size of approximately 180 nm. We first assessed the interaction between liposomes and planktonic bacterial cells with a flow cytometer. We then used a surface plasmon resonance method to examine the binding of liposomes to biofilms. We confirmed the binding behavior of liposomes with biofilms using confocal laser scanning microscopy. The interactions between cationic liposomes and S. mutans cells and biofilms were stronger than those of conventional liposomes. Microscopic observations revealed that many cationic liposomes interacted with the bacterial mass and penetrated the deep layers of biofilms. In this study, we demonstrated that cationic liposomes had higher affinity not only to oral bacterial cells, but also biofilms than conventional liposomes. This electrostatic interaction may be useful as a potential drug delivery system to biofilms.

  4. Liposomal packaging generates Wnt protein with in vivo biological activity.

    Directory of Open Access Journals (Sweden)

    Nathan T Morrell

    2008-08-01

    Full Text Available Wnt signals exercise strong cell-biological and regenerative effects of considerable therapeutic value. There are, however, no specific Wnt agonists and no method for in vivo delivery of purified Wnt proteins. Wnts contain lipid adducts that are required for activity and we exploited this lipophilicity by packaging purified Wnt3a protein into lipid vesicles. Rather than being encapsulated, Wnts are tethered to the liposomal surface, where they enhance and sustain Wnt signaling in vitro. Molecules that effectively antagonize soluble Wnt3a protein but are ineffective against the Wnt3a signal presented by a cell in a paracrine or autocrine manner are also unable to block liposomal Wnt3a activity, suggesting that liposomal packaging mimics the biological state of active Wnts. When delivered subcutaneously, Wnt3a liposomes induce hair follicle neogenesis, demonstrating their robust biological activity in a regenerative context.

  5. Chemical meningitis related to intra-CSF liposomal cytarabine.

    Science.gov (United States)

    Durand, Bénédicte; Zairi, Fahed; Boulanger, Thomas; Bonneterre, Jacques; Mortier, Laurent; Le Rhun, Emilie

    2017-10-01

    Therapeutic options of leptomeningeal metastases include intra-cerebrospinal fluid (CSF) chemotherapy. Among intra-CSF agents, liposomal cytarabine has advantages but can induce specific toxicities. A BRAF-V600E-mutated melanoma leptomeningeal metastases patient, treated by dabrafenib and liposomal cytarabine, presented after the first injection of liposomal cytarabine with hyperthermia and headaches. Despite sterile CSF/blood analyses, extended intravenous antibiotics were given and the second injection was delayed. The diagnosis of chemical meningitis was finally made. Dose reduction and appropriate symptomatic treatment permitted the administration of 15 injections of liposomal cytarabine combined with dabrafenib. A confirmation of the diagnosis of chemical meningitis is essential in order (1) not to delay intra-CSF or systemic chemotherapy or (2) to limit the administration of unnecessary but potentially toxic antibiotics.

  6. Syntheses and characterization of liposome-incorporated adamantyl aminoguanidines.

    Science.gov (United States)

    Šekutor, Marina; Štimac, Adela; Mlinarić-Majerski, Kata; Frkanec, Ruža

    2014-08-21

    A series of mono and bis-aminoguanidinium adamantane derivatives has been synthesized and incorporated into liposomes. They combine two biomedically significant molecules, the adamantane moiety and the guanidinium group. The adamantane moiety possesses the membrane compatible features while the cationic guanidinium subunit was recognized as a favourable structural feature for binding to complementary molecules comprising phosphate groups. The liposome formulations of adamantyl aminoguanidines were characterized and it was shown that the entrapment efficiency of the examined compounds is significant. In addition, it was demonstrated that liposomes with incorporated adamantyl aminoguanidines effectively recognized the complementary liposomes via the phosphate group. These results indicate that adamantane derivatives bearing guanidinium groups might be versatile tools for biomedical application, from studies of molecular recognition processes to usage in drug formulation and cell targeting.

  7. Stimuli-Responsive Liposomes for Controlled Drug Delivery

    KAUST Repository

    Li, Wengang

    2014-01-01

    Liposomes are promising drug delivery vesicles due to their biodegradibility, large volume and biocompatibility towards both hydrophilic and hydrophobic drugs. They suffer, however, from poor stability which limits their use in controlled delivery

  8. Pharmacokinetics of a 5-fluorouracil liposomal delivery system.

    Science.gov (United States)

    Simmons, S T; Sherwood, M B; Nichols, D A; Penne, R B; Sery, T; Spaeth, G L

    1988-01-01

    A liposomal delivery system was developed in an attempt to prolong ocular levels of 5-fluorouracil for glaucoma filtering surgery. The pharmacokinetics of the 5-fluorouracil liposomal delivery system were studied in normal pigmented rabbits with 5-fluorouracil labelled with carbon-14 (C-14). 14C 5-fluorouracil was incorporated into the liposomes at a concentration of 10 g/l and injected subconjunctivally in doses of 5 and 10 mg. Concentrations of 5-fluorouracil were assayed at 10 time intervals from 0.5 to 96 hours in cornea, sclera, and conjunctiva and at six time intervals from 0.5 to 12 hours in aqueous. Two peak concentrations were noted at approximately one and eight hours, with measurable levels present at 96 hours. This study demonstrates the ability of this liposomal delivery system to prolong levels of 5-fluorouracial in normal pigmented rabbits. PMID:3179257

  9. Atmospheric-pressure guided streamers for liposomal membrane disruption

    International Nuclear Information System (INIS)

    Svarnas, P.; Aleiferis, Sp.; Matrali, S. H.; Gazeli, K.; Clément, F.; Antimisiaris, S. G.

    2012-01-01

    The potential to use liposomes (LIPs) as a cellular model in order to study interactions of cold atmospheric-pressure plasma with cells is herein investigated. Cold atmospheric-pressure plasma is formed by a dielectric-barrier discharge reactor. Large multilamellar vesicle liposomes, consisted of phosphatidylcholine and cholesterol, are prepared by the thin film hydration technique, to encapsulate a small hydrophilic dye, i.e., calcein. The plasma-induced release of calcein from liposomes is then used as a measure of liposome membrane integrity and, consequently, interaction between the cold atmospheric plasma and lipid bilayers. Physical mechanisms leading to membrane disruption are suggested, based on the plasma characterization including gas temperature calculation.

  10. Bioreactor droplets from liposome-stabilized all-aqueous emulsions

    Science.gov (United States)

    Dewey, Daniel C.; Strulson, Christopher A.; Cacace, David N.; Bevilacqua, Philip C.; Keating, Christine D.

    2014-08-01

    Artificial bioreactors are desirable for in vitro biochemical studies and as protocells. A key challenge is maintaining a favourable internal environment while allowing substrate entry and product departure. We show that semipermeable, size-controlled bioreactors with aqueous, macromolecularly crowded interiors can be assembled by liposome stabilization of an all-aqueous emulsion. Dextran-rich aqueous droplets are dispersed in a continuous polyethylene glycol (PEG)-rich aqueous phase, with coalescence inhibited by adsorbed ~130-nm diameter liposomes. Fluorescence recovery after photobleaching and dynamic light scattering data indicate that the liposomes, which are PEGylated and negatively charged, remain intact at the interface for extended time. Inter-droplet repulsion provides electrostatic stabilization of the emulsion, with droplet coalescence prevented even for submonolayer interfacial coatings. RNA and DNA can enter and exit aqueous droplets by diffusion, with final concentrations dictated by partitioning. The capacity to serve as microscale bioreactors is established by demonstrating a ribozyme cleavage reaction within the liposome-coated droplets.

  11. Treatment of deep mycoses with liposomal amphotericin B.

    Science.gov (United States)

    Berenguer, J; Muñoz, P; Parras, F; Fernández-Baca, V; Hernández-Sampelayo, T; Bouza, E

    1994-06-01

    Amphotericin B is the mainstay of therapy of many deep mycoses, but its use is seriously hampered by dose-limiting nephrotoxicity. In this study a liposomal formulation of amphotericin B was administered to ten patients with proven deep mycoses: invasive aspergillosis (n = 4), deep candidiasis (n = 4) and zygomycosis (n = 2). The mean daily dosage of liposomal amphotericin B was 3.0 mg/kg (range 2.5 to 4 mg/kg), the mean total dosage of liposomal amphotericin B 2,781 mg (range 87 to 5,220 mg) and the mean duration of treatment 17 days (range 3 to 33 days). Treatment with liposomal amphotericin B was associated with little nephrotoxicity and an overall survival rate of 50%. The median increase of serum creatinine from baseline levels was 0.38 mg/dl (-1.2 to 2.6 mg/dl).

  12. Placing and shaping liposomes with reconfigurable DNA nanocages

    Science.gov (United States)

    Zhang, Zhao; Yang, Yang; Pincet, Frederic; C. Llaguno, Marc; Lin, Chenxiang

    2017-07-01

    The diverse structure and regulated deformation of lipid bilayer membranes are among a cell's most fascinating features. Artificial membrane-bound vesicles, known as liposomes, are versatile tools for modelling biological membranes and delivering foreign objects to cells. To fully mimic the complexity of cell membranes and optimize the efficiency of delivery vesicles, controlling liposome shape (both statically and dynamically) is of utmost importance. Here we report the assembly, arrangement and remodelling of liposomes with designer geometry: all of which are exquisitely controlled by a set of modular, reconfigurable DNA nanocages. Tubular and toroid shapes, among others, are transcribed from DNA cages to liposomes with high fidelity, giving rise to membrane curvatures present in cells yet previously difficult to construct in vitro. Moreover, the conformational changes of DNA cages drive membrane fusion and bending with predictable outcomes, opening up opportunities for the systematic study of membrane mechanics.

  13. Enzyme sensitive liposomes in chemotherapy and potentiation of immunotherapy

    DEFF Research Database (Denmark)

    Østrem, Ragnhild Garborg

    efficacy and induction of severe adverse effects. Interestingly, the pharmacokinetics and biodistribution of drugs can be substantially altered by encapsulation in liposomal drug delivery vehicles. The first chapter of this thesis gives a brief introduction to cancer followed by a discussion...... of the applicability of liposomes as drug delivery vehicles in cancer therapy. The second chapter describes the development of a liposome system with an inbuilt release mechanism triggered by secretory phospholipase A2 (sPLA2). This enzyme is expressed at elevated levels in many human cancers, and as such represents...... with an introduction to the cancer-immunity cycle and to how treatment approaches can aid this interplay. Subsequently it demonstrates that the presence of a functional immune system is important in the efficacy of liposomal oxaliplatin, and that this efficacy can be substantially enhanced by combination with...

  14. Do plasma proteins distinguish between liposomes of varying charge density?

    KAUST Repository

    Capriotti, Anna Laura; Caracciolo, Giulio; Cavaliere, Chiara; Foglia, Patrizia; Pozzi, Daniela; Samperi, Roberto; Laganà , Aldo

    2012-01-01

    efficient and more biocompatible liposomal formulations, the behavior of three CLs with different membrane charge densities was investigated. The proteins of the three coronas were identified by nano-liquid chromatography-tandem mass spectrometry

  15. The Effect of Polymer Backbone Chemistry on the Induction of the Accelerated Blood Clearance in Polymer Modified Liposomes

    KAUST Repository

    Kierstead, Paul H.; Okochi, Hideaki; Venditto, Vincent J.; Chuong, Tracy C.; Kivimae, Saul; Frechet, Jean; Szoka, Francis C.

    2015-01-01

    A variety of water-soluble polymers, when attached to a liposome, substantially increase liposome circulation half-life in animals. However, in certain conditions, liposomes modified with the most widely used polymer, polyethylene glycol (PEG

  16. Transcutaneous drug delivery by liposomes using fractional laser technology.

    Science.gov (United States)

    Fujimoto, Takahiro; Wang, Jian; Baba, Kazuki; Oki, Yuka; Hiruta, Yuki; Ito, Masayuki; Ito, Shinobu; Kanazawa, Hideko

    2017-07-01

    Transdermal delivery of hydrophilic peptides remains a challenge due to their poor cellular uptake and transdermal penetration. We hypothesize that combination of a CO 2 fractional laser to enhance percutaneous absorption and liposomes as transdermal carriers would improve skin penetration of hydrophilic drugs. NA. Liposomes were prepared using membrane fusion lipid dioleoylphosphatidylethanolamine, and used to deliver 5-carboxyfluorescein (CF) and fluorescein isothiocyanate-conjugated ovalbumin (OVA-FITC) as model hydrophilic peptide drugs. Liposome size was estimated by dynamic light scattering. Liposome uptake into murine macrophage cells and penetration or permeation into Yucatan micropig skin after irradiation by CO 2 fractional laser at varying energy levels (laser power and exposure duration) were investigated using Franz cell and fluorescence microscopy. Oxidative damage to the irradiated mouse skin was assessed by electron spin resonance. Size of CF and OVA-FITC encapsulated liposomes was 324 ± 75 nm. Cellular uptake of OVA-FITC delivered by liposomes was 10-fold higher (1,370 relative fluorescence units, RFU) than delivered in solution form (130 RFU). Fractional laser irradiation increased skin permeation rate of CF liposomes (0-10%) and OVA-FITC liposomes (4-40%) in a dose-dependent manner. Although peeling off the stratum corneum facilitated CF liposome penetration at low energy levels (2.69-3.29 J/cm 2 ; 10-20 W for 500 μs), drug permeation was similar (7-8%) in peeled or untreated skin at higher laser energy levels (6.06 J/cm 2 ; 20 W for 1,500 μs). FITC penetrated deeper in the skin after laser irradiation. However, OH, O2-, and VC reactive oxygen species were generated upon irradiation of the skin with a fractional CO 2 laser. Increasing laser power and irradiation, time increased liposome uptake by cells and penetration of peptide drugs across the skin in a dose-dependent manner. High-energy CO 2 fractional laser overcomes the

  17. Comparison of conventional chemotherapy, stealth liposomes and temperature-sensitive liposomes in a mathematical model.

    Directory of Open Access Journals (Sweden)

    Astrid Gasselhuber

    Full Text Available Various liposomal drug carriers have been developed to overcome short plasma half-life and toxicity related side effects of chemotherapeutic agents. We developed a mathematical model to compare different liposome formulations of doxorubicin (DOX: conventional chemotherapy (Free-DOX, Stealth liposomes (Stealth-DOX, temperature sensitive liposomes (TSL with intra-vascular triggered release (TSL-i, and TSL with extra-vascular triggered release (TSL-e. All formulations were administered as bolus at a dose of 9 mg/kg. For TSL, we assumed locally triggered release due to hyperthermia for 30 min. Drug concentrations were determined in systemic plasma, aggregate body tissue, cardiac tissue, tumor plasma, tumor interstitial space, and tumor cells. All compartments were assumed perfectly mixed, and represented by ordinary differential equations. Contribution of liposomal extravasation was negligible in the case of TSL-i, but was the major delivery mechanism for Stealth-DOX and for TSL-e. The dominant delivery mechanism for TSL-i was release within the tumor plasma compartment with subsequent tissue- and cell uptake of released DOX. Maximum intracellular tumor drug concentrations for Free-DOX, Stealth-DOX, TSL-i, and TSL-e were 3.4, 0.4, 100.6, and 15.9 µg/g, respectively. TSL-i and TSL-e allowed for high local tumor drug concentrations with reduced systemic exposure compared to Free-DOX. While Stealth-DOX resulted in high tumor tissue concentrations compared to Free-DOX, only a small fraction was bioavailable, resulting in little cellular uptake. Consistent with clinical data, Stealth-DOX resulted in similar tumor intracellular concentrations as Free-DOX, but with reduced systemic exposure. Optimal release time constants for maximum cellular uptake for Stealth-DOX, TSL-e, and TSL-i were 45 min, 11 min, and <3 s, respectively. Optimal release time constants were shorter for MDR cells, with ∼4 min for Stealth-DOX and for TSL-e. Tissue concentrations

  18. Engineering of an Inhalable DDA/TDB Liposomal Adjuvant

    DEFF Research Database (Denmark)

    Ingvarsson, Pall Thor; Yang, Mingshi; Mulvad, Helle

    2013-01-01

    The purpose of this study was to identify and optimize spray drying parameters of importance for the design of an inhalable powder formulation of a cationic liposomal adjuvant composed of dimethyldioctadecylammonium (DDA) bromide and trehalose-6,6'-dibehenate (TDB).......The purpose of this study was to identify and optimize spray drying parameters of importance for the design of an inhalable powder formulation of a cationic liposomal adjuvant composed of dimethyldioctadecylammonium (DDA) bromide and trehalose-6,6'-dibehenate (TDB)....

  19. Copper-64 labeled liposomes for imaging bone marrow

    International Nuclear Information System (INIS)

    Lee, Sang-gyu; Gangangari, Kishore; Kalidindi, Teja Muralidhar; Punzalan, Blesida; Larson, Steven M.; Pillarsetty, Naga Vara Kishore

    2016-01-01

    Introduction: Bone marrow is the soft tissue compartment inside the bones made up of hematopoietic cells, adipocytes, stromal cells, phagocytic cells, stem cells, and sinusoids. While [ 18 F]-FLT has been utilized to image proliferative marrow, to date, there are no reports of particle based positron emission tomography (PET) imaging agents for imaging bone marrow. We have developed copper-64 labeled liposomal formulation that selectively targets bone marrow and therefore serves as an efficient PET probe for imaging bone marrow. Methods: Optimized liposomal formulations were prepared with succinyl PE, DSPC, cholesterol, and mPEG-DSPE (69:39:1:10:0.1) with diameters of 90 and 140 nm, and were doped with DOTA-Bn-DSPE for stable 64 Cu incorporation into liposomes. Results: PET imaging and biodistribution studies with 64 Cu-labeled liposomes indicate that accumulation in bone marrow was as high as 15.18 ± 3.69%ID/g for 90 nm liposomes and 7.01 ± 0.92%ID/g for 140 nm liposomes at 24 h post-administration. In vivo biodistribution studies in tumor-bearing mice indicate that the uptake of 90 nm particles is approximately 0.89 ± 0.48%ID/g in tumor and 14.22 ± 8.07%ID/g in bone marrow, but respective values for Doxil® like liposomes are 0.83 ± 0.49%ID/g and 2.23 ± 1.00%ID/g. Conclusion: Our results indicate that our novel PET labeled liposomes target bone marrow with very high efficiency and therefore can function as efficient bone marrow imaging agents.

  20. Advanced strategies in liposomal cancer therapy

    DEFF Research Database (Denmark)

    Andresen, Thomas Lars; Jensen, Simon Skøde; Jørgensen, Kent

    2005-01-01

    is therefore of great importance. In the first part of this review, we present current strategies in the drug delivery field, focusing on site-specific triggered drug release from liposomes in cancerous tissue. Currently marketed drug delivery systems lack the ability to actively release the carried drug......, none of them have yet led to marketed drugs and are still far from achieving this goal. The most advanced and prospective technologies are probably the prodrug strategies where nontoxic drugs are carried and activated specifically in the malignant tissue by overexpressed enzymes. In the second part......Tumor specific drug delivery has become increasingly interesting in cancer therapy, as the use of chemotherapeutics is often limited due to severe side effects. Conventional drug delivery systems have shown low efficiency and a continuous search for more advanced drug delivery principles...

  1. Deciphering the Functional Composition of Fusogenic Liposomes

    Science.gov (United States)

    Kolašinac, Rejhana; Kleusch, Christian; Braun, Tobias; Merkel, Rudolf; Csiszár, Agnes

    2018-01-01

    Cationic liposomes are frequently used as carrier particles for nucleic acid delivery. The most popular formulation is the equimolar mixture of two components, a cationic lipid and a neutral phosphoethanolamine. Its uptake pathway has been described as endocytosis. The presence of an aromatic molecule as a third component strongly influences the cellular uptake process and results in complete membrane fusion instead of endocytosis. Here, we systematically varied all three components of this lipid mixture and determined how efficiently the resulting particles fused with the plasma membrane of living mammalian cells. Our results show that an aromatic molecule and a cationic lipid component with conical molecular shape are essential for efficient fusion induction. While a neutral lipid is not mandatory, it can be used to control fusion efficiency and, in the most extreme case, to revert the uptake mechanism back to endocytosis. PMID:29364187

  2. 40 CFR Appendix B to Subpart Nnn... - Free Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride

    Science.gov (United States)

    2010-07-01

    ... Insulation Resins by Hydroxylamine Hydrochloride B Appendix B to Subpart NNN of Part 63 Protection of...—Free Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride 1. Scope This method was... hydrochloric acid that is liberated when hydroxylamine hydrochloride reacts with formaldehyde to form...

  3. 21 CFR 522.1662b - Oxytetracycline hydrochloride with lidocaine injection.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride with lidocaine... FORM NEW ANIMAL DRUGS § 522.1662b Oxytetracycline hydrochloride with lidocaine injection. (a) Specifications. The drug contains 50 or 100 milligrams of oxytetracycline hydrochloride and 2 percent lidocaine...

  4. 21 CFR 520.1660c - Oxytetracycline hydrochloride tablets/boluses.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride tablets/boluses. 520....1660c Oxytetracycline hydrochloride tablets/boluses. (a) Specifications. Each tablet or bolus contains 250, 500, or 1,000 milligrams of oxytetracycline hydrochloride. (b) Sponsors. For sponsors in § 510...

  5. 21 CFR 524.1662b - Oxytetracycline hydrochloride, polymyxin B sulfate ophthalmic ointment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride, polymyxin B sulfate... DOSAGE FORM NEW ANIMAL DRUGS § 524.1662b Oxytetracycline hydrochloride, polymyxin B sulfate ophthalmic ointment. (a) Specifications. Each gram of the ointment contains oxytetracycline hydrochloride equivalent...

  6. 21 CFR 524.1662a - Oxytetracycline hydrochloride and hydrocortisone spray.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride and hydrocortisone... NEW ANIMAL DRUGS § 524.1662a Oxytetracycline hydrochloride and hydrocortisone spray. (a) Specifications. Each 3-ounce unit of oxytetracycline hydrochloride and hydrocortisone spray contains 300...

  7. 21 CFR 520.2345g - Tetracycline hydrochloride and sodium novobiocin tablets.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tetracycline hydrochloride and sodium novobiocin... § 520.2345g Tetracycline hydrochloride and sodium novobiocin tablets. (a) Specifications. Each tablet contains the equivalent of 60 milligrams of tetracycline hydrochloride and 60 milligrams of novobiocin, or...

  8. Enzymatic degradation of polymer covered SOPC-liposomes in relation to drug delivery

    DEFF Research Database (Denmark)

    Davidsen, Jesper; Vermehren, C.; Frøkjær, S.

    2001-01-01

    Polyethylenoxide (PEG) covered liposomes are used as lipid-based drug-delivery systems. In comparison to conventional liposomes the polymer-covered liposomes display a long circulation half-life in the blood stream. We investigate the influence of polyethyleneoxide-distearoylphosphatidylethanolam......Polyethylenoxide (PEG) covered liposomes are used as lipid-based drug-delivery systems. In comparison to conventional liposomes the polymer-covered liposomes display a long circulation half-life in the blood stream. We investigate the influence of polyethyleneoxide...

  9. Interaction of dipalmitoyl phosphatidylcholine (DPPC) liposomes and insulin

    Science.gov (United States)

    Mady, Mohsen M.; Elshemey, Wael M.

    2011-06-01

    Insulin, a peptide that has been used for decades in the treatment of diabetes, has well-defined properties and delivery requirements. Liposomes, which are lipid bilayer vesicles, have gained increasing attention as drug carriers which reduce the toxicity and increase the pharmacological activity of various drugs. The molecular interaction between (uncharged lipid) dipalmitoyl phosphatidylcholine (DPPC) liposomes and insulin has been characterized by using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction. The characteristic protein absorption band peaks, Amide I (at about 1660 cm-1) and Amide II band (at about 1546 cm-1) are potentially reduced in the liposome insulin complex. Wide-angle x-ray scattering measurements showed that the association of insulin with DPPC lipid of liposomes still maintains the characteristic DPPC diffraction peaks with almost no change in relative intensities or change in peak positions. The absence of any shift in protein peak positions after insulin being associated with DPPC liposomes indicates that insulin is successfully forming complex with DPPC liposomes with possibly no pronounced alterations in the structure of insulin molecule.

  10. The Role of Liposomal Bupivacaine in Value-Based Care.

    Science.gov (United States)

    Iorio, Richard

    Multimodal pain control strategies are crucial in reducing opioid use and delivering effective pain management to facilitate improved surgical outcomes. The utility of liposomal bupivacaine in enabling effective pain control in multimodal strategies has been demonstrated in several studies, but others have found the value of liposomal bupivacaine in such approaches to be insignificant. At New York University Langone Medical Center, liposomal bupivacaine injection and femoral nerve block were compared in their delivery of efficacious and cost-effective multimodal analgesia among patients undergoing total joint arthroplasty (TJA). Retrospective analysis revealed that including liposomal bupivacaine in a multimodal pain control protocol for TJA resulted in improved quality and efficiency metrics, decreased narcotic use, and faster mobilization, all relative to femoral nerve block, and without a significant increase in admission costs. In addition, liposomal bupivacaine use was associated with elimination of the need for patient-controlled analgesia in TJA. Thus, at Langone Medical Center, the introduction of liposomal bupivacaine to TJA has been instrumental in achieving adequate pain control, delivering high-level quality of care, and controlling costs.

  11. Modification of wool surface by liposomes for dyeing with weld.

    Science.gov (United States)

    Montazer, Majid; Zolfaghari, Alireza; Toliat, Taibeh; Moghadam, Mohammad Bameni

    2009-01-01

    In this research work, wool surface has been modified by liposome to investigate its effects on dyeing with weld, a yellow natural dye. To do this, samples were first treated with aluminium sulphate and afterward with different concentrations of liposomes at various temperatures for 30 minutes and, finally, dyed with weld at 75, 85, and 95 degrees C for 30, 45, and 60 minutes. K/S values of fabric samples were calculated and washing, light and rub fastness properties of the samples were indicated. The results proposed that the sample treated with 1% liposomes and dyed at 75 degrees C for 60 min has the highest K/S value. The central composite design (CCD) used for the experimental plan with three variables on the results of color strength and statistical analysis confirms the optimum conditions obtained by the experimental results. It was also found that washing, light, wet, and dry rub fastness properties of samples dyed with weld, including liposomes, have not significantly changed. The results of water drop absorption indicated that the hydrophobicity is higher for the samples pretreated with liposomes. The SEM picture of wool sample treated with mordant and liposomes and finally dyed with weld shows a coated layer on the fiber surface.

  12. Liposome distribution after intravenous and selective intraarterial infusion in dogs

    International Nuclear Information System (INIS)

    Wright, K.C.; Kasi, L.P.; Jahns, M.S.; Hashimoto, S.; Wallace, S.

    1990-01-01

    In an effort to improve hepatic uptake of liposomes for drug delivery, empty vesicles were administered by means of selective arterial infusion. Negatively charged, multilamellar liposomes were labeled with technetium-99m and infused into healthy adult dogs. Each dog received 100 mg/m2 of lipid over 10 minutes at 2 mL/min. Liposomes were administered via the common hepatic artery after proximal occlusion of the gastroduodenal artery, via the cranial mesenteric artery, and via the cephalic vein. Distribution (liver, spleen, and lungs) was determined by computer-assisted external imaging techniques. On the average, after arterial infusion, 69.2% of the total activity was located in the liver, 3.6% in the spleen, 3.2% in the lungs, and 3.5% in the general circulation. Following venous injection, 50.7% of the radioactivity was found in the liver, 9.1% in the spleen, 8.6% in the lungs, and 6.7% in the peripheral blood. Once the liposomes entered the systemic circulation, they were cleared at the same rate (half-life beta = 21.5 hours) independent of their route of administration. Increased hepatic liposome uptake should translate into higher local and lower systemic liposomal drug levels

  13. Calcium-Responsive Liposomes via a Synthetic Lipid Switch.

    Science.gov (United States)

    Lou, Jinchao; Carr, Adam J; Watson, Alexa J; Mattern-Schain, Samuel I; Best, Michael D

    2018-03-07

    Liposomal drug delivery would benefit from enhanced control over content release. Here, we report a novel avenue for triggering release driven by chemical composition using liposomes sensitized to calcium-a target chosen due to its key roles in biology and disease. To demonstrate this principle, we synthesized calcium-responsive lipid switch 1, designed to undergo conformational changes upon calcium binding. The conformational change perturbs membrane integrity, thereby promoting cargo release. This was shown through fluorescence-based release assays via dose-dependent response depending on the percentage of 1 in liposomes, with minimal background leakage in controls. DLS experiments indicated dramatic changes in particle size upon treatment of liposomes containing 1 with calcium. In a comparison of ten naturally occurring metal cations, calcium provided the greatest release. Finally, STEM images showed significant changes in liposome morphology upon treatment of liposomes containing 1 with calcium. These results showcase lipid switches driven by molecular recognition principles as an exciting avenue for controlling membrane properties. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Liposomal preparations of muramyl glycopeptides as immunomodulators and adjuvants.

    Science.gov (United States)

    Turánek, Jaroslav; Ledvina, Miroslav; Kasná, Andrea; Vacek, Antonín; Hríbalova, Vera; Krejcí, Josef; Miller, Andrew D

    2006-04-12

    The need for safe and structurally defined immunomodulators and adjuvants is increasing in connection with the recently observed marked increase in the prevalence of pathological conditions characterized by immunodeficiency. Important groups of such compounds are muramyl glycopeptides, analogs of muramyl dipeptide (MDP), glucosaminyl-muramyl dipeptide (GMDP), and desmuramylpeptides. We have designed and synthesized new types of analogs with changes in both the sugar and the peptide parts of the molecule that show a high immunostimulating and adjuvant activity and suppressed adverse side effects. The introduction of lipophilic residues has also improved their incorporation into liposomes, which represent a suitable drug carrier. The proliposome-liposome method is based on the conversion of the initial proliposome preparation into liposome dispersion by dilution with the aqueous phase. The description of a home-made stirred thermostated cell and its link-up with a liquid delivery system for a rapid and automated preparation of multilamellar liposomes at strictly controlled conditions (sterility, temperature, dilution rate and schedule) is presented. The cell has been designed for laboratory-scale preparation of liposomes (300-1000 mg of phospholipid per run) in a procedure taking less than 90 min. The method can be readily scaled up. Examples of adjuvant and immunostimulatory effect of liposomal preparation in mice model will be presented.

  15. Colestipol hydrochloride prophylaxis of diarrhea during pelvic radiotherapy

    International Nuclear Information System (INIS)

    Stryker, J.A.; Chung, C.K.; Layser, J.D.

    1983-01-01

    Thirty-three patients were randomized prior to pelvic radiotherapy to receive the bile acid-sequestering resin colestipol hydrochloride, 5 grams qid, during the entire time of their therapy or diphenoxylate hydrochloride and atropine sulfate 2.5-20 mg per day (control) if they experienced diarrhea. The colestipol patients also took diphenoxylate if they had diarrhea. The patients in the colestipol group often experienced nausea, vomiting, and abdominal cramps and 8 were forced to discontinue the drug. There was no difference in the weekly stool frequency between the colestipol and the control patients but the colestipol patients who took at least 50% of the prescribed dose required fewer diphenoxylate tablets than the controls. The data suggest that colestipol hydrochloride is not of value in preventing radiation-induced diarrhea because of the side effects associated with the drug, but the theory on which the use of bile acid-sequestering agents is based may be correct

  16. Clinical pharmacology of atovaquone and proguanil hydrochloride.

    Science.gov (United States)

    Beerahee, M

    1999-05-01

    Atovaquone and proguanil hydrochloride is a new antimalarial combination that is used for treatment and prophylaxis of malaria. The clinical pharmacology of atovaquone and proguanil was reviewed. Atovaquone is a highly lipophilic compound with low aqueous solubility, the absorption of which is limited by the rate and extent of dissolution. Dietary fat increases the rate and extent of atovaquone absorption, increasing AUC two- to threefold and C(max) fivefold over fasting. Proguanil is rapidly and extensively absorbed regardless of food intake. Atovaquone is highly protein bound (> 99%) but does not displace other highly protein bound drugs in vitro, indicating significant drug interactions arising from displacement are unlikely. Atovaquone is predominantly eliminated unchanged in feces, with negligible excretion in urine. Proguanil is partially metabolized and partially excreted unchanged in urine. Its principal metabolite, cycloguanil, is also excreted in urine. Metabolism of proguanil is mediated in the liver by the cytochrome P450 3A and 2C subfamilies. The elimination half-life of atovaquone is 2 to 3 days in adults and 1 to 2 days in children. The elimination half-lives of proguanil and cycloguanil are 12 to 15 hours in adults and children. Dosage adjustments based on body weight categories in children (1/4 dose for 11-20 kg, 1/2 dose for > 20-30 kg, 3/4 dose for > 30-40 kg, and full dose for > 40 kg) achieve plasma concentrations that are safe and effective during prophylaxis and treatment of malaria. No dose adjustments for race, proguanil metabolizer status, gender, or elderly patients are needed, or for patients with mild to moderately impaired renal or hepatic function. The clinical pharmacology of atovaquone and proguanil provides a rationale for the dosing regimens recommended for treatment and prophylaxis of malaria.

  17. Placental transfer of ritodrine hydrochloride in sheep

    International Nuclear Information System (INIS)

    Fujimoto, Seiichiro; Akahane, Masuo; Uzuki Katsuya; Inagawa, Akira; Sakai, Keiichiro; Sakai, Akira

    1984-01-01

    This study examines the placental passage of ritodrine hydrochloride in relation to the drug's effects on the fetal circulation. Studies were carried out on nine mulliparous pregnant (120-140 days) ewes with chronically implanted cannulae of measurements of maternal and fetal arterial pressures and for blood sampling. One group of animals received sequential infusions of doses ranging from 0.1 to 30 μg/kg per min for 30 min (group 1). A second group was given a constant infusion of the drug at a dose of 3.0 μg/kg per min for 4 h (group 2). The peak concentrations of ritodrine in maternal and fetal blood were determined by radioimmunoassay. In group 1 they were 313.4 +- 24.1 ng/ml (mean +-S.E.) and 12.6 +- 3.7 ng/ml at the finish of 30.0 ug/kg per min infusion for maternal and fetal blood, respectively. In group 2, maternal drug levels were 81.3 +- 20.4 ng/ml after 30 min and 95.9 +- 17.1 ng/ml after 4 h of the infusion. Fetal plasma concentrations increased slowly from trace levels at 30 min to 3.3 +- 0.7 ng/ml at 4 h. Fetal blood pressure and heart rate did not show any significant changes during and after the infusion of ritodrine in both treatment groups. The findings demonstrate the maternal administration of ritodrine produces no significant effects on the circulatory system of the fetal lamb because of the low transplacental passage of this drug. (author)

  18. Geometry optimization of antimuscarinic, anticholinergic and antispasmodic aprophen hydrochloride

    International Nuclear Information System (INIS)

    Bano, F.; Akhter, N.

    2013-01-01

    Aprophen hydrochloride extensively used as anticholinergic, antimuscarinnin and antispasmodic agent. Structure based drug designed is based on the firm understanding of molecular recognition between active site group and interacting molecules ,it is strategy that become as integral part of modem drug discovery. The aim of present study is find out the minimum potential energy for aprophen hydrochloride. The potential energy of the molecule in molecular mechanics calculated by using force field concept. Potential energy effect the inter action of drug molecule with receptor these properties could be use to synthesize new drug candidates with improve pharmacological and therapeutic activity. (author)

  19. Liposome Delivery Systems for Inhalation: A Critical Review Highlighting Formulation Issues and Anticancer Applications.

    Science.gov (United States)

    Rudokas, Mindaugas; Najlah, Mohammad; Alhnan, Mohamed Albed; Elhissi, Abdelbary

    2016-01-01

    This is a critical review on research conducted in the field of pulmonary delivery of liposomes. Issues relating to the mechanism of nebulisation and liposome composition were appraised and correlated with literature reports of liposome formulations used in clinical trials to understand the role of liposome size and composition on therapeutic outcome. A major highlight was liposome inhalation for the treatment of lung cancers. Many in vivo studies that explored the potential of liposomes as anticancer carrier systems were evaluated, including animal studies and clinical trials. Liposomes can entrap anticancer drugs and localise their action in the lung following pulmonary delivery. The safety of inhaled liposomes incorporating anticancer drugs depends on the anticancer agent used and the amount of drug delivered to the target cancer in the lung. The difficulty of efficient targeting of liposomal anticancer aerosols to the cancerous tissues within the lung may result in low doses reaching the target site. Overall, following the success of liposomes as inhalable carriers in the treatment of lung infections, it is expected that more focus from research and development will be given to designing inhalable liposome carriers for the treatment of other lung diseases, including pulmonary cancers. The successful development of anticancer liposomes for inhalation may depend on the future development of effective aerosolisation devices and better targeted liposomes to maximise the benefit of therapy and reduce the potential for local and systemic adverse effects. © 2016 S. Karger AG, Basel.

  20. Antibody-Hapten Recognition at the Surface of Functionalized Liposomes Studied by SPR: Steric Hindrance of Pegylated Phospholipids in Stealth Liposomes Prepared for Targeted Radionuclide Delivery

    Directory of Open Access Journals (Sweden)

    Eliot. P. Botosoa

    2011-01-01

    Full Text Available Targeted PEGylated liposomes could increase the amount of drugs or radionuclides delivered to tumor cells. They show favorable stability and pharmacokinetics, but steric hindrance of the PEG chains can block the binding of the targeting moiety. Here, specific interactions between an antihapten antibody (clone 734, specific for the DTPA-indium complex and DTPA-indium-tagged liposomes were characterized by surface plasmon resonance (SPR. Non-PEGylated liposomes fused on CM5 chips whereas PEGylated liposomes did not. By contrast, both PEGylated and non-PEGylated liposomes attached to L1 chips without fusion. SPR binding kinetics showed that, in the absence of PEG, the antibody binds the hapten at the surface of lipid bilayers with the affinity of the soluble hapten. The incorporation of PEGylated lipids hinders antibody binding to extents depending on PEGylated lipid fraction and PEG molecular weight. SPR on immobilized liposomes thus appears as a useful technique to optimize formulations of liposomes for targeted therapy.

  1. From conventional to stealth liposomes: a new frontier in cancer chemotherapy.

    Science.gov (United States)

    Cattel, Luigi; Ceruti, Maurizio; Dosio, Franco

    2003-01-01

    Many attempts have been made to achieve good selectivity to targeted tumor cells by preparing specialized carrier agents that are therapeutically profitable for anticancer therapy. Among these, liposomes are the most studied colloidal particles thus far applied in medicine and in particular in antitumor therapy. Although they were first described in the 1960s, only at the beginning of 1990s did the first therapeutic liposomes appear on the market. The first-generation liposomes (conventional liposomes) comprised a liposome-containing amphotericin B, Ambisome (Nexstar, Boulder, CO, USA), used as an antifungal drug, and Myocet (Elan Pharma Int, Princeton, NJ, USA), a doxorubicin-containing liposome, used in clinical trials to treat metastatic breast cancer. The second-generation liposomes ("pure lipid approach") were long-circulating liposomes, such as Daunoxome, a daunorubicin-containing liposome approved in the US and Europe to treat AIDS-related Kaposi's sarcoma. The third-generation liposomes were surface-modified liposomes with gangliosides or sialic acid, which can evade the immune system responsible for removing liposomes from circulation. The fourth-generation liposomes, pegylated liposomal doxorubicin, were called "stealth liposomes" because of their ability to evade interception by the immune system, in the same way as the stealth bomber was able to evade radar. Actually, the only stealth liposome on the market is Caelyx/Doxil (Schering-Plough, Madison NJ, USA), used to cure AIDS-related Kaposi's sarcoma, resistant ovarian cancer and metastatic breast cancer. Pegylated liposomal doxorubicin is characterized by a very long-circulation half-life, favorable pharmacokinetic behavior and specific accumulation in tumor tissues. These features account for the much lower toxicity shown by Caelyx in comparison to free doxorubicin, in terms of cardiotoxicity, vesicant effects, nausea, vomiting and alopecia. Pegylated liposomal doxorubicin also appeared to be less

  2. Tissue distribution of radiolabeled phosphatidylserine-containing liposome in mice

    Energy Technology Data Exchange (ETDEWEB)

    Borborema, Samanta E.T.; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Biotecnologia], e-mail: samanta@usp.br, e-mail: nnascime@ipen.br; Andrade Junior, Heitor F. de [Instituto de Medicina Tropical de Sao Paulo (IMTSP), Sao Paulo, SP (Brazil)], e-mail: hfandrad@usp.br; Osso Junior, Joao A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Radiofarmacia], e-mail: jaosso@ipen.br

    2009-07-01

    Liposomes are used as drug delivery systems to modify pharmacokinetic of drugs and also to improve their action in target cells. Liposomes containing phosphatidylserine are efficiently eliminated from the blood by cells of the mononuclear phagocytic system (MPS), predominantly Kupffer cells in the liver. In this way, this is a valuable approach to treat infectious diseases involving MPS, especially leishmaniasis. Leishmaniasis is a severe parasitic disease, caused by intramacrophage protozoa Leishmania sp., and is fatal if left untreated. Leishmania resides mainly in the liver and the spleen. Antileishmanial agents containing-liposomes showed more effective therapies with reduction of toxicity and adverse side effects. The purpose of this study was to investigate the tissue distribution of radioactive meglumine antimoniate encapsulated in phosphatidylserine-containing liposome. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor to produce antimony radiotracers, {sup 122}Sb and {sup 124}Sb, and encapsulated in liposome. Healthy mice received a single intraperitoneal dose of the radiolabeled drug. Analysis of the mean radioactive tissue concentration-time data curves showed that liver and spleen had the highest levels of radioactivity. In addition these levels of drug remained for more than 48 hours. The dominant route of elimination was via biliary excretion with slow rate. Small fraction of the drug was found in the kidneys with very fast elimination. In conclusion, the phosphatidylserine-containing liposome showed to be a very useful tool to target antileishmanial agents to MPS and to sustain the drug levels for longer times. Besides, radiolabeled liposome is the easiest approach to perform biodistribution evaluation. (author)

  3. Tissue distribution of radiolabeled phosphatidylserine-containing liposome in mice

    International Nuclear Information System (INIS)

    Borborema, Samanta E.T.; Nascimento, Nanci do; Osso Junior, Joao A.

    2009-01-01

    Liposomes are used as drug delivery systems to modify pharmacokinetic of drugs and also to improve their action in target cells. Liposomes containing phosphatidylserine are efficiently eliminated from the blood by cells of the mononuclear phagocytic system (MPS), predominantly Kupffer cells in the liver. In this way, this is a valuable approach to treat infectious diseases involving MPS, especially leishmaniasis. Leishmaniasis is a severe parasitic disease, caused by intramacrophage protozoa Leishmania sp., and is fatal if left untreated. Leishmania resides mainly in the liver and the spleen. Antileishmanial agents containing-liposomes showed more effective therapies with reduction of toxicity and adverse side effects. The purpose of this study was to investigate the tissue distribution of radioactive meglumine antimoniate encapsulated in phosphatidylserine-containing liposome. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor to produce antimony radiotracers, 122 Sb and 124 Sb, and encapsulated in liposome. Healthy mice received a single intraperitoneal dose of the radiolabeled drug. Analysis of the mean radioactive tissue concentration-time data curves showed that liver and spleen had the highest levels of radioactivity. In addition these levels of drug remained for more than 48 hours. The dominant route of elimination was via biliary excretion with slow rate. Small fraction of the drug was found in the kidneys with very fast elimination. In conclusion, the phosphatidylserine-containing liposome showed to be a very useful tool to target antileishmanial agents to MPS and to sustain the drug levels for longer times. Besides, radiolabeled liposome is the easiest approach to perform biodistribution evaluation. (author)

  4. Histopathologic Study Following Administration of Liposome-Encapsulated Hemoglobin in the Normovolemic Rat

    National Research Council Canada - National Science Library

    Rudolph, Alan

    1995-01-01

    ... bovine hemoglobin in the normovolemic rat. We have also examined the administration of the liposome vehicle, tetrameric bovine hemoglobin, and liposome encapsulated bovine hemoglobin that had been lyophilized with 300 mM trehalose...

  5. Encapsulation of phytosterols and phytosterol esters in liposomes made with soy phospholipids by high pressure homogenization.

    Science.gov (United States)

    Wang, Fan C; Acevedo, Nuria; Marangoni, Alejandro G

    2017-11-15

    Phytosterols and phytosterol esters were encapsulated within large unilamellar liposomes prepared with soy phospholipids using a microfluidizer. The average particle diameter of these liposomal vesicles increased with increasing amounts of encapsulated phytosterols, especially with increasing free sterol content. The phytosterol content, liposomal particle size, and phytosterol encapsulation efficiency started to plateau when liposomes were prepared with MOPS buffer dispersions that contained 50 mg ml -1 soy phospholipid and more than 4% phytosterol blend, suggesting the saturation of phytosterol encapsulation. We proposed an encapsulation mechanism of free sterols and phytosterol esters in liposomes, where free sterols were mainly encapsulated within the lumen of these liposomes as crystals, and sterol esters and some free sterols were incorporated within the phospholipid bilayer of the liposomal membrane. The results from this work could provide the pharmaceutical and nutraceutical industries a practical method to produce loaded liposomes using inexpensive phospholipid mixtures for the delivery of bioactive ingredients.

  6. Surface Functionalization and Targeting Strategies of Liposomes in Solid Tumor Therapy: A Review

    Science.gov (United States)

    Riaz, Muhammad Kashif; Riaz, Muhammad Adil; Zhang, Xue; Lin, Congcong; Wong, Ka Hong; Chen, Xiaoyu; Lu, Aiping

    2018-01-01

    Surface functionalization of liposomes can play a key role in overcoming the current limitations of nanocarriers to treat solid tumors, i.e., biological barriers and physiological factors. The phospholipid vesicles (liposomes) containing anticancer agents produce fewer side effects than non-liposomal anticancer formulations, and can effectively target the solid tumors. This article reviews information about the strategies for targeting of liposomes to solid tumors along with the possible targets in cancer cells, i.e., extracellular and intracellular targets and targets in tumor microenvironment or vasculature. Targeting ligands for functionalization of liposomes with relevant surface engineering techniques have been described. Stimuli strategies for enhanced delivery of anticancer agents at requisite location using stimuli-responsive functionalized liposomes have been discussed. Recent approaches for enhanced delivery of anticancer agents at tumor site with relevant surface functionalization techniques have been reviewed. Finally, current challenges of functionalized liposomes and future perspective of smart functionalized liposomes have been discussed. PMID:29315231

  7. Surface Functionalization and Targeting Strategies of Liposomes in Solid Tumor Therapy: A Review

    Directory of Open Access Journals (Sweden)

    Muhammad Kashif Riaz

    2018-01-01

    Full Text Available Surface functionalization of liposomes can play a key role in overcoming the current limitations of nanocarriers to treat solid tumors, i.e., biological barriers and physiological factors. The phospholipid vesicles (liposomes containing anticancer agents produce fewer side effects than non-liposomal anticancer formulations, and can effectively target the solid tumors. This article reviews information about the strategies for targeting of liposomes to solid tumors along with the possible targets in cancer cells, i.e., extracellular and intracellular targets and targets in tumor microenvironment or vasculature. Targeting ligands for functionalization of liposomes with relevant surface engineering techniques have been described. Stimuli strategies for enhanced delivery of anticancer agents at requisite location using stimuli-responsive functionalized liposomes have been discussed. Recent approaches for enhanced delivery of anticancer agents at tumor site with relevant surface functionalization techniques have been reviewed. Finally, current challenges of functionalized liposomes and future perspective of smart functionalized liposomes have been discussed.

  8. Etoposide Incorporated into Camel Milk Phospholipids Liposomes Shows Increased Activity against Fibrosarcoma in a Mouse Model

    Directory of Open Access Journals (Sweden)

    Hamzah M. Maswadeh

    2015-01-01

    Full Text Available Phospholipids were isolated from camel milk and identified by using high performance liquid chromatography and gas chromatography-mass spectrometry (GC/MS. Anticancer drug etoposide (ETP was entrapped in liposomes, prepared from camel milk phospholipids, to determine its activity against fibrosarcoma in a murine model. Fibrosarcoma was induced in mice by injecting benzopyrene (BAP and tumor-bearing mice were treated with various formulations of etoposide, including etoposide entrapped camel milk phospholipids liposomes (ETP-Cam-liposomes and etoposide-loaded DPPC-liposomes (ETP-DPPC-liposomes. The tumor-bearing mice treated with ETP-Cam-liposomes showed slow progression of tumors and increased survival compared to free ETP or ETP-DPPC-liposomes. These results suggest that ETP-Cam-liposomes may prove to be a better drug delivery system for anticancer drugs.

  9. Oxidative stability of Liposomes composed of docosahexaenoic acid-containing phospholipids

    DEFF Research Database (Denmark)

    Vikbjerg, Anders Falk; Andresen, Thomas Lars; Jørgensen, Kent

    2007-01-01

    Oxidative stability of liposomes made of (Docosahexaenoic acid) DHA-containing phosphatidylcholine (PC) was examined during preparation and storage. After preparation of the liposomes, the concentration of primary (conjugated dienes) and secondary oxidation products (Thiobarbituric acid...

  10. Exploring the fate of liposomes in the intestine by dynamic in vitro lipolysis

    DEFF Research Database (Denmark)

    Parmentier, Johannes; Thomas, Nicky; Müllertz, Anette

    2012-01-01

    precipitation was detected during the lipolysis assay, despite pronounced lipolytic degradation and change in vesicle size. In conclusion, the tested dynamic in vitro lipolysis model is suitable for the assessment of liposome stability in the intestine. Furthermore, liposomes might be a useful alternative......Liposomes are generally well tolerated drug delivery systems with a potential use for the oral route. However, little is known about the fate of liposomes during exposure to the conditions in the gastro-intestinal tract (GIT). To gain a better understanding of liposome stability in the intestine......, a dynamic in vitro lipolysis model, which so far has only been used for the in vitro characterisation of other lipid-based drug delivery systems, was applied to different liposomal formulations. Liposome size and phospholipid (PL) digestion were determined as two markers for liposome stability. In addition...

  11. Development of method of tritium labeling of pharmacological preparate of drotaverine hydrochloride (NOSPA)

    International Nuclear Information System (INIS)

    Kim, A.A.; Djuraeva, G.T.; Shukurov, B.V.

    2004-01-01

    Full text: The method for tritium labeling of pharmacological preparate of drotaverine hydrochloride (no spa) was developed. Drotaverine hydrochloride was labeled by thermally activated tritium in apparatus for tritium labeling. The optimum regime of labeling was selected. The system of purification of tritium labeled drotaverine hydrochloride by thin layer chromatography (TLC) has been developed. The TLC system of purification of tritium labeled drotaverine hydrochloride was developed. Tritium labeled preparation of drotaverine hydrochloride was purified by TLC on silicagel in system isopropanol: ammonia: water (8:1:1). We found appearance of additional fractions in tritium labeled preparation of drotaverine hydrochloride that testifies to partial transformation of drotaverine hydrochloride during procedure of labeling. Application of TLC for purification of tritium labeled preparation allows to purify completely drotaverine hydrochloride of by-products. The output of purified tritium labeled preparation of drotaverine hydrochloride was about 25 %. The received preparation had specific radioactivity - 3,2 MBq/mg, radiochemical purity of a preparation was 95 %. TLC purification seems inexpensive, fast and suitable for purification of tritium-labeled drotaverine hydrochloride. Thus developed method allows obtain tritium labeled preparation of drotaverine hydrochloride (no - spa), suitable for medical and biologic researches

  12. Amantadine hydrochloride in the treatment of parkinsonism: A ...

    African Journals Online (AJOL)

    Subjective mood elevation was not confirmed by statistical analysis. Gait, voice control, jaw tremor and salivation showed no statistical improvement, while eye convergence may be adversely affected. Side-effects were minimal. Amantadine hydrochloride (Symmetrel, Geigy) appears to have real value in the treatment of ...

  13. Systematic analysis of trimazolin hydrochloride as adrenergic vasoconstrictor

    Directory of Open Access Journals (Sweden)

    Nikolić Goran

    2008-01-01

    Full Text Available Trimazolin-hydrochloride, which is used as a pharmaceutically active component (adrenergic vasoconstrictor for the production of decongestive preparations, was investigated in this paper by performing systematic analysis. In domestic and foreign pharmacopoeias, as well as in scientific and patent literature, there are no data on trimazolin and the methods of its investigation. Systematic analysis involves two investigation phases. A complete physicochemical characterization of the synthesized substance was done by previous investigation. In the second phase, a chemical structure of the synthesized pharmacologically active substance was confirmed to a certain degree of certainty by using the absorption spectroscopic methods (FTIR, UV-VIS, 1H-NMR. The spectroscopic methods used proved to be successful at identifying and investigating the purity of trimazolin hydrochloride. Liquid (RP-HPLC chromatography was used for the analysis of trimazolin hydrochloride in the nasal preparation (Adrianol. The method of titrimetric analysis was developed with the aim of quantitative determination of trimazolin hydrochloride in decongestive preparations.

  14. Pharmaceutical development of an intravenous dosage form of diacetylmorphine hydrochloride

    NARCIS (Netherlands)

    Klous, Marjolein G.; Nuijen, Bastiaan; van den Brink, Wim; van Ree, Jan M.; Beijnen, Jos H.

    2004-01-01

    A solid dosage form for multiple use was developed for parenteral administration of diacetylmorphine in a clinical trial on co-prescription of heroin to heroin addicts. A 300-mg/mL diacetylmorphine hydrochloride solution was lyophilised as 10-mL aliquots in 30-mL glass vials, to be reconstituted to

  15. Effect of donepezil hydrochloride on normal-tension glaucoma

    International Nuclear Information System (INIS)

    Yoshida, Yukiko; Sugiyama, Tetsuya; Ikeda, Tsunehiko; Utsunomiya, Keita; Ogura, Yasuharu; Narabayashi, Isamu

    2007-01-01

    Peroral donepezil hydrochloride is claimed to be effective for Alzheimer disease, by elevating concentration of acetylcholine in the brain resulting in improved recognition and intracerebral circulation. It has been reported that some cases of normal-tension glaucoma (NTG) show cerebral circulation similar to patients of Alzheimer disease. The purpose of this study was to evaluate the effect of donepezil hydrochloride on NTG. This study was made on 10 eyes of 5 NTG patients who showed cerebral circulation similar to Alzheimer disease by 123 I-iofetamine (IMP) single photon emission computed tomography (SPECT). The series comprised 3 males and 2 females. Their age ranged from 64 to 79 years, average 69 years. They were given donepezil hydrochloride at the daily dosis of 5 mg for 6 months. Circulation in the optic nervehead was measured by laser speckle flowmetry. Circulation in the brain and optic nervehead significantly increased after 6 months of treatment. MD value by Humphrey tonometer improved in 5 eyes (50%). There was no change in intraocular pressure. Peroral donepezil hydrochloride may improve optic neuropathy in NTG through its neuroprotective action. (author)

  16. Determination of methadone hydrochloride in a maintenance dosage formulation.

    Science.gov (United States)

    Hoffmann, T J; Thompson, R D

    1975-07-01

    A colorimetric method for direct quantitative assay of methadone hydrochloride in liquid oral dosage forms is presented. The procedure involves the formation of a dye complex with bromothymol blue buffer solution. The resultant complex is extracted with benzene and measured spectrophotometrically. Duplicate tests on the formulation showed 99.2% of the labeled amount of methadone.

  17. Microencapsulation of tramadol hydrochloride and physicochemical evaluation of formulations

    International Nuclear Information System (INIS)

    Murtaza, G.; Ahmad, M.

    2009-01-01

    The present project involves the microencapsulation of tramadol hydrochloride with ethocel using a non-solvent addition coacervation technique. The concentration of ethocel was varied to get a prolonged release profile. Then microparticles were compressed into tablets to study the variation of drug release between the microparticles and tablets. The microparticles were off white, aggregated and irregular in morphology having good percentage entrapment efficiency and percentage production yield. Dissolution study was made using USP XXIV apparatus I and II respectively, in 900 ml double distilled water at 50 rpm maintained at 37 degree C. An Initial burst effect was noted in the drug release behavior. Polyisobutylene concentration affected inversely the rate of drug release from microparticles. Dissolution media and stirring speed affected insignificantly (p>.05) the release pattern. Tramadol hydrochloride tablets showed good stability and reproducibility. UV and FTIR spectroscopy and X-Ray diffractometry proved that tramadol hydrochloride was completely and uniformly distributed in ethocel with out any strong interaction. The mechanism of drug release was anomalous diffusion that was best fit to Higuchi's equation. It can be concluded that multi-unit, slow-release tramadol hydrochloride microparticles can be formulated efficiently with non-solvent addition coacervation technique using ethocel. (author)

  18. Surface tension of compositions of polyhexametyleneguanidine hydrochloride - surfactants

    Directory of Open Access Journals (Sweden)

    S. Kumargaliyeva

    2012-12-01

    Full Text Available We made up songs bactericidal polyhexamethyleneguanidine hydrochloride (metacyde with the surface-active substances - anionic sodium dodecylsulfate, cationic cetylpyridinium bromide, and nonionic Tween-80 and measured the surface tension of water solutions. The study showed that the composition metacyde with surface-active agents have a greater surface activity than the individual components.

  19. IMPACT OF STRESS FACTORS ON OPTICAL ISOMERISM OF BENAZEPRIL HYDROCHLORIDE.

    Science.gov (United States)

    Kublin, Elżbieta; Czerwińska, Krystyna; Wyszomirska, Elżbieta; Zajaczkowską, Anna; Malanowicz, Ewa; Kaczmarska-Graczyk, Barbara; Mazurek, Aleksander P

    2015-01-01

    Benazepril hydrochloride contains two stereogenic centers, but is currently available as single enantiomer (S,S configuration) for the treatment of hypertension. Its enantiomer (R,R configuration) and the diastereoisomeric pair (R,S and S,R) can be regarded as impurities. Stereochemical stability of S,S isomer of benazepril hydrochloride and its potential susceptibility to conversion in the.active substance and in Lisonid tablets were examinated. The separation with the use of the TLC method with the following system: chromatographic plates Chiralplate and a mobile phase: methanol - acetonitrile - 1 mM copper(II) acetate (4 : 2 : 4, v/v/v) with saturation of glacial acetic acid for 1 h and the HPLC method system: Chiral AGP column (150 x 4.0 man x 5 µm) and a mobile phase: phosphate buffer pH = 6.0 - methanol (80 : 20, v/v) were obtained. Active substance - benazepril hydrochloride and Lisonid tablets 20 mg were subjected to the impact of different stress factors. Samples were examined after 1 and 6 weeks. It was found that none of the applied stress factors caused the transformation of the S,S enantiomer of benazepril hydrochloride in the substance and tablets to other identified stereoisomers - only the compound decomposition has occurred.

  20. Formulation of Extended-Release Metformin Hydrochloride Matrix ...

    African Journals Online (AJOL)

    Methods: Various metformin hydrochloride formulations containing a hydrophobic carrier (stearic acid) and a hydrophilic polymer (polyethylene oxide) were prepared using a 32 factorial design. ... The release data were subjected to various release kinetic models and also compared with those of a commercial brand.

  1. Amides and Hydrazides from Amine and Hydrazine Hydrochlorides.

    Science.gov (United States)

    Shama, Sami A.; Tran, Thuan L.

    1978-01-01

    This safe and efficient procedure for the synthesis of N-substituted amides and hydrazides is a modification of the Schotten-Bausmann procedure in which the amine or hydrazide is replaced by the corresponding hydrochloride salt, and the use of alkali is eliminated. (Author/BB)

  2. The efficacy of two bupivacaine hydrochloride injection products

    African Journals Online (AJOL)

    1996-06-06

    Jun 6, 1996 ... stances majority of o the survey t the time hamstrung g staff. itive hes to ... hydrochloride injection products was investigated in patients who ... upon the concentration, dose, route of application, and ... Practice guidelines.~.5 .... GUIdelines on Ihe Qualoty. safety and efficacy Of mra.cmal prOducts for human.

  3. Interactive effect of dietary protein level and zilpaterol hydrochloride ...

    African Journals Online (AJOL)

    Bonsmara type steers were used to determine the effect of dietary zilpaterol hydrochloride (ZH) in combination with different dietary crude protein (CP) levels (100, 120 and 140 g CP/kg) on growth performance and meat quality. Treatment groups (T) consisted of 12 steers each. T1 – 100 g CP/kg + 0.15 mg ZH/kg live weight ...

  4. Contribution à la formulation et à l'évaluation de liposomes d'ATP

    OpenAIRE

    Vincourt-Vitse, Véronique,

    2012-01-01

    ATP liposome incorporating hepatic ligands may contribute to improve the energetic status of the liver graft. In a first phase of development, it has been emphasized the great need of stabilizing the liposome (i) and of validating a cellular model with an altered energetic status in order to test the formulations of interest. To provide a stable liposomal preparation, different strategies have been carried out to freeze-dry liposome with or without ATP. Sucrose and trehalose better stabilize ...

  5. In vivo and in vitro evaluation of octyl methoxycinnamate liposomes

    Directory of Open Access Journals (Sweden)

    de Carvalho Varjão Mota A

    2013-12-01

    Full Text Available Aline de Carvalho Varjão Mota,1 Zaida Maria Faria de Freitas,1 Eduardo Ricci Júnior,1 Gisela Maria Dellamora-Ortiz,1 Ralph Santos-Oliveira,2 Rafael Antonio Ozzetti,3 André Luiz Vergnanini,3 Vanessa Lira Ribeiro,4 Ronald Santos Silva,4 Elisabete Pereira dos Santos11Faculty of Pharmacy, Federal University of Rio de Janeiro, 2Nuclear Engineering Institute, National Nuclear Energy Commission, 3Allergisa Dermatocosmetic Research, University of Campinas, São Paulo, 4Pharmacology and Toxicology Department, National Insitute of Quality Control in Health, Oswaldo Cruz Foundation, Rio de Janeiro, BrazilAbstract: Solar radiation causes damage to human skin, and photoprotection is the main way to prevent these harmful effects. The development of sunscreen formulations containing nanosystems is of great interest in the pharmaceutical and cosmetic industries because of the many potential benefits. This study aimed to develop and evaluate an octyl methoxycinnamate (OMC liposomal nanosystem (liposome/OMC to obtain a sunscreen formulation with improved safety and efficacy by retaining OMC for longer on the stratum corneum.Methods: The liposome/OMC nanostructure obtained was tested for enzymatic hydrolysis with lipase from Rhizomucor miehei and biodistribution with liposomes labeled with technetium-99m. The liposome/OMC formulation was then incorporated in a gel formulation and tested for ocular irritation using the hen’s egg test-chorio-allantoic membrane (HET-CAM assay, in vitro and in vivo sun protection factor, in vitro release profile, skin biometrics, and in vivo tape stripping.Results: The liposome/OMC nanosystem was not hydrolyzed from R. miehei by lipase. In the biodistribution assay, the liposome/OMC formulation labeled with technetium-99m had mainly deposited in the skin, while for OMC the main organ was the liver, showing that the liposome had higher affinity for the skin than OMC. The liposome/OMC formulation was classified as nonirritating in

  6. Poly(amino acid)s: next-generation coatings for long-circulating liposomes

    NARCIS (Netherlands)

    Romberg, B.

    2007-01-01

    Incorporation of a lipid conjugate of a water-soluble polymer into liposomes can reduce the adhesion of plasma proteins that would otherwise cause rapid recognition and removal of the liposomes by phagocytes. Such polymer-coated liposomes show prolonged circulation property and passive targeting to

  7. Effects of 5-nitro-2-furaldehyde on the radiation damage of liposomes

    International Nuclear Information System (INIS)

    Kuropteva, Z.V.; Sprinz, H.; Schaefer, H.; Winkler, E.

    1986-01-01

    By means of 1 H-NMR spectroscopy the influence of 5-nitro-2-furaldehyde (NF) on the permeation of Eu 3+ ions into irradiated liposomes of egg yolk lecithin was examined. In the presence of NF there was an increase in the permeability of irradiated liposomes. The damage of the liposomes was quantified spectrophotometrically in terms of diene conjugation. (author)

  8. Curcumin liposomes prepared with milk fat globule membrane phospholipids and soybean lecithin.

    Science.gov (United States)

    Jin, Hong-Hao; Lu, Qun; Jiang, Jian-Guo

    2016-03-01

    Using thin film ultrasonic dispersion method, the curcumin liposomes were prepared with milk fat globule membrane (MFGM) phospholipids and soybean lecithins, respectively, to compare the characteristics and stability of the 2 curcumin liposomes. The processing parameters of curcumin liposomes were investigated to evaluate their effects on the encapsulation efficiency. Curcumin liposomes were characterized in terms of size distribution, ζ-potential, and in vitro release behavior, and then their storage stability under various conditions was evaluated. The curcumin liposomes prepared with MFGM phospholipids had an encapsulation efficiency of about 74%, an average particle size of 212.3 nm, and a ζ-potential of -48.60 mV. The MFGM liposomes showed higher encapsulation efficiency, smaller particle size, higher absolute value of ζ-potential, and slower in vitro release than soybean liposomes. The retention rate of liposomal curcumin was significantly higher than that of free curcumin. The stability of the 2 liposomes under different pH was almost the same, but MFGM liposomes displayed a slightly higher stability than soybean liposomes under the conditions of Fe(3+), light, temperature, oxygen, and relative humidity. In conclusion, MFGM phospholipids have potential advantages in the manufacture of curcumin liposomes used in food systems. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. Pros and cons of the liposome platform in cancer drug targeting.

    Science.gov (United States)

    Gabizon, Alberto A; Shmeeda, Hilary; Zalipsky, Samuel

    2006-01-01

    Coating of liposomes with polyethylene-glycol (PEG) by incorporation in the liposome bilayer of PEG-derivatized lipids results in inhibition of liposome uptake by the reticulo-endothelial system and significant prolongation of liposome residence time in the blood stream. Parallel developments in drug loading technology have improved the efficiency and stability of drug entrapment in liposomes, particularly with regard to cationic amphiphiles such as anthracyclines. An example of this new generation of liposomes is a formulation of pegylated liposomal doxorubicin known as Doxil or Caelyx, whose clinical pharmacokinetic profile is characterized by slow plasma clearance and small volume of distribution. A hallmark of these long-circulating liposomal drug carriers is their enhanced accumulation in tumors. The mechanism underlying this passive targeting effect is the phenomenon known as enhanced permeability and retention (EPR) which has been described in a broad variety of experimental tumor types. Further to the passive targeting effect, the liposome drug delivery platform offers the possibility of grafting tumor-specific ligands on the liposome membrane for active targeting to tumor cells, and potentially intracellular drug delivery. The pros and cons of the liposome platform in cancer targeting are discussed vis-à-vis nontargeted drugs, using as an example a liposome drug delivery system targeted to the folate receptor.

  10. Interactions of liposome carriers with infectious fungal hyphae reveals the role of β-glucans.

    Science.gov (United States)

    Chavan, Neelam L; Young, Joseph K; Drezek, Rebekah A; Lewis, Russell; Bikram, Malavosklish

    2012-09-04

    Relatively little is known about how liposomal formulations modulate drug delivery to fungal pathogens. We compared patterns of hyphal cell wall binding for empty rhodmine-labeled liposomes and the clinically available amphotericin B-containing liposomal formulation (AmBisome) in Aspergillus fumigatus and Candida albicans. Following 0.5 h of coincubation with A. fumigatus , empty liposomes concentrated primarily in fungal septae along at the surface of the cell wall, suggesting that liposome uptake is concentrated in areas of the cell wall where linear glucan is exposed on the cell surface, which was confirmed by aniline blue staining. Consistent with this hypothesis, pretreatment of liposomes with soluble linear glucan (laminarin) decreased liposome binding in both Aspergillus and Candida fungal hyphae, while growth of Aspergillus hyphae in the presence of an agent that increases fungal cell wall surface exposure of linear β-glucans without cell death (caspofungin) increased liposome uptake throughout the Aspergillus fungal cell wall. Increasing the polyethylene glycol (PEG) concentration in liposomes from 0 to 30% significantly increased fungal uptake of liposomes that was only modestly attenuated when fungal cells were incubated in serum concentrations ranging from 10 to 100%. The presence of β-glucans on the fungal hyphae cell walls of Aspergillus fumigatus is one of the factors responsible for mediating the binding of liposome carriers to the hyphae and could explain possible synergy reported between liposomal amphotericin B and echinocanins.

  11. Determination of platinum drug release and liposome stability in human plasma by CE-ICP-MS

    DEFF Research Database (Denmark)

    Nguyen, Trinh Thi Nhu Tam; Ostergaard, Jesper; Stürup, Stefan

    2013-01-01

    An in vitro method for simultaneous assessment of platinum release and liposome stability of liposomal formulations in human plasma is demonstrated. The development and assessment of the method was performed on a PEGylated liposomal formulation containing cisplatin. Complete separation of free ci...

  12. Investigations of a new, highly negative liposome with improved biodistribution for imaging

    International Nuclear Information System (INIS)

    Hnatowich, D.J.; Clancy, B.

    1980-01-01

    An attractive feature of liposomes is the wide range of lipid composition that can lead to liposome formation, coupled with the observation that liposome biodistribution may be altered by varying lipid composition. For instance, adding charged lipids to neutral lecithin will alter the biodistribution of the resulting charged liposomes. We have prepared highly negative liposomes by replacing lecithin with negatively charged cardiolipin. The liposomes have been labeled in the lipid phase with Ga-67 and Tc-99m oxine and their properties evaluated. The expected high negative charge of the resulting liposomes was confirmed by an ion-exchange chromatographic technique. Using paper chromatography, the stability of the label was determined during incubation in saline and serum. Finally, biodistributions were determined at 2 h in mice, and the results compared with those for negative lecithin liposomes. Accumulated activities in liver and spleen were reduced by factors of five and 20, respectively, over lecithin liposomes. Since preferential accumulation of activity in these organs constitutes the biggest limitation to the use of lecithin liposomes, cardiolipin liposomes may prove to be more useful carriers of radioactivity in imaging applications. More importantly, however, these results illustrate the value of studying novel liposome types as potential radiopharmaceuticals

  13. Fluorescent cell-traceable dexamethasone-loaded liposomes for the treatment of inflammatory liver diseases

    NARCIS (Netherlands)

    Bartneck, M.; Scheyda, K.M.; Warzecha, K.T.; Rizzo, L.Y.; Hittatiya, K.; Luedde, T.; Storm, Gerrit; Trautwein, C.; Lammers, Twan Gerardus Gertudis Maria; Tacke, F.

    2015-01-01

    Liposomes are routinely used carrier materials for delivering drug molecules to pathological sites. Besides in tumors and inflammatory sites, liposomes also strongly accumulate in liver and spleen. The potential of using liposomes to treat acute and chronic liver disorders, however, has not yet been

  14. Fluorescent cell-traceable dexamethasone-loaded liposomes for the treatment of inflammatory liver diseases

    NARCIS (Netherlands)

    Bartneck, Matthias; Scheyda, Katharina M; Warzecha, Klaudia T; Rizzo, Larissa Y; Hittatiya, Kanishka; Luedde, Tom; Storm, G; Trautwein, Christian; Lammers, Twan; Tacke, Frank

    Liposomes are routinely used carrier materials for delivering drug molecules to pathological sites. Besides in tumors and inflammatory sites, liposomes also strongly accumulate in liver and spleen. The potential of using liposomes to treat acute and chronic liver disorders, however, has not yet been

  15. Improved permeability of acyclovir: optimization of mucoadhesive liposomes using the phospholipid vesicle-based permeation assay.

    Science.gov (United States)

    Naderkhani, Elenaz; Erber, Astrid; Škalko-Basnet, Nataša; Flaten, Gøril Eide

    2014-02-01

    The antiviral drug acyclovir (ACV) suffers from poor solubility both in lipophilic and hydrophilic environment, leading to low and highly variable bioavailability. To overcome these limitations, this study aimed at designing mucoadhesive ACV-containing liposomes to improve its permeability. Liposomes were prepared from egg phosphatidylcholine (E-PC) and E-PC/egg phosphatidylglycerol (E-PC/E-PG) and their surfaces coated with Carbopol. All liposomal formulations were fully characterized and for the first time the phospholipid vesicle-based permeation assay (PVPA) was used for testing in vitro permeability of drug from mucoadhesive liposome formulations. The negatively charged E-PC/E-PG liposomes could encapsulate more ACV than neutral E-PC liposomes. Coating with Carbopol increased the entrapment in the neutral E-PC liposomes. The incorporation of ACV into liposomes exhibited significant increase in its in vitro permeability, compared with its aqueous solution. The neutral E-PC liposomal formulations exhibited higher ACV permeability values compared with charged E-PC/E-PG formulations. Coating with Carbopol significantly enhanced the permeability from the E-PC/E-PG liposomes, as well as sonicated E-PC liposomes, which showed the highest permeability of all tested formulations. The increased permeability was according to the formulations' mucoadhesive properties. This indicates that the PVPA is suitable to distinguish between permeability of ACV from different mucoadhesive liposome formulations developed for various routes of administration. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  16. Liposomal bupivacaine: a review of a new bupivacaine formulation

    Directory of Open Access Journals (Sweden)

    Chahar P

    2012-08-01

    Full Text Available Praveen Chahar, Kenneth C Cummings IIIAnesthesiology Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USAAbstract: Many attempts have been made to increase the duration of local anesthetic action. One avenue of investigation has focused on encapsulating local anesthetics within carrier molecules to increase their residence time at the site of action. This article aims to review the literature surrounding the recently approved formulation of bupivacaine, which consists of bupivacaine loaded in multivesicular liposomes. This preparation increases the duration of local anesthetic action by slow release from the liposome and delays the peak plasma concentration when compared to plain bupivacaine administration. Liposomal bupivacaine has been approved by the US Food and Drug Administration for local infiltration for pain relief after bunionectomy and hemorrhoidectomy. Studies have shown it to be an effective tool for postoperative pain relief with opioid sparing effects and it has also been found to have an acceptable adverse effect profile. Its kinetics are favorable even in patients with moderate hepatic impairment, and it has been found not to delay wound healing after orthopedic surgery. More studies are needed to establish its safety and efficacy for use via intrathecal, epidural, or perineural routes. In conclusion, liposomal bupivacaine is effective for treating postoperative pain when used via local infiltration when compared to placebo with a prolonged duration of action, predictable kinetics, and an acceptable side effect profile. However, more adequately powered trials are needed to establish its superiority over plain bupivacaine.Keywords: liposomal bupivacaine, postoperative pain, pharmacokinetics, pharmacodynamics, efficacy, safety

  17. Preparation and characterization of clove essential oil-loaded liposomes.

    Science.gov (United States)

    Sebaaly, Carine; Jraij, Alia; Fessi, Hatem; Charcosset, Catherine; Greige-Gerges, Hélène

    2015-07-01

    In this study, suitable formulations of natural soybean phospholipid vesicles were developed to improve the stability of clove essential oil and its main component, eugenol. Using an ethanol injection method, saturated (Phospholipon 80H, Phospholipon 90H) and unsaturated soybean (Lipoid S100) phospholipids, in combination with cholesterol, were used to prepare liposomes at various eugenol and clove essential oil concentrations. Liposomal batches were characterized and compared for their size, polydispersity index, Zeta potential, loading rate, encapsulation efficiency and morphology. The liposomes were tested for their stability after storing them for 2 months at 4°C by monitoring changes in their mean size, polydispersity index and encapsulation efficiency (EE) values. It was found that liposomes exhibited nanometric oligolamellar and spherical shaped vesicles and protected eugenol from degradation induced by UV exposure; they also maintained the DPPH-scavenging activity of free eugenol. Liposomes constitute a suitable system for encapsulation of volatile unstable essential oil constituents. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Application of Liposomes in Treatment of Rheumatoid Arthritis: Quo Vadis

    Directory of Open Access Journals (Sweden)

    Bhupinder Kapoor

    2014-01-01

    Full Text Available The most common treatments for rheumatoid arthritis include nonsteroidal anti-inflammatory drugs (NSAIDs, corticosteroids, disease modifying antirheumatic drugs (DMARDs, and some biological agents. However, none of the treatments available is able to achieve the ultimate goal of treatment, that is, drug-free remission. This limitation has shifted the focus of treatment to delivery strategies with an ability to deliver the drugs into the synovial cavity in the proper dosage while mitigating side effects to other tissues. A number of approaches like microemulsions, microspheres, liposomes, microballoons, cocrystals, nanoemulsions, dendrimers, microsponges, and so forth, have been used for intrasynovial delivery of these drugs. Amongst these, liposomes have proven to be very effective for retaining the drug in the synovial cavity by virtue of their size and chemical composition. The fast clearance of intra-synovially administered drugs can be overcome by use of liposomes leading to increased uptake of drugs by the target synovial cells, which in turn reduces the exposure of nontarget sites and eliminates most of the undesirable effects associated with therapy. This review focuses on the use of liposomes in treatment of rheumatoid arthritis and summarizes data relating to the liposome formulations of various drugs. It also discusses emerging trends of this promising technology.

  19. Stimuli-responsive Smart Liposomes in Cancer Targeting.

    Science.gov (United States)

    Jain, Ankit; Jain, Sanjay K

    2018-02-08

    Liposomes are vesicular carriers which possess aqueous core entrapped within the lipid bilayer. These are carriers of choice because of biocompatible and biodegradable features in addition to flexibility of surface modifications at surface and lipid compositions of lipid bilayers. Liposomes have been reported well for cancer treatment using both passive and active targeting approaches however tumor microenvironment is still the biggest hurdle for safe and effective delivery of anticancer agents. To overcome this problem, stimuli-responsive smart liposomes have emerged as promising cargoes pioneered to anomalous tumor milieu in response to pH, temperature, and enzymes etc. as internal triggers, and magnetic field, ultrasound, and redox potential as external guides for enhancement of drug delivery to tumors. This review focuses on all such stimuli-responsive approaches using fabrication potentiality of liposomes in combination to various ligands, linkers, and PEGylation etc. Scientists engaged in cancer targeting approaches can get benefited greatly with this knowledgeable assemblage of advances in liposomal nanovectors. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  20. Liposome Disruption Assay to Examine Lytic Properties of Biomolecules.

    Science.gov (United States)

    Jimah, John R; Schlesinger, Paul H; Tolia, Niraj H

    2017-08-05

    Proteins may have three dimensional structural or amino acid features that suggest a role in targeting and disrupting lipids within cell membranes. It is often necessary to experimentally investigate if these proteins and biomolecules are able to disrupt membranes in order to conclusively characterize the function of these biomolecules. Here, we describe an in vitro assay to evaluate the membrane lytic properties of proteins and biomolecules. Large unilamellar vesicles (liposomes) containing carboxyfluorescein at fluorescence-quenching concentrations are treated with the biomolecule of interest. A resulting increase in fluorescence due to leakage of the dye from liposomes and subsequent dilution in the buffer demonstrates that the biomolecule is sufficient for disrupting liposomes and membranes. Additionally, since liposome disruption may occur via pore-formation or via general solubilization of lipids similar to detergents, we provide a method to distinguish between these two mechanisms. Pore-formation can be identified and evaluated by examining the blockade of carboxyfluorescein release with dextran molecules that fit the pore. The methods described here were used to determine that the malaria vaccine candidate CelTOS and proapoptotic Bax disrupt liposomes by pore formation (Saito et al. , 2000; Jimah et al. , 2016). Since membrane lipid binding by a biomolecule precedes membrane disruption, we recommend the companion protocol: Jimah et al. , 2017.

  1. Biophysical aspects of using liposomes as delivery vehicles.

    Science.gov (United States)

    Ulrich, Anne S

    2002-04-01

    Liposomes are used as biocompatible carriers of drugs, peptides, proteins, plasmic DNA, antisense oligonucleotides or ribozymes, for pharmaceutical, cosmetic, and biochemical purposes. The enormous versatility in particle size and in the physical parameters of the lipids affords an attractive potential for constructing tailor-made vehicles for a wide range of applications. Some of the recent literature will be reviewed here and presented from a biophysical point of view, thus providing a background for the more specialized articles in this special issue on liposome technology. Different properties (size, colloidal behavior, phase transitions, and polymorphism) of diverse lipid formulations (liposomes, lipoplexes, cubic phases, emulsions, and solid lipid nanoparticles) for distinct applications (parenteral, transdermal, pulmonary, and oral administration) will be rationalized in terms of common structural, thermodynamic and kinetic parameters of the lipids. This general biophysical basis helps to understand pharmaceutically relevant aspects such as liposome stability during storage and towards serum, the biodistribution and specific targeting of cargo, and how to trigger drug release and membrane fusion. Methods for the preparation and characterization of liposomal formulations in vitro will be outlined, too.

  2. Liposomes self-assembled from electrosprayed composite microparticles

    International Nuclear Information System (INIS)

    Yu Dengguang; Yang Junhe; Wang Xia; Tian Feng

    2012-01-01

    Composite microparticles, consisting of polyvinylpyrrolidone (PVP), naproxen (NAP) and lecithin (PC), have been successfully prepared using an electrospraying process and exploited as templates to manipulate molecular self-assembly for the synthesis of liposomes in situ. Field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM) observations demonstrate that the microparticles have an average diameter of 960 ± 140 nm and a homogeneous structure. X-ray diffraction (XRD) patterns, differential scanning calorimetry (DSC) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) results verify that the building blocks NAP and PC are scattered in the polymer matrix in a molecular way owing to the very fast drying of the electrospraying process and the favorable secondary interactions among the components. FESEM, scanning probe microscope (SPM) and TEM observations demonstrate that the liposomes can be achieved through molecular self-assembly in situ when the microparticles contact water thanks to ‘like prefers like’ and by means of the confinement effect of the microparticles. The liposomes have an encapsulation rate of 91.3%, and 80.7% of the drug in the liposomes can be freed into the dissolution medium in a sustained way and by a diffusion mechanism over a period of 24 h. The developed strategy not only provides a new, facile, and effective method to assemble and organize molecules of multiple components into liposomes with electrosprayed microparticles as templates, but also opens a new avenue for nanofabrication in a step-by-step and controllable way. (paper)

  3. Benchmarking of Sterilizing grade filters with liposome Filtration.

    Science.gov (United States)

    Loewe, Thomas; Mundlamuri, Ramesh; Loewe, Thomas; Mundrigi, Ashok; Handt, Sebastian; Singh, Bhuwan

    2017-12-14

    Cytotoxic drugs can be encapsulated in liposomes vesicles, which act as drug delivery vehicles and reduce the risk of exposure of drug to healthy cells(1). The sterility of such liposome solutions is typically ensured using 0.2μm rated sterilizing grade membranes, but due to the high viscosity and low surface tension of these formulations, they can cause pre-mature blocking and increased risk of bacterial penetration through a 0.2μm sterilizing grade membrane(2). The low surface tension of liposome solutions affects the contact angle with membrane and reduces bubble point leading to bacterial penetration through the membrane. This poses a great challenge to select an appropriate sterilizing grade membrane for a given process and for filter manufacturers to develop a sterilizing grade membrane that specifically addresses these needs. In this study, the influence of different variables that could affect the total throughput and bacterial retention performance of different membranes types on processing of liposome solutions have been evaluated. Based on the results, we conclude that the membrane properties e.g., surface porosity, surface tension, pore size, symmetry/asymmetry, hydrophilicity and liposome properties e.g., composition, lipid size and concentration affect bacterial retention and total throughput capacity. Process parameters such as temperature, pressure and flow should also be optimized to improve process efficiency. Copyright © 2017, Parenteral Drug Association.

  4. Multivesicular liposomal bupivacaine at the sciatic nerve

    Science.gov (United States)

    McAlvin, J. Brian; Padera, Robert F.; Shankarappa, Sahadev A.; Reznor, Gally; Kwon, Albert H.; Chiang, Homer; Yang, Jason; Kohane, Daniel S.

    2014-01-01

    Clinical translation of sustained release formulations for local anesthetics has been limited by adverse tissue reaction. Exparel™ (DepoFoam bupivacaine) is a new liposomal local anesthetic formulation whose biocompatibility near nerve tissue is not well characterized. Exparel™ injection caused sciatic nerve blockade in rats lasting 240 minutes compared to 120 minutes for 0.5% (w/v) bupivacaine HCl and 210 minutes for 1.31% (w/v) bupivacaine HCl (same bupivacaine content as Exparel™). On histologic sections four days after injection, median inflammation scores in the Exparel™ group (2.5 of 4) were slightly higher than in groups treated with bupivacaine solutions (score 2). Myotoxicity scores in the Exparel™ group (2.5 of 6) were similar to in the 0.5% (w/v) bupivacaine HCl group (3), but significantly less than in the 1.31% (w/v) bupivacaine HCl group (5). After two weeks, inflammation from Exparel™ (score 2 of 6) was greater than from 0.5% (w/v) bupivacaine HCl (1) and similar to that from 1.31% (w/v) bupivacaine HCl (1). Myotoxicity in all three groups was not statistically significantly different. No neurotoxicity was detected in any group. Tissue reaction to Exparel™ was similar to that of 0.5% (w/v) bupivacaine HCl. Surveillance for local tissue injury will be important during future clinical evaluation. PMID:24612918

  5. Construction of a Liposome Dialyzer for preparation of high-value, small-volume liposome formulations

    Science.gov (United States)

    Adamala, Katarzyna; Engelhart, Aaron E.; Kamat, Neha P.; Jin, Lin; Szostak, Jack W.

    2016-01-01

    The liposome dialyzer is a small-volume equilibrium dialysis device, built from commercially available materials, that is designed for rapid exchange of small volumes of an extraliposomal reagent pool against a liposome preparation. The dialyzer is prepared by modification of commercially available dialysis cartridges and consists of a reactor with two 300 µL chambers and a 1.56 cm2 dialysis surface area. The dialyzer is prepared in three stages: 1) disassembly of dialysis cartridges to obtain required parts; 2) assembly of the dialyzer; and 3) sealing the dialyzer with epoxy. Preparation of the dialyser takes about 1.5 h, not including overnight epoxy curing. Each round of dialysis takes 1–24 h, depending on the analyte and membrane employed. We previously used the dialyzer for small-volume nonenzymatic RNA synthesis reactions inside fatty acid vesicles. In this protocol, we demonstrate other applications, including removal of unencapsulated calcein from vesicles, remote loading, and vesicle microscopy. PMID:26020615

  6. Binding of human serum albumin to PEGylated liposomes: insights into binding numbers and dynamics by fluorescence correlation spectroscopy

    DEFF Research Database (Denmark)

    Kristensen, Kasper; Urquhart, Andrew; Thormann, Esben

    2016-01-01

    Liposomes for medical applications are often administered by intravenous injection. Once in the bloodstream, the liposomes are covered with a "protein corona", which impacts the behavior and eventual fate of the liposomes. Currently, many aspects of the liposomal protein corona are not well...

  7. Potential of Continuous Manufacturing for Liposomal Drug Products.

    Science.gov (United States)

    Worsham, Robert D; Thomas, Vaughan; Farid, Suzanne S

    2018-05-21

    Over the last several years, continuous manufacturing of pharmaceuticals has evolved from bulk APIs and solid oral dosages into the more complex realm of biologics. The development of continuous downstream processing techniques has allowed biologics manufacturing to realize the benefits (e.g. improved economics, more consistent quality) that come with continuous processing. If relevant processing techniques and principles are selected, the opportunity arises to develop continuous manufacturing designs for additional pharmaceutical products including liposomal drug formulations. Liposome manufacturing has some inherent aspects that make it favorable for a continuous process. Other aspects such as formulation refinement, materials of construction, and aseptic processing need development, but present an achievable challenge. This paper reviews the current state of continuous manufacturing technology applicable to liposomal drug product manufacturing and an assessment of the challenges and potential of this application. This article is protected by copyright. All rights reserved.

  8. Lipophilic drug transfer between liposomal and biological membranes

    DEFF Research Database (Denmark)

    Fahr, Alfred; van Hoogevest, Peter; Kuntsche, Judith

    2006-01-01

    This review presents the current knowledge on the interaction of lipophilic, poorly water soluble drugs with liposomal and biological membranes. The center of attention will be on drugs having the potential to dissolve in a lipid membrane without perturbing them too much. The degree of interaction...... is described as solubility of a drug in phospholipid membranes and the kinetics of transfer of a lipophilic drug between membranes. Finally, the consequences of these two factors on the design of lipid-based carriers for oral, as well as parenteral use, for lipophilic drugs and lead selection of oral...... lipophilic drugs is described. Since liposomes serve as model-membranes for natural membranes, the assessment of lipid solubility and transfer kinetics of lipophilic drug using liposome formulations may additionally have predictive value for bioavailability and biodistribution and the pharmacokinetics...

  9. Radiolabeling of liposomes and polymeric micelles with PET-isotopes

    DEFF Research Database (Denmark)

    Jensen, Andreas Tue Ingemann

    as a revolution in modern therapeutics, especially in chemotherapy. A major reason is the ability of nanoparticles to accumulate in tumor tissue. Liposomes are the classic nanoparticle, consisting of a lipid membrane with an aqueous core. Polymeric micelles are made from amphiphilic detergent‐like copolymers......This thesis is divided into three separate chapters that can be read independently. Chapter 1 is a general introduction, touching upon liposomes and polymeric micelles and radiolabeling with 18F and 64Cu. Chapter 2 and 3 address two separate research projects, each described below. A complete......‐life only allowing up to 8 hours scans. 18F must be covalently attached to components of the liposome. By binding to a lipid, it can be stably lodged in the membrane. A glycerolipid and a cholesteryl ether were synthesized with free primary alcohols and a series of their sulphonates (Ms, Ts, Tf) were...

  10. Ultraviolet- and sunlight-induced lipid peroxidation in liposomal membrane

    International Nuclear Information System (INIS)

    Mandal, T.K.; Chatterjee, S.N.

    1980-01-01

    Ultraviolet radiation and sunlight caused lipid peroxidation in the liposomal membrane (as detected by measurement of the oxidation index, A 233 /A 215 , and the amount of malondialdehyde formed) and made the membrane leaky (as revealed by the release of the trapped chromate anions). The oxidation index and the formation of malondialdehyde increased linearly with increasing dose of radiation and depended significantly on the dose rate. The effects were smaller in liposomes derived from Vibrio cholerae phospholipid than in those derived from egg lecithin. The effects of the radiation dose and dose rate on hemolysis and peroxidation (MDA formation) of the erythrocyte membrane followed a similar pattern. A direct correlation between the percentage leakage of chromate (Y) and the oxidation index (X) of the liposomal system was obtained as Y = 236.5 x X

  11. Assembly of Liposomes Controlled by Triple Helix Formation

    DEFF Research Database (Denmark)

    Vogel, Stefan; Jakobsen, Ulla

    2013-01-01

    Attachment of DNA to the surface of different solid nanoparticles (e.g. gold- and silica nanoparticles) is well established and a number of DNA-modified solid nanoparticle systems have been applied to thermal denaturation analysis of oligonucleotides. We report herein the non-covalent immobilizat...... analysis (NTA) and dynamic light scattering (DLS) show independently from ultraviolet spectroscopy experiments the formation of liposome aggregates.......-covalent immobilization of oligonucleotides on the surface of soft nanoparticles (e.g. liposomes) and the subsequent controlled assembly by DNA triple helix formation. The non-covalent approach avoids tedious surface chemistry and necessary purification procedures and can simplify and extend the available methodology...... sequences (G or C-rich) to explore the applicability of the method for different triple helical assembly modes. We demonstrate advantages and limitations of the approach and proof the reversible and reproducible formation of liposome aggregates during thermal denaturation cycles. Nanoparticle tracking...

  12. Recent Trends in Multifunctional Liposomal Nanocarriers for Enhanced Tumor Targeting

    Directory of Open Access Journals (Sweden)

    Federico Perche

    2013-01-01

    Full Text Available Liposomes are delivery systems that have been used to formulate a vast variety of therapeutic and imaging agents for the past several decades. They have significant advantages over their free forms in terms of pharmacokinetics, sensitivity for cancer diagnosis and therapeutic efficacy. The multifactorial nature of cancer and the complex physiology of the tumor microenvironment require the development of multifunctional nanocarriers. Multifunctional liposomal nanocarriers should combine long blood circulation to improve pharmacokinetics of the loaded agent and selective distribution to the tumor lesion relative to healthy tissues, remote-controlled or tumor stimuli-sensitive extravasation from blood at the tumor’s vicinity, internalization motifs to move from tumor bounds and/or tumor intercellular space to the cytoplasm of cancer cells for effective tumor cell killing. This review will focus on current strategies used for cancer detection and therapy using liposomes with special attention to combination therapies.

  13. Exchangeable pulmonary water space evaluation using giant liposomes

    International Nuclear Information System (INIS)

    Santos, A.C.; Ribeiro, M.J.; Ferreira, N.; De Lima, J.J.P.

    1998-01-01

    The present work aims to study the potential use of liposomes for the evaluation of pulmonary exchangeable water space, important parameter in some pulmonary oedema situations. This study is based upon the delivery of a diffusible water radiotracer into pulmonary capillary network, which equilibrates with interstitial water space of the lung and returns to the blood circulation. The time constant of this phenomena depends on the magnitude of the water space under study. The release of the diffusible radiotracer in lung capillaries is performed using liposomes with specific formulation. The giant liposomes (15-30μm diameter) used in this study are instable at 37 deg. C. They are biocompatible, biodegradable, with low toxicity and showed no immunogenicity. A water tracer labelled with 99m Tc, encapsulated in the aqueous phase of giant liposomes, has been used. Liposomes were prepared in sterile conditions and with apyrogenic materials. The lipid films composition is L-α-diestearoylphosphatidylcholine (DSPC), L-α-phosphatidyl-DL-glycerol (EPG) and cholesterol (CHOL) (60%/10%/30% mass ratio). After iv injection at +-20 deg. C in the femoral vein of Wistar rats (300g-600g) or albine rabbits (4.5-5Kg), the thermolabile liposomes will be entrapped in lung capillaries and release the radiotracer locally. When the radiodrug is diffusible we will evaluate the volume of the exchangeable pulmonary water analyzing the activity/time curves. These curves are slower for greater water spaces. When the radiotracer is non-diffusible, the disappearance curves are not influenced by the extravascular water space. (author)

  14. Thermosensitive liposomal drug delivery systems: state of the art review

    Directory of Open Access Journals (Sweden)

    Kneidl B

    2014-09-01

    Full Text Available Barbara Kneidl,1,2 Michael Peller,3 Gerhard Winter,2 Lars H Lindner,1 Martin Hossann11Department of Internal Medicine III, University Hospital Munich, 2Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, 3Institute for Clinical Radiology, University Hospital Munich, Ludwig-Maximilians University, Munich, GermanyAbstract: Thermosensitive liposomes are a promising tool for external targeting of drugs to solid tumors when used in combination with local hyperthermia or high intensity focused ultrasound. In vivo results have demonstrated strong evidence that external targeting is superior over passive targeting achieved by highly stable long-circulating drug formulations like PEGylated liposomal doxorubicin. Up to March 2014, the Web of Science listed 371 original papers in this field, with 45 in 2013 alone. Several formulations have been developed since 1978, with lysolipid-containing, low temperature-sensitive liposomes currently under clinical investigation. This review summarizes the historical development and effects of particular phospholipids and surfactants on the biophysical properties and in vivo efficacy of thermosensitive liposome formulations. Further, treatment strategies for solid tumors are discussed. Here we focus on temperature-triggered intravascular and interstitial drug release. Drug delivery guided by magnetic resonance imaging further adds the possibility of performing online monitoring of a heating focus to calculate locally released drug concentrations and to externally control drug release by steering the heating volume and power. The combination of external targeting with thermosensitive liposomes and magnetic resonance-guided drug delivery will be the unique characteristic of this nanotechnology approach in medicine.Keywords: thermosensitive liposomes, phosphatidyloligoglycerol, hyperthermia, high intensity focused ultrasound, drug delivery, drug targeting

  15. PEG minocycline-liposomes ameliorate CNS autoimmune disease.

    Directory of Open Access Journals (Sweden)

    Wei Hu

    Full Text Available Minocycline is an oral tetracycline derivative with good bioavailability in the central nervous system (CNS. Minocycline, a potent inhibitor of matrix metalloproteinase (MMP-9, attenuates disease activity in experimental autoimmune encephalomyelitis (EAE, an animal model of multiple sclerosis (MS. Potential adverse effects associated with long-term daily minocycline therapy in human patients are concerning. Here, we investigated whether less frequent treatment with long-circulating polyethylene glycol (PEG minocycline liposomes are effective in treating EAE.Performing in vitro time kinetic studies of PEG minocycline-liposomes in human peripheral blood mononuclear cells (PBMCs, we determined that PEG minocycline-liposome preparations stabilized with CaCl(2 are effective in diminishing MMP-9 activity. Intravenous injections of PEG minocycline-liposomes every five days were as effective in ameliorating clinical EAE as daily intraperitoneal injections of minocycline. Treatment of animals with PEG minocycline-liposomes significantly reduced the number of CNS-infiltrating leukocytes, and the overall expression of MMP-9 in the CNS. There was also a significant suppression of MMP-9 expression and proteolytic activity in splenocytes of treated animals, but not in CNS-infiltrating leukocytes. Thus, leukocytes gaining access to the brain and spinal cord require the same absolute amount of MMP-9 in all treatment groups, but minocycline decreases the absolute cell number.Our data indicate that less frequent injections of PEG minocycline-liposomes are an effective alternative pharmacotherapy to daily minocycline injections for the treatment of CNS autoimmune diseases. Also, inhibition of MMP-9 remains a promising treatment target in EAE and patients with MS.

  16. Multifunctional quantum dots and liposome complexes in drug delivery

    Science.gov (United States)

    Wang, Qi; Chao, Yimin

    2018-01-01

    Incorporating both diagnostic and therapeutic functions into a single nanoscale system is an effective modern drug delivery strategy. Combining liposomes with semiconductor quantum dots (QDs) has great potential to achieve such dual functions, referred to in this review as a liposomal QD hybrid system (L-QD). Here we review the recent literature dealing with the design and application of L-QD for advances in bio-imaging and drug delivery. After a summary of L-QD synthesis processes and evaluation of their properties, we will focus on their multifunctional applications, ranging from in vitro cell imaging to theranostic drug delivery approaches. PMID:28866655

  17. Multifunctional quantum dots and liposome complexes in drug delivery.

    Science.gov (United States)

    Wang, Qi; Chao, Yi-Min

    2017-09-03

    Incorporating both diagnostic and therapeutic functions into a single nanoscale system is an effective modern drug delivery strategy. Combining liposomes with semiconductor quantum dots (QDs) has great potential to achieve such dual functions, referred to in this review as a liposomal QD hybrid system (L-QD). Here we review the recent literature dealing with the design and application of L-QD for advances in bio-imaging and drug delivery. After a summary of L-QD synthesis processes and evaluation of their properties, we will focus on their multifunctional applications, ranging from in vitro cell imaging to theranostic drug delivery approaches.

  18. Acute Pancreatitis by liposomal amphotericin B.

    Directory of Open Access Journals (Sweden)

    Rafael Hernández

    2016-11-01

    Full Text Available BACKGROUND: The most frequently observed adverse reactions of a liposomal formulation of amphotericin B (LAB on the first dose of fever and rigors are, hypokalemia and renal toxicity. Acute pancreatitis is not listed in the Summary of Product Characteristics of LAB, although some non-severe cases of pancreatitis toxicity after LAB are described in the literature. CASE SUMMARY: We present the case of an 88-year-old male with not known allergies and diagnosed with arterial hypertension and Grade III chronic kidney disease. One month before was admitted because of pneumonia, acute kidney injury, atrial fibrillation and pancytopenia; he was discharged on January 13, 2016, and two weeks later, he returned to the Urgency Department with severe deterioration of the general condition, fever, and a skin rash , these symptoms were attributed to a delayed allergic reaction to levofloxacin. During his first admission, he was treated with acetylsalicylic acid 100 mg, digoxin, metamizole, pantoprazole, valsartan/amlodipine. The Lab results showed pancytopenia. It was performed a bone marrow aspiration, suggesting a case of leishmaniasis. It was initiated intravenous treatment with LAB at 3 mg / kg / day. The first day of treatment, the patient showed a severe bronchospasm, exacerbation of the previous rash possibly caused by quinolones treatment, was treated with corticosteroids, antihistamines, aerosol therapy and oxygen therapy until full recovery. During the following days, LAB was administrated at a slow infusion rate and premedication with appropriate tolerance. On the fifth day of the treatment, the patient started with a diffuse abdominal pain, anorexia, and vomiting. The amylase lab result was 431 IU/L. An abdominal scanner showed edematous pancreatitis. After 48 hours the amylase and lipase lab values were normal. And the abdominal Scanner was repeated with no changes. The evolution of patient was aggravating until reaching multiple organs failure a

  19. Bleomycin-Loaded pH-Sensitive Polymer–Lipid-Incorporated Liposomes for Cancer Chemotherapy

    Directory of Open Access Journals (Sweden)

    Eiji Yuba

    2018-01-01

    Full Text Available Cancer chemotherapeutic systems with high antitumor effects and less adverse effects are eagerly desired. Here, a pH-sensitive delivery system for bleomycin (BLM was developed using egg yolk phosphatidylcholine liposomes modified with poly(ethylene glycol-lipid (PEG-PE for long circulation in the bloodstream and 2-carboxycyclohexane-1-carboxylated polyglycidol-having distearoyl phosphatidylethanolamine (CHexPG-PE for pH sensitization. The PEG-PE/CHexPG-PE-introduced liposomes showed content release responding to pH decrease and were taken up by tumor cells at a rate 2.5 times higher than that of liposomes without CHexPG-PE. BLM-loaded PEG-PE/CHexPG-PE-introduced liposomes exhibited comparable cytotoxicity with that of the free drug. Intravenous administration of these liposomes suppressed tumor growth more effectively in tumor-bearing mice than did the free drug and liposomes without CHexPG-PE. However, at a high dosage of BLM, these liposomes showed severe toxicity to the spleen, liver, and lungs, indicating the trapping of liposomes by mononuclear phagocyte systems, probably because of recognition of the carboxylates on the liposomes. An increase in PEG molecular weight on the liposome surface significantly decreased toxicity to the liver and spleen, although toxicity to the lungs remained. Further improvements such as the optimization of PEG density and lipid composition and the introduction of targeting ligands to the liposomes are required to increase therapeutic effects and to reduce adverse effects.

  20. Fundamentals of ionic conductivity relaxation gained from study of procaine hydrochloride and procainamide hydrochloride at ambient and elevated pressure.

    Science.gov (United States)

    Wojnarowska, Z; Swiety-Pospiech, A; Grzybowska, K; Hawelek, L; Paluch, M; Ngai, K L

    2012-04-28

    The pharmaceuticals, procaine hydrochloride and procainamide hydrochloride, are glass-forming as well as ionically conducting materials. We have made dielectric measurements at ambient and elevated pressures to characterize the dynamics of the ion conductivity relaxation in these pharmaceuticals, and calorimetric measurements for the structural relaxation. Perhaps due to their special chemical and physical structures, novel features are found in the ionic conductivity relaxation of these pharmaceuticals. Data of conductivity relaxation in most ionic conductors when represented by the electric loss modulus usually show a single resolved peak in the electric modulus loss M(")(f) spectra. However, in procaine hydrochloride and procainamide hydrochloride we find in addition another resolved loss peak at higher frequencies over a temperature range spanning across T(g). The situation is analogous to many non-ionic glass-formers showing the presence of the structural α-relaxation together with the Johari-Goldstein (JG) β-relaxation. Naturally the analogy leads us to name the slower and faster processes resolved in procaine hydrochloride and procainamide hydrochloride as the primary α-conductivity relaxation and the secondary β-conductivity relaxation, respectively. The analogy of the β-conductivity relaxation in procaine HCl and procainamide HCl with JG β-relaxation in non-ionic glass-formers goes further by the finding that the β-conductivity is strongly related to the α-conductivity relaxation at temperatures above and below T(g). At elevated pressure but compensated by raising temperature to maintain α-conductivity relaxation time constant, the data show invariance of the ratio between the β- and the α-conductivity relaxation times to changes of thermodynamic condition. This property indicates that the β-conductivity relaxation has fundamental importance and is indispensable as the precursor of the α-conductivity relaxation, analogous to the relation found

  1. Visualization of liposomes by magnetic resonance imaging: an opportunity to improve antitumoral liposome therapies

    International Nuclear Information System (INIS)

    Martinez Bedoya, Darel

    2012-01-01

    Controlled release of drugs at the tumor site and the development of non-invasive monitoring techniques are two of the main challenges currently facing antitumoral therapies. The paper analyzes some of the potential uses of liposomes as vehicles for the transport of drugs to the tumors, particularly directionalized variants to tumor antigens through antibody coupling (immunoliposomes). These vesicles may also be used in combination with magnetic resonance, one of the most widely used imaging techniques, and one exhibiting great visualization potential at molecular level. Joint use of these two techniques makes it possible to control the amount of drug administered, as well as predict the efficacy of the treatment and monitor its progress

  2. Adsorption of dodecylamine hydrochloride on graphene oxide in water

    Directory of Open Access Journals (Sweden)

    Peng Chen

    Full Text Available Cationic surfactants in water are difficult to be degraded, leading to serious water pollution. In this work, graphene oxide (GO was used as an adsorbent for removing Dodecylamine Hydrochloride (DACl, a representative cationic surfactant. X-ray diffraction (XRD, FT-IR spectroscopy and atomic force microscope (AFM were used to characterize the prepared GO. The adsorption of DACl on GO have been investigated through measurements of adsorption capacity, zeta potential, FTIR, and X-ray photoelectron spectroscopy (XPS. The experimental results have shown that the adsorption kinetics could be described as a rate-limiting pseudo second-order process, and the adsorption isotherm agreed well with the Freundlich model. GO was a good adsorbent for DACl removal, compared with coal fly ash and powdered activated carbon. The adsorption process was endothermic, and could be attributed to electrostatic interaction and hydrogen bonding between DACl and GO. Keywords: Graphene oxide, Dodecylamine hydrochloride, Adsorption isotherm, Adsorption mechanisms

  3. Disposable screen-printed sensors for determination of duloxetine hydrochloride

    Directory of Open Access Journals (Sweden)

    Alarfaj Nawal A

    2012-01-01

    Full Text Available Abstract A screen-printed disposable electrode system for the determination of duloxetine hydrochloride (DL was developed using screen-printing technology. Homemade printing has been characterized and optimized on the basis of effects of the modifier and plasticizers. The fabricated bi-electrode potentiometric strip containing both working and reference electrodes was used as duloxetine hydrochloride sensor. The proposed sensors worked satisfactorily in the concentration range from 1.0 × 10-6-1.0 × 10-2 mol L-1 with detection limit reaching 5.0 × 10-7 mol L-1 and adequate shelf life of 6 months. The method is accurate, precise and economical. The proposed method has been applied successfully for the analysis of the drug in pure and in its dosage forms. In this method, there is no interference from any common pharmaceutical additives and diluents. Results of the analysis were validated statistically by recovery studies.

  4. Chemoreactomic analysis of thiamine disulfide, thiamine hydrochloride, and benfotiamine molecules

    OpenAIRE

    O. A. Gromova; I. Yu. Torshin; L. V. Stakhovskaya; L. E. Fedotova

    2017-01-01

    Objective: to analyze the interactions that could indicate the potential pharmacological properties of the molecules of thiamin, thiamine disulfide, and others.Material and methods. The investigators simulated the properties of thiamine disulfide (bistiamin) versus those of the reference molecules of thiamin hydrochloride and benfotiamine. The study was performed using chemoreactomic simulation that is the newest area in post-genome pharmacology.Results and discussion. Chemoreactomic analysis...

  5. Microparticulate drug delivery system containing tramadol hydrochloride for pain treatment.

    Science.gov (United States)

    Ciurba, Adriana; Todoran, Nicoleta; Vari, C E; Lazăr, Luminita; Al Hussein, Stela; Hancu, G

    2014-01-01

    The current trend of replacing conventional pharmaceutical forms is justified because most substances administered in this form give fluctuations of therapeutic concentrations and often outside the therapeutic range. In addition, these formulations offer a reduction in the dose or the number of administrations, thus increasing patient compliance. In the experiment, we developed an appropriate technology for the preparation of gelatin microspheres containing tramadol hydrochloride by emulsification/cross-linking method. The formulated microspheres were characterized by product yield, size distribution, encapsulation efficiency and in vitro release of tramadol hydrochloride. Data obtained from in vitro release studies were fitted to various mathematical models to elucidate the transport mechanisms. The kinetic models used were zero-order, first-order, Higuchi Korsmeyer-Peppas and Hopfenberg. Spherical microspheres were obtained, with free-flowing properties. The entrapment efficiency of tramadol hydrochloride in microparticles was 79.91% and product yield -94.92%. As the microsphere size was increased, the entrapment efficiency increased. This was 67.56, 70.03, 79.91% for formulations MT80-250, MT8-500 and, MT250-500. High entrapment efficiency was observed for MT250-500 formulation. The gelatin microspheres had particle sizes ranging from 80 to 500 microm. The drug was released for a period of 12 hours with a maximum release of 96.02%. Of the three proposed formulations, MT250-500 presented desirable properties and optimal characteristics for the therapy of pain. Release of tramadol hydrochloridi was best fitted to Korsmeyer-Peppas equation because the Akaike Information Criterion had the lowest values for this kinetic model. These results suggest the opportunity to influence the therapeutic characteristics of gelatin microspheres to obtain a suitable drug delivery system for the oral administration of tramadol hydrochloride.

  6. Enantiospecific synthesis of (1- sup 3 H)-(+)-pseudoephedrine hydrochloride

    Energy Technology Data Exchange (ETDEWEB)

    Hill, J.A.; Scharver, J.D. (Burroughs Wellcome Co., Research Triangle Park, North Carolina (USA). Chemical Development Labs.)

    1990-06-01

    The naturally occurring dextrorotary enantiomer (+)-pseudoephedrine was synthesized in the ({sup 3}H)-labelled form with specific activity 17.5 Ci/mmol suitable for development of a radioimmunoassay procedure. The chirally specific route from L-alanine to (1-{sup 3}H)-d-pseudoephedrine hydrochloride was based on the use of {alpha}-amino acids as chiral educts for asymmetric products. (author).

  7. Minocycline hydrochloride nanoliposomes inhibit the production of TNF-α in LPS-stimulated macrophages

    Directory of Open Access Journals (Sweden)

    Liu D

    2012-08-01

    Full Text Available D Liu, P S YangShandong Provincial Key Laboratory of Oral Biomedicine, College of Stomatology, Shandong University, Shandong Province, People's Republic of ChinaBackground: As an adjunctive treatment of chronic periodontitis, it seems that the application of periocline or the other antimicrobials is effective against periodontopathogens. In this study, nanoliposomes were investigated as carriers of minocycline hydrochloride and the inhibition effects of minocycline hydrochloride nanoliposomes on the proliferation and lipopolysaccharide (LPS-stimulated production of tumor necrosis factor-α (TNF-α of macrophages were elucidated.Methods: After stimulation with 10 µg/mL LPS, murine macrophages (ANA-1 were treated with 10, 20, 40, 50 and 70 µg/mL 2% minocycline hydrochloride nanoliposomes, minocycline hydrochloride solution, and periocline for 6, 12, 24, 48 and 60 hours, respectively. A tetrazolium (MTT assay was used to evaluate macrophages cell proliferation rate and the levels of TNF-α mRNA were measured by SYBR Green Real Time PCR.Results: Ten to 70 µg/mL 2% minocycline hydrochloride nanoliposomes, minocycline hydrochloride solution, and periocline showed dose- and time-dependent inhibition of ANA-1 proliferation. Minocycline hydrochloride nanoliposomes showed dose- and ratio-dependent inhibition of LPS-stimulated TNF-α secretion of ANA-1. The inhibition effect of 10 µg/mL minocycline hydrochloride nanoliposomes was significantly better than that of two positive control groups, and equated to that of 60 or 70 µg/mL periocline. The expression of TNF-α mRNA in experimental group continued to reduce linearly with time.Conclusion: All three preparations of minocycline hydrochloride showed dose- and time-dependent inhibition of proliferation of ANA-1. Minocycline hydrochloride nanoliposomes have stronger and longer inhibition effect on LPS-stimulated TNF-α secretion of macrophages cell than minocycline hydrochloride solution and periocline

  8. Clinical effect of venlafaxine combined with methylphenidate hydrochloride on narcolepsy

    Directory of Open Access Journals (Sweden)

    YAN Bin

    2013-11-01

    Full Text Available This study aims to explore the clinical effect of venlafaxine sustained-release capsules combined with methylphenidate hydrochloride tablets on narcolepsy. Thirty-eight cases of narcoleptic patients were randomly divided into venlafaxine combined with methylphenidate hydrochloride treatment group (observation group, N = 19 and methylphenidate hydrochloride and clomipramine treatment group (control group, N = 19. After a total of 12-week treatment, clinical curative effect and adverse drug reactions were observed in 2 groups of patients. The results showed that effective rate of the treatment for excessive daytime sleepiness (EDS in observation group was higher than that of the control group (15/19 vs 8/19, P = 0.044, and effective rate of the treatment for cataplexy in observation group was higher than that of the control group (13/19 vs 6/19, P = 0.048. The rate of adverse drug reactions in observation group was lower than that in the control group (χ2 = 8.889, P = 0.003. It was indicated that venlafaxine combined with methylphenidate had good curative effect on narcolepsy with EDS and cataplexy symptoms.

  9. Atovaquone and proguanil hydrochloride for treatment of malaria.

    Science.gov (United States)

    Kremsner, P G; Looareesuwan, S; Chulay, J D

    1999-05-01

    Safe and effective new drugs are needed for treatment of malaria. Atovaquone and proguanil hydrochloride is a new antimalarial combination that has recently become available in many countries. Data from clinical trials evaluating atovaquone/proguanil for treatment of malaria were reviewed. In 10 open-label clinical trials, treatment of uncomplicated falciparum malaria with 1000 mg atovaquone and 400 mg proguanil hydrochloride (or the equivalent based on body weight in patients proguanil has been used to provide radical cure of asymptomatic Plasmodium falciparum infections prior to initiation of placebo-controlled trials of malaria prophylaxis. Recurrent parasitemia occurred within 28 days in 0 of 99 subjects who subsequently received prophylaxis with atovaquone/proguanil and 1 of 81 subjects who subsequently received placebo. Atovaquone/proguanil is also effective for treatment of malaria caused by the other three Plasmodium species that cause malaria in humans. For treatment of vivax malaria, therapy with primaquine in addition to atovaquone/proguanil is needed to prevent relapse from latent hepatic hypnozoites. Atovaquone and proguanil hydrochloride is a safe and effective combination for treatment of malaria.

  10. Atovaquone and proguanil hydrochloride for prophylaxis of malaria.

    Science.gov (United States)

    Shanks, G D; Kremsner, P G; Sukwa, T Y; van der Berg, J D; Shapiro, T A; Scott, T R; Chulay, J D

    1999-05-01

    The spread of drug-resistant malaria and appreciation of side effects associated with existing antimalarial drugs emphasize the need for new drugs to prevent malaria. The combination of atovaquone and proguanil hydrochloride was previously shown to be safe and highly effective for treatment of malaria, including multi-drug-resistant Plasmodium falciparum. We reviewed results of clinical trials that evaluated either a fixed-dose combination of atovaquone and proguanil hydrochloride for malaria prophylaxis or atovaquone alone for causal prophylactic activity against P. falciparum. In three placebo-controlled trials, 331 subjects received 250 mg atovaquone and 100 mg proguanil hydrochloride (or an equivalent dose based on body weight in children) once daily for 10 to 12 weeks. The overall efficacy for preventing parasitemia was 98%. Among 175 nonimmune volunteers taking the same dose of atovaquone/proguanil once daily for 10 weeks while temporarily residing in a malaria-endemic area, malaria developed in one patient who was noncompliant with therapy. Results of volunteer challenge studies indicate that both atovaquone and proguanil have causal prophylactic activity directed against the liver stages of P. falciparum. Adverse events occurred with similar or lower frequencies in subjects treated with atovaquone/proguanil compared to placebo. Less than 1% of patients discontinued from these studies due to a treatment-related adverse event. A fixed-dose combination of atovaquone and proguanil hydrocloride is a promising new alternative for malaria prophylaxis.

  11. A novel and rapid microbiological assay for ciprofloxacin hydrochloride

    Directory of Open Access Journals (Sweden)

    Edith Cristina Laignier Cazedey

    2013-10-01

    Full Text Available The present work reports a simple, fast and sensitive microbiological assay applying the turbidimetric method for the determination of ciprofloxacin hydrochloride (CIPRO HCl in ophthalmic solutions. The validation method yielded good results and included excellent linearity, precision, accuracy and specificity. The bioassay is based on the inhibitory effect of CIPRO HCl upon the strain of Staphylococcus epidermidis ATCC 12228 used as the test microorganism. The results were treated statistically by analysis of variance (ANOVA and were found to be linear (r=0.9994, in the range of 14.0–56.0 µg/mL, precise (intraday RSD%=2.06; interday RSD%=2.30 and accurate (recovery=99.71%. The turbidimetric assay was compared to the UV spectrophotometric and HPLC methods for the same drug. The turbidimetric bioassay described on this paper for determination of ciprofloxacin hydrochloride in ophthalmic solution is an alternative to the physicochemical methods disclosed in the literature and can be used in quality control routine. Keywords: Antibiotics, Fluoroquinolones, Ciprofloxacin hydrochloride, Quality control, Microbiological assay, Turbidimetric method

  12. Protein antigen adsorption to the DDA/TDB liposomal adjuvant

    DEFF Research Database (Denmark)

    Hamborg, Mette; Jorgensen, Lene; Bojsen, Anders Riber

    2013-01-01

    Understanding the nature of adjuvant-antigen interactions is important for the future design of efficient and safe subunit vaccines, but remains an analytical challenge. We studied the interactions between three model protein antigens and the clinically tested cationic liposomal adjuvant composed...... of dimethyldioctadecylammonium (DDA) and trehalose 6,6'-dibehenate (TDB)....

  13. Distribution of local anesthetics between aqueous and liposome phases

    Czech Academy of Sciences Publication Activity Database

    Ruokonen, S. K.; Duša, Filip; Rantamäki, A. H.; Robciuc, A.; Holma, P.; Holopainen, J. M.; Abdel-Rehim, M.; Wiedmer, S. K.

    2017-01-01

    Roč. 1479, JAN (2017), s. 194-203 ISSN 0021-9673 Institutional support: RVO:68081715 Keywords : liposome electrokinetic chromatography * distribution constants * EOF markers Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 3.981, year: 2016

  14. Antimony to Cure Visceral Leishmaniasis Unresponsive to Liposomal Amphotericin B.

    Directory of Open Access Journals (Sweden)

    Gloria Morizot

    2016-01-01

    Full Text Available We report on 4 patients (1 immunocompetent, 3 immunosuppressed in whom visceral leishmaniasis had become unresponsive to (or had relapsed after treatment with appropriate doses of liposomal amphotericin B. Under close follow-up, full courses of pentavalent antimony were administered without life-threatening adverse events and resulted in rapid and sustained clinical and parasitological cure.

  15. Activity-Based Protein Profiling of Rhomboid Proteases in Liposomes

    Czech Academy of Sciences Publication Activity Database

    Wolf, E. V.; Seybold, M.; Hadravová, Romana; Stříšovský, Kvido; Verhelst, S. H. L.

    2015-01-01

    Roč. 16, č. 11 (2015), s. 1616-1621 ISSN 1439-4227 R&D Projects: GA MŠk(CZ) LK11206; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : activity-based protein profiling * chemical probes * inhibitors * intramembrane proteases * liposomes Subject RIV: CE - Biochemistry Impact factor: 2.850, year: 2015

  16. Gemcitabine-loaded liposomes: rationale, potentialities and future perspectives

    Directory of Open Access Journals (Sweden)

    Federico C

    2012-11-01

    Full Text Available Cinzia Federico, Valeria M Morittu, Domenico Britti, Elena Trapasso, Donato CoscoDepartment of Health Sciences, Building of BioSciences, University “Magna Græcia” of Catanzaro, Campus Universitario “S Venuta”, Germaneto, ItalyAbstract: This review describes the strategies used in recent years to improve the biopharmaceutical properties of gemcitabine, a nucleoside analog deoxycytidine antimetabolite characterized by activity against many kinds of tumors, by means of liposomal devices. The main limitation of using this active compound is the rapid inactivation of deoxycytidine deaminase following administration in vivo. Consequently, different strategies based on its encapsulation/complexation in innovative vesicular colloidal carriers have been investigated, with interesting results in terms of increased pharmacological activity, plasma half-life, and tumor localization, in addition to decreased side effects. This review focuses on the specific approaches used, based on the encapsulation of gemcitabine in liposomes, with particular attention to the results obtained during the last 5 years. These approaches represent a valid starting point in the attempt to obtain a novel, commercializable drug formulation as already achieved for liposomal doxorubicin (Doxil®, Caelyx®.Keywords: gemcitabine, liposomes, multidrug, poly(ethylene glycol, tumors

  17. Rapid Quantification and Validation of Lipid Concentrations within Liposomes

    Directory of Open Access Journals (Sweden)

    Carla B. Roces

    2016-09-01

    Full Text Available Quantification of the lipid content in liposomal adjuvants for subunit vaccine formulation is of extreme importance, since this concentration impacts both efficacy and stability. In this paper, we outline a high performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD method that allows for the rapid and simultaneous quantification of lipid concentrations within liposomal systems prepared by three liposomal manufacturing techniques (lipid film hydration, high shear mixing, and microfluidics. The ELSD system was used to quantify four lipids: 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC, cholesterol, dimethyldioctadecylammonium (DDA bromide, and ᴅ-(+-trehalose 6,6′-dibehenate (TDB. The developed method offers rapidity, high sensitivity, direct linearity, and a good consistency on the responses (R2 > 0.993 for the four lipids tested. The corresponding limit of detection (LOD and limit of quantification (LOQ were 0.11 and 0.36 mg/mL (DMPC, 0.02 and 0.80 mg/mL (cholesterol, 0.06 and 0.20 mg/mL (DDA, and 0.05 and 0.16 mg/mL (TDB, respectively. HPLC-ELSD was shown to be a rapid and effective method for the quantification of lipids within liposome formulations without the need for lipid extraction processes.

  18. Interactions of a Photochromic Spiropyran with Liposome Model Membranes

    KAUST Repository

    Jonsson, Fabian; Beke-Somfai, Tamá s; André asson, Joakim; Nordé n, Bengt

    2013-01-01

    by shear flow, further insight is obtained about interaction and binding geometry of the spiropyran at the lipid membranes. We show that the membrane interactions differ between the two types of liposomes used as well as the isomeric forms of the spiropyran

  19. Single cell targeting using plasmon resonant gold-coated liposomes

    Science.gov (United States)

    Leung, Sarah J.; Romanowski, Marek

    2012-03-01

    We have developed an experimental system with the potential for the delivery and localized release of an encapsulated agent with high spatial and temporal resolution. We previously introduced liposome-supported plasmon resonant gold nanoshells; in this composite structure, the liposome allows for the encapsulation of substances, such as therapeutic agents, neurotransmitters, or growth factors, and the plasmon resonant structure facilitates the rapid release of encapsulated contents upon laser light illumination. More recently, we demonstrated that these gold-coated liposomes are capable of releasing their contents in a spectrally-controlled manner, where plasmon resonant nanoparticles only release content upon illumination with a wavelength of light matching their plasmon resonance band. We now show that this release mechanism can be used in a biological setting to deliver a peptide derivative of cholecystokinin to HEK293 cells overexpressing the CCK2 receptor. Using directed laser light, we may enable localized release from gold-coated liposomes to enable accurate perturbation of cellular functions in response to released compounds; this system may have possible applications in signaling pathways and drug discovery.

  20. Mechanisms of reduction of antitumor drug toxicity by liposome encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Y. E.; Hanson, W. R.; Bharucha, J.; Ainsworth, E. J.; Jaroslow, B.

    1977-01-01

    The antitumor drug Actinomycin D is effective against the growth of some human solid tumors but its use is limited by its extreme toxicity. The development of a method of administering Act. D to reduce its systemic toxicity by incorporating the drug within liposomes reduced its toxicity but its tumoricidal activity was retained.

  1. pH-sensitive liposomes: characterization and application

    International Nuclear Information System (INIS)

    Connor, J.

    1986-01-01

    It has been demonstrated that liposomes composed of dioleoylphosphatidylethanolamine (DOPE) and palmitoylhomocysteine (PHC) have the ability to fuse with adjacent membranes upon exposure to mildly acid pH. The ability of liposomes to fuse is absolutely dependent on the presence of DOPE and a weakly acidic amphiphile. The acid induced fusion event is a leaky process, but the leakage can be reduced by 50%, with only a small loss of fusion ability, by the inclusion of 40 mole percent cholesterol. Using an established monoclonal antibody targeting system. pH-sensitive immunoliposomes were prepared which successfully delivered entrapped calcein to the cytoplasm of target cells. The addition of chloroquine, which raises the internal pH of cellular vacuoles, blocks the cytoplasmic delivery of the pH-sensitive immunoliposomes. pH-insensitive immunoliposomes delivered calcein only to the endosome/lysosome system and not the cytoplasm. 31 P-NMR and light scattering of DOPE:OA liposomes under acidic conditions demonstrate that the effect of the protons and the divalent cations is to force the DOPE to revert to the hexagonal II configuration. In vivo experiments with DOPE:OA immunoliposomes indicate that the liposomes rapidly aggregate and release their contents upon exposure to plasma. These results indicate that pH-sensitive immunoliposomes are an effective tool for in vitro cytoplasmic delivery but are ineffective for in vivo delivery at this point in development

  2. Some factors affecting the valinomycin-induced leak from liposomes

    NARCIS (Netherlands)

    Blok, M.C.; Gier, J. de; Deenen, L.L.M. van

    1974-01-01

    Experiments dealing with the valinomycin-induced K+ leak from egg lecithin liposomes have demonstrated the importance of the enclosed anion. Except when lipophilic anions are enclosed, the addition of both valinomycin and a uncoupler, e.g. carbonylcyanide p-trifluoromethoxyphenylhydrazone, is

  3. Biomolecular Interactions of Tannin Isolated from Oenothera gigas with Liposomes.

    Science.gov (United States)

    Sekowski, Szymon; Ionov, Maksim; Dubis, Alina; Mavlyanov, Saidmukhtar; Bryszewska, Maria; Zamaraeva, Maria

    2016-04-01

    We have examined the interaction between hydrolysable tannin 1-O-galloyl-4,6-hexahydroxydiphenoyl-β-D-glucose (OGβDG) with neutral liposomes as a model of cell membranes composed of three lipids: lecithin, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) at different mass ratios. OGβDG in the concentration range 0.5-15 µg/ml (0.4-12 µM) strongly interacts with liposomal membranes by changing their structure, surface charge and fluidity. Used OGβDG molecules decrease and increase the rigidity of hydrophilic surface and hydrophobic parts of liposomes, respectively. At higher concentrations of tannin (>15 µM), liposomes are aggregated. Fourier Transform Infra-Red (FTIR) analysis showed that mainly -OH groups from OGβDG and also PO(2-) groups from phospholipids are responsible for the interaction. Obtained data indicate the importance of membrane lipid composition in interactions between tannins and cells.

  4. Liposomal photosensitizers: potential platforms for anticancer photodynamic therapy

    Directory of Open Access Journals (Sweden)

    L.A. Muehlmann

    2011-08-01

    Full Text Available Photodynamic therapy is a well-established and clinically approved treatment for several types of cancer. Antineoplastic photodynamic therapy is based on photosensitizers, i.e., drugs that absorb photons translating light energy into a chemical potential that damages tumor tissues. Despite the encouraging clinical results with the approved photosensitizers available today, the prolonged skin phototoxicity, poor selectivity for diseased tissues, hydrophobic nature, and extended retention in the host organism shown by these drugs have stimulated researchers to develop new formulations for photodynamic therapy. In this context, due to their amphiphilic characteristic (compatibility with both hydrophobic and hydrophilic substances, liposomes have proven to be suitable carriers for photosensitizers, improving the photophysical properties of the photosensitizers. Moreover, as nanostructured drug delivery systems, liposomes improve the efficiency and safety of antineoplastic photodynamic therapy, mainly by the classical phenomenon of extended permeation and retention. Therefore, the association of photosensitizers with liposomes has been extensively studied. In this review, both current knowledge and future perspectives on liposomal carriers for antineoplastic photodynamic therapy are critically discussed.

  5. Fluorescence quenching of fluorescein by Merocyanine 540 in liposomes

    International Nuclear Information System (INIS)

    Toprak, Mahmut; Meryem Aydin, Burcu; Arik, Mustafa; Onganer, Yavuz

    2011-01-01

    The fluorescence quenching of fluorescein (FL) by merociyanine 540 (MC540) was examined in L-egg lecithin phosphatidycholine (PC) liposomes using spectroscopic methods. The type of quenching mechanism (dynamic or static) was evaluated using the Stern-Volmer plots. Findings were also supported by the temperature studies and florescence decay measurements. The Stern-Volmer equation was utilized to calculate bimolecular quenching constants (K q ). Furthermore, the bimolecular quenching constant of the quencher in the liposomes (K SV ), partition coefficient (K p ), binding constant (K), and corresponding thermodynamic parameters ΔH, ΔS, and ΔG were calculated. The quenching property was also used in determining quantitatively (K p ) the partition coefficient of Merociyanini 540 in PC liposome.The obtained data indicated that static quenching occurred in the system and the K SV values decreased with increasing lipid concentration. In addition, thermodynamic analysis suggested that van der Waals interactions and hydrogen bonding were the main acting forces between fluorescein and merociyanine 540 molecules in the medium. - Highlights: → Fluorescence quenching of FL by MC540 in liposome system was analyzed. → Fluorescence quenching mechanism of FL by MC540 was consistent with the static model. → Binding FL to MC540 was spontaneous and carried out by hydrogen bond and van der Waals forces.

  6. In vivo toxicity of cationic micelles and liposomes

    DEFF Research Database (Denmark)

    Knudsen, Kristina Bram; Northeved, Helle; Ek, Pramod Kumar

    2015-01-01

    This study investigated toxicity of nanocarriers comprised of cationic polymer and lipid components often used in gene and drug delivery, formulated as cationic micelles and liposomes. Rats were injected intravenously with 10, 25 or 100 mg/kg and sacrificed after 24 or 48 h, or 24 h after the las...

  7. Evaluation of iron transport from ferrous glycinate liposomes using ...

    African Journals Online (AJOL)

    2017-09-03

    Sep 3, 2017 ... Insufficient dietary intake and low iron bio- availability in foods ... pared with common iron supplements, iron liposomes can obviously ... to inhibit iron absorption in humans and in cell culture models11. ..... ical nutrition issues. The effects of .... of approximately 2-100 nm could play an active role in mediating ...

  8. Denaturation/Renaturation of Organophosphorus Acid Anhydrolase (OPAA) Using Guanidinium Hydrochloride and Urea

    National Research Council Canada - National Science Library

    Ong, K. K; Sun, Z; Cheng, T. C; Wei, Y; Yuan, J. M; Yin, R

    2004-01-01

    .... Using organophosphorus acid anhydrolase (OPAA) as the model protein, a guanidinium hydrochloride and urea denaturation/renaturation study was conducted and measured both optically and enzymatically...

  9. Chemical stability of diphenhydramine hydrochloride from an elixir and lidocaine hydrochloride from a viscous solution when mixed together.

    Science.gov (United States)

    Gupta, Vishnu D

    2006-01-01

    The stability of diphenhydramine hydrochloride (from an elixir) and lidocaine hydrochloride (from a viscous solution) in a mixture (1:1) was studied using a stability-indicating high-peformance liquid chromatographic assay method. The concentrations of the drugs were related directly to peak heights and the percent relative standard deviations based on five injections were 1.4 for diphenhydramine and 1.3 for lidocaine. The products of hydrolysis from the both the drugs and a number of excipients present in the dosage forms did not interfere with the developed assay procedure. The mixture was stable for at least 21 days when stored in amber-colored bottles at room temperature. The pH value of the mixture remained constant, and the physical appearance did not change during the study period.

  10. Use of xylazine hydrochloride-ketamine hydrochloride for immobilization of wild leopards (Panthera pardus fusca) in emergency situations.

    Science.gov (United States)

    Belsare, Aniruddha V; Athreya, Vidya R

    2010-06-01

    In India, leopards (Panthera pardus fusca) inhabit human-dominated landscapes, resulting in encounters that require interventions to prevent harm to people, as well as the leopards. Immobilization is a prerequisite for any such intervention. Such emergency field immobilizations have to be carried out with limited tools, often amidst large uncontrollable crowds. An effective and practicable approach is discussed, based on 55 wild leopard immobilizations undertaken between January 2003 and April 2008. A xylazine hydrochloride (1.4 +/- 0.3 mg/kg)--ketamine hydrochloride (5 +/- 2 mg/kg) mixture was used for immobilization of leopards, based on estimated body weight. When weight could not be estimated, a standard initial dose of 50 mg of xylazine--150 mg of ketamine was used. Supplemental doses (50-75 mg) of only ketamine were used as required. No life-threatening adverse effects of immobilization were documented for at least 1 mo postimmobilization.

  11. Thermodynamic studies of drug–α-cyclodextrin interactions in water at 298.15 K: Procaine hydrochloride/lidocaine hydrochloride/tetracaine hydrochloride/ranitidine hydrochloride + α-cyclodextrin + H2O systems

    International Nuclear Information System (INIS)

    Shaikh, Vasim R.; Terdale, Santosh S.; Hundiwale, Dilip G.; Patil, Kesharsingh J.

    2014-01-01

    Graphical abstract: The encapsulation of guest tetracaine hydrochloride TC·HCl (C 15 H 24 N 2 O 2 ·HCl), in α-cyclodextrin cavities in aqueous solutions at 298.15 K. -- Highlights: • The osmotic coefficient measurements are reported for PC·HCl/LC·HCl/TC·HCl/RT·HCl + 0.1 m α-CD + water at 298.15 K. • The concentration variation of mean activity coefficients of drug molecules in water–α-CD solutions has been studied. • The transfer Gibbs free energies have been calculated using the activity data. • Pair and triplet interaction parameters and equilibrium constant (log K) values are also estimated. • The results are discussed with emphasis on host–guest interaction concepts. -- Abstract: The osmotic coefficient measurements have been carried out for ternary aqueous solutions containing a fixed concentration of α-cyclodextrin (α-CD) of ∼0.1 mol · kg −1 and varying the concentrations (∼0.012 to ∼0.21 mol · kg −1 ) of drugs Procaine hydrochloride (PC·HCl), Lidocaine hydrochloride (LC·HCl), Tetracaine hydrochloride (TC·HCl) and Ranitidine hydrochloride (RT·HCl) at 298.15 K using vapour pressure osmometry. The water activities for each ternary system were measured and used to obtain the activity coefficients of α-cyclodextrin (α-CD) and drugs following the methodology developed by Robinson and Stokes for isopiestic measurements. The transfer Gibbs free energies of electrolyte (or drug) from water to an aqueous nonelectrolyte (α-CD) solutions (ΔG tr E ) and that of nonelectrolyte (α-CD) from water to an aqueous electrolyte (or drug) solutions (ΔG tr N ) have been calculated using the activity data. These were further used for the estimation of pair and triplet interaction parameters. By applying the method based on the application of the McMillan–Mayer theory of virial coefficients to transfer free energy data, the salting constant (k s ) values have been estimated at 298.15 K. The equilibrium constant (log K) values for the

  12. Superresolution and Fluorescence Dynamics Evidence Reveal That Intact Liposomes Do Not Cross the Human Skin Barrier.

    Directory of Open Access Journals (Sweden)

    Jes Dreier

    Full Text Available In this study we use the combination of super resolution optical microscopy and raster image correlation spectroscopy (RICS to study the mechanism of action of liposomes as transdermal drug delivery systems in human skin. Two different compositions of liposomes were applied to newly excised human skin, a POPC liposome and a more flexible liposome containing the surfactant sodium cholate. Stimulated emission depletion microscopy (STED images of intact skin and cryo-sections of skin treated with labeled liposomes were recorded displaying an optical resolution low enough to resolve the 100 nm liposomes in the skin. The images revealed that virtually none of the liposomes remained intact beneath the skin surface. RICS two color cross correlation diffusion measurements of double labeled liposomes confirmed these observations. Our results suggest that the liposomes do not act as carriers that transport their cargo directly through the skin barrier, but mainly burst and fuse with the outer lipid layers of the stratum corneum. It was also found that the flexible liposomes showed a greater delivery of the fluorophore into the stratum corneum, indicating that they functioned as chemical permeability enhancers.

  13. Liposomes equipped with cell penetrating peptide BR2 enhances chemotherapeutic effects of cantharidin against hepatocellular carcinoma.

    Science.gov (United States)

    Zhang, Xue; Lin, Congcong; Lu, Aiping; Lin, Ge; Chen, Huoji; Liu, Qiang; Yang, Zhijun; Zhang, Hongqi

    2017-11-01

    A main hurdle for the success of tumor-specific liposomes is their inability to penetrate tumors efficiently. In this study, we incorporated a cell-penetrating peptide BR2 onto the surface of a liposome loaded with the anticancer drug cantharidin (CTD) to create a system targeting hepatocellular carcinoma (HCC) cells more efficiently and effectively. The in vitro cytotoxicity assay comparing the loaded liposomes' effects on hepatocellular cancer HepG2 and the control Miha cells showed that CTD-loaded liposomes had a stronger anticancer effect after BR2 modification. The cellular uptake results of HepG2 and Miha cells further confirmed the superior ability of BR2-modified liposomes to penetrate cancer cells. The colocalization study revealed that BR2-modified liposomes could enter tumor cells and subsequently release drugs. A higher efficiency of delivery by BR2 liposomes as compared to unmodified liposomes was evident by evaluation of the HepG2 tumor spheroids penetration and inhibition. The biodistribution studies and anticancer efficacy results in vivo showed the significant accumulation of BR2-modified liposomes into tumor sites and an enhanced tumor inhibition. In conclusion, BR2-modified liposomes improve the anticancer potency of drugs for HCC.

  14. Physicochemical aspects of the liposome-wool interaction in wool dyeing.

    Science.gov (United States)

    Martí, Meritxell; Barsukov, Leonid I; Fonollosa, Jordi; Parra, José Luis; Sukhanov, Stanislav V; Coderch, Luisa

    2004-04-13

    Despite the promising application of liposomes in wool dyeing, little is known about the mechanism of liposome interactions with the wool fiber and dyestuffs. The kinetics of wool dyeing by two dyes, Acid Green 27 (hydrophobic) and Acid Green 25 (hydrophilic), were compared in three experimental protocols: (1) without liposomes, (2) in the presence of phosphatidylcholine (PC) liposomes, and (3) with wool previously treated with PC liposomes. Physicochemical interactions of liposomes with wool fibers were studied under experimental dyeing conditions with particular interest in the liposome affinity to the fiber surface and changes in the lipid composition of the wool fibers. The results obtained indicate that the presence of liposomes favors the retention of these two dyes in the dyeing bath, this effect being more pronounced in case of the hydrophobic dye. Furthermore, the liposome treatment is accompanied by substantial absorption of PC by wool fibers with simultaneous partial solubilization of their polar lipids (more evident at higher temperatures). This may result in structural modification of the cell membrane complex of wool fibers, which could account for a high level of the dye exhaustion observed at the end of the liposome dyeing process.

  15. A Liposomal Formulation Able to Incorporate a High Content of Paclitaxel and Exert Promising Anticancer Effect

    Directory of Open Access Journals (Sweden)

    Pei Kan

    2011-01-01

    Full Text Available A liposome formulation for paclitaxel was developed in this study. The liposomes, composed of naturally unsaturated and hydrogenated phosphatidylcholines, with significant phase transition temperature difference, were prepared and characterized. The liposomes exhibited a high content of paclitaxel, which was incorporated within the segregated microdomains coexisting on phospholipid bilayer of liposomes. As much as 15% paclitaxel to phospholipid molar ratio were attained without precipitates observed during preparation. In addition, the liposomes remained stable in liquid form at 4∘C for at least 6 months. The special composition of liposomal membrane which could reduce paclitaxel aggregation could account for such a capacity and stability. The cytotoxicity of prepared paclitaxel liposomes on the colon cancer C-26 cell culture was comparable to Taxol. Acute toxicity test revealed that LD50 for intravenous bolus injection in mice exceeded by 40 mg/kg. In antitumor efficacy study, the prepared liposomal paclitaxel demonstrated the increase in the efficacy against human cancer in animal model. Taken together, the novel formulated liposomes can incorporate high content of paclitaxel, remaining stable for long-term storage. These animal data also demonstrate that the liposomal paclitaxel is promising for further clinical use.

  16. Liposomes as potential carrier system for targeted delivery of polyene antibiotics.

    Science.gov (United States)

    Naik, Suresh R; Desai, Sandhya K; Shah, Priyank D; Wala, Santosh M

    2013-09-01

    The development of new therapeutic modalities involves the use of drug carrier, such as liposomes, which can modify pharmacokinetic and bio-distribution of drug profile. Polyene antibiotics incorporation into liposomes improves its availability at the site, bio-distribution and therapeutic index mainly through the engulfment of liposomes by circulating monocytes/macrophages and transportation to the site of infection. Polyene antibiotics (AmB, SJA-95, HA-1-92) and other antibiotics (streptomycin, tobramycin, quinolones, anti-tubercular and anti-cancer drugs), liposomal preparations are described with possible advantages from therapeutic efficacy and toxicity point of view. The polyene macrolide antibiotics liposomal preparations proved to be more effective in the treatment of systemic mycosis. The AmB-cyclodextrin derivatives inclusion complex is a major breakthrough in liposomal preparation which can be converted into aqueous phase of liposome. Liposomal drug incorporated preparation has been one of the important areas of research for developing the existing polyene antibiotics into useful chemotherapeutic agents in clinical medicine. In recent past other antibiotics have also been incorporated into liposomes using wide variety of materials, phosphatidylethanolamine derivatives (pegylated liposomes, enzyme sensitive conjugates, fluidosomes of anti-cancer drugs and poly lactic/glycolic acid microspheres for anti-tuberculosis drugs). In addition, attempts were also made to extend the receptor mediated drug targeting and to review some relevant patents.

  17. An evaluation of anti-tumor effect and toxicity of PEGylated ursolic acid liposomes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qianqian; Zhao, Tingting; Liu, Yanping; Xing, Shanshan; Li, Lei; Gao, Dawei, E-mail: dwgao@ysu.edu.cn [Yanshan University, Applying Chemistry Key Lab of Hebei Province, Department of Bioengineer (China)

    2016-02-15

    Therapy of solid tumors mediated by nano-drug delivery has attracted considerable interest. In our previous study, ursolic acid (UA) was successfully encapsulated into PEGylated liposomes. The study aimed to evaluate the tumor inhibition effect and cytotoxicity of the PEGylated UA liposomes by U14 cervical carcinoma-bearing mice. The liposomes were spherical particles with mean particle diameters of 127.2 nm. The tumor inhibition rate of PEGylated UA liposomes was 53.60 % on U14 cervical carcinoma-bearing mice, which was greater than those of the UA solution (18.25 %) and traditional UA liposome groups (40.75 %). The tumor cells apoptosis rate of PEGylated UA liposomes was 25.81 %, which was significantly higher than that of the traditional UA liposomes (13.37 %). Moreover, the kidney and liver did not emerge the pathological changes in UA therapeutic mice by histopathological analysis, while there were significant differences on tumor tissues among three UA formulation groups. The PEGylated UA liposomes exhibited higher anti-tumor activity and lower cytotoxicity, and the main reason was that the coating PEG layer improved UA liposome properties, such as enhancing the stability of liposomes, promoting the effect of slow release, and prolonging the time of blood circulation. This may shed light on the development of PEGylated nano-vehicles.

  18. A targeting drug-delivery model via interactions among cells and liposomes under ultrasonic excitation

    International Nuclear Information System (INIS)

    Xi Xiaoyu; Zhang Dong; Yang Fang; Gu Ning; Chen Di; Wu Junru; Luo Yi

    2008-01-01

    In our previous work, it was found that acoustic cavitation might play a role in improving the cell permeability to microparticles when liposomes were used in an in vitro experiment. The purpose of this project is to expand our study and to learn other possible mechanisms by which cells may interact with liposomes under ultrasound (US) excitation and become transiently permeable to microparticles. It is further hypothesized that two possible scenarios may be involved in in vitro experiments: (1) drug-carrying liposomes transiently overcome the cell membrane barrier and enter into a cell while the cell is still viable; (2) the liposomes incorporate with a cell at its membrane through a fusing process. To prove this hypothesis, liposomes of two different structures were synthesized: one has fluorescent molecules encapsulated into liposomes and the other has fluorescent markers incorporated into the shells of liposomes. Liposomes of each kind were mixed with human breast cancer cells (MCF7-cell line) in a suspension at 5 (liposomes) : 1 (cell) ratio and were then exposed to a focused 1 MHz ultrasound beam at its focal region for 40 s. The US signal contained 20 cycles per tone-burst at a pulse-repetition-frequency of 10 kHz; the spatial peak acoustic pressure amplitude was 0.25 MPa. It was found that the possible mechanisms might include the acoustic cavitation, the endocytosis and cell-fusion. Acoustic radiation force might make liposomes collide with cells effectively and facilitate the delivery process

  19. Silica-based monolithic capillary columns modified by liposomes for characterization of analyte–liposome interactions by capillary liquid chromatography

    Czech Academy of Sciences Publication Activity Database

    Moravcová, Dana; Planeta, Josef; Wiedmer, S. K.

    2013-01-01

    Roč. 1317, SI (2013), s. 159-166 ISSN 0021-9673 R&D Projects: GA MV VG20112015021; GA ČR(CZ) GAP206/11/0138 Institutional support: RVO:68081715 Keywords : monolithic silica capillary column * immobilized liposomes * biomimicking stationary phase Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.258, year: 2013

  20. Degree of corneal anaesthesia after topical application of 0.4% oxybuprocaine hydrochloride and 0.5% proparacaine hydrochloride ophthalmic solution in clinically normal cattle.

    Science.gov (United States)

    Little, W B; Jean, G St; Sithole, F; Little, E; Jean, K Yvorchuk-St

    2016-06-01

    The use of corneal anaesthesia is necessary for a range of clinical purposes. Therefore, we assessed and compared the efficacy of corneal anaesthesia after application of 0.4% oxybuprocaine hydrochloride and 0.5% proparacaine hydrochloride ophthalmic solution in clinically normal cattle. The 24 clinically normal cows were allocated into two groups. Cows in group 1 (n = 12) received 0.2 mL of 0.4% oxybuprocaine hydrochloride with fluorescein ophthalmic solution in one eye and 0.2 mL of sterile saline (0.9% NaCl) with fluorescein in the contralateral eye (control). Group 2 (n = 12) received 0.2 mL of 0.4% oxybuprocaine hydrochloride with fluorescein ophthalmic solution in one eye and 0.2 mL of 0.5% proparacaine hydrochloride with fluorescein in the contralateral eye (control). In each group, corneal touch threshold was determined by Cochet-Bonnet aesthesiometer for both eyes immediately prior to topical administration of solutions, at 1 min and 5 min after administration of topical solutions and every 5 min thereafter for a total of 75 min. Significant corneal anaesthesia was noted immediately following topical application of both oxybuprocaine and proparacaine as compared with controls, with maximal corneal anaesthesia noted 1 min after administration. Both oxybuprocaine and proparacaine produced significant corneal anaesthesia for the duration of the 75-min study. Neither oxybuprocaine hydrochloride nor proparacaine hydrochloride treatment resulted in visible adverse effects. There are limited data available demonstrating the efficacy and duration of corneal anaesthetic agents in cattle. Both oxybuprocaine hydrochloride and proparacaine hydrochloride should be considered practical options for providing corneal anaesthesia in cattle in a clinical setting. © 2016 Australian Veterinary Association.

  1. Dual-coating of liposomes as encapsulating matrix of antimicrobial peptides: Development and characterization

    Science.gov (United States)

    Gomaa, Ahmed I.; Martinent, Cynthia; Hammami, Riadh; Fliss, Ismail; Subirade, Muriel

    2017-11-01

    Abstract Antimicrobial peptides have been proposed as a potential biopreservatives in pharmaceutical research and agribusiness. However, many limitations hinder their utilization, such as their vulnerability to proteolytic digestion and their potential interaction with other food ingredients in complex food systems. One approach to overcome such problems is developing formulations entrapping and thereby protecting the antimicrobial peptides. Liposome encapsulation is a strategy that could be implemented to combine protection of the antimicrobial activity of the peptides from proteolytic enzymes and the controlled release of the encapsulated active ingredients. The objective of this study was to develop dual-coated food grade liposome formulations for oral administration of bacteriocins. The formulations were developed from anionic and cationic phospholipids as models of negatively and positively charged liposomes, respectively. Liposomes were prepared by the hydration of lipid films. Subsequently, the liposomes were coated with two layers comprising a biopolymer network (pectin) and whey proteins (WPI) in order to further improve their stability and enable the gradual release of the developed liposomes. Liposomes were characterized for their size, charge, molecular structure, morphology, encapsulation efficiency and release. The results of FTIR, zeta potential, size distribution and transmission electron microscopy confirmed that the liposomes were efficiently coated. Ionic interactions were involved in the stabilization of the positively charged liposome formulations. Negatively charge liposome formulations were stabilized through weak interactions. The release study proved the efficiency of dual coating on the protection of liposomes against gastrointestinal digestion. This work is the first to study the encapsulation of antimicrobial peptides in dual-coated liposomes. Furthermore, the work successfully encapsulated MccJ25 in both negative and positive liposome

  2. Polymer coated liposomes for dental drug delivery--interactions with parotid saliva and dental enamel.

    Science.gov (United States)

    Nguyen, S; Hiorth, M; Rykke, M; Smistad, G

    2013-09-27

    The interactions between pectin coated liposomes and parotid saliva and dental enamel were studied to investigate their potential to mimic the protective biofilm formed naturally on tooth surfaces. Different pectin coated liposomes with respect to pectin type (LM-, HM- and AM-pectin) and concentration (0.05% and 0.2%) were prepared. Interactions between the pectin coated liposomes and parotid saliva were studied by turbidimetry and imaging by atomic force microscopy. The liposomes were adsorbed to hydroxyapatite (HA) and human dental enamel using phosphate buffer and parotid saliva as adsorption media. A continuous flow was imposed on the enamel surfaces for various time intervals to examine their retention on the dental enamel. The results were compared to uncoated, charged liposomes. No aggregation tendencies for the pectin coated liposomes and parotid saliva were revealed. This makes them promising as drug delivery systems to be used in the oral cavity. In phosphate buffer the adsorption to HA of pectin coated liposomes was significantly lower than the negative liposomes. The difference diminished in parotid saliva. Positive liposomes adsorbed better to the dental enamel than the pectin coated liposomes. However, when subjected to flow for 1h, no significant differences in the retention levels on the enamel were found between the formulations. For all formulations, more than 40% of the liposomes still remained on the enamel surfaces. At time point 20 min the retention of HM-pectin coated and positive liposomes were significantly higher. It was concluded that pectin coated liposomes can adsorb to HA as well as to the dental enamel. Their ability to retain on the enamel surfaces promotes the concept of using them as protective structures for the teeth. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Interaction between lidocaine hydrochloride (with and without adrenaline) and various irrigants: A nuclear magnetic resonance analysis.

    Science.gov (United States)

    Vidhya, Nirmal; Karthikeyan, Balasubramanian Saravana; Velmurugan, Natanasabapathy; Abarajithan, Mohan; Nithyanandan, Sivasankaran

    2014-05-01

    Interaction between local anesthetic solution, lidocaine hydrochloride (with and without adrenaline), and root canal irrigants such as sodium hypochlorite (NaOCl), ethylene diamine tetra-acetic acid (EDTA), and chlorhexidine (CHX) has not been studied earlier. Hence, the purpose of this in vitro study was to evaluate the chemical interaction between 2% lidocaine hydrochloride (with and without adrenaline) and commonly used root canal irrigants, NaOCl, EDTA, and CHX. SAMPLES WERE DIVIDED INTO EIGHT EXPERIMENTAL GROUPS: Group I-Lidocaine hydrochloride (with adrenaline)/3% NaOCl, Group II-Lidocaine hydrochloride (with adrenaline)/17% EDTA, Group III- Lidocaine hydrochloride (with adrenaline)/2% CHX, Group IV-Lidocaine hydrochloride (without adrenaline)/3% NaOCl, Group V-Lidocaine hydrochloride (without adrenaline)/17% EDTA, Group VI-Lidocaine hydrochloride (without adrenaline)/2% CHX, and two control groups: Group VII-Lidocaine hydrochloride (with adrenaline)/deionized water and Group VIII-Lidocaine hydrochloride (without adrenaline)/deionized water. The respective solutions of various groups were mixed in equal proportions (1 ml each) and observed for precipitate formation. Chemical composition of the formed precipitate was then analysed by nuclear magnetic resonance spectroscopy (NMR) and confirmed with diazotation test. In groups I and IV, a white precipitate was observed in all the samples on mixing the respective solutions, which showed a color change to reddish brown after 15 minutes. This precipitate was then analysed by NMR spectroscopy and was observed to be 2,6-xylidine, a reported toxic compound. The experimental groups II, III, V, and VI and control groups VII and VIII showed no precipitate formation in any of the respective samples, until 2 hours. Interaction between lidocaine hydrochloride (with and without adrenaline) and NaOCl showed precipitate formation containing 2,6-xylidine, a toxic compound.

  4. Acoustic Studies on Nanodroplets, Microbubbles and Liposomes

    Science.gov (United States)

    Kumar, Krishna Nandan

    in vitro study aimed at developing an ultrasound-aided noninvasive pressure estimation technique using contrast agents-DefinityRTM, a lipid coated microbubble, and an experimental PLA (Poly lactic acid) microbubbles. Scattered responses from these bubbles have been measured in vitro as a function of ambient pressure using a 3.5 MHz acoustic excitation of varying amplitude. At an acoustic pressure of 670 kPa, Definity RTM microbubbles showed a linear decrease in subharmonic signal with increasing ambient pressure, registering a 12dB reduction at an overpressure of 120 mm Hg. Ultrasound contrast microbubbles experience widely varying ambient blood pressure in different organs, which can also change due to diseases. Pressure change can alter the material properties of the encapsulation of these microbubbles. Here the characteristic rheological parameters of contrast agent Definity and Targestar are determined by varying the ambient pressure (in a physiologically relevant range 0-200 mmHg). Four different interfacial rheological models are used to characterize the microbubbles. Both the contrast agents show an increase in their interfacial dilatational viscosity and interfacial dilatational elasticity with ambient pressure. It has been well established that liposomes prepared following a careful multi-step procedure can be made echogenic. Our group as well as others experimentally demonstrated that freeze-drying in the presence of mannitol is a crucial component to ensure echogenicity. Here, we showed that freeze-dried aqueous solutions of excipients such as mannitol, meso-erythritol, glycine, and glucose that assume a crystalline state, when dispersed in water creates bubbles and are echogenic even without any lipids. We also present an explanation for the bubble generation process because of dissolution of mannitol.

  5. Application of 10B entrapped PEG-liposome to boron neutron-capture therapy for pancreatic cancer model in vivo

    International Nuclear Information System (INIS)

    Yanagie, H.; Eriguchi, M.; Maruyama, K.; Takizawa, T.; Ishida, O.; Ogura, K.; Matsumoto, T.; Sakurai, Y.; Kobayashi, T.; Ono, K.; Rant, J.; Skvarc, J.; Ilic, R.; Shinohara, A.; Chiba, M.; Kobayashi, H.

    1999-01-01

    The cytotoxic effects for tumor were evaluated with intravenous injection 10 B PEG-liposome (Stealth liposome) on human pancreatic carcinoma wenografts in nude mice with thermal neutron irradiation. After thermal neutron irradiation of mice injected with 10 B bare-liposome or 10 B PEG liposome, AsPC-1 tumour growth was suppressed relative to controls. Injection of 10 B PEG-liposome caused the greatest tumour suppression with thermal neutron irradiation in vivo. These results suggest that intravenous injection of 10 B PEG-liposome can increase the retention of 10 B atoms by tumor cells, causing tumor growth suppression in vivo upon thermal neutron irradiation.(author)

  6. Simultant encapsulation of vitamin C and beta-carotene in sesame (Sesamum indicum l.) liposomes

    Science.gov (United States)

    Hudiyanti, D.; Fawrin, H.; Siahaan, P.

    2018-04-01

    In this study sesame liposomes were used to encapsulate both vitamin C and beta-carotene simultaneously. Liposomes were prepared with addition of cholesterol. The encapsulation efficiency (EE) of sesame liposomes for vitamin C in the present of beta-carotene was 77%. The addition of cholesterol increased the encapsulation efficiency. The highest encapsulation efficiency was 89% obtained in liposomes with 10% and 20% cholesterol. Contrary to that, the highest beta-carotene encapsulation efficiency of 78%, was found in the sesame liposomes prepared without the added cholesterol. Results showed that sesame liposomes can be used to encapsulate beta-carotene and vitamin C simultaneously. When beta-carotene and vitamin C were encapsulated concurrently, cholesterol intensified the efficiency of vitamin C encapsulation on the contrary it diminished the efficiency of beta-carotene encapsulation.

  7. Barriers to Liposomal Gene Delivery: from Application Site to the Target.

    Science.gov (United States)

    Saffari, Mostafa; Moghimi, Hamid Reza; Dass, Crispin R

    2016-01-01

    Gene therapy is a therapeutic approach to deliver genetic material into cells to alter their function in entire organism. One promising form of gene delivery system (DDS) is liposomes. The success of liposome-mediated gene delivery is a multifactorial issue and well-designed liposomal systems might lead to optimized gene transfection particularly in vivo. Liposomal gene delivery systems face different barriers from their site of application to their target, which is inside the cells. These barriers include presystemic obstacles (epithelial barriers), systemic barriers in blood circulation and cellular barriers. Epithelial barriers differ depending on the route of administration. Systemic barriers include enzymatic degradation, binding and opsonisation. Both of these barriers can act as limiting hurdles that genetic material and their vector should overcome before reaching the cells. Finally liposomes should overcome cellular barriers that include cell entrance, endosomal escape and nuclear uptake. These barriers and their impact on liposomal gene delivery will be discussed in this review.

  8. Oral administration of insulin by means of liposomes in animal experiments

    International Nuclear Information System (INIS)

    Tragl, K.H.; Pohl, A.; Kinast, H.

    1979-01-01

    Liposomes are an effective vehicle for the oral administration of insulin. They are prepared from lipid emulsions by sonication and particles of homogeneous size are generated by elution through sepharose columns. Liposomes are taken up into the gastric mucosa by endocytosis and then transported to the liver via the portal circulation. Oral administration of 10 U insulin/kg body weight to rats is followed by a reduction in blood glucose to 67% of the initial value. When liposome-trapped insulin was injected intravenously a decrease in blood glucose to 40% of the initial value was obtained by the administration of 5 IU insulin/kg body weight. While the effect of orally-administered liposome-trapped insulin is obvious, the problems of standardization of the insulin content of the liposomes and the great variability of liposome uptake into the gastric mucosa by endocytosis remain unsolved. (author)

  9. Inhibitory effect of liposome-entrapped lemongrass oil on the growth of Listeria monocytogenes in cheese.

    Science.gov (United States)

    Cui, H Y; Wu, J; Lin, L

    2016-08-01

    Listeria monocytogenes infection in dairy products is of mounting public concern. To inhibit bacterial growth, we engineered stimuli-responsive liposomes containing lemongrass oil for this study. The controlled release of liposome-entrapped lemongrass oil is triggered by listerolysin O, secreted by L. monocytogenes. We investigated the antibiotic activities of lemongrass oil liposomes against L. monocytogenes in cheese. We also assessed their possible effects on the quality of the cheese. Liposomes containing lemongrass oil (5.0mg/mL) presented the optimal polydispersity index (0.246), zeta-potential (-58.9mV) and entrapment efficiency (25.7%). The liposomes displayed satisfactory antibiotic activity against L. monocytogenes in cheese over the storage period at 4°C. We observed no effects on the physical and sensory properties of the cheese after the liposome treatment. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. Structure of liposome encapsulating proteins characterized by X-ray scattering and shell-modeling

    International Nuclear Information System (INIS)

    Hirai, Mitsuhiro; Kimura, Ryota; Takeuchi, Kazuki; Hagiwara, Yoshihiko; Kawai-Hirai, Rika; Ohta, Noboru; Igarashi, Noriyuki; Shimuzu, Nobutaka

    2013-01-01

    Wide-angle X-ray scattering data using a third-generation synchrotron radiation source are presented. Lipid liposomes are promising drug delivery systems because they have superior curative effects owing to their high adaptability to a living body. Lipid liposomes encapsulating proteins were constructed and the structures examined using synchrotron radiation small- and wide-angle X-ray scattering (SR-SWAXS). The liposomes were prepared by a sequential combination of natural swelling, ultrasonic dispersion, freeze-throw, extrusion and spin-filtration. The liposomes were composed of acidic glycosphingolipid (ganglioside), cholesterol and phospholipids. By using shell-modeling methods, the asymmetric bilayer structure of the liposome and the encapsulation efficiency of proteins were determined. As well as other analytical techniques, SR-SWAXS and shell-modeling methods are shown to be a powerful tool for characterizing in situ structures of lipid liposomes as an important candidate of drug delivery systems

  11. Conventional and dense gas techniques for the production of liposomes: a review.

    Science.gov (United States)

    Meure, Louise A; Foster, Neil R; Dehghani, Fariba

    2008-01-01

    The aim of this review paper is to compare the potential of various techniques developed for production of homogenous, stable liposomes. Traditional techniques, such as Bangham, detergent depletion, ether/ethanol injection, reverse-phase evaporation and emulsion methods, were compared with the recent advanced techniques developed for liposome formation. The major hurdles for scaling up the traditional methods are the consumption of large quantities of volatile organic solvent, the stability and homogeneity of the liposomal product, as well as the lengthy multiple steps involved. The new methods have been designed to alleviate the current issues for liposome formulation. Dense gas liposome techniques are still in their infancy, however they have remarkable advantages in reducing the use of organic solvents, providing fast, single-stage production and producing stable, uniform liposomes. Techniques such as the membrane contactor and heating methods are also promising as they eliminate the use of organic solvent, however high temperature is still required for processing.

  12. In situ SAXS experiment during DNA and liposome complexation

    Energy Technology Data Exchange (ETDEWEB)

    Gasperini, A.A.; Cavalcanti, L.P. [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Balbino, T.A.; Torre, L.G. de la [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Oliveira, C.L.P. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil)

    2012-07-01

    Full text: Gene therapy is an exciting research area that allows the treatment of different diseases. Basically, an engineered DNA that codes a protein is the therapeutic drug that has to be delivered to the cell nucleus. After that, the DNA transfection process allows the protein production using the cell machinery. However, the efficient delivery needs DNA protection against nucleases and interstitial fluids. In this context, the use of cationic liposome/DNA complexes is a promising strategy for non-viral gene therapy. Liposomes are lipid systems that self-aggregate in bilayers and the use of cationic lipids allows the electrostatic complexation with DNA. In this work, we used SAXS technique to study the complexation kinetics between cationic liposomes and plasmid DNA and evaluate the liposome structural modifications in the presence of DNA. Liposomes were prepared according to [1] using as plasmid DNA vector model a modified version of pVAX1-GFP with luciferase as reporter gene [2]. The complexation was promoted in a SAXS sample holder containing a microchannel to get access to the compartment between two mica windows where the X-ray beam could cross through [3]. We obtained in situ complexation using such sample holder coupled to a fed-batch reactor through a peristaltic pump. The scattering curves were recorded each 30 seconds during the cycles. The DNA was added until a certain final ratio between surface charges previously determined. We studied the form and structure factor model for the liposome bilayer to fit the scattering curves [4]. Structural information such as the bilayer electronic density profiles, number of bilayers and fluidity were determined as a function of the complexation with DNA. These differences can reflect in singular in vitro and in vivo effects. [1] L. G. de la Torre et al. Colloids and Surfaces B: Biointerfaces, 73, 175 (2009) [2] A. R. Azzoni et al. The Journal of Gene Medicine, 9, 392 (2007) [3] L. P. Cavalcanti et al. Review of

  13. 21 CFR 520.1242b - Levamisole hydrochloride tablet or oblet (bolus).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Levamisole hydrochloride tablet or oblet (bolus... § 520.1242b Levamisole hydrochloride tablet or oblet (bolus). (a) Chemical name. (-)-2,3,5,6-Tetrahydro... using in severely debilitated animals. (2) It is used in a tablet for sheep as follows: (i) Amount. 0...

  14. 21 CFR 520.2345h - Tetracycline hydrochloride, sodium novobiocin, and prednisolone tablets.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tetracycline hydrochloride, sodium novobiocin, and... ANIMAL DRUGS § 520.2345h Tetracycline hydrochloride, sodium novobiocin, and prednisolone tablets. (a... the first stage of parturition when administered during the last trimester of pregnancy and may...

  15. 21 CFR 524.1662 - Oxytetracycline hydrochloride ophthalmic and topical dosage forms.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride ophthalmic and topical dosage forms. 524.1662 Section 524.1662 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... DOSAGE FORM NEW ANIMAL DRUGS § 524.1662 Oxytetracycline hydrochloride ophthalmic and topical dosage forms. ...

  16. 21 CFR 522.1662 - Oxytetracycline hydrochloride implantation or injectable dosage forms.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride implantation or injectable dosage forms. 522.1662 Section 522.1662 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1662 Oxytetracycline hydrochloride implantation or injectable...

  17. Evaluation of liposomes coated with a pH responsive polymer

    OpenAIRE

    Barea, M.J.; Jenkins, M.J.; Gaber, M.H.; Bridson, R.H.

    2010-01-01

    Liposomes have been coated with the pH responsive polymer, Eudragit S100, and the formulation's potential for lower gastrointestinal (GI) targeting following oral administration assessed. Cationic liposomes were coated with the anionic polymer through simple mixing. The evolution of a polymer coat was studied using zeta potential measurements and laser diffraction size analysis. Further evidence of an association between polymer and liposome was obtained using light and cryo scanning electron...

  18. Films of Agarose Enable Rapid Formation of Giant Liposomes in Solutions of Physiologic Ionic Strength

    OpenAIRE

    Horger, Kim S.; Estes, Daniel J.; Capone, Ricardo; Mayer, Michael

    2009-01-01

    This paper describes a method to form giant liposomes in solutions of physiologic ionic strength, such as phosphate buffered saline (PBS) or 150 mM KCl. Formation of these cell-sized liposomes proceeded from hybrid films of partially dried agarose and lipids. Hydrating the films of agarose and lipids in aqueous salt solutions resulted in swelling and partial dissolution of the hybrid films and in concomitant rapid formation of giant liposomes in high yield. This method did not require the pre...

  19. Interaction of dendritic cells with antigen-containing liposomes: effect of bilayer composition

    DEFF Research Database (Denmark)

    Foged, Camilla; Arigita, Carmen; Sundblad, Anne

    2004-01-01

    the interaction of negatively charged liposomes with both human and murine DCs. This increase could be blocked in human DCs by addition of the polysaccharide mannan indicating that uptake might be mediated by the mannose receptor. Cationic liposomes containing trimethyl ammonium propane interacted with a very...... high percentage of both DC types and could be detected in high amounts intracellularly. In conclusion, liposome bilayer composition has an important effect on interaction with DCs and might be critical for the vaccination outcome....

  20. The Physical Characterization of Liposome Salicylic Acid Using Transmission Electron Microscope

    International Nuclear Information System (INIS)

    Elman Panjaitan

    2008-01-01

    The physical characterization of liposome, formulated from salicylic acid using thin film hydration methods with cholesterol and soybean lecithin, has been done. The formula was characterized by optical microscopes and Transmission Electron Microscope (TEM). The observation result shows that the salicylic acid can be formulated to liposomes. Soybean lecithin combined with cholesterol (600 mg : 20 mg) was the best formula and the liposome was spherical vesicle like with dimension about 70 nm unit 800 nm. (author)

  1. Atomic Force Microscopy Study on the Stiffness of Nanosized Liposomes Containing Charged Lipids.

    Science.gov (United States)

    Takechi-Haraya, Yuki; Goda, Yukihiro; Sakai-Kato, Kumiko

    2018-06-18

    It has recently been recognized that the mechanical properties of lipid nanoparticles play an important role during in vitro and in vivo behaviors such as cellular uptake, blood circulation, and biodistribution. However, there have been no quantitative investigations of the effect of commonly used charged lipids on the stiffness of nanosized liposomes. In this study, by means of atomic force microscopy (AFM), we quantified the stiffness of nanosized liposomes composed of neutrally charged lipids combined with positively or negatively charged lipids while simultaneously imaging the liposomes in aqueous medium. Our results showed that charged lipids, whether negatively or positively charged, have the effect of reducing the stiffness of nanosized liposomes, independently of the saturation degree of the lipid acyl chains; the measured stiffness values of liposomes containing charged lipids are 30-60% lower than those of their neutral counterpart liposomes. In addition, we demonstrated that the Laurdan generalized polarization values, which are related to the hydration degree of the liposomal membrane interface and often used as a qualitative indicator of liposomal membrane stiffness, do not directly correlate with the physical stiffness values of the liposomes prepared in this study. However, our results indicate that direct quantitative AFM measurement is a valuable method to gain molecular-scale information about how the hydration degree of liposomal interfaces reflects (or does not reflect) liposome stiffness as a macroscopic property. Our AFM method will contribute to the quantitative characterization of the nano-bio interaction of nanoparticles and to the optimization of the lipid composition of liposomes for clinical use.

  2. 6-mercaptopurine and daunorubicin double drug liposomes-preparation, drug-drug interaction and characterization.

    Science.gov (United States)

    Agrawal, Vineet; Paul, Manash K; Mukhopadhyay, Anup K

    2005-01-01

    This article addresses and investigates the dual incorporation of daunorubicin (DR) and 6-mercaptopurine (6-MP) in liposomes for better chemotherapy. These drugs are potential candidates for interaction due to the quinone (H acceptor) and hydroxyl (H donor) groups on DR and 6-MP, respectively. Interactions between the two drugs in solution were monitored by UV/Vis and fluorescence spectroscopy. Interaction between the two drugs inside the liposomes was evaluated by HPLC (for 6-MP) and by fluorescence spectroscopy (for daunorubicin) after phospholipase-mediated liposome lysis. Our results provide evidence for the lack of interaction between the two drugs in solution and in liposomes. The entrapment efficiencies of 6-MP in the neutral Phosphatidyl choline (PC):Cholesterol (Chol):: 2:1 and anionic PC:Chol:Cardiolipin (CL) :: 4:5:1 single and double drug liposomes were found to be 0.4% and 1.5% (on average), respectively. The entrapment efficiencies of DR in the neutral and anionic double drug liposomes were found to be 55% and 31%, respectively. The corresponding entrapment of daunorubicin in the single drug liposomes was found to be 62% on average. Our thin layer chromatography (TLC) and transmission electron microscopy (TEM) results suggest stability of lipid and liposomes, thus pointing plausible existence of double drug liposomes. Cytotoxicity experiments were performed by using both single drug and double drug liposomes. By comparing the results of phase contrast and fluorescence microscopy, it was observed that the double drug liposomes were internalized in the jurkat and Hut78 (highly resistant cell line) leukemia cells as viewed by the fluorescence of daunorubicin. The cytotoxicity was dose dependent and had shown a synergistic effect when double drug liposome was used.

  3. Sustained release of verapamil hydrochloride from sodium alginate microcapsules.

    Science.gov (United States)

    Farhana, S Ayesha; Shantakumar, S M; Shyale, Somashekar; Shalam, Md; Narasu, Laxmi

    2010-04-01

    The objective of the present study was to develop sustained release microcapsules of verapamil hydrochloride (VH) using biodegradable polymers. For this purpose microcapsules embedded verapamil hydrochloride were prepared using sodium alginate alone and also by incorporating some co polymers like methyl cellulose (MC), sodium carboxy methyl cellulose (SCMC) , poly vinyl pyrollidone (PVP) and xanthan gum by employing complex emulsion method of microencapsulation. Microcapsules were prepared in various core: coat ratios to know the effect of polymer and co polymers on drug release. Overall ten formulations were prepared and evaluated for flow behaviour, sieve analysis, drug entrapment efficiency, in vitro dissolution studies, stability studies, including scanning electron microscopy and DSC. The resulting microcapsules were discrete, large, spherical and also free flowing. The drug content in all the batches of microcapsules was found to be uniform. The release was depended on core: coat ratio and nature of the polymers. FTIR analysis revealed chemical integrity between Verapamil hydrochloride (VH), sodium alginate and between the copolymers. Among the four copolymers used methyl cellulose retarded the drug release more than the other three, hence the same formulation was subjected for in vivo studies. The drug release from the microcapsules was found to be following non fickian diffusion. Mechanism of drug release was diffusion controlled first order kinetics. Drug diffusion co efficient and correlation co efficient were also assessed by using various mathematical models. In vivo result analysis of pharmacokinetic parameters revealed that t max of reference and test formulations were almost same. From the study it was concluded that, sustained release Verapamil hydro chloride microcapsules could be achieved with success using sodium alginate alone and also in combination with other biodegradable polymers.

  4. Neuroprotection against vascular dementia after acupuncture combined with donepezil hydrochloride: P300 event related potential

    Directory of Open Access Journals (Sweden)

    Qiang Liu

    2016-01-01

    Full Text Available Acupuncture can be used to treat various nervous system diseases. Here, 168 vascular dementia patients were orally administered donepezil hydrochloride alone (5 mg/day, once a day for 56 days, or combined with acupuncture at Shenting (DU24, Tianzhu (BL10, Sishencong (Extra, Yintang (Extra, Renzhong (DU26, Neiguan (PC6, Shenmen (HT7, Fengchi (GB20, Wangu (GB12 and Baihui (DU20 (once a day for 56 days. Compared with donepezil hydrochloride alone, P300 event related potential latency was shorter with an increased amplitude in patients treated with donepezil hydrochloride and acupuncture. Mini-Mental State Examination score was also higher. Moreover, these differences in P300 latency were identified within different infarcted regions in patients treated with donepezil hydrochloride and acupuncture. These findings indicate that acupuncture combined with donepezil hydrochloride noticeably improves cognitive function in patients with vascular dementia, and exerts neuroprotective effects against vascular dementia.

  5. Atovaquone and proguanil hydrochloride: a review of nonclinical studies.

    Science.gov (United States)

    Pudney, M; Gutteridge, W; Zeman, A; Dickins, M; Woolley, J L

    1999-05-01

    Safe and effective antimalarial drugs are needed for treatment and prophylaxis of malaria. The combination of atovaquone and proguanil hydrochloride is a new antimalarial drug combination that has recently become available in many countries. Data were reviewed from nonclinical studies evaluating the microbiology, secondary pharmacology, pharmacokinetics, and toxicology of atovaquone and proguanil hydrochloride. Atovaquone is highly active against asexual erythrocytic stages of Plasmodium falciparum in vitro (IC50 0.7-6 nM) and in animal models. Proguanil per se has only weak antimalarial activity in vitro (IC50 2.4-19 microM), and its effectiveness depends on the active metabolite cycloguanil (IC50 0.5-2.5 nM). The combination of atovaquone and proguanil is synergistic in vitro. Both drugs also have activity against gametocytes and pre-erythrocytic (hepatic) stages of malaria parasites. Atovaquone is a ubiquinone antagonist that inhibits mitochondrial electron transport and collapses mitochondrial membrane potential. The proguanil metabolite cycloguanil is a dihydrofolate reductase inhibitor, but the mode of action of proguanil is unknown. In screening evaluations of secondary pharmacology, neither atovaquone nor proguanil had activity that adversely affected gastrointestinal, cardiovascular, or central or autonomic nervous system functions at clinically relevant concentrations. After oral administration, atovaquone exposure is extensive in rats but limited in dogs, while proguanil and cycloguanil exposure is extensive in dogs but limited in rats. In both species, toxicity was related to proguanil exposure, the principal manifestations being salivation, emesis, and loss of body weight. Neither atovaquone nor proguanil was teratogenic or mutagenic. An increased incidence of hepatic adenomas and adenocarcinomas was seen in mice, but not rats, after lifetime exposure to atovaquone, and appears to be related to species-specific differences in hepatic enzymatic activity

  6. [Clinical effect of atomoxetine hydrochloride in 66 children with narcolepsy].

    Science.gov (United States)

    Zhang, Shen; Ding, Changhong; Wu, Husheng; Fang, Fang; Wang, Xiaohui; Ren, Xiaotun

    2015-10-01

    To observe the efficacy and safety of atomoxetine hydrochloride in children with narcolepsy. Totally 66 patients with narcolepsy who were conformed international classification of sleep disturbances (ICSD-2) diagnostic criteria treated with atomoxetine hydrochloride seen from November 2010 to December 2014 were enrolled into this study, 42 of them were male and 24 female, mean age of onset was 7.5 years (3.75-13.00 years), mean duration before diagnosis was 1.75 years (0.25-5.00 years). Complete blood count, liver and kidney function, multiple sleep latency test (MSLT), polysomnography (PGS), neuroimaging and electroencephalography (EEG) were performed for each patient. For some of the children HLA-DR2 gene and serum markers of infection were tested. The 66 cases were followed up from 2 to 49 months (average 18 months) to observe the clinical efficacy and adverse reactions. In 62 cases excessive daytime sleepiness was improved, in 11 cases (16.7%) it was controlled (16.7%), in 29 cases (43.9%) the treatment was obviously effective and in 22 (33.3%) it was effective; cataplexy occurred in 54 cases, in 18 (33.3%) it was controlled, in 19 (35.2%) the treatment was obviously effective and in 10 (18.5%) effective; night sleep disorders existed in 55 cases, in 47 cases it was improved, in 14 (25.5%) it was controlled, in 20 (36.4%) the treatment was obviously effective and in 13 (23.6%) effective; hypnagogic or hypnopompic hallucination was present in 13 cases, in only 4 these symptoms were controlled. Sleep paralysis existed in 4 cases, it was controlled in only 1 case. In 18 cases attention and learning efficiency improved.Anorexia occurred in 18 cases, mood disorder in 5 cases, depression in 2 cases, nocturia, muscle tremors, involuntary tongue movement each occurred in 1 case. P-R interval prolongation and atrial premature contraction were found in 1 case. Atomoxetine hydrochloride showed good effects in patients with narcolepsy on excessive daytime sleepiness

  7. Nanoparticle-stabilized liposomes for pH-responsive gastric drug delivery.

    Science.gov (United States)

    Thamphiwatana, Soracha; Fu, Victoria; Zhu, Jingying; Lu, Diannan; Gao, Weiwei; Zhang, Liangfang

    2013-10-01

    We report a novel pH-responsive gold nanoparticle-stabilized liposome system for gastric antimicrobial delivery. By adsorbing small chitosan-modified gold nanoparticles (diameter ~10 nm) onto the outer surface of negatively charged phospholipid liposomes (diameter ~75 nm), we show that at gastric pH the liposomes have excellent stability with limited fusion ability and negligible cargo releases. However, when the stabilized liposomes are present in an environment with neutral pH, the gold stabilizers detach from the liposomes, resulting in free liposomes that can actively fuse with bacterial membranes. Using Helicobacter pylori as a model bacterium and doxycycline as a model antibiotic, we demonstrate such pH-responsive fusion activity and drug release profile of the nanoparticle-stabilized liposomes. Particularly, at neutral pH the gold nanoparticles detach, and thus the doxycycline-loaded liposomes rapidly fuse with bacteria and cause superior bactericidal efficacy as compared to the free doxycycline counterpart. Our results suggest that the reported liposome system holds a substantial potential for gastric drug delivery; it remains inactive (stable) in the stomach lumen but actively interacts with bacteria once it reaches the mucus layer of the stomach where the bacteria may reside.

  8. Mechanistic Studies on the Triggered Release of Liposomal Contents by Matrix Metalloproteinase-9

    Science.gov (United States)

    Elegbede, Adekunle I.; Banerjee, Jayati; Hanson, Andrea J.; Tobwala, Shakila; Ganguli, Bratati; Wang, Rongying; Lu, Xiaoning; Srivastava, D. K.; Mallik, Sanku

    2009-01-01

    Matrix metalloproteinases (MMPs) are a class of extracellular matrix degrading enzymes over-expressed in many cancers and contribute to the metastatic ability of the cancer cells. We have recently demonstrated that liposomal contents can be released when triggered by the enzyme MMP-9. Herein, we report our results on the mechanistic studies of the MMP-9 triggered release of the liposomal contents. We synthesized peptides containing the cleavage site for MMP-9 and conjugated them with fatty acids to prepare the corresponding lipopeptides. By employing Circular Dichroism spectroscopy, we demonstrate that the lipopeptides, when incorporated in liposomes, are de-mixed in the lipid bilayers and generate triple helical structures. MMP-9 cleaves the triple helical peptides, leading to the release of the liposomal contents. Other MMPs, which cannot hydrolyze triple helical peptides, failed to release the contents from the liposomes. We also observed that the rate and the extent of release of the liposomal contents depend on the mismatch between acyl chains of the synthesized lipopeptide and phospholipid components of the liposomes. Circular Dichroism spectroscopic studies imply that the observed differences in the release reflect the ability of the liposomal membrane to anneal the defects following the enzymatic cleavage of the liposome-incorporated lipopeptides. PMID:18642903

  9. Release of Liposomal Contents by Cell-Secreted Matrix Metalloproteinase-9

    Science.gov (United States)

    Banerjee, Jayati; Hanson, Andrea J.; Gadam, Bhushan; Elegbede, Adekunle I.; Tobwala, Shakila; Ganguly, Bratati; Wagh, Anil; Muhonen, Wallace W.; Law, Benedict; Shabb, John B.; Srivastava, D. K.; Mallik, Sanku

    2011-01-01

    Liposomes have been widely used as a drug delivery vehicle and currently, more than 10 liposomal formulations are approved by the Food and Drug Administration for clinical use. However, upon targeting, the release of the liposome-encapsulated contents is usually slow. We have recently demonstrated that contents from appropriately-formulated liposomes can be rapidly released by the cancer-associated enzyme matrix metalloproteinase-9 (MMP-9). Herein, we report our detailed studies to optimize the liposomal formulations. By properly selecting the lipopeptide, the major lipid component and their relative amounts, we demonstrate that the contents are rapidly released in the presence of cancer-associated levels of recombinant human MMP-9. We observed that the degree of lipid mismatch between the lipopepides and the major lipid component profoundly affects the release profiles from the liposomes. By utilizing the optimized liposomal formulations, we also demonstrate that cancer cells (HT-29) which secrete low levels of MMP-9 failed to release significant amount of the liposomal contents. Metastatic cancer cells (MCF7) secreting high levels of the enzyme rapidly release the encapsulated contents from the liposomes. PMID:19601658

  10. Physical and Oxidative Stability of Uncoated and Chitosan-Coated Liposomes Containing Grape Seed Extract

    Directory of Open Access Journals (Sweden)

    Jochen Weiss

    2013-08-01

    Full Text Available Polyphenol-rich grape seed extract (0.1 w/w% was incorporated in liposomes (1 w/w% soy lecithin by high pressure homogenization (22,500 psi and coated with chitosan (0.1 w/w%. Primary liposomes and chitosan-coated secondary liposomes containing grape seed extract showed good physical stability during 98 days of storage. Most of the polyphenols were incorporated in the shell of the liposomes (85.4%, whereas only 7.6% of the polyphenols of grape seed extract were located in the interior of the liposomes. Coating with chitosan did not change the polyphenol content in the liposomes (86.6%. The uncoated liposomes without grape seed extract were highly prone to lipid oxidation. The cationic chitosan coating, however, improved the oxidative stability to some extent, due to its ability to repel pro-oxidant metals. Encapsulated grape seed extract showed high antioxidant activity in both primary and secondary liposomes, which may be attributed to its polyphenol content. In conclusion, the best chemical stability of liposomes can be achieved using a combination of grape seed extract and chitosan.

  11. Modeling the Release Kinetics of Poorly Water-Soluble Drug Molecules from Liposomal Nanocarriers

    Directory of Open Access Journals (Sweden)

    Stephan Loew

    2011-01-01

    Full Text Available Liposomes are frequently used as pharmaceutical nanocarriers to deliver poorly water-soluble drugs such as temoporfin, cyclosporine A, amphotericin B, and paclitaxel to their target site. Optimal drug delivery depends on understanding the release kinetics of the drug molecules from the host liposomes during the journey to the target site and at the target site. Transfer of drugs in model systems consisting of donor liposomes and acceptor liposomes is known from experimental work to typically exhibit a first-order kinetics with a simple exponential behavior. In some cases, a fast component in the initial transfer is present, in other cases the transfer is sigmoidal. We present and analyze a theoretical model for the transfer that accounts for two physical mechanisms, collisions between liposomes and diffusion of the drug molecules through the aqueous phase. Starting with the detailed distribution of drug molecules among the individual liposomes, we specify the conditions that lead to an apparent first-order kinetic behavior. We also discuss possible implications on the transfer kinetics of (1 high drug loading of donor liposomes, (2 attractive interactions between drug molecules within the liposomes, and (3 slow transfer of drugs between the inner and outer leaflets of the liposomes.

  12. Optimization on Preparation Conditions of Salidroside Liposome and Its Immunological Activity on PCV-2 in Mice

    Directory of Open Access Journals (Sweden)

    Yibo Feng

    2015-01-01

    Full Text Available The aim of this study was to optimize the preparation conditions of salidroside liposome with high encapsulation efficiency (EE and to study the immunological enhancement activity of salidroside liposome as porcine circovirus type 2 virus (PCV-2 vaccine adjuvant. Response surface methodology (RSM was selected to optimize the conditions for the preparation of salidroside liposome using Design-Expert V8.0.6 software. Three kinds of salidroside liposome adjuvants were prepared to study their adjuvant activity. BALB/c mice were immunized with PCV-2 encapsulated in different kinds of salidroside liposome adjuvants. The PCV-2-specific IgG in immunized mice serum was determined with ELISA. The results showed that when the concentration of ammonium sulfate was 0.26 mol·L−1, ethanol volume 6.5 mL, temperature 43°C, ethanol injection rate 3 mL·min−1, and salidroside liposome could be prepared with high encapsulation efficiency of 94.527%. Salidroside liposome as adjuvant could rapidly induce the production of PCV-2-specific IgG and salidroside liposome I adjuvant proved to provide the best effect among the three kinds of salidroside liposome adjuvants.

  13. Thermo-responsive magnetic liposomes for hyperthermia-triggered local drug delivery.

    Science.gov (United States)

    Dai, Min; Wu, Cong; Fang, Hong-Ming; Li, Li; Yan, Jia-Bao; Zeng, Dan-Lin; Zou, Tao

    2017-06-01

    We prepared and characterised thermo-responsive magnetic liposomes, which were designed to combine features of magnetic targeting and thermo-responsive control release for hyperthermia-triggered local drug delivery. The particle size and zeta-potential of the thermo-responsive magnetic ammonium bicarbonate (MagABC) liposomes were about 210 nm and -14 mV, respectively. The MagABC liposomes showed encapsulation efficiencies of about 15% and 82% for magnetic nanoparticles (mean crystallite size 12 nm) and doxorubicin (DOX), respectively. The morphology of the MagABC liposomes was visualised using transmission electron microscope (TEM). The MagABC liposomes showed desired thermo-responsive release. The MagABC liposomes, when physically targeted to tumour cells in culture by a permanent magnetic field yielded a substantial increase in intracellular accumulation of DOX as compared to non-magnetic ammonium bicarbonate (ABC) liposomes. This resulted in a parallel increase in cytotoxicity for DOX loaded MagABC liposomes over DOX loaded ABC liposomes in tumour cells.

  14. Undulating tubular liposomes through incorporation of a synthetic skin ceramide into phospholipid bilayers.

    Science.gov (United States)

    Xu, Peng; Tan, Grace; Zhou, Jia; He, Jibao; Lawson, Louise B; McPherson, Gary L; John, Vijay T

    2009-09-15

    Nonspherical liposomes were prepared by doping L-alpha-phosphatidylcholine (PC) with ceramide VI (a skin lipid). Cryo-transmission electron microscopy shows the liposome shape changing from spherical to an undulating tubular morphology, when the amount of ceramide VI is increased. The formation of tubular liposomes is energetically favorable and is attributed to the association of ceramide VI with PC creating regions of lower curvature. Since ceramides are the major component of skin lipids in the stratum corneum, tubular liposomes containing ceramide may potentially serve as self-enhanced nanocarriers for transdermal delivery.

  15. Ultraviolet radiation-induced lipid peroxidation in liposomal membrane: modification by capsaicin

    Energy Technology Data Exchange (ETDEWEB)

    De, A. K.; Ghosh, J. J.; Mandal, T. K. [University College of Science, Department of Biochemistry, 35 Ballygunge Circular Road, Calcutta 700-019 (India)

    1993-07-01

    Ultraviolet-radiation has been reported to cause lipid peroxidation in the liposomal membrane. In the present study, treatment with capsaicin, (8-methyl-n-vanillyl-6-nonenamide), the pungent principle of red hot pepper, was shown to modify UV-induced lipid peroxidation in the liposomal membrane. Treatment with low doses of capsaicin (less than 0.1 μg/mL of phosphatidyl choline liposome) produced a significant increase in UV-induced lipid peroxidation, while high doses (0.1-0.5 μg/mL of PC liposome) caused a significant decrease of UV-induced peroxidation.

  16. Ultraviolet radiation-induced lipid peroxidation in liposomal membrane: modification by capsaicin

    International Nuclear Information System (INIS)

    De, A.K.; Ghosh, J.J.; Mandal, T.K.

    1993-01-01

    Ultraviolet-radiation has been reported to cause lipid peroxidation in the liposomal membrane. In the present study, treatment with capsaicin, (8-methyl-n-vanillyl-6-nonenamide), the pungent principle of red hot pepper, was shown to modify UV-induced lipid peroxidation in the liposomal membrane. Treatment with low doses of capsaicin (less than 0.1 μg/mL of phosphatidyl choline liposome) produced a significant increase in UV-induced lipid peroxidation, while high doses (0.1-0.5 μg/mL of PC liposome) caused a significant decrease of UV-induced peroxidation

  17. Development of a DNA-liposome complex for gene delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Rasoulianboroujeni, M. [Marquette University School of Dentistry, Milwaukee, WI 53233 (United States); Kupgan, G. [Department of Chemical Engineering, Oklahoma State University, 423 Engineering North, Stillwater, OK 74078 (United States); Moghadam, F. [School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ (United States); Tahriri, M. [Marquette University School of Dentistry, Milwaukee, WI 53233 (United States); Boughdachi, A. [Polymer Engineering Department, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Khoshkenar, P. [Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605 (United States); Ambrose, J.J. [Biomedical Engineering Department, Louisiana Tech University, Ruston, LA 71272 (United States); Kiaie, N. [Tissue Engineering Department, Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Vashaee, D. [Electrical and Computer Engineering Department, North Carolina State University, Raleigh, NC 27606 (United States); Ramsey, J.D. [Department of Chemical Engineering, Oklahoma State University, 423 Engineering North, Stillwater, OK 74078 (United States); Tayebi, L., E-mail: lobat.tayebi@marquette.edu [Marquette University School of Dentistry, Milwaukee, WI 53233 (United States)

    2017-06-01

    The association structures formed by cationic liposomes and DNA (Deoxyribonucleic acid)-liposome have been effectively utilized as gene carriers in transfection assays. In this research study, cationic liposomes were prepared using a modified lipid film hydration method consisting of a lyophilization step for gene delivery applications. The obtained results demonstrated that the mean particle size had no significant change while the polydispersity (PDI) increased after lyophilization. The mean particle size slightly reduced after lyophilization (520 ± 12 nm to 464 ± 25 nm) while the PDI increased after lyophilization (0.094 ± 0.017 to 0.220 ± 0.004). In addition. The mean particle size of vesicles increases when DNA is incorporated to the liposomes (673 ± 27 nm). According to the Scanning Electron Microscopy (SEM) and transmission electron microscopy (TEM) images, the spherical shape of liposomes confirmed their successful preservation and reconstitution from the powder. It was found that liposomal formulation has enhanced transfection considerably compared to the naked DNA as negative control. Finally, liposomal formulation in this research had a better function than Lipofectamine® 2000 as a commercialized product because the cellular activity (cellular protein) was higher in the prepared lipoplex than Lipofectamine® 2000. - Highlights: • Liposomal formulation in this research had a better function than Lipofectamine® 2000. • The average particle size had no significant change while the PDI increased after lyophilization. • LacZ expression of the developed cationic liposomes is approximately equal to the Lipofectamine® 2000.

  18. Ultrasound-mediated drug delivery using liposomes modified with a thermosensitive polymer.

    Science.gov (United States)

    Ninomiya, Kazuaki; Kawabata, Shinya; Tashita, Hiroyuki; Shimizu, Nobuaki

    2014-01-01

    Ultrasound-mediated drug delivery was established using liposomes that were modified with the thermosensitive polymer (TSP) poly(NIPMAM-co-NIPAM), which sensitized the liposomes to high temperatures. TSP-modified liposomes (TSP liposomes) released encapsulated calcein under 1 MHz ultrasound irradiation at 0.5 W/cm(2) for 120 s as well as the case under incubation at 42 °C for 15 min. In addition, uptake of the drug released from TSP liposomes by cancer cells was enhanced by ultrasound irradiation. In a cell injury assay using doxorubicin (DOX)-loaded TSP liposomes and ultrasound irradiation, cell viability of HepG2 cells at 6 h after ultrasound irradiation (1 MHz, 0.5 W/cm(2) for 30 s) with DOX-loaded TSP liposomes (TSP/lipid ratio=1) was 60%, which was significantly lower than that of the control conditions such as DOX-loaded TSP liposomes alone and DOX-loaded intact liposomes under ultrasound irradiation. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Biological Atomic Force Microscopy for Imaging Gold-Labeled Liposomes on Human Coronary Artery Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Ana-María Zaske

    2013-01-01

    Full Text Available Although atomic force microscopy (AFM has been used extensively to characterize cell membrane structure and cellular processes such as endocytosis and exocytosis, the corrugated surface of the cell membrane hinders the visualization of extracellular entities, such as liposomes, that may interact with the cell. To overcome this barrier, we used 90 nm nanogold particles to label FITC liposomes and monitor their endocytosis on human coronary artery endothelial cells (HCAECs in vitro. We were able to study the internalization process of gold-coupled liposomes on endothelial cells, by using AFM. We found that the gold-liposomes attached to the HCAEC cell membrane during the first 15–30 min of incubation, liposome cell internalization occurred from 30 to 60 min, and most of the gold-labeled liposomes had invaginated after 2 hr of incubation. Liposomal uptake took place most commonly at the periphery of the nuclear zone. Dynasore monohydrate, an inhibitor of endocytosis, obstructed the internalization of the gold-liposomes. This study showed the versatility of the AFM technique, combined with fluorescent microscopy, for investigating liposome uptake by endothelial cells. The 90 nm colloidal gold nanoparticles proved to be a noninvasive contrast agent that efficiently improves AFM imaging during the investigation of biological nanoprocesses.

  20. Preparation, characterization, and in vitro release study of albendazole-encapsulated nanosize liposomes

    Science.gov (United States)

    Panwar, Preety; Pandey, Bhumika; Lakhera, P C; Singh, K P

    2010-01-01

    The purpose of the present study was to formulate effective and controlled release albendazole liposomal formulations. Albendazole, a hydrophobic drug used for the treatment of hydatid cysts, was encapsulated in nanosize liposomes. Rapid evaporation method was used for the preparation of albendazole-encapsulated conventional and PEGylated liposomes consisting of egg phosphatidylcholine (PC) and cholesterol (CH) in the molar ratios of (6:4) and PC:CH: polyethylene glycol (PEG) (5:4:1), respectively. In this study, PEGylated and conventional liposomes containing albendazole were prepared and their characteristics, such as particle size, encapsulation efficiency, and in vitro drug release were investigated. The drug encapsulation efficiency of PEGylated and conventional liposomes was 81% and 72%, respectively. The biophysical characterization of both conventional and PEG-coated liposomes were done by transmission electron microscopy and UV-vis spectrophotometry. Efforts were made to study in vitro release of albendazole. The drug release rate showed decrease in albendazole release in descending order: free albendazole, albendazole-loaded conventional liposomes, and least with albendazole-loaded PEG-liposomes. Biologically relevant vesicles were prepared and in vitro release of liposome-entrapped albendazole was determined. PMID:20309396

  1. Aerosolized liposomes with dipalmitoyl phosphatidylcholine enhance pulmonary absorption of encapsulated insulin compared with co-administered insulin.

    Science.gov (United States)

    Chono, Sumio; Togami, Kohei; Itagaki, Shirou

    2017-11-01

    We have previously shown that aerosolized liposomes with dipalmitoyl phosphatidylcholine (DPPC) enhance the pulmonary absorption of encapsulated insulin. In this study, we aimed to compare insulin encapsulated into the liposomes versus co-administration of empty liposomes and unencapsulated free insulin, where the DPCC liposomes would serve as absorption enhancer. The present study provides the useful information for development of noninvasive treatment of diabetes. Co-administration of empty DPPC liposomes and unencapsulated free insulin was investigated in vivo to assess the potential enhancement in protein pulmonary absorption. Co-administration was compared to DPPC liposomes encapsulating insulin, and free insulin. DPPC liposomes enhanced the pulmonary absorption of unencapsulated free insulin; however, the enhancing effect was lower than that of the DPPC liposomes encapsulating insulin. The mechanism of the pulmonary absorption of unencapsulated free insulin by DPPC liposomes involved the opening of epithelial cell space in alveolar mucosa, and not mucosal cell damage, similar to that of the DPPC liposomes encapsulating insulin. In an in vitro stability test, insulin in the alveolar mucus layer that covers epithelial cells was stable. These findings suggest that, although unencapsulated free insulin spreads throughout the alveolar mucus layer, the concentration of insulin released near the absorption surface is increased by the encapsulation of insulin into DPPC liposomes and the absorption efficiency is also increased. We revealed that the encapsulation of insulin into DPPC liposomes is more effective for pulmonary insulin absorption than co-administration of DPPC liposomes and unencapsulated free insulin.

  2. Development of curcumin liposome formulations using polyol dilution method

    Directory of Open Access Journals (Sweden)

    Lalana Kongkaneramit

    2016-12-01

    Full Text Available This study was aimed to formulate curcumin liposomes (CLs by using polyol dilution method which is advantageous for no residue of organic solvent. CLs were the mixture of hydrogenated phosphatidylcholine (PC and cholesterol (CH at the molar ratio of 9:1. Propylene glycol (PG, glycerin, and polyethylene glycol 400 (PEG-400 were used as polyol solvent. Extrusion was applied after the suspension formed. The amount of polyol and curcumin and preparing temperature were investigated. The obtained suspensions were observed for appearance, size, size distribution, zeta potential, morphology, and percentage of entrapment. The results showed that type and amount of polyol had an impact on both liposomal size and the amount of entrapped curcumin, while preparing temperature was also an important factor. However, the solubility of lipids and drug in a given polyol should be considered because of loading efficiency in the formulation.

  3. Recurrent Candida albicans Ventriculitis Treated with Intraventricular Liposomal Amphotericin B

    Directory of Open Access Journals (Sweden)

    Demet Toprak

    2015-01-01

    Full Text Available Central nervous system (CNS infection with Candida is rare but significant because of its high morbidity and mortality. When present, it is commonly seen among immunocompromised and hospitalized patients. Herein, we describe a case of a four-year-old boy with acute lymphoblastic leukemia (ALL who experienced recurrent Candida albicans meningitis. The patient was treated successfully with intravenous liposomal amphotericin B at first attack, but 25 days after discharge he was readmitted to hospital with symptoms of meningitis. Candida albicans was grown in CFS culture again and cranial magnetic resonance imaging (MRI showed ventriculitis. We administered liposomal amphotericin B both intravenously and intraventricularly and favorable result was achieved without any adverse effects. Intraventricular amphotericin B may be considered for the treatment of recurrent CNS Candida infections in addition to intravenous administration.

  4. Lateral Tension-Induced Penetration of Particles into a Liposome

    Directory of Open Access Journals (Sweden)

    Kazuki Shigyou

    2017-07-01

    Full Text Available It is important that we understand the mechanism of the penetration of particles into a living cell to achieve advances in bionanotechnology, such as for treatment, visualization within a cell, and genetic modification. Although there have been many studies on the application of functional particles to cells, the basic mechanism of penetration across a biological membrane is still poorly understood. Here we used a model membrane system to demonstrate that lateral membrane tension drives particle penetration across a lipid bilayer. After the application of osmotic pressure, fully wrapped particles on a liposome surface were found to enter the liposome. We discuss the mechanism of the tension-induced penetration in terms of narrow constriction of the membrane at the neck part. The present findings are expected to provide insight into the application of particles to biological systems.

  5. Detection of antimycolic acid antibodies by liposomal biosensors

    CSIR Research Space (South Africa)

    Lemmer, Yolandy

    2009-01-01

    Full Text Available -mycolic acid antibodies by liposomal biosensors Running title: Antibody detection by liposomal biosensors Y. Lemmer1,3, S.T., Thanyani1, P.J. Vrey1, C.H.S. Driver2, L. Venter1, S. van Wyngaardt1, A.M.C. ten Bokum1, K.I. Ozoemena2, L.A. Pilcher2, D...H values. The anionic phosphatidyl residues (pKa ? 3.5) only become neutralised below pH 4, while the cationic state of choline (pKa = 13.9) is maintained over the full pH range measured (Tatulian et al., 1993). It is therefore expected that the stability...

  6. Development of Liposomal Ciprofloxacin to Treat Lung Infections

    Directory of Open Access Journals (Sweden)

    David Cipolla

    2016-03-01

    Full Text Available Except for management of Pseudomonas aeruginosa (PA in cystic fibrosis, there are no approved inhaled antibiotic treatments for any other diseases or for infections from other pathogenic microorganisms such as tuberculosis, non-tuberculous mycobacteria, fungal infections or potential inhaled biowarfare agents including Francisella tularensis, Yersinia pestis and Coxiella burnetii (which cause pneumonic tularemia, plague and Q fever, respectively. Delivery of an antibiotic formulation via the inhalation route has the potential to provide high concentrations at the site of infection with reduced systemic exposure to limit side effects. A liposomal formulation may improve tolerability, increase compliance by reducing the dosing frequency, and enhance penetration of biofilms and treatment of intracellular infections. Two liposomal ciprofloxacin formulations (Lipoquin® and Pulmaquin® that are in development by Aradigm Corporation are described here.

  7. Mucosal delivery of liposome-chitosan nanoparticles complexes

    OpenAIRE

    Carvalho, Edison Samir Mascarelhas; Grenha, Ana; Remuñán-López, Carmen; Alonso, Maria José; Seijo, Begoña

    2009-01-01

    Designing adequate drug carriers has long been a major challenge for those working in drug delivery. Since drug delivery strategies have evolved for mucosal delivery as the outstanding alternative to parenteral administration, many new drug delivery systems have been developed which evidence promising properties to address specific issues. Colloidal carriers, such as nanoparticles and liposomes, have been referred to as the most valuable approaches, but still have some limitations that can...

  8. Formation of drug nanocrystals under nanoconfinement afforded by liposomes

    DEFF Research Database (Denmark)

    Cipolla, D.; Wu, H.; Salentinig, Stefan

    2016-01-01

    Nanocrystals of drug substances have important therapeutic applications, but their preparation is often difficult due to size control in bottom up approaches, or energetic milling and surface activation in top down processing. In this study, confinement within liposome nanocompartments is demonst...... physical means (e.g., freeze/thaw) is an attractive possibility, especially in highly regulated industries such as pharmaceuticals where qualitative and quantitative changes of composition would require extensive safety evaluations....

  9. BODIPY-based fluorescent liposomes with sesquiterpene lactone trilobolide

    Czech Academy of Sciences Publication Activity Database

    Škorpilová, Ludmila; Rimpelová, S.; Jurášek, M.; Buděšínský, Miloš; Lokajová, Jana; Effenberg, R.; Slepička, P.; Ruml, T.; Kmoníčková, Eva; Drašar, P. B.; Wimmer, Zdeněk

    2017-01-01

    Roč. 13, JUL 4 (2017), s. 1316-1324 ISSN 1860-5397 R&D Projects: GA MŠk LD15012; GA MŠk(CZ) LO1304 Institutional support: RVO:61389030 ; RVO:61388963 ; RVO:68378041 Keywords : BODIPY conjugates * Cancer targeting * Drug delivery * Liposomes * Natural compounds * Sesquiterpene lactone trilobolide Subject RIV: CC - Organic Chemistry ; FR - Pharmacology ; Medidal Chemistry (UEM-P) OBOR OECD: Organic chemistry ; Pharmacology and pharmacy (UEM-P) Impact factor: 2.337, year: 2016

  10. Preparation and Use of Liposomes in Immunological Studies

    Science.gov (United States)

    1993-01-01

    using any serum, whether antiserum or complement. the serum must be extensively dialyzed to remove endogenous glucose. For complement we routinely...release method when compared to other liposome lysis assays is the presence of high levels of endogenous glucose in all sera, and frequently even in...Native lipid A from S. minnesota R595 (List) and monophospho- rosryl lipid A (Ribi) were 214-fold and 25-fold less pyrogenic than free lipid Volume 111 337

  11. Effects of MK-467 hydrochloride and hyoscine butylbromide on cardiorespiratory and gastrointestinal changes induced by detomidine hydrochloride in horses.

    Science.gov (United States)

    Tapio, Heidi A; Raekallio, Marja R; Mykkänen, Anna; Mama, Khursheed; Mendez-Angulo, Jóse L; Hautajärvi, Heidi; Vainio, Outi M

    2018-04-01

    OBJECTIVE To compare the effects of MK-467 and hyoscine butylbromide on detomidine hydrochloride-induced cardiorespiratory and gastrointestinal changes in horses. ANIMALS 6 healthy adult horses. PROCEDURES Horses received detomidine hydrochloride (20 μg/kg, IV), followed 10 minutes later by MK-467 hydrochloride (150 μg/kg; DET-MK), hyoscine butylbromide (0.2 mg/kg; DET-HYO), or saline (0.9% NaCl) solution (DET-S), IV, in a Latin square design. Heart rate, respiratory rate, rectal temperature, arterial and venous blood pressures, and cardiac output were measured; blood gases and arterial plasma drug concentrations were analyzed; selected cardiopulmonary variables were calculated; and sedation and gastrointestinal borborygmi were scored at predetermined time points. Differences among treatments or within treatments over time were analyzed statistically. RESULTS With DET-MK, detomidine-induced hypertension and bradycardia were reversed shortly after MK-467 injection. Marked tachycardia and hypertension were observed with DET-HYO. Mean heart rate and mean arterial blood pressure differed significantly among all treatments from 15 to 35 and 15 to 40 minutes after detomidine injection, respectively. Cardiac output was greater with DET-MK and DET-HYO than with DET-S 15 minutes after detomidine injection, but left ventricular workload was significantly higher with DET-HYO. Borborygmus score, reduced with all treatments, was most rapidly restored with DET-MK. Sedation scores and pharmacokinetic parameters of detomidine did not differ between DET-S and DET-MK. CONCLUSIONS AND CLINICAL RELEVANCE MK-467 reversed or attenuated cardiovascular and gastrointestinal effects of detomidine without notable adverse effects or alterations in detomidine-induced sedation in horses. Further research is needed to determine whether these advantages are found in clinical patients and to assess whether the drug influences analgesic effects of detomidine.

  12. Mucosal delivery of liposome-chitosan nanoparticle complexes.

    Science.gov (United States)

    Carvalho, Edison L S; Grenha, Ana; Remuñán-López, Carmen; Alonso, Maria José; Seijo, Begoña

    2009-01-01

    Designing adequate drug carriers has long been a major challenge for those working in drug delivery. Since drug delivery strategies have evolved for mucosal delivery as the outstanding alternative to parenteral administration, many new drug delivery systems have been developed which evidence promising properties to address specific issues. Colloidal carriers, such as nanoparticles and liposomes, have been referred to as the most valuable approaches, but still have some limitations that can become more inconvenient as a function of the specific characteristics of administration routes. To overcome these limitations, we developed a new drug delivery system that results from the combination of chitosan nanoparticles and liposomes, in an approach of combining their advantages, while avoiding their individual limitations. These lipid/chitosan nanoparticle complexes are, thus, expected to protect the encapsulated drug from harsh environmental conditions, while concomitantly providing its controlled release. To prepare these assemblies, two different strategies have been applied: one focusing on the simple hydration of a previously formed dry lipid film with a suspension of chitosan nanoparticles, and the other relying on the lyophilization of both basic structures (nanoparticles and liposomes) with a subsequent step of hydration with water. The developed systems are able to provide a controlled release of the encapsulated model peptide, insulin, evidencing release profiles that are dependent on their lipid composition. Moreover, satisfactory in vivo results have been obtained, confirming the potential of these newly developed drug delivery systems as drug carriers through distinct mucosal routes.

  13. Liposome-Based Delivery Systems in Plant Polysaccharides

    International Nuclear Information System (INIS)

    Meiwan, C.; Yitao, W.; Yanfang, Z.; Xinsheng, P.; Jingjing, H.; Ping, Z.

    2012-01-01

    Plant polysaccharides consist of many monosaccharide by α or β glycosidic bond which can be extracted by the water, alcohol, lipophile liquid from a variety of plants including Cordyceps sinensis, astragalus, and mushrooms. Recently, many evidences illustrate that natural plant polysaccharides possess various biological activities including strengthening immunity, lowering blood sugar, regulating lipid metabolism, anti oxidation, anti aging, and antitumour. Plant polysaccharides have been widely used in the medical field due to their special features and low toxicity. As an important drug delivery system, liposomes can not only encapsulate small-molecule compound but also big-molecule drug; therefore, they present great promise for the application of plant polysaccharides with unique physical and chemical properties and make remarkable successes. This paper summarized the current progress in plant polysaccharides liposomes, gave an overview on their experiment design method, preparation, and formulation, characterization and quality control, as well as in vivo and in vitro studies. Moreover, the potential application of plant polysaccharides liposomes was prospected as well.

  14. Integration of β-carotene molecules in small liposomes

    International Nuclear Information System (INIS)

    Andreeva, Atanaska; Popova, Antoaneta

    2010-01-01

    The most typical feature of carotenoids is the long polyene chain with conjugated double bonds suggesting that they can serve as conductors of electrons, acting as 'molecular wires', important elements in the molecular electronic devices. Carotenoids are essential components of photosynthetic systems, performing different functions as light harvesting, photoprotection and electron transfer. They act also as natural antioxidants. In addition they perform structural role stabilizing the three-dimensional organization of photosynthetic membranes. Carotenoids contribute to the stability of the lipid phase, preserving the membrane integrity under potentially harmful environmental conditions. Carotenoids can be easily integrated into model membranes, facilitating the investigation of their functional roles. In carotenoid-egg phosphatidylcholine (EPC) liposomes ss-carotene is randomly distributed in the hydrocarbon interior of the bilayer, without any preferred, well defined orientation and retains a substantial degree of mobility. Here we investigate the degree of integration of ss-carotene in small unilamellar EPC liposomes and the changes in ss-carotene absorption and Raman spectra due to the lipid-pigment interaction. All observed changes in ss-carotene absorption and Raman spectra may be regarded as a result of the lipid-pigment interactions leading to the polyene geometry distortion and increasing of the environment heterogenety in the liposomes as compared to the solutions.

  15. In vivo hypertensive arterial wall uptake of radiolabeled liposomes

    International Nuclear Information System (INIS)

    Hodis, H.N.; Amartey, J.K.; Crawford, D.W.; Wickham, E.; Blankenhorn, D.H.

    1990-01-01

    Using five sham-operated and seven aortic coarctation-induced hypertensive New Zealand White rabbits intravenously injected with neutral small unilamellar vesicles loaded with [111In]nitrilotriacetic acid, we demonstrated in vivo that the normal aortic arterial wall participates in liposome uptake and that this uptake is increased in the hypertensive aortic wall by approximately threefold (p less than or equal to 0.0001). Among the three regions examined, aortic arch, thoracic aorta, and lower abdominal aorta, the difference in uptake between the normotensive and hypertensive arterial walls was significantly different, p less than or equal to 0.05, p less than or equal to 0.0001, and p less than 0.05, respectively. The uptake by the different regions of the hypertensive arterial wall is consistent with the pathological changes present in these areas. Furthermore, the extent of liposome uptake by the aortic wall is strongly correlated with the height of the blood pressure (r = 0.85, p = 0.001, n = 11). We conclude that neutral small unilamellar liposomes can be used to carry agents into the arterial wall in vivo in the study of hypertensive vascular disease and could be especially useful for the delivery of pharmacologically or biologically active agents that would otherwise be inactivated within the circulation or are impermeable to the arterial wall

  16. Thermosensitive liposomes entrapping iron oxide nanoparticles for controllable drug release

    International Nuclear Information System (INIS)

    Tai, L-A; Wang, Y-C; Wang, Y-J; Yang, C-S; Tsai, P-J; Lo, L-W

    2009-01-01

    Iron oxide nanoparticles can serve as a heating source upon alternative magnetic field (AMF) exposure. Iron oxide nanoparticles can be mixed with thermosensitive nanovehicles for hyperthermia-induced drug release, yet such a design and mechanism may not be suitable for controllable drug release applications in which the tissues are susceptible to environmental temperature change such as brain tissue. In the present study, iron oxide nanoparticles were entrapped inside of thermosensitive liposomes for AMF-induced drug release while the environmental temperature was maintained at a constant level. Carboxyfluorescein was co-entrapped with the iron oxide nanoparticles in the liposomes as a model compound for monitoring drug release and environmental temperature was maintained with a water circulator jacket. These experiments have been successfully performed in solution, in phantom and in anesthetized animals. Furthermore, the thermosensitive liposomes were administered into rat forearm skeletal muscle, and the release of carboxylfluorescein triggered by the external alternative magnetic field was monitored by an implanted microdialysis perfusion probe with an on-line laser-induced fluorescence detector. In the future such a device could be applied to simultaneous magnetic resonance imaging and non-invasive drug release in temperature-sensitive applications.

  17. Enhanced bactericidal potency of nanoliposomes by modification of the fusion activity between liposomes and bacterium

    Directory of Open Access Journals (Sweden)

    Ma YF

    2013-06-01

    Full Text Available Yufan Ma,1 Zhao Wang,1,2 Wen Zhao,1 Tingli Lu,1 Rutao Wang,1,2 Qibing Mei,1 Tao Chen1–3 1Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, People's Republic of China; 2Shaanxi Liposome Research Center, Xi'an, Shaanxi, People's Republic of China; 3Xi'an Libang Pharmaceuticals Co, Ltd, Xi'an, People's Republic of China Background: Pseudomonas aeruginosa represents a good model of antibiotic resistance. These organisms have an outer membrane with a low level of permeability to drugs that is often combined with multidrug efflux pumps, enzymatic inactivation of the drug, or alteration of its molecular target. The acute and growing problem of antibiotic resistance of Pseudomonas to conventional antibiotics made it imperative to develop new liposome formulations to overcome these mechanisms, and investigate the fusion between liposome and bacterium. Methods: The rigidity, stability and charge properties of phospholipid vesicles were modified by varying the cholesterol, 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE, and negatively charged lipids 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol sodium salt (DMPG, 1,2-dimyristoyl-sn-glycero-3-phopho-L-serine sodium salt (DMPS, 1,2-dimyristoyl-sn-glycero-3-phosphate monosodium salt (DMPA, nature phosphatidylserine sodium salt from brain and nature phosphatidylinositol sodium salt from soybean concentrations in liposomes. Liposomal fusion with intact bacteria was monitored using a lipid-mixing assay. Results: It was discovered that the fluid liposomes-bacterium fusion is not dependent on liposomal size and lamellarity. A similar degree of fusion was observed for liposomes with a particle size from 100 to 800 nm. The fluidity of liposomes is an essential pre-request for liposomes fusion with bacteria. Fusion was almost completely inhibited by incorporation of cholesterol into fluid liposomes. The increase in the

  18. Effective in vitro and in vivo gene delivery by the combination of liposomal bubbles (bubble liposomes) and ultrasound exposure.

    Science.gov (United States)

    Suzuki, Ryo; Maruyama, Kazuo

    2010-01-01

    Gene delivery with a physical mechanism using ultrasound (US) and nano/microbubbles is expected as an ideal system in terms of delivering plasmid DNA noninvasively into a specific target site. We developed novel liposomal bubbles (Bubble liposomes (BLs)) containing the lipid nanobubbles of perfluoropropane which were utilized for contrast enhancement in ultrasonography. BLs were smaller in diameter than conventional microbubbles and induced cavitation upon exposure ultrasound. In addition, when coupled with US exposure, BLs could deliver plasmid DNA into various types of cells in vitro and in vivo. The transfection efficiency with BLs and US was higher than that with conventional lipofection method. Therefore, the combination of BLs and US might be an efficient and novel nonviral gene delivery system.

  19. Exploiting the Metal-Chelating Properties of the Drug Cargo for In Vivo Positron Emission Tomography Imaging of Liposomal Nanomedicines

    DEFF Research Database (Denmark)

    Edmonds, Scott; Volpe, Alessia; Shmeeda, Hilary

    2016-01-01

    of a radiolabeled stealth liposomal nanomedicine containing alendronate that shows high uptake in primary tumors and metastatic organs. The versatility, efficiency, simplicity, and GMP compatibility of this method may enable submicrodosing imaging studies of liposomal nanomedicines containing chelating drugs...

  20. Ciprofloxacin in polyethylene glycol-coated liposomes: efficacy in rat models of acute or chronic Pseudomonas aeruginosa infection

    NARCIS (Netherlands)

    I.A.J.M. Bakker-Woudenberg (Irma); M.T. ten Kate (Marian); L. Guo; P. Working; J.W. Mouton (Johan)

    2002-01-01

    textabstractIn a previous study in experimental Klebsiella pneumoniae pneumonia, the therapeutic potential of ciprofloxacin was significantly improved by encapsulation in polyethylene glycol-coated ("pegylated") long-circulating (STEALTH) liposomes. Pegylated liposomal

  1. Improved stability and antidiabetic potential of insulin containing folic acid functionalized polymer stabilized multilayered liposomes following oral administration

    DEFF Research Database (Denmark)

    Agrawal, Ashish Kumar; Harde, Harshad; Thanki, Kaushik

    2014-01-01

    The present study reports the folic acid (FA) functionalized insulin loaded stable liposomes with improved bioavailability following oral administration. Liposomes were stabilized by alternating coating of negatively charged poly(acrylic acid) (PAA) and positively charged poly(allyl amine...

  2. Preparation of liposomes containing zedoary turmeric oil using freeze-drying of liposomes via TBA/water cosolvent systems and evaluation of the bioavailability of the oil.

    Science.gov (United States)

    Yang, Zhiwen; Yu, Songlin; Fu, Dahua

    2010-02-01

    The purpose of this study was to enhance the absorption of zedoary turmeric oil (ZTO) in vivo and develop new formulations of a water-insoluble oily drug. This study described a method for preparing ZTO liposomes, which involved freeze-drying (FD) of liposomes with TBA/water cosolvent systems. The TBA/water cosolvent systems were used to investigate a feasible method of liposomes manufacture; the two factors, sugar/lipid mass ratio and TBA content (concentration), of the preparation process were evaluated in this study. The results showed that the addition of TBA content could significantly enhance the sublimation of ice resulting in short FD cycles time, and reduce the entrapment efficiency of liposomes. In addition, the residual TBA solvents levels were determined to be less than 0.37% under all optimum formulations and processing conditions. Several physical properties of liposomes were examined by H-600 transmission electron microscope (TEM) and zetamaster analyser system. The results revealed that the liposomes were smooth and spherical with an average particle size of 457 +/- 7.8 nm and the zeta potential was more than 3.65 Mv. The bioavailability of the liposomes was evaluated in rabbits, compared with the conventional self-emulsifying formulation for oral administration. Compared with the conventional self-emulsifying formulation, the plasma concentration-time profiles with improved sustained-release characteristics were achieved after oral administration of the liposomes with a bioavailability of 257.7% (a good strategy for improving the bioavailability of an oily drug). In conclusion, the present experimental findings clearly demonstrated the usefulness of ZTO liposome vesicles in improving therapeutic efficacy by enhancing oral bioavailability. Our study offered an alternative method for designing sustained-release preparations of oily drugs.

  3. SPECTROPHOTOMETRIC, ATOMIC ABSORPTION AND CONDUCTOMETRIC ANALYSIS OF TRAMADOL HYDROCHLORIDE

    Directory of Open Access Journals (Sweden)

    Sara M. Anis

    2011-09-01

    Full Text Available Six simple and sensitive spectroscopic and conductometric procedures (A-F were developed for the determination of tramadol hydrochloride. Methods A, B and C are based on the reaction of cobalt (II thiocyanate with tramadol to form a stable ternary complex, which could be measured by spectrophotometric (method A, atomic absorption (method B or conductometric (method C procedures. Methods D and E depend on the reaction of molybdenum thiocyanate with tramadol to form a stable ternary complex, measured by spectrophotometric means (method D or by atomic absorption procedures (method E, while method F depends on the formation of an ion pair complex between the studied drug and bromothymol blue which is extractable into methylene chloride. Tramadol hydrochloride could be assayed in the range of 80-560 and 40-–220 μg ml-1, 1-15 mg ml-1 and 2.5-22.5, 1.25-11.25 and 5-22 μg ml-1 using methods A,B,C,D,E and F, respectively. Various experimental conditions were studied. The results obtained showed good recoveries. The proposed procedures were applied successfully to the analysis of tramadol in its pharmaceutical preparations and the results were favorably comparable with the official method.

  4. Growth of glycine ethyl ester hydrochloride and its characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesan, G.; Pari, S., E-mail: sparimyur@gmail.com

    2016-11-15

    Single crystal of glycine ethyl ester hydrochloride by slow evaporation method is reported. The grown crystal characterized by single crystal X-ray diffraction, FT-IR, UV–Vis–NIR and fluorescence spectroscopy. It is established that the crystal falls under the monoclinic system and space group P21/c with the cell parameters as: a=8.565 Å, b=12.943 Å, c=6.272 Å, α=γ=90°, β=103.630º. UV–Vis–NIR spectrum shows indirect allowed transition with a band gap of 5.21 eV and other optical properties are measured. The crystal is also shown to have a high transmittance in the visible region. The third order nonlinear property and optical limiting have been investigated using Z-Scan technique. Complex impedance spectrum measured at the dc conductivity. Dependence of dielectric constant, dielectric loss and ac conductivity on frequency at different temperature of applied ac field is analyzed. The mechanical behavior has been assessed by Vickers microhardness indenter. The thermal behavior of glycine ethyl ester hydrochloride was analyzed using TG/DTA thermal curves. From the thermal study, the material was found to possess thermal stability up to 174 °C. The predicted NLO properties, UV–Vis transmittance and Z-scan studies indicate that is an attractive material for photonics optical limiting applications.

  5. Chemoreactomic analysis of thiamine disulfide, thiamine hydrochloride, and benfotiamine molecules

    Directory of Open Access Journals (Sweden)

    O. A. Gromova

    2017-01-01

    Full Text Available Objective: to analyze the interactions that could indicate the potential pharmacological properties of the molecules of thiamin, thiamine disulfide, and others.Material and methods. The investigators simulated the properties of thiamine disulfide (bistiamin versus those of the reference molecules of thiamin hydrochloride and benfotiamine. The study was performed using chemoreactomic simulation that is the newest area in post-genome pharmacology.Results and discussion. Chemoreactomic analysis has shown that thiamine disulfide can inhibit the molecular receptors involved in blood pressure regulation: adrenoceptors, vasopressin receptor, and angiotensin receptor. Thiamine disulfide can inhibit the reuptake of serotonin, increase its levels, inhibit benzodiazepine receptor and dopamine reuptake, and enhance neuronal acetylcholine release to a large extent than benfotiamine. These molecular effects are consistent with the sedative and anticonvulsant action profile of thiamine disulfide. Simulation has indicated that thiamine disulfide has neuroprotective, anti-inflammatory, normolipidemic, and antitumor activities.Conclusion. The simulation results are confirmed by the available clinical and experimental findings and indicate the virtually unstudied molecular mechanisms of action of thiamine disulfide, benfotiamine, and thiamin hydrochloride

  6. Oxymetazoline hydrochloride cream for facial erythema associated with rosacea.

    Science.gov (United States)

    Patel, Nupur U; Shukla, Shweta; Zaki, Jessica; Feldman, Steven R

    2017-10-01

    Rosacea is a chronic skin condition characterized by transient and persistent erythema of the central face. The symptom of persistent erythema can be particularly frustrating for both patients and physicians as it is difficult to treat. Areas covered: Current treatment options for the treatment of rosacea include metronidazole, azelaic acid, sodium sulfacetamide-sulfur, and brimonidine. Until recently, brimonidine gel was the only option approved specifically for the treatment of facial erythema. However, oxymetazoline hydrochloride 1% cream is a newly FDA approved topical medication for adult rosacea patients. A primarily alpha-1a agonist, oxymetazoline hydrochloride (HCl) is thought to diminish erythema through vasoconstriction. Our paper seeks to evaluate evidence for topical oxymetazoline HCl with respect to its efficacy and safety for its approved indication of treating the persistent erythema associated with rosacea. Expert commentary: While assessment of available clinical trial data indicates that the medication is as effective as other available treatment for controlling rosacea-associated erythema with minimal risk of adverse effects, studies of long-term duration and direct comparison will be necessary to establish its place in treatment guidelines and clinical practice. As further evidence becomes available, the real-world clinical potential of topical oxymetazoline cream will become clearer.

  7. Intestinal Anisakiasis Treated Successfully with Prednisolone and Olopatadine Hydrochloride

    Directory of Open Access Journals (Sweden)

    Hideki Toyoda

    2016-02-01

    Full Text Available The clinical characteristic of gastrointestinal anisakiasis is severe abdominal pain after eating raw fish. Intestinal anisakiasis is more uncommon than gastric anisakiasis. Most patients with intestinal anisakiasis need hospitalization because anisakiasis can cause intestinal obstruction, ileus, peritonitis or intestinal perforation. We report a case of intestinal anisakiasis. A 43-year-old woman presented with symptoms of intermittent abdominal pain 2 days after eating raw fish. Her brother had eaten the same food and had been suffering from gastric anisakiasis. Abdominal ultrasonography in this patient showed localized jejunal wall thickening with dilated lumen of proximal jejunum and ascites. According to the clinical course and examinations, she was diagnosed with intestinal anisakiasis. Administration of prednisolone 5 mg/day and olopatadine hydrochloride 10 mg/day improved her symptoms quickly without hospitalization. Prednisolone was administered for 10 days, and olopatadine hydrochloride was administered for a total of 6 weeks according to ultrasonographic findings. Six months after the treatment, the abdominal ultrasonography demonstrated normal findings. This case demonstrates that ultrasonography was quite useful for the diagnosis and surveillance of intestinal anisakiasis. Furthermore, treatment with corticosteroid and an antiallergic agent could be an option for patients with intestinal anisakiasis.

  8. Transepithelial transport of biperiden hydrochloride in Caco-2 cell monolayers.

    Science.gov (United States)

    Abalos, Ivana S; Rodríguez, Yanina I; Lozano, Verónica; Cereseto, Marina; Mussini, Maria V; Spinetto, Marta E; Chiale, Carlos; Pesce, Guido

    2012-09-01

    The aim of this research has been to determine the biperiden hydrochloride permeability in Caco-2 model, in order to classify it based on the Biopharmaceutics Classification System (BCS). The World Health Organization (WHO) as well as many other authors have provisionally assigned the drug as BCS class I (high solubility-high permeability) or III (high solubility-low permeability), based on different methods. We determined biperiden BCS class by comparing its permeability to 5 pre-defined compounds: atenolol and ranitidine hydrochloride (low permeability group) and metoprolol tartrate, sodium naproxen and theophylline (high permeability group). Since biperiden permeability was higher than those obtained for high permeability drugs, we classified it as a BCS class I compound. On the other hand, as no differences were obtained for permeability values when apical to basolateral and basolateral to apical fluxes were studied, this drug cannot act as a substrate of efflux transporters. As a consequence of our results, we suggest that the widely used antiparkinsonian drug, biperiden, should be candidate for a waiver of in vivo bioequivalence studies. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Preparation of 99mTc-HYNIC-PEG-liposomes for imaging of the focal sites infection

    International Nuclear Information System (INIS)

    Hong, Jun Pyo; Awh, Ok Doo; Kim, Hyun Suk; Lee, Eun Sook; Lee, Tae Sup; Choi, Tae Hyun; Choi, Chang Woon; Lim, Sang Moo

    2002-01-01

    A new linker, hydrazino nicotinamide (HYNIC), was recently introduced for labelling of liposome with 99m Tc. In this study we synthesized HYNIC derivatized PEG (polyethylene glycol)-liposomes radiolabeled with 99m Tc. In order to synthesize HYNIC-DSPE (distearoyl phosphatidyl ethanolamine) which is a crucial component for 99m Tc chelation, first of all succinimidyl 6-BOC-hydrazinopyridine-3-carboxylic acid was synthesized from 6-chloronicotinic acid by three sequential reactions. A DSPE derivative of succinimidyl 6-BOC-hydrazinopyridine-3-carboxylic acid was transformed into HYNIC-DSPE by HCI/dioxane. HYNIC-PEG-liposomes were prepared by hydration of the dried lipid mixture of EPC (egg phosphatidyl choline): PEG-DSPE : HYNIC-DSPE: cholesterol (1.85:0.15:0.07:1, molar ratio). The HYNIC-PEG-liposomes were labeled with 99m Tc in the presence of SnCl 2 ·2H 2 O (a reducing agent) and tricine (a colignad). To investigate the level of in vivo transchelation of 99m Tc in the liposomes, the 99m Tc-HYNIC-PEG-liposomes were incubated with a molar excess of DTPA, cysteine or glutathione solutions at 37 .deg. C for 24 hours. 6-BOC-hydrazinopyridine-3-carboxylic acid was synthesized with 77.3% overall yield. The HYNIC concentration in the PEG-coated liposome dispersion was 1.08 mM. In condition of considering the measured liposome size of 106 nm, the phospholipid concentration of 77.5 μmol/ ml and the liposomal particle number of 5.2x10 14 liposomes/ml, it is corresponded to approximate 1,250 nicotinyl hydrazine group per liposome in HYNIC-PEG-liposome. The removal of free 99m Tc was not necessary because the labeling efficiency were above 99%. The radiolabeled liposomes maintained 98%, 96% and 99%, respectively, of radioactivity after incubation with transchelators. The radiolabeled liposomes possessed above 90% of the radioactivity in serum. These results suggest that the HYNIC can be synthesized easily and applied in labelling of PEG-liposomes with 99m Tc

  10. Development and pharmacokinetic of antimony encapsulated in liposomes of phosphatidylserine using radioisotopes in experimental leishmaniasis

    International Nuclear Information System (INIS)

    Borborema, Samanta Etel Treiger

    2010-01-01

    Leishmaniasis are a complex of parasitic diseases caused by intra macrophage protozoa of the genus Leishmania, and is fatal if left untreated. Pentavalent antimonials, though toxic and their mechanism of action being unclear, remain the first-line drugs for treatment. Effective therapy could be achieved by delivering antileishmanial drugs to these sites of infection. Liposomes are phospholipid vesicles that promote improvement in the efficacy and action of drugs in target cell. Liposomes are taken up by the cells of mononuclear phagocytic system (MPS). The purpose of this study was to develop a preparation of meglumine antimonate encapsulated in liposomes of phosphatidylserine and to study its pharmacokinetic in healthy mice to establish its metabolism and distribution. Quantitative analysis of antimony from liposomes demonstrated that Neutron Activation Analysis was the most sensitive technique with almost 100 % of accuracy. All liposome formulations presented a mean diameter size of 150 nm. The determination of IC 50 in infected macrophage showed that liposome formulations were between 10 - 63 fold more effective than the free drug, indicating higher selectivity index. By fluorescence microscopy, an increased uptake of fluorescent-liposomes was seen in infected macrophages during short times of incubation compared with non-infected macrophages. Biodistribution studies showed that meglumine antimonate irradiated encapsulated in liposomes of phosphatidylserine promoted a targeting of antimony for MPS tissues and maintained high doses in organs for a prolonged period. In conclusion, these data suggest that meglumine antimonate encapsulated in liposomes showed higher effectiveness than the non-liposomal drug against Leishmania infection. The development of liposome formulations should be a new alternative for the chemotherapy of infection diseases, especially Leishmaniasis, as they are used to sustain and target pharmaceuticals to the local of infection. (author)

  11. Liposomal drug delivery system from laboratory to clinic

    Directory of Open Access Journals (Sweden)

    Kshirsagar N

    2005-01-01

    Full Text Available The main objective of drug delivery systems is to deliver a drug effectively, specifically to the site of action and to achieve greater efficacy and minimise the toxic effects compared to conventional drugs. Amongst various carrier systems, liposomes have generated a great interest because of their versatility. Liposomes are vesicular concentric bilayered structures, which are biocompatible, biodegradable and nonimmumnogenic. They can control the delivery of drugs by targeting the drug to the site of action or by site avoidance drug delivery or by prolonged circulation of drugs. Amphotericin B (Amp B remains the drug of choice in most systemic mycoses and also as a second line treatment for Kala azar. However, its toxic effects often limit its use. Although the liposome delivery system has been tried for several drugs, only a few have been used in patients due to the slow development of necessary large-scale pharmaceutical procedures. This paper reviews the development of the technique for liposomal Amphotericin B (L-Amp-LRC-1, FungisomeTM drug delivery system in our laboratory in collaboration with the department of Biochemistry, Delhi University in India and proving the safety and efficacy of this preparation in clinical practice. It also attempts to compare the efficacy and benefits of our product for Indian patients with those of similar products and it includes facts from the publications that flowed from our work. As compared to conventional Amp B, Fungisome is infused over a much shorter period requiring a smaller volume and no premedication. It was found to be safe in patients who had developed serious unacceptable toxicity with conventional Amp B. In renal transplant patients, Fungisome did not produce any nephrotoxicity. Fungisome is effective in fungal infections resistant to fluconazole, conventional Amp B and in virgin and resistant cases of visceral leishmaniasis. The cost of any drug is of great significance, especially in India

  12. Liposomal clodronate selectively eliminates microglia from primary astrocyte cultures

    Directory of Open Access Journals (Sweden)

    Kumamaru Hiromi

    2012-05-01

    Full Text Available Abstract Background There is increasing interest in astrocyte biology because astrocytes have been demonstrated to play prominent roles in physiological and pathological conditions of the central nervous system, including neuroinflammation. To understand astrocyte biology, primary astrocyte cultures are most commonly used because of the direct accessibility of astrocytes in this system. However, this advantage can be hindered by microglial contamination. Although several authors have warned regarding microglial contamination in this system, complete microglial elimination has never been achieved. Methods The number and proliferative potential of contaminating microglia in primary astrocyte cultures were quantitatively assessed by immunocytologic and flow cytometric analyses. To examine the utility of clodronate for microglial elimination, primary astrocyte cultures or MG-5 cells were exposed to liposomal or free clodronate, and then immunocytologic, flow cytometric, and gene expression analyses were performed. The gene expression profiles of microglia-eliminated and microglia-contaminated cultures were compared after interleukin-6 (IL-6 stimulation. Results The percentage of contaminating microglia exceeded 15% and continued to increase because of their high proliferative activity in conventional primary astrocyte cultures. These contaminating microglia were selectively eliminated low concentration of liposomal clodronate. Although primary microglia and MG-5 cells were killed by both liposomal and free clodronate, free clodronate significantly affected the viability of astrocytes. In contrast, liposomal clodronate selectively eliminated microglia without affecting the viability, proliferation or activation of astrocytes. The efficacy of liposomal clodronate was much higher than that of previously reported methods used for decreasing microglial contamination. Furthermore, we observed rapid tumor necrosis factor-α and IL-1b gene induction in

  13. Measurement and correlation of solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures

    International Nuclear Information System (INIS)

    Wang, Jinxiu; Xie, Chuang; Yin, Qiuxiang; Tao, Linggang; Lv, Jun; Wang, Yongli; He, Fang; Hao, Hongxun

    2016-01-01

    Highlights: • Solubility of cefmenoxime hydrochloride in pure and binary solvents was determined. • The experimental solubility data were correlated by thermodynamic models. • A model was employed to calculate the melting temperature of cefmenoxime hydrochloride. • Mixing thermodynamic properties of cefmenoxime hydrochloride were calculated. - Abstract: The solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures was measured at temperatures from (283.15 to 313.15) K by using the UV spectroscopic method. The results reveal that the solubility of cefmenoxime hydrochloride increases with increasing temperature in all solvent selected. The solubility of cefmenoxime hydrochloride reaches its maximum value when the mole fraction of isopropanol is 0.2 in the binary solvent mixtures of (isopropanol + water). The modified Apelblat equation and the NRTL model were successfully used to correlate the experimental solubility in pure solvents while the modified Apelblat equation, the CNIBS/R–K model and the Jouyban–Acree model were applied to correlate the solubility in binary solvent mixtures. In addition, the mixing thermodynamic properties of cefmenoxime hydrochloride in different solvents were also calculated based on the NRTL model and experimental solubility data.

  14. Analgesic Effect of Intraperitoneal Bupivacaine Hydrochloride After Laparoscopic Sleeve Gastrectomy: a Randomized Clinical Trial.

    Science.gov (United States)

    Alamdari, Nasser Malekpour; Bakhtiyari, Mahmood; Gholizadeh, Barmak; Shariati, Catrine

    2018-03-01

    The indications for sleeve gastrectomy as a primary procedure for the surgical treatment of morbid obesity have increased worldwide. Pain is the most common complaint for patients on the first day after laparoscopic sleeve gastrectomy. There are various methods for decreasing pain after laparoscopic sleeve gastrectomy such as the use of intraperitoneal bupivacaine hydrochloride. This clinical trial was an attempt to discover the effects of intraperitoneal bupivacaine hydrochloride on alleviating postoperative pain after laparoscopic sleeve gastrectomy. In general, 120 patients meeting the inclusion criteria were enrolled. Patients were randomly allocated into two interventions and control groups using a balanced block randomization technique. One group received intraperitoneal bupivacaine hydrochloride (30 cm 3 ), and the other group served as the control one and did not receive bupivacaine hydrochloride. Diclofenac suppository and paracetamol injection were administered to both groups for postoperative pain management. The mean subjective postoperative pain score was significantly decreased in patients who received intraperitoneal bupivacaine hydrochloride within the first 24 h after the surgery; thus, the instillation of bupivacaine hydrochloride was beneficial in managing postoperative pain. The intraoperative peritoneal irrigation of bupivacaine hydrochloride (30 cm 3 , 0.25%) in sleeve gastrectomy patients was safe and effective in reducing postoperative pain, nausea, and vomiting (IRCT2016120329181N4).

  15. Application of magnetic liposomes for magnetically guided transport of muscle relaxants and anti-cancer photodynamic drugs

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, Anatoly A.; Filippov, Victor I.; Alyautdin, Renat N.; Torshina, N.L.; Kuznetsov, O.A. E-mail: oleg@louisiana.edu

    2001-07-01

    Magnetic liposomes containing submicron-sized ferromagnetic particles were prepared encapsulating the muscle relaxant drugs, diadony or diperony, for local anesthesia. Alternatively, metal phthalocyanines (Photosense or Teraphthal), sensitizers for photodynamic or catalytic cancer therapy were loaded into the magnetic liposomes. Animal trials demonstrated successful magnetically guided transport of the drug-loaded liposomes.

  16. Application of magnetic liposomes for magnetically guided transport of muscle relaxants and anti-cancer photodynamic drugs

    International Nuclear Information System (INIS)

    Kuznetsov, Anatoly A.; Filippov, Victor I.; Alyautdin, Renat N.; Torshina, N.L.; Kuznetsov, O.A.

    2001-01-01

    Magnetic liposomes containing submicron-sized ferromagnetic particles were prepared encapsulating the muscle relaxant drugs, diadony or diperony, for local anesthesia. Alternatively, metal phthalocyanines (Photosense or Teraphthal), sensitizers for photodynamic or catalytic cancer therapy were loaded into the magnetic liposomes. Animal trials demonstrated successful magnetically guided transport of the drug-loaded liposomes

  17. Developmental rates of immatures of three Chrysomya species (Diptera: Calliphoridae) under the effect of methylphenidate hydrochloride, phenobarbital, and methylphenidate hydrochloride associated with phenobarbital.

    Science.gov (United States)

    Rezende, Fábio; Alonso, Marcela A; Souza, Carina M; Thyssen, Patrícia J; Linhares, Arício X

    2014-05-01

    Entomotoxicology is focused on obtaining data on necrophagous entomofauna, for criminal investigations purposes. This study aimed to evaluate the effect of different concentrations of methylphenidate hydrochloride, phenobarbital, and their association on the developmental rate, larval and pupal survivorship, and the interval of emergence of adults of Chrysomya albiceps (Wiedemann), Chrysomya megacephala (Fabricius), and Chrysomya putoria (Wiedemann) (Diptera: Calliphoridae). Considering the therapeutic dose (TD) of methylphenidate hydrochloride (0.29 mg/Kg), the concentrations tested were 10× TD, 50× TD, and 100× TD. For phenobarbital, the concentrations used were 1× TD (=150 mg/Kg), 3.3× TD, and 6.7× TD. For the association of the drugs, the combinations used were 10× TD-methylphenidate hydrochloride plus 1× TD-phenobarbital, 50× TD-methylphenidate hydrochloride plus 3.3× TD-phenobarbital, and 100× TD-methylphenidate hydrochloride plus 6.7× TD-phenobarbital. The control group, without addition of drug, was maintained under the same conditions of temperature (25 ± 1 °C), humidity (70 ± 10%), and photoperiod (12 h). Specimens of each group were weighed every 12 h until pupariation. The developmental rate of the three Chrysomya species immatures was monitored. For C. albiceps the developmental time was delayed in 24 h for methylphenidate hydrochloride group and in 12 h for the phenobarbital and the drugs association groups. The effect was observed only at specific ages for C. megacephala, without altering the developmental time. For C. putoria, the developmental time was delayed in 12 h for methylphenidate hydrochloride group and in 24 h for the phenobarbital and the drugs association groups. The emergence interval was similar among all experimental groups, but larval and pupal viabilities were affected in different ways.

  18. Liposomes containing cationic dimethyl dioctadecyl ammonium bromide: formulation, quality control, and lipofection efficiency.

    Science.gov (United States)

    Dass, Crispin R; Walker, Todd L; Burton, Mark A

    2002-01-01

    This article describes a novel, simple, and relatively inexpensive method to prepare cationic liposomes using an ethanol injection/pressure extrusion method. The study also demonstrated that binding erythrosine dye to cationic liposomes results in a shift of the absorption maximum of the dye from 528 nm to 549 nm at pH 4.25, allowing quantification and visualization of these vesicles. In addition, a relatively simple Ficoll-based gradient centrifugation method for separation of lipoplexes from unbound molecules is presented. Laboratory-formulated dimethyl dioctadecyl ammonium bromide (DDAB) containing liposomes were just as efficient in complexing nucleic acids as commercially available types, and binding increased as the positive to neutral lipid ratio was increased. Transfection efficiency of the DDAB-containing liposomes increased as the ratio of cationic to neutral lipid was increased from 1:1 to 4:1 with either PtdChol or DOPE as the neutral lipid. A concomitant increase in cytotoxicity of CSU-SA1 cancer cells was noted as the ratio of positive to neutral lipid of the liposomes was increased. Nevertheless, our present study showed that the 2:1 liposome is a good choice since it delivers functional plasmids at a comparable rate to commercial liposome formulations, has similar toxicities to the less harmful commercial liposomes, and is at least 1000-fold more economical to prepare inhouse, a major factor to be considered in preclinical and clinical studies with these carriers.

  19. Targeting to cells of fluorescent liposomes covalently coupled with monoclonal antibody or protein A

    Science.gov (United States)

    Leserman, Lee D.; Barbet, Jacques; Kourilsky, François; Weinstein, John N.

    1980-12-01

    Many applications envisioned for liposomes in cell biology and chemotherapy require their direction to specific cellular targets1-3. The ability to use antibody as a means of conferring specificity to liposomes would markedly increase their usefulness. We report here a method for covalently coupling soluble proteins, including monoclonal antibody and Staphylococcus aureus protein A (ref. 4), to small sonicated liposomes, by using the heterobifunctional cross-linking reagent N-hydroxysuccinimidyl 3-(2-pyridyldithio)propionate (SPDP, Pharmacia). Liposomes bearing covalently coupled mouse monoclonal antibody against human β2-microglobulin [antibody B1.1G6 (IgG2a, κ) (B. Malissen et al., in preparation)] bound specifically to human, but not to mouse cells. Liposomes bearing protein A became bound to human cells previously incubated with the B1.1G6 antibody, but not to cells incubated without antibody. The coupling method results in efficient binding of protein to the liposomes without aggregation and without denaturation of the coupled ligand; at least 60% of liposomes bound functional protein. Further, liposomes did not leak encapsulated carboxyfluorescein (CF) as a consequence of the reaction.

  20. Liposome accumulation in irradiated tumors display important tumor and dose dependent differences

    DEFF Research Database (Denmark)

    Hansen, Anders Elias; Fliedner, Frederikke Petrine; Henriksen, Jonas Rosager

    2018-01-01

    Radiation therapy may affect several important parameters in the tumor microenvironment and thereby influence the accumulation of liposomes by the enhanced permeability and retention (EPR)-effect. Here we investigate the effect of single dose radiation therapy on liposome tumor accumulation by PET...

  1. Selective partitioning of cholesterol and a model drug into liposomes of varying size

    DEFF Research Database (Denmark)

    Decker, Christiane; Fahr, Alfred; Kuntsche, Judith

    2012-01-01

    The resistance of a lipid bilayer with respect to a bending deformation generally depends on the presence of membrane additives such as sterols, cosurfactants, peptides, and drugs. As a consequence, the partitioning of membrane additives into liposomes becomes selective with respect to liposome s...

  2. Body distributioin of RGD-mediated liposome in brain-targeting drug delivery.

    Science.gov (United States)

    Qin, Jing; Chen, DaWei; Hu, Haiyang; Qiao, MingXi; Zhao, XiuLi; Chen, Baoyu

    2007-09-01

    RGD conjugation liposomes (RGD-liposomes) were evaluated for brain-targeting drug delivery. The flow cytometric in vitro study demonstrated that RGD-liposomes could bind to monocytes and neutrophils effectively. Ferulic acid (4-hydroxy-3-methoxycinnamic, FA) was loaded into liposomes. Rats were subjected to intrastriatal microinjections of 100 units of human recombinant IL-1beta to produce brain inflammation and caudal vein injection of three formulations (FA solution, FA liposome and RGD-coated FA liposome). Animals were sacrificed 15, 30, 60 and 120 min after administration to study the body distribution of the FA in the three formulations. HPLC was used to determine the concentration of FA in vivo with salicylic acid as internal standard. The results of body distribution indicated that RGD-coated liposomes could be mediated into the brain with a 6-fold FA concentration compared to FA solution and 3-fold in comparison to uncoated liposome. Brain targeted delivery was achieved and a reduction in dosage might be allowed.

  3. In vitro and in vivo aspects of N-acyl-phosphatidylethanolamine-containing liposomes

    DEFF Research Database (Denmark)

    Vermehren, C.; Clausen-Beck, B.; Frøkjær, S.

    2003-01-01

    Incorporation of the phospholipid, N-acyl-phosphatidylethanolamine (NAPE), has shown to increase the liposomal stability towards plasma components in vitro. Besides increasing the circulation-time, NAPE has been shown to contain fusiogenic properties. Hence, fusion between NAPE-liposomes and target...

  4. Surface modified liposomes by mannosylated conjugates anchored via the adamantyl moiety in the lipid bilayer.

    Science.gov (United States)

    Stimac, Adela; Segota, Suzana; Dutour Sikirić, Maja; Ribić, Rosana; Frkanec, Leo; Svetličić, Vesna; Tomić, Srđanka; Vranešić, Branka; Frkanec, Ruža

    2012-09-01

    The aim of the present study was to encapsulate mannosylated 1-aminoadamantane and mannosylated adamantyltripeptides, namely [(2R)-N-(adamant-1-yl)-3-(α,β-d-mannopyranosyloxy)-2-methylpropanamide and (2R)-N-[3-(α-d-mannopyranosyloxy)-2-methylpropanoyl]-d,l-(adamant-2-yl)glycyl-l-alanyl-d-isoglutamine] in liposomes. The characterization of liposomes, size and surface morphology was performed using dynamic light scattering (DLS) and atomic force microscopy (AFM). The results have revealed that the encapsulation of examined compounds changes the size and surface of liposomes. After the concanavalin A (ConA) was added to the liposome preparation, increase in liposome size and their aggregation has been observed. The enlargement of liposomes was ascribed to the specific binding of the ConA to the mannose present on the surface of the prepared liposomes. Thus, it has been shown that the adamantyl moiety from mannosylated 1-aminoadamantane and mannosylated adamantyltripeptides can be used as an anchor in the lipid bilayer for carbohydrate moiety exposed on the liposome surface. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Noninvasive control of the transport function of fluorescent coloured liposomal nanoparticles

    Science.gov (United States)

    Stelmashchuk, O.; Zherebtsov, E.; Zherebtsova, A.; Kuznetsova, E.; Vinokurov, A.; Dunaev, A.; Mamoshin, A.; Snimshchikova, I.; Borsukov, A.; Bykov, A.; Meglinski, I.

    2017-06-01

    The use of liposomal nanoparticles with an incorporated active substance is an innovative and promising approach to diagnostics and therapy. The application of liposomal nanoparticle-based drugs allows for targeted localized delivery, overcomes the natural barriers within the body effectively, and minimizes possible side effects. Liposomes are able to contain a variety of ingredients with practically no limitations to their chemical composition, chemical properties, or size of constituent molecules. This study evaluated the ability to control the passage of fluorescent dye-filled liposomes through the intestinal mucosal barrier after oral administration. For this purpose, the increase in transcutaneous registered fluorescence from tetrabromofluorescein dye was recorded and analysed. Fluorescence intensity was measured at the proximal end of the tail of an animal model after oral administration of the liposomes. Measurements were taken at the excitation wavelengths of 365 and 450 nm. The fluorescence intensity in the group treated with the fluorescent contrast agent encapsulated in liposomal particles increased 140% of the initial level, but in the group treated with pure contrast agent, the increase in detected fluorescence intensity did not exceed 110%. Mice that received empty liposomes as well as the control group did not demonstrate statistically significant changes in fluorescence intensity. A potential application of our results is an express laser optical method of monitoring the transport of orally administered liposomal particles. The results can be used to help create new optical tools for use in the development of new drugs and in high-throughput screening used during their testing.

  6. Fast and efficient detection of tuberculosis antigens using liposome encapsulated secretory proteins of Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Dileep Tiwari

    2017-04-01

    Conclusion: Our study demonstrated that the newly developed liposome tuberculosis antigen card test detected antigens in our study population with approximately 97.48% sensitivity and 95.79% specificity. This is the first study to report the liposomal encapsulation of culture filtrate proteins from M. tuberculosis for diagnostic application.

  7. [Separate factors influencing the interaction of carbohydrate- containing liposomes with galactose-specific lectins].

    Science.gov (United States)

    Dvorkin, V M; Vidershaĭn, G Ia

    1984-11-01

    Some natural (Gal-Cer, Lac-Cer, desyalylated gangliosides) and synthetic (HMGal) glycolipids differing in the length of the bridge linking the terminal galactose with the hydrophobic moiety were incorporated into the liposome membranes. The precipitation of the thus obtained vesicles induced by galactose-specific lectin RCA was studied. It was shown that when the amount of the glycolipids used for the incorporation into the liposomes (1 mol. %) was the same, the vesicles with HMGal or Gal-Cer incorporated into them did not precipitate in the presence of lectin, whereas the liposomes with incorporated Lac-Cer or desyalylated gangliosides did precipitate. It was thus concluded that in order for galactose-containing liposomes precipitation by lectin RCA1 to be induced, galactose should be separated from the liposome membrane with a distance not less than 7 A. The nature of lectin-induced nonspecific precipitation of ganglioside-containing liposomes, ganglioside mycelles and cardiolipin-lecithine liposomes containing lactosylceramide was investigated. Some nonspecific ionic interactions of negatively charged liposomes and ganglioside mycelles with lectin were observed, which disappeared with a rise in the NaCl concentration up to 150-200 mM.

  8. Transferrin-modified liposome promotes α-mangostin to penetrate the blood-brain barrier.

    Science.gov (United States)

    Chen, Zhi-Lan; Huang, Man; Wang, Xia-Rong; Fu, Jun; Han, Min; Shen, You-Qing; Xia, Zheng; Gao, Jian-Qing

    2016-02-01

    α-Mangostin (α-M) is a polyphenolic xanthone that protects and improves the survival of cerebral cortical neurons against Aβ oligomer-induced toxicity in rats. α-M is a potential candidate as a treatment for Alzheimer's disease (AD). However, the efficacy was limited by the poor penetration of the drug through the blood-brain barrier (BBB). In this study, we modified the α-M liposome with transferrin (Tf) and investigated the intracellular distribution of liposomes in bEnd3 cells. In addition, the transport of α-M across the BBB in the Tf(α-M) liposome group was examined. In vitro studies demonstrated that the Tf(α-M) liposome could cross the BBB in the form of an integrated liposome. Results of the in vivo studies on the α-M distribution in the brain demonstrated that the Tf(α-M) liposome improved the brain delivery of α-M. These results indicated that the Tf liposome is a potential carrier of α-M against AD. The use of α-Mangostin (α-M) as a potential agent to treat Alzheimer's disease (AD) has been reported. However, its use is limited by the poor penetration through the blood brain barrier. The delivery of this agent by transferrin-modified liposomes was investigated by the authors in this study. The positive results could point to a better drug delivery system for brain targeting. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Distribution of technetium-99m PEG-liposomes during oligofructose-induced laminitis development in horses

    NARCIS (Netherlands)

    Underwood, Claire; Pollitt, Christopher C.; Metselaar, Josbert Maarten; Laverman, Peter; van Bloois, Louis; van den Hoven, Jolanda M.; Storm, Gerrit; van Eps, Andrew W.

    2015-01-01

    Liposomes are phospholipid nanoparticles used for targeted drug delivery. This study aimed to determine whether intravenous liposomes accumulate in lamellar tissue during laminitis development in horses so as to assess their potential for targeted lamellar drug delivery. Polyethylene-glycol (PEG)

  10. [Enhancing effect of Ulex europaeus agglutinin I modified liposomes on oral insulin absorption in mice].

    Science.gov (United States)

    Zhang, Na; Ping, Qi-neng; Xu, Wen-fang

    2004-12-01

    To investigate the enhancing effect on insulin absorption through GI. tract in mice by using the Ulex europaeus agglutinin I (UEA1) modified liposomes as the carrier. UEA1 modified phosphatidylethanolamine (PE) was prepared by conjugating method of 1-ethyl-3-(3'-dimethylaminopropyl) carbodiimide (EDC), then the modified compound (PE-UEA1) was incorporated into the conventional liposomes of insulin to obtain UEA1 modified liposomes. The agglutination test was performed to examine the UEA1 biological activities after synthesis and modification. When liposomes were applied to healthy mice or diabetic mice at insulin dose of 350 u x kg(-1) orally, the hypoglycemic effect was investigated according to the blood glucose level determination. The blood glucose levels of the healthy mice reduced by UEA1 modified liposomes were (84 +/- 15)% at 4 h, (78 +/- 11)% at 8 h and (90 +/- 12)% at 12 h after oral administration. The conventional liposomes and saline showed no effect. The blood glucose levels of the diabetic mice reduced by UEA1 modified liposomes were (73 +/- 7)% at 4 h, (74 +/- 9)% at 8 h, (86 +/- 9)% at 12 h after oral administration. The UEA1 modified liposomes promote the oral absorption of insulin due to the specific-site combination on M cell membrane.

  11. Process optimization by use of design of experiments: Application for liposomalization of FK506.

    Science.gov (United States)

    Toyota, Hiroyasu; Asai, Tomohiro; Oku, Naoto

    2017-05-01

    Design of experiments (DoE) can accelerate the optimization of drug formulations, especially complexed formulas such as those of drugs, using delivery systems. Administration of FK506 encapsulated in liposomes (FK506 liposomes) is an effective approach to treat acute stroke in animal studies. To provide FK506 liposomes as a brain protective agent, it is necessary to manufacture these liposomes with good reproducibility. The objective of this study was to confirm the usefulness of DoE for the process-optimization study of FK506 liposomes. The Box-Behnken design was used to evaluate the effect of the process parameters on the properties of FK506 liposomes. The results of multiple regression analysis showed that there was interaction between the hydration temperature and the freeze-thaw cycle on both the particle size and encapsulation efficiency. An increase in the PBS hydration volume resulted in an increase in encapsulation efficiency. Process parameters had no effect on the ζ-potential. The multiple regression equation showed good predictability of the particle size and the encapsulation efficiency. These results indicated that manufacturing conditions must be taken into consideration to prepare liposomes with desirable properties. DoE would thus be promising approach to optimize the conditions for the manufacturing of liposomes. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Interliposomal transfer of crystal violet dye from DPPC liposomes to magnetoliposomes

    International Nuclear Information System (INIS)

    Koneracka, Martina; Kopcansky, Peter; Sosa, Pavol; Bagelova, Jaroslava; Timko, Milan

    2005-01-01

    Magnetoliposomes offer new challenges in the field of modern biotechnology and biomedicine. To investigate the important mechanism of interliposomal transfer of encapsulated substances, we investigated in the present work magnetoliposomes and liposomes containing the dye crystal violet. Our study of transmembrane transport showed that the dye transfer from DPPC liposomes to magnetoliposomes was temperature dependent

  13. Preparation, characterization and in vitro antimicrobial activity of liposomal ceftazidime and cefepime against Pseudomonas aeruginosa strains

    Science.gov (United States)

    Torres, Ieda Maria Sapateiro; Bento, Etiene Barbosa; Almeida, Larissa da Cunha; de Sá, Luisa Zaiden Carvalho Martins; Lima, Eliana Martins

    2012-01-01

    Pseudomonas aeruginosa is an opportunistic microorganism with the ability to respond to a wide variety of environmental changes, exhibiting a high intrinsic resistance to a number of antimicrobial agents. This low susceptibility to antimicrobial substances is primarily due to the low permeability of its outer membrane, efflux mechanisms and the synthesis of enzymes that promote the degradation of these drugs. Cephalosporins, particularty ceftazidime and cefepime are effective against P. aeruginosa, however, its increasing resistance has limited the usage of these antibiotics. Encapsulating antimicrobial drugs into unilamellar liposomes is an approach that has been investigated in order to overcome microorganism resistance. In this study, antimicrobial activity of liposomal ceftazidime and cefepime against P. aeruginosa ATCC 27853 and P. aeruginosa SPM-1 was compared to that of the free drugs. Liposomal characterization included diameter, encapsulation efficiency and stability. Minimum Inhibitory Concentration (MIC) was determined for free and liposomal forms of both drugs. Minimum Bactericidal Concentration (MBC) was determined at concentrations 1, 2 and 4 times MIC. Average diameter of liposomes was 131.88 nm and encapsulation efficiency for cefepime and ceftazidime were 2.29% end 5.77%, respectively. Improved stability was obtained when liposome formulations were prepared with a 50% molar ratio for cholesterol in relation to the phospholipid. MIC for liposomal antibiotics for both drugs were 50% lower than that of the free drug, demonstrating that liposomal drug delivery systems may contribute to increase the antibacterial activity of these drugs. PMID:24031917

  14. Highly penetrative liposome nanomedicine generated by a biomimetic strategy for enhanced cancer chemotherapy.

    Science.gov (United States)

    Jia, Yali; Sheng, Zonghai; Hu, Dehong; Yan, Fei; Zhu, Mingting; Gao, Guanhui; Wang, Pan; Liu, Xin; Wang, Xiaobing; Zheng, Hairong

    2018-04-25

    Liposome nanomedicine has been successfully applied for cancer chemotherapy in patients. However, in general, the therapeutic efficacy is confined by its limited accumulation and penetration in solid tumors. Here, we established a biomimetic strategy for the preparation of highly penetrative liposome nanomedicine for enhanced chemotherapeutic efficacy. By applying this unique type of nanomedicine, membrane proteins on the cancer cells are used as highly penetrative targeting ligands. Biomimetic liposomes are highly stable, exhibiting a superior in vitro homologous targeting ability, and a 2.25-fold deeper penetration in 3D tumor spheroids when compared to conventional liposome nanomedicine. The fluorescence/photoacoustic dual-modal imaging approach demonstrated enhanced tumor accumulation and improved tumor penetration of the biomimetic liposome in C6 glioma tumor-bearing nude mice. Following the intravenous administration of biomimetic liposome nanomedicine, the tumor inhibition rate reached up to 93.3%, which was significantly higher when compared to that of conventional liposome nanomedicine (69.3%). Moreover, histopathological analyses demonstrated that biomimetic liposome nanomedicine has limited side effects. Therefore, these results suggested that a cancer cell membrane-based biomimetic strategy may provide a breakthrough approach for enhancing drug penetration and improving treatment efficacy, holding a great promise for further clinical studies.

  15. Targeting doxorubicin encapsulated in stealth liposomes to solid tumors by non thermal diode laser.

    Science.gov (United States)

    Ghannam, Magdy M; El Gebaly, Reem; Fadel, Maha

    2016-04-05

    The use of liposomes as drug delivery systems is the most promising technique for targeting drug especially for anticancer therapy. In this study sterically stabilized liposomes was prepared from DPPC/Cholesterol/PEG-PE encapsulated doxorubicin. The effect of lyophilization on liposomal stability and hence expiration date were studied. Moreover, the effect of diode laser on the drug released from liposomesin vitro and in vivo in mice carrying implanted solid tumor were also studied. The results indicated that lyophilization of the prepared liposomes encapsulating doxorubicin led to marked stability when stored at 5 °C and it is possible to use the re-hydrated lyophilized liposomes within 12 days post reconstitution. Moreover, the use of low energy diode laser for targeting anticancer drug to the tumor cells is a promising method in cancer therapy. We can conclude that lyophilization of the liposomes encapsulating doxorubicin lead to marked stability for the liposomes when stored at 5 °C. Moreover, the use of low energy diode laser for targeting anticancer drug to the tumor cells through the use of photosensitive sterically stabilized liposomes loaded with doxorubicin is a promising method. It proved to be applicable and successful for treatment of Ehrlich solid tumors implanted in mice and eliminated toxic side effects of doxorubicin.

  16. Cross-linkable liposomes stabilize a magnetic resonance contrast-enhancing polymeric fastener.

    Science.gov (United States)

    Smith, Cartney E; Kong, Hyunjoon

    2014-04-08

    Liposomes are commonly used to deliver drugs and contrast agents to their target site in a controlled manner. One of the greatest obstacles in the performance of such delivery vehicles is their stability in the presence of serum. Here, we demonstrate a method to stabilize a class of liposomes that load gadolinium, a magnetic resonance (MR) contrast agent, as a model cargo on their surfaces. We hypothesized that the sequential adsorption of a gadolinium-binding chitosan fastener on the liposome surface followed by covalent cross-linking of the lipid bilayer would provide enhanced stability and improved MR signal in the presence of human serum. To investigate this hypothesis, liposomes composed of diyne-containing lipids were assembled and functionalized via chitosan conjugated with a hydrophobic anchor and diethylenetriaminepentaacetic acid (DTPA). This postadsorption cross-linking strategy served to stabilize the thermodynamically favorable association between liposome and polymeric fastener. Furthermore, the chitosan-coated, cross-linked liposomes proved more effective as delivery vehicles of gadolinium than uncross-linked liposomes due to the reduced liposome degradation and chitosan desorption. Overall, this study demonstrates a useful method to stabilize a broad class of particles used for systemic delivery of various molecular payloads.

  17. Effect of Gamma irradiation on the antimicrobial activity of selenomorphiline hydrochloride

    International Nuclear Information System (INIS)

    Bashand, A.S.

    2002-01-01

    The effect of selenomorphiline hydrochloride on dell growth of two steains of bacteria bacillus subtilis as a gram positive and esherichia coli as a gram negative strain and asperagillus flavus as a fungal strain were investigated in batch broth culture supplemented with different concentrations (50, 100, 150, 200, 300 and 400 mg/ml) of irradiated se (1,2,4 KGY) and its control (non irradiated). The data showed that the antibacterial activity of selenomorphiline hydrochloride is concentration and time depenent. The doses 2 doses 2 and 3 KGY of Gamma-radiation were actually the most effective doses activating selenomorphiline hydrochloride as antibiotic

  18. Quantization of buspirone hydrochloride in pure and pharmaceutical formulation by spectrophotometric method

    International Nuclear Information System (INIS)

    Kazi, A.A.; Mumtaz, A.; Sabri, M.U.

    2008-01-01

    A simple and sensitive method is described for the determination of bus pirone hydrochloride in bulk drug and in formulations employing spectrophotometric technique. The method is based on the interaction orbuspirone hydrochloride with ammonium molybdate in acidic media and the absorbance is measured at 700 nm. Beer's Law is obeyed in the range of 5 macro g to 350 micro g/ml and RSD is 0.96% for buspirone hydrochloride. Analytical data for the determination of pure compound is presented along with the application of the proposed method for the analysis of pharmaceutical formulation. (author)

  19. UV Spectrophotometric Method for theEstimation of Itopride Hydrochloride in Pharmaceutical Formulation

    OpenAIRE

    K. R. Gupta; R. R. Joshi; R. B. Chawla; S. G. Wadodkar

    2010-01-01

    Three simple, precise and economical UV methods have been developed for the estimation of itopride hydrochloride in pharmaceutical formulations. Itopride hydrochloride in distilled water shows the maximum absorbance at 258.0 nm (Method A) and in first order derivative spectra of the same shows sharp peak at 247.0 nm, when n = 1 (Method B). Method C utilises area under curve (AUC) in the wavelength range from 262.0-254.0 nm for analysis of itopride hydrochloride. The drug was found to obey Bee...

  20. Systems of pyridine, piperidine, piperazine, morpholine hydrochlorides-terbium (dysprosium) chloride-water

    International Nuclear Information System (INIS)

    Gajfutdinova, R.K.; Sharafutdinova, A.A.; Murinov, Yu.I.

    1988-01-01

    The isothermal cross section method at 25 and 50 deg C is applied to study pyridine hydrochloride-terbium chloride-water (1) piperidine hydrochloride-dysprosium chloride-water (2), piperazine dihydrochloride-dysprosium chloride-water (3) and morpholine hydrochloride-terbium chloride (4) systems. Solubility isotherma prove the formation of incongruently soluble compound of the TbCl 3 x6C 5 H 5 NxHCl composition systems (1). The individuality of the new solid phase is proved by the chemical and DTA methods. Systems (2-4) are of a simple eutonic type

  1. Fast and Convenient NIR Spectroscopy Procedure for Determination of Metformin Hydrochloride in Tablets

    Science.gov (United States)

    Pyzowski, J.; Lenartowicz, M.; Sobańska, A. W.; Brzezińska, E.

    2017-09-01

    A rapid and convenient near-infrared (NIR) reflectance spectroscopic procedure for the determination of metformin hydrochloride in tablets is presented. Determination was based on calibration curves that were obtained using a range of standards containing different concentrations of metformin hydrochloride blended with polyvinylpyrrolidone. The raw spectra of the standards, neat PVP, metformin hydrochloride, and powdered tablets were processed using a Multiplicative Scatter Correction filter as well as by the derivative spectroscopy method to give a basis for the calibration curve construction. The results were validated by thin-layer chromatography followed by UV-densitometry.

  2. Thermoresponsive pegylated bubble liposome nanovectors for efficient siRNA delivery via endosomal escape

    KAUST Repository

    Alamoudi, Kholod; Martins, Patricia; Croissant, Jonas G.; Patil, Sachin; Omar, Haneen; Khashab, Niveen M.

    2017-01-01

    Improving the delivery of siRNA into cancer cells via bubble liposomes. Designing a thermoresponsive pegylated liposome through the introduction of ammonium bicarbonate salt into liposomes so as to control their endosomal escape for gene therapy.A sub-200 nm nanovector was fully characterized and examined for cellular uptake, cytotoxicity, endosomal escape and gene silencing.The siRNA-liposomes were internalized into cancer cells within 5 min and then released siRNAs in the cytosol prior to lysosomal degradation upon external temperature elevation. This was confirmed by confocal bioimaging and gene silencing reaching up to 90% and further demonstrated by the protein inhibition of both target genes.The thermoresponsiveness of ammonium bicarbonate containing liposomes enabled the rapid endosomal escape of the particles and resulted in an efficient gene silencing.

  3. Thermoresponsive pegylated bubble liposome nanovectors for efficient siRNA delivery via endosomal escape

    KAUST Repository

    Alamoudi, Kholod

    2017-05-19

    Improving the delivery of siRNA into cancer cells via bubble liposomes. Designing a thermoresponsive pegylated liposome through the introduction of ammonium bicarbonate salt into liposomes so as to control their endosomal escape for gene therapy.A sub-200 nm nanovector was fully characterized and examined for cellular uptake, cytotoxicity, endosomal escape and gene silencing.The siRNA-liposomes were internalized into cancer cells within 5 min and then released siRNAs in the cytosol prior to lysosomal degradation upon external temperature elevation. This was confirmed by confocal bioimaging and gene silencing reaching up to 90% and further demonstrated by the protein inhibition of both target genes.The thermoresponsiveness of ammonium bicarbonate containing liposomes enabled the rapid endosomal escape of the particles and resulted in an efficient gene silencing.

  4. Liposomes containing alkylated methotrexate analogues for phospholipase A(2) mediated tumor targeted drug delivery

    DEFF Research Database (Denmark)

    Kaasgaard, Thomas; Andresen, Thomas Lars; Jensen, Simon Skøde

    2009-01-01

    of alkylated compounds in liposomes, it was demonstrated that the MTX-analogue partitioned into the water phase and thereby became available for cell uptake. It was concluded that liposomes containing alkylated MTX-analogues show promise as a drug delivery system, although the MTX-analogue needs to be more......Two lipophilic methotrexate analogues have been synthesized and evaluated for cytotoxicity against KATO III and HT-29 human colon cancer cells. Both analogues contained a C-16-alkyl chain attached to the gamma-carboxylic acid and one of the analogues had an additional benzyl group attached...... cytotoxicity was incorporated into liposomes that were designed to be particularly Susceptible to a liposome degrading enzyme, secretory phospholipase A(2) (sPLA(2)), which is found in high concentrations in tumors of several different cancer types. Liposome incorporation was investigated by differential...

  5. Microspectroscopic Study of Liposome-to-cell Interaction Revealed by Förster Resonance Energy Transfer.

    Science.gov (United States)

    Yefimova, Svetlana L; Kurilchenko, Irina Yu; Tkacheva, Tatyana N; Kavok, Nataliya S; Todor, Igor N; Lukianova, Nataliya Yu; Chekhun, Vasyl F; Malyukin, Yuriy V

    2014-03-01

    We report the Förster resonance energy transfer (FRET)-labeling of liposomal vesicles as an effective approach to study in dynamics the interaction of liposomes with living cells of different types (rat hepatocytes, rat bone marrow, mouse fibroblast-like cells and human breast cancer cells) and cell organelles (hepatocyte nuclei). The in vitro experiments were performed using fluorescent microspectroscopic technique. Two fluorescent dyes (DiO as the energy donor and DiI as an acceptor) were preloaded in lipid bilayers of phosphatidylcholine liposomes that ensures the necessary distance between the dyes for effective FRET. The change in time of the donor and acceptor relative fluorescence intensities was used to visualize and trace the liposome-to-cell interaction. We show that FRET-labeling of liposome vesicles allows one to reveal the differences in efficiency and dynamics of these interactions, which are associated with composition, fluidity, and metabolic activity of cell plasma membranes.

  6. Imaging phospholipid conformational disorder and packing in giant multilamellar liposome by confocal Raman microspectroscopy

    Science.gov (United States)

    Noothalapati, Hemanth; Iwasaki, Keita; Yoshimoto, Chikako; Yoshikiyo, Keisuke; Nishikawa, Tomoe; Ando, Masahiro; Hamaguchi, Hiro-o.; Yamamoto, Tatsuyuki

    2017-12-01

    Liposomes are closed phospholipid bilayer systems that have profound applications in fundamental cell biology, pharmaceutics and medicine. Depending on the composition (pure or mixture of phospholipids, presence of cholesterol) and preparation protocol, intra- and inter-chain molecular interactions vary leading to changes in the quality (order and packing) of liposomes. So far it is not possible to image conformational disorders and packing densities within a liposome in a straightforward manner. In this study, we utilized confocal Raman microspectroscopy to visualize structural disorders and packing efficiency within a giant multilamellar liposome model by focusing mainly on three regions in the vibrational spectrum (Csbnd C stretching, Csbnd H deformation and Csbnd H stretching). We estimated properties such as trans/gauche isomers and lateral packing probability. Interestingly, our Raman imaging studies revealed gel phase rich domains and heterogeneous lateral packing within the giant multilamellar liposome.

  7. Targeted Therapy for Acute Autoimmune Myocarditis with Nano-Sized Liposomal FK506 in Rats.

    Directory of Open Access Journals (Sweden)

    Keiji Okuda

    Full Text Available Immunosuppressive agents are used for the treatment of immune-mediated myocarditis; however, the need to develop a more effective therapeutic approach remains. Nano-sized liposomes may accumulate in and selectively deliver drugs to an inflammatory lesion with enhanced vascular permeability. The aims of this study were to investigate the distribution of liposomal FK506, an immunosuppressive drug encapsulated within liposomes, and the drug's effects on cardiac function in a rat experimental autoimmune myocarditis (EAM model. We prepared polyethylene glycol-modified liposomal FK506 (mean diameter: 109.5 ± 4.4 nm. We induced EAM by immunization with porcine myosin and assessed the tissue distribution of the nano-sized beads and liposomal FK506 in this model. After liposomal or free FK506 was administered on days 14 and 17 after immunization, the cytokine expression in the rat hearts along with the histological findings and hemodynamic parameters were determined on day 21. Ex vivo fluorescent imaging revealed that intravenously administered fluorescent-labeled nano-sized beads had accumulated in myocarditic but not normal hearts on day 14 after immunization and thereafter. Compared to the administration of free FK506, FK506 levels were increased in both the plasma and hearts of EAM rats when liposomal FK506 was administered. The administration of liposomal FK506 markedly suppressed the expression of cytokines, such as interferon-γ and tumor necrosis factor-α, and reduced inflammation and fibrosis in the myocardium on day 21 compared to free FK506. The administration of liposomal FK506 also markedly ameliorated cardiac dysfunction on day 21 compared to free FK506. Nano-sized liposomes may be a promising drug delivery system for targeting myocarditic hearts with cardioprotective agents.

  8. Targeted Therapy for Acute Autoimmune Myocarditis with Nano-Sized Liposomal FK506 in Rats.

    Science.gov (United States)

    Okuda, Keiji; Fu, Hai Ying; Matsuzaki, Takashi; Araki, Ryo; Tsuchida, Shota; Thanikachalam, Punniyakoti V; Fukuta, Tatsuya; Asai, Tomohiro; Yamato, Masaki; Sanada, Shoji; Asanuma, Hiroshi; Asano, Yoshihiro; Asakura, Masanori; Hanawa, Haruo; Hao, Hiroyuki; Oku, Naoto; Takashima, Seiji; Kitakaze, Masafumi; Sakata, Yasushi; Minamino, Tetsuo

    2016-01-01

    Immunosuppressive agents are used for the treatment of immune-mediated myocarditis; however, the need to develop a more effective therapeutic approach remains. Nano-sized liposomes may accumulate in and selectively deliver drugs to an inflammatory lesion with enhanced vascular permeability. The aims of this study were to investigate the distribution of liposomal FK506, an immunosuppressive drug encapsulated within liposomes, and the drug's effects on cardiac function in a rat experimental autoimmune myocarditis (EAM) model. We prepared polyethylene glycol-modified liposomal FK506 (mean diameter: 109.5 ± 4.4 nm). We induced EAM by immunization with porcine myosin and assessed the tissue distribution of the nano-sized beads and liposomal FK506 in this model. After liposomal or free FK506 was administered on days 14 and 17 after immunization, the cytokine expression in the rat hearts along with the histological findings and hemodynamic parameters were determined on day 21. Ex vivo fluorescent imaging revealed that intravenously administered fluorescent-labeled nano-sized beads had accumulated in myocarditic but not normal hearts on day 14 after immunization and thereafter. Compared to the administration of free FK506, FK506 levels were increased in both the plasma and hearts of EAM rats when liposomal FK506 was administered. The administration of liposomal FK506 markedly suppressed the expression of cytokines, such as interferon-γ and tumor necrosis factor-α, and reduced inflammation and fibrosis in the myocardium on day 21 compared to free FK506. The administration of liposomal FK506 also markedly ameliorated cardiac dysfunction on day 21 compared to free FK506. Nano-sized liposomes may be a promising drug delivery system for targeting myocarditic hearts with cardioprotective agents.

  9. Prolonged hypoglycemic effect in diabetic dogs due to subcutaneous administration of insulin in liposomes

    International Nuclear Information System (INIS)

    Stevenson, R.W.; Patel, H.M.; Parsons, J.A.; Ryman, B.E.

    1982-01-01

    The biologic action of insulin entrapped in liposomes (phospholipid vesicles) has been investigated following subcutaneous injection to dogs made diabetic with a combination of alloxan and streptozotocin. The fate of the liposomally entrapped material was determined by injecting rats subcutaneously with either 125 I-insulin or the labeled polysaccharide 14 C-inulin, incorporated in liposomes labeled with 3 H-cholesterol. Injection of liposome insulin (0.75 U/kg) to five diabetic dogs resulted in a mean (+/- SEM) blood glucose fall from 16.4 +/- 0.8 to 2.9 +/- 0.4 mmol/L. The glucose level had still not returned to baseline after 24 h and, correspondingly, immunoreactive insulin (IRI) could still be detected in frozen and thawed plasma 24 h after injection. In contrast, the hypoglycemic effect of the same dose of free insulin with or without empty liposomes virtually ended within 8 h and IRI levels returned to baseline by 3 h after injection. In experiments on rats with liposomally entrapped 125 I-insulin or 14 C-inulin the proportion of the injected dose of tracer recoverable by excision of the injection site remained constant after about 1 h and 70% of the dose was still fixed in subcutaneous tissue for at least 5 h thereafter. When the plasma collected 3 h after subcutaneous injection of labeled liposomes containing 125 I-insulin was passed through a column of Sepharose 6B, 50-75% of the 125 I-activity was found in the fractions associated with intact liposomes. One possibility for the persistence of the hypoglycemic effect and of measurable IRI following injection of liposome insulin could be the presence of intact liposomes in the circulation for many hours after adsorption had ceased

  10. Evaluation of the physicochemical properties of liposomes as potential carriers of anticancer drugs: spectroscopic study

    International Nuclear Information System (INIS)

    Pentak, Danuta

    2016-01-01

    Vesicle size and composition are a critical parameter for determining the circulation half-life of liposomes. Size influences the degree of drug encapsulation in liposomes. The geometry, size, and properties of liposomes in an aqueous environment have to be described to enable potential applications of liposome systems as drug carriers. The characteristics of multiple thermotropic phase transitions are also an important consideration in liposomes used for analytical and bioanalytical purposes. The aim of this study was to evaluate the physicochemical properties of liposomes which accommodate hydrophilic and amphiphilic drugs used in cancer therapy. The studied liposomes were prepared with the involvement of the modified reverse-phase evaporation method (mREV). The prepared liposomes had a diameter of 70–150 nm. The analyzed compounds were 1-β-d-arabinofuranosylcytosine, cyclophosphamide, and ifosfamide. In literature, there is no information about simultaneous incorporation of cytarabine, ifosfamide, and cyclophosphamide, in spite of the fact that these drugs have been used for more than 30 years. A combination of the examined drugs is used in CODOX-M/IVAC therapy. CODOX-M/IVAC (cyclophosphamide, doxorubicin, high-dose methotrexate/ifosfamide, etoposide, and high-dose cytarabine) is one of the currently preferred intensive-dose chemotherapy regimens for Burkitt lymphoma (BL). The present research demonstrates the pioneering studies of incorporation of ifosfamide into liposome vesicles, location of and competition between the analyzed drugs and liposome vesicles. The applied methods were nuclear magnetic resonance (NMR), atomic force microscopy (AFM), differential scanning calorimetry (DSC).Graphical Abstract.

  11. Evaluation of the physicochemical properties of liposomes as potential carriers of anticancer drugs: spectroscopic study

    Energy Technology Data Exchange (ETDEWEB)

    Pentak, Danuta, E-mail: danuta.pentak@us.edu.pl [University of Silesia, Department of Materials Chemistry and Chemical Technology, Institute of Chemistry (Poland)

    2016-05-15

    Vesicle size and composition are a critical parameter for determining the circulation half-life of liposomes. Size influences the degree of drug encapsulation in liposomes. The geometry, size, and properties of liposomes in an aqueous environment have to be described to enable potential applications of liposome systems as drug carriers. The characteristics of multiple thermotropic phase transitions are also an important consideration in liposomes used for analytical and bioanalytical purposes. The aim of this study was to evaluate the physicochemical properties of liposomes which accommodate hydrophilic and amphiphilic drugs used in cancer therapy. The studied liposomes were prepared with the involvement of the modified reverse-phase evaporation method (mREV). The prepared liposomes had a diameter of 70–150 nm. The analyzed compounds were 1-β-d-arabinofuranosylcytosine, cyclophosphamide, and ifosfamide. In literature, there is no information about simultaneous incorporation of cytarabine, ifosfamide, and cyclophosphamide, in spite of the fact that these drugs have been used for more than 30 years. A combination of the examined drugs is used in CODOX-M/IVAC therapy. CODOX-M/IVAC (cyclophosphamide, doxorubicin, high-dose methotrexate/ifosfamide, etoposide, and high-dose cytarabine) is one of the currently preferred intensive-dose chemotherapy regimens for Burkitt lymphoma (BL). The present research demonstrates the pioneering studies of incorporation of ifosfamide into liposome vesicles, location of and competition between the analyzed drugs and liposome vesicles. The applied methods were nuclear magnetic resonance (NMR), atomic force microscopy (AFM), differential scanning calorimetry (DSC).Graphical Abstract.

  12. Liposomal Encapsulation for Systemic Delivery of Propranolol via Transdermal Iontophoresis Improves Bone Microarchitecture in Ovariectomized Rats.

    Science.gov (United States)

    Teong, Benjamin; Kuo, Shyh Ming; Tsai, Wei-Hsin; Ho, Mei-Ling; Chen, Chung-Hwan; Huang, Han Hsiang

    2017-04-13

    The stimulatory effects of liposomal propranolol (PRP) on proliferation and differentiation of human osteoblastic cells suggested that the prepared liposomes-encapsulated PRP exerts anabolic effects on bone in vivo. Iontophoresis provides merits such as sustained release of drugs and circumvention of first pass metabolism. This study further investigated and evaluated the anti-osteoporotic effects of liposomal PRP in ovariectomized (OVX) rats via iontophoresis. Rats subjected to OVX were administered with pure or liposomal PRP via iontophoresis or subcutaneous injection twice a week for 12 weeks. Changes in the microarchitecture at the proximal tibia and the fourth lumbar spine were assessed between pure or liposomal PRP treated and non-treated groups using micro-computed tomography. Administration of liposomal PRP at low dose (0.05 mg/kg) via iontophoresis over 2-fold elevated ratio between bone volume and total tissue volume (BV/TV) in proximal tibia to 9.0% whereas treatment with liposomal PRP at low and high (0.5 mg/kg) doses via subcutaneous injection resulted in smaller increases in BV/TV. Significant improvement of BV/TV and bone mineral density (BMD) was also found in the fourth lumbar spine when low-dose liposomal PRP was iontophoretically administered. Iontophoretic low-dose liposomal PRP also elevated trabecular numbers in tibia and trabecular thickness in spine. Enhancement of bone microarchitecture volumes has highlighted that liposomal formulation with transdermal iontophoresis is promising for PRP treatment at the lower dose and with longer duration than its clinical therapeutic range and duration to exhibit optimal effects against bone loss in vivo.

  13. Multilayer Films and Capsules of Sodium Carboxymethylcellulose and Polyhexamethylenguanidine Hydrochloride

    Science.gov (United States)

    Guzenko, Nataliia; Gabchak, Oleksandra; Pakhlov, Evgenij

    The complexation of polyhexamethylenguanidine hydrochloride (PHMG) and sodium carboxymethylcellulose (CMC) was investigated for different conditions. Mixing of equiconcentrated aqueous solutions of the polyelectrolytes was found to result in the formation of an insoluble interpolyelectrolyte complex with an overweight of carboxymethylcellulose. A step-by-step formation of stable, irreversibly adsorbed multilayer film of the polymers was demonstrated using the quartz crystal microbalance method. Unusually thick polymer shells with a large number of loops and tails of the polyanion were formed by the method of layer-by-layer self-assembly of PHMG and CMC on spherical CaCO3 particles. Hollow multilayer capsules stable in neutral media were obtained by dissolution of the inorganic matrix in EDTA solution.

  14. Physical and Chemical Characterization of Poly(hexamethylene biguanide Hydrochloride

    Directory of Open Access Journals (Sweden)

    Luiz Henrique C. Mattoso

    2011-06-01

    Full Text Available We present the characterization of commercially available Poly(hexamethylene biguanide hydrochloride (PHMB, a polymer with biocidal activity and several interesting properties that make this material suitable as a building block for supramolecular chemistry and “smart” materials. We studied polymer structure in water solution by dynamic light scattering, surface tension and capacitance spectroscopy. It shows typical surfactant behavior due to amphiphilic structure and low molecular weight. Spectroscopic (UV/Vis, FT-NIR and thermal characterization (differential scanning calorimetry, DSC, and thermogravimetric analysis, TGA were performed to give additional insight into the material structure in solution and solid state. These results can be the foundation for more detailed investigations on usefulness of PHMB in new complex materials and devices.

  15. Single dose pharmacokinetics of fenspiride hydrochloride: phase I clinical trial.

    Science.gov (United States)

    Montes, B; Catalan, M; Roces, A; Jeanniot, J P; Honorato, J M

    1993-01-01

    The absolute bioavailability of fenspiride has been studied in twelve healthy volunteers. It was administered IV and orally in single doses of 80 mg fenspiride hydrochloride according to a randomised crossover pattern. Following IV administration, the plasma clearance of fenspiride was about 184 ml.min-1, and its apparent volume of distribution was moderately large (215 l). When given orally as a tablet, fenspiride exhibited fairly slow ab- sorption; the maximum plasma concentration (206 ng.ml-1) was achieved 6 h after administration. The absolute bioavailability was almost complete (90%). The tablet had slow release characteristics. The elimination half-life obtained from the plasma data was 14 to 16 h independent of the route of administration.

  16. Adsorption of dodecylamine hydrochloride on graphene oxide in water

    Science.gov (United States)

    Chen, Peng; Li, Hongqiang; Song, Shaoxian; Weng, Xiaoqing; He, Dongsheng; Zhao, Yunliang

    Cationic surfactants in water are difficult to be degraded, leading to serious water pollution. In this work, graphene oxide (GO) was used as an adsorbent for removing Dodecylamine Hydrochloride (DACl), a representative cationic surfactant. X-ray diffraction (XRD), FT-IR spectroscopy and atomic force microscope (AFM) were used to characterize the prepared GO. The adsorption of DACl on GO have been investigated through measurements of adsorption capacity, zeta potential, FTIR, and X-ray photoelectron spectroscopy (XPS). The experimental results have shown that the adsorption kinetics could be described as a rate-limiting pseudo second-order process, and the adsorption isotherm agreed well with the Freundlich model. GO was a good adsorbent for DACl removal, compared with coal fly ash and powdered activated carbon. The adsorption process was endothermic, and could be attributed to electrostatic interaction and hydrogen bonding between DACl and GO.

  17. Sinomenine Hydrochloride Protects against Polymicrobial Sepsis via Autophagy

    Directory of Open Access Journals (Sweden)

    Yu Jiang

    2015-01-01

    Full Text Available Sepsis, a systemic inflammatory response to infection, is the major cause of death in intensive care units (ICUs. The mortality rate of sepsis remains high even though the treatment and understanding of sepsis both continue to improve. Sinomenine (SIN is a natural alkaloid extracted from Chinese medicinal plant Sinomenium acutum, and its hydrochloride salt (Sinomenine hydrochloride, SIN-HCl is widely used to treat rheumatoid arthritis (RA. However, its role in sepsis remains unclear. In the present study, we investigated the role of SIN-HCl in sepsis induced by cecal ligation and puncture (CLP in BALB/c mice and the corresponding mechanism. SIN-HCl treatment improved the survival of BALB/c mice that were subjected to CLP and reduced multiple organ dysfunction and the release of systemic inflammatory mediators. Autophagy activities were examined using Western blotting. The results showed that CLP-induced autophagy was elevated, and SIN-HCl treatment further strengthened the autophagy activity. Autophagy blocker 3-methyladenine (3-MA was used to investigate the mechanism of SIN-HCl in vitro. Autophagy activities were determined by examining the autophagosome formation, which was shown as microtubule-associated protein light chain 3 (LC3 puncta with green immunofluorescence. SIN-HCl reduced lipopolysaccharide (LPS-induced inflammatory cytokine release and increased autophagy in peritoneal macrophages (PM. 3-MA significantly decreased autophagosome formation induced by LPS and SIN-HCl. The decrease of inflammatory cytokines caused by SIN-HCl was partially aggravated by 3-MA treatment. Taken together, our results indicated that SIN-HCl could improve survival, reduce organ damage, and attenuate the release of inflammatory cytokines induced by CLP, at least in part through regulating autophagy activities.

  18. Liposome-based Formulation for Intracellular Delivery of Functional Proteins

    Directory of Open Access Journals (Sweden)

    Benoît Chatin

    2015-01-01

    Full Text Available The intracellular delivery of biologically active protein represents an important emerging strategy for both fundamental and therapeutic applications. Here, we optimized in vitro delivery of two functional proteins, the β-galactosidase (β-gal enzyme and the anti-cytokeratin8 (K8 antibody, using liposome-based formulation. The guanidinium-cholesterol cationic lipid bis (guanidinium-tren-cholesterol (BGTC (bis (guanidinium-tren-cholesterol combined to the colipid dioleoyl phosphatidylethanolamine (DOPE (dioleoyl phosphatidylethanolamine was shown to efficiently deliver the β-gal intracellularly without compromising its activity. The lipid/protein molar ratio, protein amount, and culture medium were demonstrated to be key parameters affecting delivery efficiency. The protein itself is an essential factor requiring selection of the appropriate cationic lipid as illustrated by low K8 binding activity of the anti-K8 antibody using guanidinium-based liposome. Optimization of various lipids led to the identification of the aminoglycoside lipid dioleyl succinyl paromomycin (DOSP associated with the imidazole-based helper lipid MM27 as a potent delivery system for K8 antibody, achieving delivery in 67% of HeLa cells. Cryo-transmission electron microscopy showed that the structure of supramolecular assemblies BGTC:DOPE/β-gal and DOSP:MM27/K8 were different depending on liposome types and lipid/protein molar ratio. Finally, we observed that K8 treatment with DOSP:MM27/K8 rescues the cyclic adenosine monophosphate (cAMP-dependent chloride efflux in F508del-CFTR expressing cells, providing a new tool for the study of channelopathies.

  19. Hyaluronan synthase mediates dye translocation across liposomal membranes

    Directory of Open Access Journals (Sweden)

    Medina Andria P

    2012-01-01

    Full Text Available Abstract Background Hyaluronan (HA is made at the plasma membrane and secreted into the extracellular medium or matrix by phospolipid-dependent hyaluronan synthase (HAS, which is active as a monomer. Since the mechanism by which HA is translocated across membranes is still unresolved, we assessed the presence of an intraprotein pore within HAS by adding purified Streptococcus equisimilis HAS (SeHAS to liposomes preloaded with the fluorophore Cascade Blue (CB. Results CB translocation (efflux was not observed with mock-purified material from empty vector control E. coli membranes, but was induced by SeHAS, purified from membranes, in a time- and dose-dependent manner. CB efflux was eliminated or greatly reduced when purified SeHAS was first treated under conditions that inhibit enzyme activity: heating, oxidization or cysteine modification with N-ethylmaleimide. Reduced CB efflux also occurred with SeHAS K48E or K48F mutants, in which alteration of K48 within membrane domain 2 causes decreased activity and HA product size. The above results used liposomes containing bovine cardiolipin (BCL. An earlier study testing many synthetic lipids found that the best activating lipid for SeHAS is tetraoleoyl cardiolipin (TO-CL and that, in contrast, tetramyristoyl cardiolipin (TM-CL is an inactivating lipid (Weigel et al, J. Biol. Chem. 281, 36542, 2006. Consistent with the effects of these CL species on SeHAS activity, CB efflux was more than 2-fold greater in liposomes made with TO-CL compared to TM-CL. Conclusions The results indicate the presence of an intraprotein pore in HAS and support a model in which HA is translocated to the exterior by HAS itself.

  20. Radiation-induced changes in membrane hydrophobicity in liposomes

    International Nuclear Information System (INIS)

    Nakazawa, Tohru; Nagatsuka, Shinichiro; Yukawa, Osami

    1985-01-01

    Effects of γ-radiation on the physical state of membranes were examined with liposomes of lecithin (phosphatidylcholine) from soybean and rat liver microsomes using spin labeling method. There was a slight increase in the membrane fluidity after irradiation. However, a marked decrease in the membrane hydrophobicity by irradiation was observed in the peripheral region in both types of membranes, in parallel with an increase in the lipid peroxidation. These results suggest that irradiation mainly causes a decrease in the membrane hydrophobicity through lipid peroxidation. (author)

  1. Liposomal Formulation of Retinoids Designed for Enzyme Triggered Release

    DEFF Research Database (Denmark)

    Pedersen, Palle Jacob; Adolph, Sidsel Kramshøj; Subramanian, Arun Kumar

    2010-01-01

    The design of retinoid phospholipid prodrugs is described based on molecular dynamics simulations and cytotoxicity studies of synthetic retinoid esters. The prodrugs are degradable by secretory phospholipase A(2) IIA and have potential in liposomal drug delivery targeting tumors. We have synthesi...... displayed IC50 values in the range of 3-19 mu M toward HT-29 and Colo205 colon cancer cells in the presence of phospholipase A(2), while no significant cell death was observed in the absence of the enzyme....

  2. Biowaiver Monographs for Immediate Release Solid Oral Dosage Forms: Proguanil Hydrochloride.

    NARCIS (Netherlands)

    Plöger, Gerlinde F; Abrahamsson, Bertil; Cristofoletti, Rodrigo; Groot, D I R K W; Langguth, Peter; Mehta, Mehul U; Parr, Alan; Polli, James E; Shah, Vinod P; Tajiri, Tomokazu; Dressman, Jennifer B

    2018-01-01

    Literature data relevant to the decision to waive in vivo bioequivalence testing for the approval of generic immediate release solid oral dosage forms of proguanil hydrochloride are reviewed. To clarify the Biopharmaceutics Classification System (BCS) classification, experimental solubility and

  3. Thermal stability study of crystalline and novel spray-dried amorphous nilotinib hydrochloride

    NARCIS (Netherlands)

    Herbrink, Maikel; Vromans, Herman; Schellens, Jan Hm; Beijnen, Jos H; Nuijen, Bastiaan

    2018-01-01

    The thermal characteristics and the thermal degradation of crystalline and amorphous nilotinib hydrochloride (NH) were studied. The spray drying technique was successfully utilized for the amorphization of NH and was evaluated by spectroscopic techniques and differential scanning calorimetry (DSC).

  4. Thiamine hydrochloride: An efficient catalyst for one-pot synthesis of ...

    Indian Academy of Sciences (India)

    thiamine hydrochloride (VB1) as an inexpensive, non-toxic and metal ion free catalyst at ambient temperature. Keywords. ... from practical applications due to environmental and economic ... filtered and purified by column chromatography on.

  5. Chemical coupling of thiolated chitosan to preformed liposomes improves mucoadhesive properties

    Directory of Open Access Journals (Sweden)

    Gradauer K

    2012-05-01

    Full Text Available Kerstin Gradauer,1 Caroline Vonach,1 Gerd Leitinger,2,3 Dagmar Kolb,2,3 Eleonore Fröhlich,3 Eva Roblegg,4 Andreas Bernkop-Schnürch,5 Ruth Prassl1,61Institute of Biophysics and Nanosystems Research, Austrian Academy of Sciences, Graz, Austria; 2Institute of Cell Biology, Histology, and Embryology, Medical University of Graz, Graz, Austria; 3Center for Medical Research, Medical University of Graz, Graz, Austria; 4Institute of Pharmaceutical Sciences/Pharmaceutical Technology, Karl-Franzens University, Graz, Austria; 5Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria; 6Ludwig Boltzmann Institute for Lung Vascular Research, Graz, AustriaAim: To develop mucoadhesive liposomes by anchoring the polymer chitosan-thioglycolic acid (chitosan-TGA to the liposomal surface to target intestinal mucosal membranes.Methods: Liposomes consisting of phosphatidylcholine (POPC and a maleimide-functionalized lipid were incubated with chitosan-TGA, leading to the formation of a thioether bond between free SH-groups of the polymer and maleimide groups of the liposome. Uncoated and newly generated thiomer-coated liposomes were characterized according to their size, zeta potential, and morphology using photon correlation spectroscopy and transmission electron microscopy. The release behavior of calcitonin and the fluorophore/quencher-couple ANTS/DPX (8-aminonaphthalene-1,3,6-trisulfonic acid/p-xylene-bis- pyridinium bromide from coated and uncoated liposomes, was investigated over 24 hours in simulated gastric and intestinal fluids. To test the mucoadhesive properties of thiomer-coated and uncoated liposomes in-vitro, we used freshly excised porcine small intestine.Results: Liposomes showed a concentration-dependent increase in size – from approximately 167 nm for uncoated liposomes to 439 nm for the highest thiomer concentration used in this study. Likewise, their zeta potentials gradually increased from

  6. Spectrophotometric simultaneous determination of Rabeprazole Sodium and Itopride Hydrochloride in capsule dosage form

    Science.gov (United States)

    Sabnis, Shweta S.; Dhavale, Nilesh D.; Jadhav, Vijay. Y.; Gandhi, Santosh V.

    2008-03-01

    A new simple, economical, rapid, precise and accurate method for simultaneous determination of rabeprazole sodium and itopride hydrochloride in capsule dosage form has been developed. The method is based on ratio spectra derivative spectrophotometry. The amplitudes in the first derivative of the corresponding ratio spectra at 231 nm (minima) and 260 nm were selected to determine rabeprazole sodium and itopride hydrochloride, respectively. The method was validated with respect to linearity, precision and accuracy.

  7. Sustained transdermal release of diltiazem hydrochloride through electron beam irradiated different PVA hydrogel membranes

    Energy Technology Data Exchange (ETDEWEB)

    Bhunia, Tridib [Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India); Goswami, Luna [KIIT School of Biotechnology, KIIT University Campus XI, Patia, Bhubaneswar 751024, Orissa (India); Chattopadhyay, Dipankar [Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India); Bandyopadhyay, Abhijit, E-mail: abpoly@caluniv.ac.in [Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India)

    2011-08-15

    Extremely fast release of diltiazem hydrochloride (water soluble, anti anginal drug used to treat chest pain) together with its faster erosion has been the primary problem in conventional oral therapy. It has been addressed in this paper by encapsulating the drug in electron beam irradiated various poly (vinyl alcohol) hydrogel membranes and delivering it through transdermal route. Results show excellent control over the release of diltiazem hydrochloride through these membranes subject to their physico-mechanicals.

  8. Sustained transdermal release of diltiazem hydrochloride through electron beam irradiated different PVA hydrogel membranes

    Science.gov (United States)

    Bhunia, Tridib; Goswami, Luna; Chattopadhyay, Dipankar; Bandyopadhyay, Abhijit

    2011-08-01

    Extremely fast release of diltiazem hydrochloride (water soluble, anti anginal drug used to treat chest pain) together with its faster erosion has been the primary problem in conventional oral therapy. It has been addressed in this paper by encapsulating the drug in electron beam irradiated various poly (vinyl alcohol) hydrogel membranes and delivering it through transdermal route. Results show excellent control over the release of diltiazem hydrochloride through these membranes subject to their physico-mechanicals.

  9. Sustained transdermal release of diltiazem hydrochloride through electron beam irradiated different PVA hydrogel membranes

    International Nuclear Information System (INIS)

    Bhunia, Tridib; Goswami, Luna; Chattopadhyay, Dipankar; Bandyopadhyay, Abhijit

    2011-01-01

    Extremely fast release of diltiazem hydrochloride (water soluble, anti anginal drug used to treat chest pain) together with its faster erosion has been the primary problem in conventional oral therapy. It has been addressed in this paper by encapsulating the drug in electron beam irradiated various poly (vinyl alcohol) hydrogel membranes and delivering it through transdermal route. Results show excellent control over the release of diltiazem hydrochloride through these membranes subject to their physico-mechanicals.

  10. Anti-Inflammatory Effects of Berberine Hydrochloride in an LPS-Induced Murine Model of Mastitis

    Directory of Open Access Journals (Sweden)

    Xichun Wang

    2018-01-01

    Full Text Available Berberine hydrochloride is an isoquinoline type alkaloid extracted from Berberidaceae, Rutaceae, and other plants. Previous reports have shown that berberine hydrochloride has anti-inflammatory properties. However, the underlying molecular mechanisms remain unclear. In this study, a lipopolysaccharide- (LPS- induced murine model of mastitis was established to explore the anti-inflammatory action of berberine hydrochloride. Sixty mice that had been lactating for 5–7 days were randomly divided into six groups, including control, LPS, three berberine hydrochloride treatment groups (5, 10, and 20 mg/kg, and a dexamethasone (DEX (5 mg/kg group. Berberine hydrochloride was administered intraperitoneally 1 h before and 12 h after LPS-induced mastitis, and all mice were sacrificed 24 h after LPS induction. The pathological and histopathological changes of the mammary glands were observed. The concentrations and mRNA expressions of TNF-α, IL-1β, and IL-6 were measured by ELISA and qRT-PCR. The activation of TLR4 and NF-κB signaling pathways was analyzed by Western blot. Results indicated that berberine hydrochloride significantly attenuated neutrophil infiltration and dose-dependently decreased the secretion and mRNA expressions of TNF-α, IL-1β, and IL-6 within a certain range. Furthermore, berberine hydrochloride suppressed LPS-induced TLR4 and NF-κB p65 activation and the phosphorylation of I-κB. Berberine hydrochloride can provide mice robust protection from LPS-induced mastitis, potentially via the TLR4 and NF-κB pathway.

  11. Anti-Inflammatory Effects of Berberine Hydrochloride in an LPS-Induced Murine Model of Mastitis

    Science.gov (United States)

    Feng, Shibin; Ding, Nana; He, Yanting; Li, Cheng; Li, Manman; Ding, Xuedong; Ding, Hongyan; Li, Jinchun

    2018-01-01

    Berberine hydrochloride is an isoquinoline type alkaloid extracted from Berberidaceae, Rutaceae, and other plants. Previous reports have shown that berberine hydrochloride has anti-inflammatory properties. However, the underlying molecular mechanisms remain unclear. In this study, a lipopolysaccharide- (LPS-) induced murine model of mastitis was established to explore the anti-inflammatory action of berberine hydrochloride. Sixty mice that had been lactating for 5–7 days were randomly divided into six groups, including control, LPS, three berberine hydrochloride treatment groups (5, 10, and 20 mg/kg), and a dexamethasone (DEX) (5 mg/kg) group. Berberine hydrochloride was administered intraperitoneally 1 h before and 12 h after LPS-induced mastitis, and all mice were sacrificed 24 h after LPS induction. The pathological and histopathological changes of the mammary glands were observed. The concentrations and mRNA expressions of TNF-α, IL-1β, and IL-6 were measured by ELISA and qRT-PCR. The activation of TLR4 and NF-κB signaling pathways was analyzed by Western blot. Results indicated that berberine hydrochloride significantly attenuated neutrophil infiltration and dose-dependently decreased the secretion and mRNA expressions of TNF-α, IL-1β, and IL-6 within a certain range. Furthermore, berberine hydrochloride suppressed LPS-induced TLR4 and NF-κB p65 activation and the phosphorylation of I-κB. Berberine hydrochloride can provide mice robust protection from LPS-induced mastitis, potentially via the TLR4 and NF-κB pathway.

  12. SPECTROPHOTOMETRIC METHOD FOR SIMULTANEOUS ESTIMATION OF TOLPERISONE HYDROCHLORIDE AND DICLOFENAC SODIUM IN SYNTHETIC MIXTURE

    OpenAIRE

    Patel Satish A; Hariyani Kaushik P

    2012-01-01

    The present manuscript describes simple, sensitive, rapid, accurate, precise and economical spectrophotometric method for the simultaneous determination of Diclofenac sodium and Tolperisone hydrochloride in bulk and synthetic mixture. The method is based on the simultaneous equations for analysis of both the drugs using methanol as solvent. Diclofenac sodium has absorbance maxima at 281 nm and Tolperisone hydrochloride has absorbance maxima at 255 nm in methanol. The linearity was obtained in...

  13. SPECTROPHOTOMETRIC METHOD FOR SIMULTANEOUS ESTIMATION OF EPERISONE HYDROCHLORIDE AND DICLOFENAC SODIUM IN SYNTHETIC MIXTURE

    OpenAIRE

    Patel Paresh U; Patel Sejal K; Patel Umang J

    2012-01-01

    The present manuscript describes simple, sensitive, rapid, accurate, precise and economical spectrophotometric method for the simultaneous determination of diclofenac sodium and Eperisone hydrochloride in bulk and synthetic mixture. The method is based on the simultaneous equations for analysis of both the drugs using methanol as solvent. Diclofenac sodium has absorbance maxima at 281 nm and Eperisone hydrochloride has absorbance maxima at 255 nm in methanol. The linearity was obtained in the...

  14. Formulation, Development and Evaluation of delayed release capsules of Duloxetine Hydrochloride made of different Enteric Polymers

    OpenAIRE

    Pallavi Yerramsetty; J. Vijaya Ratna; Venkata Ramana Reddy; Praveen Kumar

    2012-01-01

    Delayed release systems have acquired a centre stage in the arena of pharmaceutical research and development. The present study involves formulation and evaluation of Duloxetine Hydrochloride delayed release capsules. Duloxetine Hydrochloride is an acid labile drug. It degrades in the acidic environment of the stomach thus leading to therapeutic inefficacy. Therefore it is necessary to bypass the acidic pH of the stomach which can be achieved by formulating delayed release dosage form by usin...

  15. Polymeric matrix membrane sensors for stability-indicating potentiometric determination of oxybutynin hydrochloride and flavoxate hydrochloride urogenital system drugs.

    Science.gov (United States)

    Heba, Mohamed; Ramadan, Nesrin; El-Laithy, Moustafa

    2008-01-01

    Four polyvinyl chloride (PVC) matrix membrane electrodes responsive to 2 drugs affecting the urogenital system--oxybutynin hydrochloride (OX) and flavoxate hydrochloride (FX)--were developed, described, and characterized. A precipitation-based technique with tungstophosphate (TP) and ammonium reineckate (R) anions as electroactive materials in a PVC matrix with an OX cation was used for electrode 1 and 2 fabrication, respectively. Electrode 3 and 4 fabrication was based on use of the precipitation technique of FX cation with tetrakis (4-chlorophenyl) borate and R anions as electroactive materials. Fast and stable Nernstian responses in the range 1 x 10(-2)-1 x 10(-6) M for the 2 drugs over the pH range 5-8 revealed the performance characteristics of these electrodes, which were evaluated according to International Union of Pure and Applied Chemistry recommendations. The method was applied to FX and OX in their pharmaceutical formulations and in human plasma samples. The 4 proposed sensors were found to be specific for the drugs in the presence of up to 60% of their degradation products. Validation of the method according to the quality assurance standards showed suitability of the proposed electrodes for use in the quality control assessment of these drugs. The recoveries for determination of the drugs by the 4 proposed selective electrodes were 99.5 +/- 0.5, 100.0 +/- 0.4, 99.9 +/- 0.4, and 100.1 +/- 0.4% for sensors 1-4, respectively. Statistical comparison between the results obtained by this method and the official method of the drugs was done, and no significant difference found.

  16. Treating Chronic Tension-type Headache Not Responding to Amitriptyline Hydrochloride With Paroxetine Hydrochloride: A Pilot Evaluation

    Science.gov (United States)

    Holroyd, Kenneth A.; Labus, Jennifer S.; O'Donnell, Francis J.; Cordingley, Gary E.

    2007-01-01

    Context In some individuals, chronic tension-type headache fails to respond to tricyclic antidepressant medications that often serve as first-line therapy. Objective To evaluate the clinical efficacy of paroxetine hydrochloride for chronic tension-type headache not responding to amitriptyline hydrochloride. Design and Setting Open-label trial of paroxetine conducted at 2 outpatient sites in Ohio. Participants and Intervention Thirty-one adults (mean age, 37 years; 20 women) with chronic tension-type headache (mean, 25 headache days per month) who had failed to respond (less than 30% improvement) to treatment with either amitriptyline (n = 13) or matched placebo (n = 18). All participants were treated with paroxetine (up to 40 mg per day) in a 9-month protocol. Outcome Measures Monthly headache index calculated as the mean of pain ratings (0 to 10 scale) recorded by participants in a diary 4 times per day, number of days per month with at least moderate pain (pain rating of 5 or greater), and analgesic medication use. Results In patients who had not responded to amitriptyline, paroxetine failed to reduce chronic tension-type headaches or analgesic medication use. In patients who had not responded to placebo, paroxetine produced modest reductions in chronic tension-type headaches and analgesic use. Conclusions We found no evidence that chronic tension-type headaches that failed to respond to tricyclic antidepressant therapy with amitriptyline improved when subsequently treated with paroxetine. More support was found for the efficacy of paroxetine in patients with chronic tension-type headaches who had failed to respond to placebo. PMID:14511278

  17. HPLC method validation for modernization of the tetracycline hydrochloride capsule USP monograph

    Directory of Open Access Journals (Sweden)

    Emad M. Hussien

    2014-12-01

    Full Text Available This paper is a continuation to our previous work aiming at development and validation of a reversed-phase HPLC for modernization of tetracycline-related USP monographs and the USP general chapter . Previous results showed that the method is accurate and precise for the assay of tetracycline hydrochloride and the limit of 4-epianhydrotetracycline impurity in the drug substance and oral suspension monographs. The aim of the current paper is to examine the feasibility of the method for modernization of USP tetracycline hydrochloride capsule monograph. Specificity, linearity, accuracy and precision were examined for tetracycline hydrochloride assay and 4-epianhydrotetracycline limit. The method was linear in the concentration range from 80% to 160% (r>0.9998 of the assay concentration (0.1 mg/mL for tetracycline hydrochloride and from 50% to 150% (r>0.997 of the acceptance criteria specified in tetracycline hydrochloride capsule monograph for 4-epianhydrotetracycline (NMT 3.0%. The recovery at three concentration levels for tetracycline hydrochloride assay was between 99% and 101% and the RSD from six preparations at the concentration 0.1 mg/mL is less than 0.6%. The recovery for 4-epianhydrotetracycline limit procedure over the concentration range from 50% to 150% is between 96% and 102% with RSD less than 5%. The results met the specified acceptance criteria.

  18. Combination atovaquone and proguanil hydrochloride vs. halofantrine for treatment of acute Plasmodium falciparum malaria in children.

    Science.gov (United States)

    Anabwani, G; Canfield, C J; Hutchinson, D B

    1999-05-01

    Malaria is a major cause of pediatric mortality in sub-Saharan Africa. Worldwide estimates of mortality among children with Plasmodium falciparum malaria range from 1 to 2 million deaths per year. Management of malaria is increasingly difficult because of the global spread of drug-resistant strains of P. falciparum. There is an urgent need for safe and effective new therapies to treat multidrug-resistant malaria. This open label, randomized trial compared atovaquone and proguanil hydrochloride with halofantrine for treatment of acute, uncomplicated P. falciparum malaria in children age 3 to 12 years (84 patients per group). Study drug dosages were adjusted by weight (approximately 20 and 8 mg/kg daily for three doses for atovaquone and proguanil hydrochloride and 8 mg/kg every 6 h for three doses for halofantrine). Patients were monitored by serial clinical and laboratory assessments for 28 days after starting treatment. Both regimens were effective (cure rate, 93.8% for atovaquone and proguanil hydrochloride and 90.4% for halofantrine) and produced prompt defervescence. Mean parasite clearance times were 50.2 h for halofantrine and 64.9 h for atovaquone and proguanil hydrochloride. More adverse experiences were reported in children treated with halofantrine (119) than with atovaquone and proguanil hydrochloride (73). In Kenyan children the combination of atovaquone and proguanil hydrochloride has efficacy comparable with that of halofantrine for treatment of acute uncomplicated multidrug-resistant falciparum malaria and is associated with a lower rate of adverse events.

  19. In-silico analysis of amotosalen hydrochloride binding to CD-61 of platelets

    International Nuclear Information System (INIS)

    Chaudhary, H.T.

    2016-01-01

    To determine the docking of Amotosalen hydrochloride (AH) at CD-61 of platelets, and to suggest the cause of bleeding in AH treated platelets transfusion. Study Design: Descriptive study. Place and Duration of Study: Medical College, Taif University, Taif, Saudi Arabia, from October 2014 to May 2015. Methodology: The study was carried out in-silico. PDB (protein data bank) code of Tirofiban bound to CD-61 was 2vdm. CD-61 was docked with Tirofiban using online docking tools, i.e. Patchdock and Firedock. Then, Amotosalen hydrochloride and CD-61 were also docked. Best docking poses to active sites of 2vdm were found. Ligplot of interactions of ligands and CD-61 were obtained. Then comparison of hydrogen bonds, hydrogen bond lengths, and hydrophobic bonds of 2vdm molecule and best poses of docking results were done. Patchdock and Firedock results of best poses were also analysed using SPSS version 16. Results: More amino acids were involved in hydrogen and hydrophobic bonds in Patchdock and Firedock docking of Amotosalen hydrochloride with CD-61 than Patchdock and Firedock docking of CD-61 with Tirofiban. The binding energy was more in latter than former. Conclusion: Amotosalen hydrochloride binds to the active site of CD-61 with weaker binding force. Haemorrhage seen in Amotosalen hydrochloride-treated platelets might be due to binding of Amotosalen hydrochloride to CD-61. (author)

  20. RP-HPLC Estimation of Imipramine Hydrochloride and Diazepam in Tablets.

    Science.gov (United States)

    Srikantha, D; Raju, R R

    2015-01-01

    A simple and rapid reversed phase-high performance liquid chromatographic method was developed for simultaneous determination of imipramine hydrochloride and diazepam in pharmaceutical formulations. The elution was done in isocratic mode utilizing a mobile phase consisting of methanol:water:0.1M sodium acetate (30:50:20 v/v/v) on Chromosil C18 column with a flow rate of 1.0 ml/min and with detection at 243 nm. The measured retention time was 3.33±0.02 min for imipramine hydrochloride and 4.64±0.02 min for diazepam. Linearity was measured in the range 25-150 μg/ml for imipramine hydrochloride (r(2)=0.999) and in the range 5-30 μg/ml for diazepam (r(2)=0.9994), respectively. The limits of detection and quantitation were 0.03 and 0.1 μg/ml for imipramine hydrochloride and 0.02 and 0.07 μg/ml for diazepam. Satisfactory validation was also obtained from recovery (100.95-101.52% for imipramine hydrochloride and 99.47-100.33% for diazepam) studies, intraday and interday precision (hydrochloride and diazepam in tablets.

  1. Influence of polymer size, liposomal composition, surface charge, and temperature on the permeability of pH-sensitive liposomes containing lipid-anchored poly(2-ethylacrylic acid

    Directory of Open Access Journals (Sweden)

    Lu T

    2012-09-01

    Full Text Available Tingli Lu,1 Zhao Wang,2 Yufan Ma,1 Yang Zhang,2 Tao Chen1,21Key Laboratory for Space Bioscience and Biotechnology, School of Life Science, Northwestern Polytechnical University, 2Liposome Research Centre, Xi'an, ChinaBackground: Liposomes containing pH-sensitive polymers are promising candidates for the treatment of tumors and localized infection. This study aimed to identify parameters influencing the extent of contents release from poly(ethylacrylic acid (PEAA vesicles, focusing on the effects of polymer size, lipid composition, vesicle surface charge, and temperature.Methods: Anchored lipid pH-sensitive PEAA was synthesized using PEAA with a molecular weight of 8.4 kDa. PEAA vesicles were prepared by insertion of the lipid-anchored PEAA into preformed large unilamellar vesicles. The preformed liposomes were manipulated by varying the phosphocholine and cholesterol content, and by adding negative or positive charges to the liposomes. A calcein release assay was used to evaluate the effects of polymer size, liposome composition, surface charge, and temperature on liposomal permeability.Results: The release efficiency of the calcein-entrapped vesicles was found to be dependent on the PEAA polymer size. PEAA vesicles containing a phosphatidylcholine to cholesterol ratio of 60:40 (mol/mol released more than 80% of their calcein content when the molecular weight of PEAA was larger than 8.4 kDa. Therefore, the same-sized polymer of 8.4 kDa was used for the rest of study. The calcein release potential was found to decrease as the percentage of cholesterol increased and with an increase in the phosphocholine acyl chain length (DMPC . DPPC . DSPC. Negatively charged and neutral vesicles released similar amounts of calcein, whereas positively charged liposomes released a significant amount of their contents. pH-sensitive release was dependent on temperature. Dramatic content release was observed at higher temperatures.Conclusion: The observed

  2. An enantioselective synthesis of S-[gamma]-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[3-[sup 14]C] hydrochloride, an important metabolite of fluoxetine hydrochloride

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, W.J. (Lilly (Eli) and Co., Indianapolis, IN (United States). Lilly Research Labs.)

    1992-06-01

    The S-enantiomer of [gamma]-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[3-[sup 14]C] hydrochloride has been prepared in eight steps from acetophenone-[carbonyl-[sup 14]C]. The key step in the synthesis involved the enantioselective reduction of R-2-chloroacetophenone-[1-[sup 14]C]with (-)-diisopinocampheyl-chloroborane in an 86.5% yield. The chlorohydrin was converted to R-phenyloxirane-[1-[sup 14]C], which was subsequently converted to the corresponding R-cyanohydrin by reaction with TMS-CN/CaO. Borane reduction and arylation, followed by salt formation yielded S-[gamma]-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[3-[sup 14]C] hydrochloride. (author).

  3. An enantioselective synthesis of S-γ-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[3-14C] hydrochloride, an important metabolite of fluoxetine hydrochloride

    International Nuclear Information System (INIS)

    Wheeler, W.J.

    1992-01-01

    The S-enantiomer of γ-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[3- 14 C] hydrochloride has been prepared in eight steps from acetophenone-[carbonyl- 14 C]. The key step in the synthesis involved the enantioselective reduction of R-2-chloroacetophenone-[1- 14 C]with (-)-diisopinocampheyl-chloroborane in an 86.5% yield. The chlorohydrin was converted to R-phenyloxirane-[1- 14 C], which was subsequently converted to the corresponding R-cyanohydrin by reaction with TMS-CN/CaO. Borane reduction and arylation, followed by salt formation yielded S-γ-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[3- 14 C] hydrochloride. (author)

  4. In Vitro and In Vivo Effective Gene Delivery with Novel Liposomal Bubbles

    Science.gov (United States)

    Nishiie, Norihito; Suzuki, Ryo; Oda, Yusuke; Hirata, Keiichi; Taira, Yuichiro; Utoguchi, Naoki; Negishi, Yoichi; Maruyama, Kazuo

    2010-03-01

    Microbubbles, which were ultrasound contrast agents, could improve the transfection efficiency by cavitation with ultrasound exposure. However, conventional microbubbles had some problems regarding size and targeting ability. To solve these problems, we paid attention to liposomes that had many advantages as drug, antigen and gene delivery carriers. Because they can easily be controlled their size and added a targeting function. And we succeeded to prepare novel liposomal bubbles (Bubble liposomes) entrapping perfluoropropane which was utilized for contrast enhancement in ultrasonography. In this study, we assessed the feasibility of Bubble liposomes as gene delivery tools utilized cavitation by ultrasound exposure. In vitro gene delivery, Bubble liposomes could deliver plasmid DNA to many cell types such as tumor cells, T cell line and endothelial cells without cytotoxicity. In vivo gene delivery, Bubble liposomes could effectively deliver plasmid DNA into mouse femoral artery. This method was more effectively than conventional lipofection. We conclude that Bubble liposomes are unique and efficient gene delivery tools in vitro and in vivo.

  5. Innovative bionanocomposite films of edible proteins containing liposome-encapsulated nisin and halloysite nanoclay.

    Science.gov (United States)

    Boelter, Juliana Ferreira; Brandelli, Adriano

    2016-09-01

    Films and coatings based on natural polymers have gained increased interest for food packaging applications. In this work, halloysite and phosphatidylcholine liposomes encapsulating nisin were used to develop nanocomposite films of gelatin and casein. Liposomes prepared with either soybean lecithin or Phospholipon(®) showed particle size ranging from 124 to 178nm and high entrapment efficiency (94-100%). Considering their stability, Phospholipon(®) liposomes with 1.0mg/ml nisin were selected for incorporation into nanocomposite films containing 0.5g/l halloysite. The films presented antimicrobial activity against Listeria monocytogenes, Clostridium perfringens and Bacillus cereus. Scanning electron microscopy revealed that the films had a smooth surface, but showed increased roughness with addition of liposomes and halloysite. Casein films were thinner and slightly yellowish, less rigid and very elastic as compared with gelatin films. Thermogravimetric analysis showed a decrease of the degradation temperature for casein films added with liposomes. The glass transition temperature decreased with addition of liposomes and halloysite. Gelatin and casein films containing nisin-loaded liposomes and halloysite represent an interesting alternative for development of active food packaging. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Preparation and quality evaluation of LHRHa-targeted Brucea javanica oil liposomes

    Directory of Open Access Journals (Sweden)

    Xiao-juan LIU

    2013-07-01

    Full Text Available Objective To prepare luteinizing hormone-releasing hormone a (LHRHa targeted Bruceajavanicaliposomes and evaluate its quality. Methods The LHRHa-targeted Bruceajavanicaliposome was prepared by thin layer dispersion together with biotin¬streptavidin bridge method. The optimum formation was selected by means of orthogonal design of experiment. The morphology of liposome was observed with transmission electron microscope. Zetasizer Nano ZS analyzer was used to measure the particle size and zeta potential. The entrapment efficiency was determined by ultra-violet spectroscopy and column chromatography. Centrifugal acceleration experiment and determination of leak rate were performed to prove the liposome stability. The targeting ability of liposome was appraised by cell experiment in vitro. Results The formed optimum formula was as follows: the ratio of lecithin to cholesterol was 4:1, Brucea javanicaoil:lipid was 3:10, DSPE-PEG (2000-Biotin:lecithin content was 3%, ultrasonic-homogenized for 8 minutes. Liposomes were round in shape, the average diameter and zeta potential of liposome were 155.1±14.5mm and –(24.1±0.54 mV, respectively. The average entrapment efficiency was 92.2%. Binding capacity with the A2780/DDP cell line in the LHRHa-targeted liposomes was 2.7 times higher than that in the non-targeting liposomes. Conclusion The technique of preparing LHRHa-targeted Bruceajavanicaliposome is suitable, and high in entrapment efficiency, with good stability and targeting ability.

  7. Novel Nano-Liposome Formulation for Dry Eyes with Components Similar to the Preocular Tear Film

    Directory of Open Access Journals (Sweden)

    Marta Vicario-de-la-Torre

    2018-04-01

    Full Text Available Dry eye is commonly treated with artificial tears; however, developing artificial tears similar to natural tears is difficult due to the complex nature of tears. We characterized and evaluated a novel artificial tear formulation with components similar to the lipid and aqueous constituents of natural tears. Nano-liposomes, composed in part of phosphatidylcholine, were dispersed in an aqueous solution of bioadhesive sodium hyaluronate. Liposome size, zeta potential, and physicochemical properties of the fresh and stored (4 °C liposomal formulation were analyzed. In vitro tolerance was tested using human corneal and conjunctival cell lines by exposures of 15 min to 4 h. The tolerance of the liposomal formulation was evaluated in animals (rabbits. The average liposome size was 186.3 ± 7.0 nm, and the zeta potential was negative. The osmolarity of the formulation was 198.6 ± 1.7 mOsm, with a surface tension of 36.5 ± 0.4 mN/m and viscosity of 3.05 ± 0.02 mPa·s. Viability values in the human corneal and conjunctival cell lines were always >80%, even after liposomal formulation storage for 8 weeks. Discomfort and clinical signs after instillation in rabbit eyes were absent. The new formulation, based on phosphatidylcholine-liposomes dispersed in sodium hyaluronate has suitable components and characteristics, including high in vitro cell viability and good in vivo tolerance, to serve as a tear substitute.

  8. Preparation and properties of functional mixed-lipid liposomes by γ-ray irradiation

    International Nuclear Information System (INIS)

    Hosoi, Fumio; Omichi, Hideki; Akama, Kazuhiro; Awai, Kouji; Yano, Yoshihiro; Nakano, Yoshio

    1998-01-01

    The feature of mixed-lipid liposomes such as polymerization and polymerized liposomes stability were investigated to find means for producing red cells containing hemoglobin inside the liposomes. The surface pressure-area isotherm values of the mixed-lipid monolayer indicated 1-stearoyl-2-(2,4-octadecadienoyl)-glycero-3-phosphocholine (SOPC) to be immiscible in cholesterol (Chol) and stearic acid (SA), and each component to contain separate domains in the bilayer membrane of liposomes. Radiation induced polymerization of mixed-SOPC liposomes was carried out using γ-rays from 60 Co at 4degC to stabilize lipid bilayers. The polymer yield increased significantly by adding Chol and SA to SOPC. The rate of polymerization of SOPC liposomes increased linearly with increasing of dose rate. The molecular weight of the polymer decreased with an increase in irradiation time. Irradiated SOPC/Chol/SA liposome vesicle size was affected by freeze-thawing. The vesicle size did not change when SOPC/Chol/SA was present in the system due to the addition of immiscible saturated 1,2-dipalmitoyl-glycero-3-phosphocholine (DPPC). (author)

  9. Near-infrared light-responsive liposomal contrast agent for photoacoustic imaging and drug release applications.

    Science.gov (United States)

    Sivasubramanian, Kathyayini; Mathiyazhakan, Malathi; Wiraja, Christian; Upputuri, Paul Kumar; Xu, Chenjie; Pramanik, Manojit

    2017-04-01

    Photoacoustic imaging has become an emerging tool for theranostic applications. Not only does it help in release and therapeutic applications. We explore near-infrared light-sensitive liposomes coated with gold nanostars (AuNSs) for both imaging and drug release applications using a photoacoustic imaging system. Being amphiphilic, the liposomes lipid bilayer and the aqueous core enable encapsulation of both hydrophobic and hydrophilic drugs. The AuNSs on the surface of the liposomes act as photon absorbers due to their intrinsic surface plasmon resonance. Upon excitation by laser light at specific wavelength, AuNSs facilitate rapid release of the contents encapsulated in the liposomes due to local heating and pressure wave formation (photoacoustic wave). Herein, we describe the design and optimization of the AuNSs-coated liposomes and demonstrate the release of both hydrophobic and hydrophilic model drugs (paclitaxel and calcein, respectively) through laser excitation at near-infrared wavelength. The use of AuNSs-coated liposomes as contrast agents for photoacoustic imaging is also explored with tissue phantom experiments. In comparison to blood, the AuNSs-coated liposomes have better contrast (approximately two times) at 2-cm imaging depth.

  10. Biophysical characterization of V3-lipopeptide liposomes influencing HIV-1 infectivity

    International Nuclear Information System (INIS)

    Rizos, Apostolos K.; Baritaki, Stavroula; Tsikalas, Ioannis; Doetschman, David C.; Spandidos, Demetrios A.; Krambovitis, Elias

    2007-01-01

    The V3-loop of the HIV-1 gp120 alters host cell immune function and modulates infectivity. We investigated biophysical parameters of liposome constructs with embedded lipopeptides from the principle neutralizing domain of the V3-loop and their influence on viral infectivity. Dynamic light scattering measurements showed liposome supramolecular structures with hydrodynamic radius of the order of 900 and 1300 nm for plain and V3-lipopeptide liposomes. Electron paramagnetic resonance measurements showed almost identical local microenvironment. The difference in liposome hydrodynamic radius was attributed to the fluctuating ionic environment of the V3-lipopeptide liposomes. In vitro HIV-1 infectivity assays showed that plain liposomes reduced virus production in all cell cultures, probably due to the hydrophobic nature of the aggregates. Liposomes carrying V3-lipopeptides with different cationic potentials restored and even enhanced infectivity (p < 0.05). These results highlight the need for elucidation of the involvement of lipid bilayers as dynamic components in supramolecular structures and in HIV-1 fusion mechanisms

  11. trans-Double Bond-Containing Liposomes as Potential Carriers for Drug Delivery

    Directory of Open Access Journals (Sweden)

    Giorgia Giacometti

    2017-11-01

    Full Text Available The use of liposomes has been crucial for investigations in biomimetic chemical biology as a membrane model and in medicinal chemistry for drug delivery. Liposomes are made of phospholipids whose biophysical characteristics strongly depend on the type of fatty acid moiety, where natural unsaturated lipids always have the double bond geometry in the cis configuration. The influence of lipid double bond configuration had not been considered so far with respect to the competence of liposomes in delivery. We were interested in evaluating possible changes in the molecular properties induced by the conversion of the double bond from cis to trans geometry. Here we report on the effects of the addition of trans-phospholipids supplied in different amounts to other liposome constituents (cholesterol, neutral phospholipids and cationic surfactants, on the size, ζ-potential and stability of liposomal formulations and on their ability to encapsulate two dyes such as rhodamine B and fluorescein. From a biotechnological point of view, trans-containing liposomes proved to have different characteristics from those containing the cis analogues, and to influence the incorporation and release of the dyes. These results open new perspectives in the use of the unnatural lipid geometry, for the purpose of changing liposome behavior and/or of obtaining molecular interferences, also in view of synergic effects of cell toxicity, especially in antitumoral strategies.

  12. Carrier-inside-carrier: polyelectrolyte microcapsules as reservoir for drug-loaded liposomes.

    Science.gov (United States)

    Maniti, Ofelia; Rebaud, Samuel; Sarkis, Joe; Jia, Yi; Zhao, Jie; Marcillat, Olivier; Granjon, Thierry; Blum, Loïc; Li, Junbai; Girard-Egrot, Agnès

    2015-01-01

    Conventional liposomes have a short life-time in blood, unless they are protected by a polymer envelope, most often polyethylene glycol. However, these stabilizing polymers frequently interfere with cellular uptake, impede liposome-membrane fusion and inhibit escape of liposome content from endosomes. To overcome such drawbacks, polymer-based systems as carriers for liposomes are currently developed. Conforming to this approach, we propose a new and convenient method for embedding small size liposomes, 30-100 nm, inside porous calcium carbonate microparticles. These microparticles served as templates for deposition of various polyelectrolytes to form a protective shell. The carbonate particles were then dissolved to yield hollow polyelectrolyte microcapsules. The main advantage of using this method for liposome encapsulation is that carbonate particles can serve as a sacrificial template for deposition of virtually any polyelectrolyte. By carefully choosing the shell composition, bioavailability of the liposomes and of the encapsulated drug can be modulated to respond to biological requirements and to improve drug delivery to the cytoplasm and avoid endosomal escape.

  13. Magnetic liposomes based on nickel ferrite nanoparticles for biomedical applications.

    Science.gov (United States)

    Rodrigues, Ana Rita O; Gomes, I T; Almeida, Bernardo G; Araújo, J P; Castanheira, Elisabete M S; Coutinho, Paulo J G

    2015-07-21

    Nickel ferrite nanoparticles with superparamagnetic behavior at room temperature were synthesized using a coprecipitation method. These magnetic nanoparticles were either covered with a lipid bilayer, forming dry magnetic liposomes (DMLs), or entrapped in liposomes, originating aqueous magnetoliposomes (AMLs). A new and promising method for the synthesis of DMLs is described. The presence of the lipid bilayer in DMLs was confirmed by FRET (Förster Resonance Energy Transfer) measurements between the fluorescent-labeled lipids NBD-C12-HPC (NBD acting as a donor) included in the second lipid layer and rhodamine B-DOPE (acceptor) in the first lipid layer. An average donor-acceptor distance of 3 nm was estimated. Assays of the non-specific interactions of magnetoliposomes with biological membranes (modeled using giant unilamellar vesicles, GUVs) were performed. Membrane fusion between both aqueous and dry magnetoliposomes and GUVs was confirmed by FRET, which is an important result regarding applications of these systems both as hyperthermia agents and antitumor drug nanocarriers.

  14. Elastic liposomes as novel carriers: recent advances in drug delivery

    Directory of Open Access Journals (Sweden)

    Hussain A

    2017-07-01

    Full Text Available Afzal Hussain,1,2 Sima Singh,1 Dinesh Sharma,3 Thomas J Webster,4 Kausar Shafaat,2 Abdul Faruk5 1Department of Pharmaceutical Sciences and Technology, Birla Institute of Technology, Mesra, Ranchi, Jharkhand, India; 2Faculty of Pharmacy, Sachchidananda Sinha College, Aurangabad, Bihar, India; 3Zifam Pyrex Myanmar Co. Ltd., Yangon, Myanmar; 4Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 5Department of Pharmaceutical Sciences, Hemwati Nandan Bahuguna Garhwal University, Srinagar, Uttarakhand, India Abstract: Elastic liposomes (EL are some of the most versatile deformable vesicular carriers that comprise physiologically biocompatible lipids and surfactants for the delivery of numerous challenging molecules and have marked advantages over other colloidal systems. They have been investigated for a wide range of applications in pharmaceutical technology through topical, transdermal, nasal, and oral routes for efficient and effective drug delivery. Increased drug encapsulation efficiency, enhanced drug permeation and penetration into or across the skin, and ultradeformability have led to widespread interest in ELs to modulate drug release, permeation, and drug action more efficiently than conventional drug-release vehicles. This review provides insights into the versatile role that ELs play in the delivery of numerous drugs and biomolecules by improving drug release, permeation, and penetration across the skin as well as stability. Furthermore, it provides future directions that should ensure the widespread use of ELs across all medical fields. Keywords: elastic liposomes, drug delivery, topical, transdermal, enhanced delivery 

  15. Do plasma proteins distinguish between liposomes of varying charge density?

    KAUST Repository

    Capriotti, Anna Laura

    2012-03-01

    Cationic liposomes (CLs) are one of the most employed nonviral nanovector systems in gene therapy. However, their transfection efficiency is strongly affected by interactions with plasma components, that lead to the formation of a "protein corona" onto CL surface. The interactions between nanoparticles entering the body and biomolecules have an essential role for their biodistribution. Because the knowledge of proteins adsorbed onto vector surface could be useful in the screening of new, more efficient and more biocompatible liposomal formulations, the behavior of three CLs with different membrane charge densities was investigated. The proteins of the three coronas were identified by nano-liquid chromatography-tandem mass spectrometry, and quantified with label-free spectral counting strategy. Fibrinogen displayed higher association with CLs with high membrane charge density, while apolipoproteins and C4b-binding protein with CLs with low membrane charge density. These results are discussed in terms of the different lipid compositions of CLs and may have a deep biological impact for in vivo applications. Surface charge of nanoparticles is emerging as a relevant factor determining the corona composition after interaction with plasma proteins. Remarkably, it is also shown that the charge of the protein corona formed around CLs is strongly related to their membrane charge density. © 2012 Elsevier B.V.

  16. Zoledronic acid enhances antitumor efficacy of liposomal doxorubicin.

    Science.gov (United States)

    Hattori, Yoshiyuki; Shibuya, Kazuhiko; Kojima, Kaori; Miatmoko, Andang; Kawano, Kumi; Ozaki, Kei-Ichi; Yonemochi, Etsuo

    2015-07-01

    Previously, we found that the injection of zoledronic acid (ZOL) into mice bearing tumor induced changes of the vascular structure in the tumor. In this study, we examined whether ZOL treatment could decrease interstitial fluid pressure (IFP) via change of tumor vasculature, and enhance the antitumor efficacy of liposomal doxorubicin (Doxil®). When ZOL solution was injected at 40 µg/mouse per day for three consecutive days into mice bearing murine Lewis lung carcinoma LLC tumor, depletion of macrophages in tumor tissue and decreased density of tumor vasculature were observed. Furthermore, ZOL treatments induced inflammatory cytokines such as interleukin (IL)-10 and -12, granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF)-α in serum of LLC tumor-bearing mice, but not in normal mice, indicating that ZOL treatments might induce an inflammatory response in tumor tissue. Furthermore, ZOL treatments increased antitumor activity by Doxil in mice bearing a subcutaneous LLC tumor, although they did not significantly increase the tumor accumulation of doxorubicin (DXR). These results suggest that ZOL treatments might increase the therapeutic efficacy of Doxil via improvement of DXR distribution in a tumor by changing the tumor vasculature. ZOL treatment can be an alternative approach to increase the antitumor effect of liposomal drugs.

  17. Origins of extreme boundary lubrication by phosphatidylcholine liposomes.

    Science.gov (United States)

    Sorkin, Raya; Kampf, Nir; Dror, Yael; Shimoni, Eyal; Klein, Jacob

    2013-07-01

    Phosphatidylcholine (PC) vesicles have been shown to have remarkable boundary lubricating properties under physiologically-high pressures. Here we carry out a systematic study, using a surface force balance, of the normal and shear (frictional) forces between two opposing surfaces bearing different PC vesicles across water, to elucidate the origin of these properties. Small unilamellar vesicles (SUVs, diameters < 100 nm) of the symmetric saturated diacyl PCs DMPC (C(14)), DPPC (C(16)) and DSPC (C(18)) attached to mica surfaces were studied in their solid-ordered (SO) phase on the surface. Overall liposome lubrication ability improves markedly with increasing acyl chain length, and correlates strongly with the liposomes' structural integrity on the substrate surface: DSPC-SUVs were stable on the surface, and provided extremely efficient lubrication (friction coefficient μ ≈ 10(-4)) at room temperature at pressures up to at least 18 MPa. DMPC-SUVs ruptured following adsorption, providing poor high-pressure lubrication, while DPPC-SUVs behavior was intermediate between the two. These results can be well understood in terms of the hydration-lubrication paradigm, but suggest that an earlier conjecture, that highly-efficient lubrication by PC-SUVs depended simply on their being in the SO rather than in the liquid-disordered phase, should be more nuanced. Our results indicate that the resistance of the SUVs to mechanical deformation and rupture is the dominant factor in determining their overall boundary lubrication efficiency in our system. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Liposomal Antioxidants for Protection against Oxidant-Induced Damage

    Directory of Open Access Journals (Sweden)

    Zacharias E. Suntres

    2011-01-01

    Full Text Available Reactive oxygen species (ROS, including superoxide anion, hydrogen peroxide, and hydroxyl radical, can be formed as normal products of aerobic metabolism and can be produced at elevated rates under pathophysiological conditions. Overproduction and/or insufficient removal of ROS result in significant damage to cell structure and functions. In vitro studies showed that antioxidants, when applied directly and at relatively high concentrations to cellular systems, are effective in conferring protection against the damaging actions of ROS, but results from animal and human studies showed that several antioxidants provide only modest benefit and even possible harm. Antioxidants have yet to be rendered into reliable and safe therapies because of their poor solubility, inability to cross membrane barriers, extensive first-pass metabolism, and rapid clearance from cells. There is considerable interest towards the development of drug-delivery systems that would result in the selective delivery of antioxidants to tissues in sufficient concentrations to ameliorate oxidant-induced tissue injuries. Liposomes are biocompatible, biodegradable, and nontoxic artificial phospholipid vesicles that offer the possibility of carrying hydrophilic, hydrophobic, and amphiphilic molecules. This paper focus on the use of liposomes for the delivery of antioxidants in the prevention or treatment of pathological conditions related to oxidative stress.

  19. Liposomalization of oxaliplatin induces skin accumulation of it, but negligible skin toxicity.

    Science.gov (United States)

    Nishida, Kentaro; Kashiwagi, Misaki; Shiba, Shunsuke; Muroki, Kiwamu; Ohishi, Akihiro; Doi, Yusuke; Ando, Hidenori; Ishida, Tatsuhiro; Nagasawa, Kazuki

    2017-12-15

    Liposomalization causes alteration of the pharmacokinetics of encapsulated drugs, and allows delivery to tumor tissues through passive targeting via an enhanced permeation and retention (EPR) effect. PEGylated liposomal doxorubicin (Doxil ® , Lipo-DXR), a representative liposomal drug, is well-known to reduce cardiotoxicity and increase the anti-tumor activity of DXR, but to induce the hand-foot syndrome (HFS) as a result of skin DXR accumulation, which is one of its severe adverse effects. We have developed a new liposomal preparation of oxaliplatin (l-OHP), an important anti-tumor drug for treatment of colorectal cancer, using PEGylated liposomes (Lipo-l-OHP), and showed that Lipo-l-OHP exhibits increased anti-tumor activity in tumor-bearing mice compared to the original preparation of l-OHP. However, whether Lipo-l-OHP causes HFS-like skin toxicity similar to Lipo-DXR remains to be determined. Administration of Lipo-l-OHP promoted accumulation of platinum in rat hind paws, however, it caused negligible morphological and histological alterations on the plantar surface of the paws. Administration of DiI-labeled empty PEGylated liposomes gave almost the same distribution profile of dyes into the dermis of hind paws with DXR as in the case of Lipo-DXR. Treatment with Lipo-l-OHP, Lipo-DXR, DiI-labeled empty PEGylated liposomes or empty PEGylated liposomes caused migration of CD68 + macrophages into the dermis of hind paws. These findings suggest that the skin toxicity on administration of liposomalized drugs is reflected in the proinflammatory characteristics of encapsulated drugs, and indicate that Lipo-l-OHP with a higher anti-cancer effect and no HFS may be an outstanding l-OHP preparation leading to an improved quality of life of cancer patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Liposomal Fasudil, a Rho-Kinase Inhibitor, for Prolonged Pulmonary Preferential Vasodilation in Pulmonary Arterial Hypertension

    Science.gov (United States)

    Gupta, Vivek; Gupta, Nilesh; Shaik, Imam H.; Mehvar, Reza; McMurtry, Ivan F.; Oka, Masahiko; Nozik-Grayck, Eva; Komatsu, Masanobu; Ahsan, Fakhrul

    2013-01-01

    Current pharmacological interventions for pulmonary arterial hypertension (PAH) require continuous infusions, multiple inhalations, or oral administration of drugs that act on various pathways involved in the pathogenesis of PAH. However, invasive methods of administration, short duration of action, and lack of pulmonary selectivity result in noncompliance and poor patient outcomes. In this study, we tested the hypothesis that encapsulation of an investigational anti-PAH molecule fasudil (HA-1077), a Rho-kinase inhibitor, into liposomal vesicles results in prolonged vasodilation in distal pulmonary arterioles. Liposomes were prepared by hydration and extrusion method and fasudil was loaded by ammonium sulfate-induced transmembrane electrochemical gradient. Liposomes were then characterized for various physicochemical properties. Optimized formulations were tested for pulmonary absorption and their pharmacological efficacy in a monocrotaline (MCT) induced rat model of PAH. The entrapment efficiency of optimized liposomal fasudil formulations was between 68.1±0.8% and 73.6±2.3%, and the cumulative release at 37°C was 98–99% over a period of 5 days. Compared to intravenous (IV) fasudil, a ~10 fold increase in the terminal plasma half-life was observed when liposomal fasudil was administered as aerosols. The t1/2 of IV fasudil was 0.39±0.12 h. and when given as liposomes via pulmonary route, the t1/2 extended to 4.71±0.72 h. One h after intratracheal instillation of liposomal fasudil, mean pulmonary arterial pressure (MPAP) was reduced by 37.6±5.7% and continued to decrease for about 3 h, suggesting that liposomal formulations produced pulmonary preferential vasodilation in MCT induced PAH rats. Overall, this study established the proof-of-principle that aerosolized liposomal fasudil is a feasible option for a non-invasive, controlled release and pulmonary preferential treatment of PAH. PMID:23353807

  1. Liposomes coated with hydrophobically modified hydroxyethyl cellulose: Influence of hydrophobic chain length and degree of modification.

    Science.gov (United States)

    Smistad, Gro; Nyström, Bo; Zhu, Kaizheng; Grønvold, Marthe Karoline; Røv-Johnsen, Anne; Hiorth, Marianne

    2017-08-01

    Nanoparticulate systems with an uncharged hydrophilic surface may have a great potential in mucosal drug delivery. In the present study liposomes were coated with hydrophobically modified hydroxyethyl cellulose (HM-HEC) to create a sterically stabilized liposomal system with an uncharged surface. The aim was to clarify the influence of the amount of hydrophobic modification of HEC and the length of the hydrophobic moiety, on the stability of the system and on the release properties. HM-HEC with different degrees of hydrophobic modification (1 and 2mol%) and hydrophobic groups with different chain lengths (C8, C12, C16) were included in the study, as well as fluid phase and gel phase liposomes. Both types of liposomes were successfully coated with HM-HEC containing 1mol% of hydrophobic groups, while 2mol% did not work for the intended pharmaceutical applications. The polymer coated gel phase liposomes were stable (size, zeta potential, leakage) for 24 weeks at 4°C, with no differences between the C8 and C16 HM-HEC coating. For the fluid phase liposomes a size increase was observed after 24 weeks at 4°C for all formulations; the C8 HM-HEC coated liposomes increased the most. No differences in the leakage during storage at 4°C or in the release at 35°C were observed between the fluid phase formulations. To conclude; HM-HEC with a shorter hydrophobic chain length resulted in a less stable product for the fluid phase liposomes, while no influence of the chain length was observed for the gel phase liposomes (1mol% HM). Copyright © 2017 Elsevier B.V. All rights reserved.

  2. 6-mercaptopurine (6-MP) entrapped stealth liposomes for improvement of leukemic treatment without hepatotoxicity and nephrotoxicity.

    Science.gov (United States)

    Umrethia, Manish; Ghosh, Pradip Kumar; Majithya, Rita; Murthy, R S R

    2007-03-01

    6-mercaptopurine (6-MP) is a purine analogue used in childhood leukemia. Because of the oral bioavailability of 6-MP is low and highly variable, the aim of this study was to develop a new parenteral formulation that can prolong the biological half-life of the drug, improve its therapeutic efficacy, and its associated reduce side effects. Conventional and stealth 6-MP liposomes were prepared by a thin film hydration technique followed by a high-pressure homogenization process and characterized for percent entrapment efficiency (%EE), particle size, and stability in human plasma. Pharmacokinetic, tissue distribution, and biochemical analysis were performed after intravenous (IV) administration of all formulations of 6-MP on rats. The conventional liposomes were found less stable than stealth liposomes in human plasma at 37 degrees C. Stealth liposomes exhibited high peak plasma concentration (C(max)), and long circulating capacity in blood and biological half-life. The uptake of stealth liposomes by the liver and spleen and accumulation in the kidney were significantly less than that of conventional liposomes and the free drug. Serum urea, creatinine, GOT (Glutamic Oxaloacetic Transaminase), and GPT (Glutamic Pyruvic Transaminase) increased significantly in rats given an IV injection of conventional liposomes and the free drug, but not in those administered with the same dose of stealth liposomes. Stealth liposomes may help to increase therapeutic efficacy of 6-MP and to reduce total amount of dose as well as frequency of the dose. It also may reduce the possibility of the risk of toxicity to the liver and kidney generally associated with free 6-MP.

  3. The effect of reticuloendothelial blockade on the blood clearance and tissue distribution of liposomes

    International Nuclear Information System (INIS)

    Souhami, R.L.; Patel, H.M.; Ryman, B.E.

    1981-01-01

    The blood clearance and tissue distribution of liposomes have been studied in mice subjected to reticuloendothelial blockade with dextran sulphate or carbon. The liposomes have been labelled in the lipid membranes with [ 3 H]-cholesterol, [ 14 C]phosphatidylcholine and/or 99 sup(m)Tc and the content with [ 14 C]inulin. Reticuloendothelial blockade has been shown to slow the rate of clearance of neutral, positively and negatively charged liposomes and of both small unilamellar vesicles and large multilamellar vesicles. In normal animals, the liver uptake accounted for only 20-55% of the total injected radioactivity, the amount varying with the charge and size of the liposomes. Following blockade, the liver uptake of charged and neutral multilamellar liposomes was depressed. This was also true for negatively charged small unilamellar vesicles. The degree of depression of hepatic uptake was between 25-50%, which contrasts with the 80-90% reduction in uptake of a wholly phagocytosed particle (sheep red cells). This difference suggets that mechanisms other than Kupffer cell phagocytosis are also responsible for the normal uptake of liposomes into the liver. In the case of neutral and positively charged small unilamellar vesicles, delayed clearance due to blockade was not associated with depressed hepatic uptake. The site of action of blockading agents for these preparations is not clear. With all preparations of liposomes, blockade produced a slight and variable increase in uptake in the lung and spleen. The alteration of distribution of liposomes by reticuloendothelial blockade is therefore not great and the value of the technique in modifying the tissue distribution of substances within liposomes may be limited. (orig.)

  4. Encapsulation of Liposomes within pH Responsive Microspheres for Oral Colonic Drug Delivery

    Directory of Open Access Journals (Sweden)

    M. J. Barea

    2012-01-01

    Full Text Available A novel liposome-in-microsphere (LIM formulation has been created comprising drug-loaded liposomes within pH responsive Eudragit S100 microspheres. The liposomes contained the model drug 5-ASA and were coated with chitosan in order to protect them during encapsulation within the microspheres and to improve site-specific release characteristics. In vitro drug release studies showed that LIMs prevented drug release within simulated stomach and small intestine conditions with subsequent drug release occurring in large intestine conditions. The formulation therefore has potential for oral colonic drug delivery.

  5. Liposomes coated with thiolated chitosan enhance oral peptide delivery to rats☆

    Science.gov (United States)

    Gradauer, K.; Barthelmes, J.; Vonach, C.; Almer, G.; Mangge, H.; Teubl, B.; Roblegg, E.; Dünnhaupt, S.; Fröhlich, E.; Bernkop-Schnürch, A.; Prassl, R.

    2013-01-01

    The aim of the present study was the in vivo evaluation of thiomer-coated liposomes for an oral application of peptides. For this purpose, salmon calcitonin was chosen as a model drug and encapsulated within liposomes. Subsequently, the drug loaded liposomes were coated with either chitosan–thioglycolic acid (CS–TGA) or an S-protected version of the same polymer (CS–TGA–MNA), leading to an increase in the particle size of about 500 nm and an increase in the zeta potential from approximately − 40 mV to a maximum value of about + 44 mV, depending on the polymer. Coated liposomes were demonstrated to effectively penetrate the intestinal mucus layer where they came in close contact with the underlying epithelium. To investigate the permeation enhancing properties of the coated liposomes ex vivo, we monitored the transport of fluoresceinisothiocyanate-labeled salmon calcitonin (FITC-sCT) through rat small intestine. Liposomes coated with CS–TGA–MNA showed the highest effect, leading to a 3.8-fold increase in the uptake of FITC-sCT versus the buffer control. In vivo evaluation of the different formulations was carried out by the oral application of 40 μg of sCT per rat, either encapsulated within uncoated liposomes, CS–TGA-coated liposomes or CS–TGA–MNA-coated liposomes, or given as a solution serving as negative control. The blood calcium level was monitored over a time period of 24 h. The highest reduction in the blood calcium level, to a minimum of 65% of the initial value after 6 h, was achieved for CS–TGA–MNA-coated liposomes. Comparing the areas above curves (AAC) of the blood calcium levels, CS–TGA–MNA-coated liposomes led to an 8.2-fold increase compared to the free sCT solution if applied orally in the same concentration. According to these results, liposomes coated with S-protected thiomers have demonstrated to be highly valuable carriers for enhancing the oral bioavailability of salmon calcitonin. PMID:24140721

  6. Liposomes coated with thiolated chitosan enhance oral peptide delivery to rats.

    Science.gov (United States)

    Gradauer, K; Barthelmes, J; Vonach, C; Almer, G; Mangge, H; Teubl, B; Roblegg, E; Dünnhaupt, S; Fröhlich, E; Bernkop-Schnürch, A; Prassl, R

    2013-12-28

    The aim of the present study was the in vivo evaluation of thiomer-coated liposomes for an oral application of peptides. For this purpose, salmon calcitonin was chosen as a model drug and encapsulated within liposomes. Subsequently, the drug loaded liposomes were coated with either chitosan-thioglycolic acid (CS-TGA) or an S-protected version of the same polymer (CS-TGA-MNA), leading to an increase in the particle size of about 500 nm and an increase in the zeta potential from approximately -40 mV to a maximum value of about +44 mV, depending on the polymer. Coated liposomes were demonstrated to effectively penetrate the intestinal mucus layer where they came in close contact with the underlying epithelium. To investigate the permeation enhancing properties of the coated liposomes ex vivo, we monitored the transport of fluoresceinisothiocyanate-labeled salmon calcitonin (FITC-sCT) through rat small intestine. Liposomes coated with CS-TGA-MNA showed the highest effect, leading to a 3.8-fold increase in the uptake of FITC-sCT versus the buffer control. In vivo evaluation of the different formulations was carried out by the oral application of 40 μg of sCT per rat, either encapsulated within uncoated liposomes, CS-TGA-coated liposomes or CS-TGA-MNA-coated liposomes, or given as a solution serving as negative control. The blood calcium level was monitored over a time period of 24h. The highest reduction in the blood calcium level, to a minimum of 65% of the initial value after 6h, was achieved for CS-TGA-MNA-coated liposomes. Comparing the areas above curves (AAC) of the blood calcium levels, CS-TGA-MNA-coated liposomes led to an 8.2-fold increase compared to the free sCT solution if applied orally in the same concentration. According to these results, liposomes coated with S-protected thiomers have demonstrated to be highly valuable carriers for enhancing the oral bioavailability of salmon calcitonin. © 2013. Published by Elsevier B.V. All rights reserved.

  7. Successful haploidentical stem cell transplantation with prophylactic administration of liposomal amphotericin B after invasive pulmonary zygomycosis

    Directory of Open Access Journals (Sweden)

    Testuro Ochi

    2017-12-01

    Full Text Available A 54-year-old woman with acute myeloid leukemia (AML achieved complete remission by induction chemotherapy, but developed zygomycosis after consolidation therapy. As zygomycosis could not be cured by liposomal amphotericin B and micafungin, left lower lobectomy was performed. As AML relapsed 7 months after onset, she received haploidentical stem cell transplantation under administration of liposomal amphotericin B. Despite experiencing severe acute graft-versus-host disease, she remains alive with no relapse of either zygomycosis or AML. Keywords: Zygomycosis, Acute myeloid leukemia, Liposomal amphotericin B, Stem cell transplantation

  8. Modification of radiation-induced oxidative damage in liposomal and microsomal membrane by eugenol

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, B.N. [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Lathika, K.M. [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Mishra, K.P. [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)]. E-mail: kpm@magnum.barc.ernet.in

    2006-03-15

    Radiation-induced membrane oxidative damage, and their modification by eugenol, a natural antioxidant, was investigated in liposomes and microsomes. Liposomes prepared with DPH showed decrease in fluorescence after {gamma}-irradiation, which was prevented significantly by eugenol and correlated with magnitude of oxidation of phospholipids. Presence of eugenol resulted in substantial inhibition in MDA formation in irradiated liposomes/microsomes, which was less effective when added after irradiation. Similarly, the increase in phospholipase C activity observed after irradiation in microsomes was inhibited in samples pre-treated with eugenol. Results suggest association of radio- oxidative membrane damage with alterations in signaling molecules, and eugenol significantly prevented these membrane damaging events.

  9. Construction of a liposome dialyzer for the preparation of high-value, small-volume liposome formulations.

    Science.gov (United States)

    Adamala, Katarzyna; Engelhart, Aaron E; Kamat, Neha P; Jin, Lin; Szostak, Jack W

    2015-06-01

    The liposome dialyzer is a small-volume equilibrium dialysis device, built from commercially available materials, that is designed for the rapid exchange of small volumes of an extraliposomal reagent pool against a liposome preparation. The dialyzer is prepared by modification of commercially available dialysis cartridges (Slide-A-Lyzer cassettes), and it consists of a reactor with two 300-μl chambers and a 1.56-cm(2) dialysis surface area. The dialyzer is prepared in three stages: (i) disassembling the dialysis cartridges to obtain the required parts, (ii) assembling the dialyzer and (iii) sealing the dialyzer with epoxy. Preparation of the dialyzer takes ∼1.5 h, not including overnight epoxy curing. Each round of dialysis takes 1-24 h, depending on the analyte and membrane used. We previously used the dialyzer for small-volume non-enzymatic RNA synthesis reactions inside fatty acid vesicles. In this protocol, we demonstrate other applications, including removal of unencapsulated calcein from vesicles, remote loading and vesicle microscopy.

  10. Microneedle-assisted delivery of verapamil hydrochloride and amlodipine besylate.

    Science.gov (United States)

    Kaur, Monika; Ita, Kevin B; Popova, Inna E; Parikh, Sanjai J; Bair, Daniel A

    2014-02-01

    The aim of this project was to study the effect of stainless steel solid microneedles and microneedle rollers on percutaneous penetration of verapamil hydrochloride and amlodipine besylate. Verapamil, 2-(3,4-dimethooxyphenyl)-5-[2-(3,4 dimethoxyphenyl)ethyl-methyl-amino]-2-propan-2-yl-pentanenitrile is a calcium channel blocker agent that regulates high blood pressure by decreasing myocardial contractilty, heart rate and impulse conduction. Amlodipine, (R, S)-2-[(2-aminoethoxy) methyl]-4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-1, 4-dihydropyridine, is a calcium channel blocker that is used for the management of hypertension and ischemic heart disease. Passive penetration of verapamil and amlodipine across the skin is low. In vitro studies were performed with microneedle-treated porcine ear skin using vertical static Franz diffusion cells (PermeGear, Hellertown, PA, USA). The receiver chamber contained 5ml of PBS (pH7.4) and was constantly maintained at 37°C temperature with a water circulation jacket. The diffusion area of the skin was 1.77cm(2). The donor compartment was loaded with 1ml of the solution containing 2.5mg/ml of amlodipine besylate. The donor chamber was covered with parafilm to avoid evaporation. Passive diffusion across untreated porcine skin served as control. Aliquots were taken every 2h for 12h and analyzed by liquid chromatography-mass spectrometry. Transcutaneous flux of verapamil increased significantly from 8.75μg/cm(2)/h to 49.96μg/cm(2)/h across microneedle-roller treated porcine skin. Percutaneous flux of amlodipine besylate following the use of stainless steel microneedles was 22.39μg/cm(2)/h. Passive flux for the drug was 1.57μg/cm(2)/h. This enhancement of amlodipine flux was statistically significant. Transdermal flux of amlodipine with microneedle roller was 1.05μg/cm(2)/h in comparison with passive diffusion flux of 0.19μg/cm(2)/h. The difference in flux values was also statistically significant. Stainless

  11. Radiolabeling of liposomes and polymeric micelles with PET-isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Ingemann Jensen, A.T.

    2013-06-01

    This thesis is divided into three separate chapters that can be read independently. Chapter 1 is a general introduction, touching upon liposomes and polymeric micelles and radiolabeling with 18F and 64Cu. Chapter 2 and 3 address two separate research projects, each described below. A complete reference list is compiled in the end, immediately after the three chapters. This is followed by the supplementary information, divided into appropriate sections. Finally, the two first-authored manuscripts are attached as appendices. Chapter 1. The field of nanoparticulate drug delivery has been hailed as a revolution in modern therapeutics, especially in chemotherapy. A major reason is the ability of nanoparticles to accumulate in tumor tissue. Liposomes are the classic nanoparticle, consisting of a lipid membrane with an aqueous core. Polymeric micelles are made from amphiphilic detergent-like copolymers, that self-assemble in water. Therapy with nanoparticles is hampered by often poor tumor accumulation, combined with massive uptake by macrophages in the liver and spleen. For this reason, visualizing nanoparticle pharmacokinetics in-vivo is a valuable tool in the on-going research. Such visualization can be done by labeling with radio isotopes. Isotopes that emit positrons (PET-isotopes) can be detected by PET (positron emission tomography) technology, an accurate technique that has gained popularity in recent years. PET-isotopes of interest include 18F and 64Cu. In addition to being a research tool, radiolabeled nanoparticles hold promise as a radiopharmaceutical in themselves, as a means of imaging tumor tissue, aiding in diagnosis and surgery. Chapter 2. A method for labeling liposomes with 18F (97% positron decay, T = 110 min) was investigated. 18F is widely available, but is hampered by a short half-life only allowing up to 8 hours scans. 18F must be covalently attached to components of the liposome. By binding to a lipid, it can be stably lodged in the membrane. A

  12. Radiolabeling of liposomes and polymeric micelles with PET-isotopes

    International Nuclear Information System (INIS)

    Ingemann Jensen, A.T.

    2013-01-01

    This thesis is divided into three separate chapters that can be read independently. Chapter 1 is a general introduction, touching upon liposomes and polymeric micelles and radiolabeling with 18F and 64Cu. Chapter 2 and 3 address two separate research projects, each described below. A complete reference list is compiled in the end, immediately after the three chapters. This is followed by the supplementary information, divided into appropriate sections. Finally, the two first-authored manuscripts are attached as appendices. Chapter 1. The field of nanoparticulate drug delivery has been hailed as a revolution in modern therapeutics, especially in chemotherapy. A major reason is the ability of nanoparticles to accumulate in tumor tissue. Liposomes are the classic nanoparticle, consisting of a lipid membrane with an aqueous core. Polymeric micelles are made from amphiphilic detergent-like copolymers, that self-assemble in water. Therapy with nanoparticles is hampered by often poor tumor accumulation, combined with massive uptake by macrophages in the liver and spleen. For this reason, visualizing nanoparticle pharmacokinetics in-vivo is a valuable tool in the on-going research. Such visualization can be done by labeling with radio isotopes. Isotopes that emit positrons (PET-isotopes) can be detected by PET (positron emission tomography) technology, an accurate technique that has gained popularity in recent years. PET-isotopes of interest include 18F and 64Cu. In addition to being a research tool, radiolabeled nanoparticles hold promise as a radiopharmaceutical in themselves, as a means of imaging tumor tissue, aiding in diagnosis and surgery. Chapter 2. A method for labeling liposomes with 18F (97% positron decay, T = 110 min) was investigated. 18F is widely available, but is hampered by a short half-life only allowing up to 8 hours scans. 18F must be covalently attached to components of the liposome. By binding to a lipid, it can be stably lodged in the membrane. A

  13. Internal radiotherapy and dosimetric study for 111In/177Lu-pegylated liposomes conjugates in tumor-bearing mice

    International Nuclear Information System (INIS)

    Wang, H.-E.; Yu, H.-M.; Lu, Y.-C.; Heish, N.-N.; Tseng, Yun-Long; Huang, K.-L.; Chuang, K.-T.; Chen, Chin-Hsiung; Hwang, J.-J.; Lin, W.-J.; Wang, Shyh-Jen; Ting, G.; Whang-Peng, Jacqueline; Deng, W.-P.

    2006-01-01

    In vivo characterization and dosimetric analysis has been performed to evaluate the potential of pegylated liposomes as carriers of radionuclides in tumor internal radiotherapy. Methods: The DTPA/PEG-liposomes were synthesized with a medium size of 110 nm, conjugated with 111 In/ 177 Lu-(oxine) 3 to afford 111 In/ 177 Lu-liposome. The stability of 111 In/ 177 Lu-liposome in serum was investigated. The biodistribution, scintigraphic imaging and pharmacokinetics of 111 In/ 177 Lu-liposomes after intravenous(i.v.) injection into C-26 tumor-bearing BALB/cByJ mice were studied. Radiation dose was estimated by MIRD-III program. Results: The incorporation efficiency of 111 In/ 177 Lu into liposomes was 95%. After incubation at 37 o C for 72 h in serum, more than 83% of radioactivity was still retained in the intact 111 In/ 177 Lu-liposomes. The biodistribution of 111 In-liposomes showed that the radioactivity in the blood decreased from 23.14±8.16%ID/g at 1 h to 0.02±0.00%ID/g at 72 h post-injection (p.i.), while reaching its maximum accumulation in tumors at 48 h p.i., with half-life in blood of 10.2 h. The results were supported by that of 177 Lu-liposomes. Scintigraphic imaging with 111 In-liposomes showed unambiguous tumor images at 48 h p.i. Dose estimation showed that the absorbed dose in tumor from 177 Lu-liposomes was 5.74x10 -5 Gy/MBq. Conclusions: This study provides an in vivo characterization and dosimetric evaluation for the use of liposome systems as carriers in targeted radionuclide therapy. The results suggest that adequate tumor targeting as well as dose delivered to tumors could be achieved by the use of radionuclide targeted liposomes

  14. High Performace Liquid Chromtographic Determination of Nicardipine Hydrochloride in Human Plasma

    Directory of Open Access Journals (Sweden)

    Y. S. R. Krishnaiah

    2004-01-01

    Full Text Available A sensitive high-performance liquid chromatographic method was developed for the estimation of nicardipine hydrochloride in human plasma. Varying amount of nicardipine hydrochloride (2.5 to 150 ng/0.5 mL and fixed quantity (100 ng/0.5 mL of nifedipine (internal standard was added to blank human plasma, and a single step extraction was carried out with ethyl acetate. The mixture was centrifuged, ethyl acetate layer separated, dried and reconstituted with 100 μL of acetonitrile. Twenty microliters of this solution was injected into a reverse phase C-18 column using a mobile phase consisting of acetonitrile: 0.02 M potassium dihydrogen phosphate (pH 4.0 in the ratio of 60:40 v/v and the eluents were monitored at 239 nm. The method was validated for its linearity, precision and accuracy. The calibration curve was linear in the range of 5-150 ng/0.5 mL of plasma and the lower detection limit was 2.5 ng/0.5 mL of plasma. The intra- and inter-day variation was found to be less than 2.5% indicating that the method is highly precise. The mean recovery of nicardipine hydrochloride from plasma samples was 89.6±2.60%. The proposed HPLC method was applied for the estimation of nicardipine hydrochloride in human plasma after oral administration of an immediate release nicardipine hydrochloride capsule (dose 30 mg to 6 adult male volunteers. There was no interference of either the drug metabolites or other plasma components with the proposed HPLC method for the estimation of nicardipine hydrochloride in human plasma. Due to its simplicity, sensitivity, high precision and accuracy, the proposed HPLC method may be used for biopharmaceutical and pharmacokinetic evaluation of nicardipine hydrochloride and its formulations in humans

  15. Human serum paraoxonase-1 (hPON1): in vitro inhibition effects of moxifloxacin hydrochloride, levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium.

    Science.gov (United States)

    Türkeş, Cüneyt; Söyüt, Hakan; Beydemir, Şükrü

    2015-01-01

    In this study, we investigated the effects of antibacterial drugs (moxifloxacin hydrochloride, levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium) on human serum paraoxonase-1 (hPON1) enzyme activity from human serum in vitro conditions. For this purpose, hPON1 enzyme was purified from human serum using simple chromatographic methods. The antibacterial drugs exhibited inhibitory effects on hPON1 at low concentrations. Ki constants were calculated to be 2.641 ± 0.040 mM, 5.525 ± 0.817 mM, 35.092 ± 1.093 mM, 252.762 ± 5.749 mM and 499.244 ± 10.149 mM, respectively. The inhibition mechanism of moxifloxacin hydrochloride was competitive, whereas levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium were noncompetitive inhibitors.

  16. Liposomes and nanotechnology in drug development: focus on oncotargets

    Directory of Open Access Journals (Sweden)

    Kozako T

    2012-09-01

    Full Text Available Tomohiro Kozako,1 Naomichi Arima,2 Makoto Yoshimitsu,3 Shin-Ichro Honda,1 Shinji Soeda11Department of Biochemistry, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan; 2Division of Hematology and Immunology, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan; 3Department of Hematology and Immunology, Kagoshima University Hospital, Kagoshima, JapanAbstract: Nanotechnology is the development of an engineered device at the atomic, molecular, and macromolecular level in the nanometer range. Advances in nanotechnology have proven beneficial in therapeutic fields such as drug-delivery and gene/protein delivery. Antigen delivery systems are important for inducing and modifying immune responses. In cellular immunity, cytotoxic T lymphocytes (CTLs are important in the host defense against tumors. Key to the development of CTL-inducible vaccines is the ability to deliver antigens to antigen-presenting cells efficiently and to induce the subsequent activation of T cell-mediated immunity without adjuvants, as they can induce excessive inflammation leading to systemic febrile disease. Since expression and cloning methods for tumor-associated antigens have been reported, cancer vaccines that induce effective cell immunity may be promising therapeutic candidates, but Th2 cells are undesirable for use in cancer immunotherapy. Peptide vaccines have immunological and economic advantages as cancer vaccines because CTL epitope peptides from tumor-associated antigens have high antigen-specificity. However, cancer vaccines have had limited effectiveness in clinical responses due to the ability of cancer cells to “escape” from cancer immunity and a low efficiency of antigen-specific CTL induction due to immunogenic-free synthetic peptides. In contrast, carbohydrate-decorated particles such as carbohydrate-coated liposomes with encapsulated antigens might be more suitable as

  17. Prednisone and vardenafil hydrochloride for refractory levamisole-induced vasculitis.

    Science.gov (United States)

    Mandrell, Joshua; Kranc, Christina L

    2016-08-01

    Levamisole is an immunomodulatory drug that was previously used to treat various medical conditions, including parasitic infections, nephrotic syndrome, and colorectal cancer. Over the last few years, increasing amounts of levamisole have been used as an adulterant in cocaine. Levamisole-cut cocaine has become a concern because it is known to cause a necrotizing purpuric rash, autoantibody production, and life-threatening leukopenia. Mixed histologic findings of vasculitis and thrombosis are characteristic of levamisole-induced purpura. The recommended management of levamisole-induced vasculitis currently involves withdrawal of the culprit along with supportive treatment. We describe a patient with levamisole-induced vasculitis who continued to develop skin lesions despite self-reported cocaine cessation. Complete resolution of cutaneous disease occurred with the addition of oral prednisone and vardenafil hydrochloride, suggesting the possibility of a new treatment option in patients with refractory disease. In addition, we review the clinical presentation, disease course, diagnostic approach, laboratory findings, histology, and management of levamisole-induced vasculitis. The harmful effects of levamisole-cut cocaine are serious enough that public alerts have been issued to increase awareness. Clinicians should consider the possibility of levamisole exposure in cocaine users presenting with any combination of fever, neutropenia, and necrotic skin lesions, especially in acral areas including the ears.

  18. Adsorptive stripping voltammetric determination of triprolidine hydrochloride in pharmaceutical tablets.

    Science.gov (United States)

    Zayed, S I M; Habib, I H I

    2005-01-01

    The electrochemical behavior of antihistaminic drug, viz. triprolidine hydrochloride (TripCl), at a hanging mercury drop electrode (HMDE) is investigated. Chemical and electrical parameters affecting the adsorptive voltammetric measurements are optimized. Different modes of sweep, viz. direct current DC, normal pulse NP, differential pulse DP and square wave SW modes, over the potential range from -800 to -1400 mV, are used in the presence of 0.04 M Britton-Robinson buffer pH 11, with accumulation time 30 s, scan rate 50 mV/s and pulse amplitude 50 mV. The reduction process is irreversible and involved the transfer of two electrons and two protons. Their responses are linear over the concentration range 15-157 ng/ml with average correlation coefficient 0.9998, while the detection limit is 2.64, 6.24, 8.80 and 2.12 ng/ml for DC, DP, SW and NP mode, respectively. The differential pulse method has been applied successfully for the determination of the drug in Egyptian pharmaceutical preparation with mean recovery 99.55+/-0.67%.

  19. Development and evaluation of microporous osmotic tablets of diltiazem hydrochloride

    Directory of Open Access Journals (Sweden)

    Afifa Bathool

    2012-01-01

    Full Text Available Microporous osmotic tablet of diltiazem hydrochloride was developed for colon targeting. These prepared microporous osmotic pump tablet did not require laser drilling to deliver the drug to the specific site of action. The tablets were prepared by wet granulation method. The prepared tablets were coated with microporous semipermeable membrane and enteric polymer using conventional pan coating process. The incorporation of sodium lauryl sulfate (SLS, a leachable pore-forming agent, could form in situ delivery pores while coming in contact with gastrointestinal medium. The effect of formulation variables was studied by changing the amounts of sodium alginate and NaCMC in the tablet core, osmogen, and that of pore-forming agent (SLS used in the semipermeable coating. As the amount of hydrophilic polymers increased, drug release rate prolonged. It was found that drug release was increased as the concentration of osmogen and pore-former was increased. Fourier transform infrared spectroscopy and Differential scanning calorimetry results showed that there was no interaction between drug and polymers. Scanning electron microscopic studies showed the formation of pores after predetermined time of coming in contact with dissolution medium. The formation of pores was dependent on the amount of pore former used in the semipermeable membrane. in vitro results showed acid-resistant, timed release at an almost zero order up to 24 hours. The developed osmotic tablets could be effectively used for prolonged delivery of Diltiazem HCl.

  20. Prevention of venous pain and phlebitis caused by epirubicin hydrochloride.

    Science.gov (United States)

    Sugimoto, Masakazu; Matsui, Masateru; Harada, Masanori; Yamauchi, Yumiko; Moriyama, Nao; Andou, Kanae; Yamamoto, Makoto; Yamaoka, Hisayo; Ono, Chiemi; Ishikawa, Mami; Kamo, Nobuyuki; Ikeda, Tadashi; Yamaoka, Keiko

    2009-06-01

    Many patients complain of venous pain or develop phlebitis following treatment with epirubicin hydrochloride(EPI). To ensure effective and safe treatment with this drug, it is essential to deal with the adverse events associated with it appropriately. At our hospital, EPI was previously administered by drip infusion(diluted with 50mL of physiological saline)over 15 minutes after pretreatment(EPI main route). With this method of treatment, venous pain and phlebitis developed in 14 of 15 cases. In 3 of these 14 cases, the regimen was modified. Following this experience, EPI administration was switched to drip infusion from the fully-opened side tube used for pretreatment(EPI sub-route). Switching to this route resulted in a sharp decrease in the incidence of venous pain and phlebitis, to only 1 of 15 cases. Stimulation of vascular tunica intima by EPI has been considered a factor principally responsible for the venous pain and phlebitis seen after EPI therapy. To prevent these adverse reactions, it is necessary to modify the method of administration so that strong or long-term exposure of blood vessels to EPI can be reduced. The results of this study suggest that the EPI sub-route we devised is useful in achieving this goal.