scholarly journals The THE INFLUENCE OF CHLORPROMAZINE HYDROCHLORIDE ON THE SIZE OF SMALL UNILAMELLAR DIMYROSTYLPHOSPHATIDYLCHOLINE LIPOSOMES AS REVEALED BY LIGHT SCATTERING PHOTOMETRY

2019 ◽  
pp. 76-82
Author(s):  
Farah hamad Ahmed
Keyword(s):  
Light Scattering ◽  
Critical Micelle Concentration ◽  
Gradual Increase ◽  
Elution Profile ◽  
Lipid Film ◽  
Chlorpromazine Hydrochloride ◽  
Dimyristoyl Phosphatidylcholine ◽  
Multilamellar Liposomes ◽  
Surface Active ◽  
Hcl Concentration

Objectives: This study aims to investigate the possible influence of the model, cationic, surface-active solute chlorpromazine hydrochloride (CPZ-HCl) on the size of small unilamellar dimyristoyl phosphatidylcholine (DMPC) liposomes as a function of temperature and CPZ-HCl concentration, below and above the critical micelle concentration (CMC). Methods: Small unilamellar DMPC liposomes were prepared by dissolving DMPC in chloroform and the solvent was rota-evaporated in a water bath adjusted at 40 °C. The lipid film was then dispersed in 0.1 M KCl solution adjusted at pH 6.2 to form large multilamellar liposomes which are then sonicated and fractionated via Sepharose 2B-Cl gel. The elution profile was followed spectrophotometrically at λ 260 nm. Combined fractions from the trailing edge of the included peak which is due to small unilamellar liposomes, were used as a source throughout this study. The SOFICA light scattering photometer (Model 42000) was used to determine the weight average liposomes weight (Lw) of small unilamellar DMPC liposomes. The Lw was determined in the absence and presence of CPZ-HCl both above and below the CMC over the temperature range of 25 °C to 40 °C. Results: The Lw was observed to increase linearly in the absence and presence of CPZ-HCl. The Lw was observed to increase linearly in the absence of CPZ-HCl, from 1.88×106+0.02 g/mol at 25 °C to 3.25×106+0.03 g/mol at 40 °C. Similarly, the Lw was observed to increase linearly in the present of CPZ-HCl, for example at 18 mmol drug concentration, the Lw increases from 11×106+0.04 g/mol at 25 °C to 13.75×106+0.03 g/mol at 40 °C. When the data are presented as a function of CPZ-HCl concentration, a gradual increase in Lw was observed below the CMC. Little increase in Lw however, was observed at post-micellar concentrations of 14 mmol and 18 mmol.

scholarly journals Kinetic Study of Peroxidase-Catalyzed Oxidation of 2-Hydroxyanthracene and 9-Phenanthrol in Presence of Biosurfactant Escin

Catalysts ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 591
Author(s):  
Rūta Ivanec-Goranina
Keyword(s):  
Light Scattering ◽  
Critical Micelle Concentration ◽  
Dynamic Light Scattering ◽  
Kinetic Measurements ◽  
Scattering Technique ◽  
Dynamic Light Scattering Technique ◽  
Kinetics Of ◽  
Catalyzed Oxidation ◽  
Environmentally Friendly Method ◽  
Light Scattering Technique

The kinetics of fungal peroxidase-catalyzed 2-hydroxyanthracene and 9-phenanthrol oxidation was investigated in presence of biosurfactant escin at pH 5.5 and 25 °C. The kinetic measurements were performed using the fluorimetric method and the critical micelle concentration (CMC) of escin was determined using the dynamic light scattering technique. Inactivation of peroxidase was observed in absence of biosurfactant escin. It was shown that escin, used in concentrations lower than CMC, decreases or completely stops the peroxidase inactivation and increases the conversion of 2-hydroxyanthracene as well as of 9-phenanthrol. The environmentally friendly method of peroxidase-catalyzed 2-hydroxyanthracene and 9-phenanthrol oxidation in presence of biosurfactant Escin has an advantage over traditional decontamination methods due to their less environmental impact.

The study on Characteristics of Surface-Active Polymer

2011 ◽  
Vol 393-395 ◽  
pp. 1574-1578
Author(s):  
Yan Fen Sui
Keyword(s):  
Critical Micelle Concentration ◽  
Adsorption Capacity ◽  
Retention Volume ◽  
Polymer Surface ◽  
Surface Adsorption ◽  
High Viscosity ◽  
Molecular Weight Polymer ◽  
New Type ◽  
Surface Active ◽  
Polymer Retention

Through the indoor comparative experiments, this paper studied the viscosity and surface tension of surface-active polymer, and calculated the critical micelle concentration, the surface adsorption capacity, molecular occupied area, and other parameters. Through comparing with intermediate molecular weight polymer, it is found out that surface-active polymer has characteristics of high viscosity and its viscosity is higher than common polymer under the same concentration. As a new type of polymer, surface-active polymer can reduce the tension and present a certain activity. The critical micelle concentration of surface-active polymer is 0.2532 g/L, the surface adsorption capacity is 1.678×10 -10mol.cm -2,and the molecule occupies an area of 0.9899 nm 2 .This theme also studied the emulsifying power and the characteristic of static and dynamic adsorption. The results show that the agents have approved emulsifying power with only 38% of the excluded water during 30 days. The static adsorption capacity of surface-active polymer is 1.92 mg/g. Under the same condition, its dynamic retention volume is greater than the amount of polymer retention.

pH-responsive amphiphilic macromolecular carrier for doxorubicin delivery

2016 ◽  
Vol 32 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Li Gu ◽  
Ning Wang ◽  
Leora M Nusblat ◽  
Rose Soskind ◽  
Charles M Roth ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Light Scattering ◽  
Magnetic Resonance ◽  
Critical Micelle Concentration ◽  
Cancer Cells ◽  
Degradation Products ◽  
Drug Loading ◽  
Ph Sensitive ◽  
Amphiphilic Macromolecules ◽  
Cytotoxicity Studies

In this work, pH-sensitive amphiphilic macromolecules are designed to possess good biocompatibility and drug loading while employing an acid-sensitive linkage to trigger drug release at tumor tissues. Specifically, two pH-sensitive amphiphilic macromolecules were synthesized with a hydrazone linkage between the hydrophobic and hydrophilic segments. The chemical structure, molecular weight, critical micelle concentration, micelle size, and pH-triggered cleavage of the amphiphilic macromolecules were characterized via matrix-assisted laser desorption/ionization time-of-flight, nuclear magnetic resonance, and dynamic light scattering techniques. Drug loading and release as well as cytotoxicity studies were performed using doxorubicin. Hydrodynamic diameters of the micelles formed with pH-sensitive amphiphilic macromolecules were within an optimal range for cellular uptake. The critical micelle concentration values were 10–8–10–6 M, indicating micellar stability upon dilution. The degradation products of the amphiphilic macromolecules after acidic incubation were identified using mass spectrometry, nuclear magnetic resonance, and dynamic light scattering methods. A pH-dependent release profile of the doxorubicin-encapsulated amphiphilic macromolecules was observed. Cytotoxicity studies against two cancer cell lines, MDA-MB-231 human breast cancer cells and A549 lung cancer cells, showed that doxorubicin encapsulated in pH-sensitive amphiphilic macromolecules decreased cell viability more efficiently than free doxorubicin, possibly due to the toxicity of the amphiphilic macromolecule degradation products. Resulting from enhanced release at acidic pH due to hydrolysis of the hydrazone linkage, pH-sensitive amphiphilic macromolecules also had improved efficacy toward cancer cells compared to other carriers (e.g. Pluronics®). These findings indicate that pH-sensitive amphiphilic macromolecules can potentially be applied as anticancer drug delivery vehicles to achieve controlled release and improved therapeutic effects.

Surface Active Phospholipids as Cartilage Lubricants

2008 ◽  
Author(s):  
Avi Schroeder ◽  
Gabi Verberne ◽  
Yulia Merkher ◽  
Dvorah Diminsky ◽  
Alice Maroudas ◽  
...  
Keyword(s):  
Synovial Fluid ◽  
Dynamic Friction ◽  
Low Friction ◽  
Natural Conditions ◽  
Multilamellar Vesicles ◽  
Synovial Joints ◽  
Dimyristoyl Phosphatidylcholine ◽  
Direct Association ◽  
Surface Active ◽  
Adhesive Forces

Efficient lubrication and extremely low friction are essential for proper functioning of synovial joints. Various joint dysfunctions were described in direct association with increased friction or adhesive forces. Surface-active phospholipids (SAPLs) are well known to reduce friction in synovial joints. This study demonstrates, using a novel human-sourced cartilage-on-cartilage setup, the potential of multilamellar vesicles (MLV) composed of the SAPL dimyristoyl phosphatidylcholine (DMPC) to act as effective lubricants, reducing static and dynamic friction-coefficients to levels of healthy synovial joints. Furthermore, MLV composed of DMPC, in sizes ranging from 0.8 to ∼3.5 μm, were found to be more effective lubricants than histidine buffer, saline, or synovial fluid. The ability to test new cartilage lubricants, simulating, to a great extent, natural conditions, using the setup presented herein is discussed.

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