One major problem encountered in transdermal drug delivery is the low permeability of drugs through the skin barrier. In the present study, we developed a surfactant-ethanolic liposomal system to improve the transderm...One major problem encountered in transdermal drug delivery is the low permeability of drugs through the skin barrier. In the present study, we developed a surfactant-ethanolic liposomal system to improve the transdermal delivery of docetaxel （DTX）, a model drug for high molecular weight and poorly water-soluble drugs. Surfactant-ethanolic liposomes （SEL） were composed of phospholipids, ethanol, sodium cholate, DTX and PBS which were prepared by thin film dispersion method. The developed formulations were characterized by determining the vesicle shape and surface morphology, size and size distribution, entrapment efficiency and drug loading capacity. The effects of the developed formulations on the permeation of DTX across rat skin in vitro were investigated using the modified Franz diffusion cell under both occlusive and non-occlusive application condi- tions. The DTX SELs with optimum composition （phospholipid-surfactant, 85：15, w/w） provided a significantly higher steadystate amount of flux and cumulative permeation, compared to the tranditional liposomes, surfactant liposomes and ethanolic liposomes. The optimal SELs exhibited stable vesicle size, morphology and drug loading capacity. Our results indicated that SELs were promising carriers to enhance the transdermal delivery of DTX.展开更多
Sevelamer Carbonate is a crossolinked polymeric amine, it is the active ingredient in Renvela Tablets. Sevelamer Carbonate is indicated for the control of hyperphosphatamiea in patients with end-stage renal disease. T...Sevelamer Carbonate is a crossolinked polymeric amine, it is the active ingredient in Renvela Tablets. Sevelamer Carbonate is indicated for the control of hyperphosphatamiea in patients with end-stage renal disease. The binding parameter constants of Sevelamer Carbonate were determined using the Langmuir approximation for the dosage form at pH 4.0 and 7.0 by Ion Chromatography. An Ion Chromatogrpahy method has been developed to estimate free phosphate in in-vitro phosphate binding study of Sevelamer Carbonate Tablets. The method is selective and capable of detecting phosphate in the presence of placebo matrix. The method has been validated with a lower limit of quantitation of 0.2 mM for Phosphate. A linear response function was established in the range of concentrations 0.2 - 30.0 mM (r > 0.99) for Phosphate. The intra and inter day precision values for Phosphate met the acceptance as per Food and Drug Administrations guidelines. Phosphate was stable in the set of stability studies viz. bench-top and autosampler. The developed method was applied to in-vitro phosphate binding studies of Sevelamer Carbonate Tablets.展开更多
基金The Key Direction Program of Chinese Academy of Sciences(Grant No.kjcx2-sw-h12-01)
文摘One major problem encountered in transdermal drug delivery is the low permeability of drugs through the skin barrier. In the present study, we developed a surfactant-ethanolic liposomal system to improve the transdermal delivery of docetaxel （DTX）, a model drug for high molecular weight and poorly water-soluble drugs. Surfactant-ethanolic liposomes （SEL） were composed of phospholipids, ethanol, sodium cholate, DTX and PBS which were prepared by thin film dispersion method. The developed formulations were characterized by determining the vesicle shape and surface morphology, size and size distribution, entrapment efficiency and drug loading capacity. The effects of the developed formulations on the permeation of DTX across rat skin in vitro were investigated using the modified Franz diffusion cell under both occlusive and non-occlusive application condi- tions. The DTX SELs with optimum composition （phospholipid-surfactant, 85：15, w/w） provided a significantly higher steadystate amount of flux and cumulative permeation, compared to the tranditional liposomes, surfactant liposomes and ethanolic liposomes. The optimal SELs exhibited stable vesicle size, morphology and drug loading capacity. Our results indicated that SELs were promising carriers to enhance the transdermal delivery of DTX.
文摘Sevelamer Carbonate is a crossolinked polymeric amine, it is the active ingredient in Renvela Tablets. Sevelamer Carbonate is indicated for the control of hyperphosphatamiea in patients with end-stage renal disease. The binding parameter constants of Sevelamer Carbonate were determined using the Langmuir approximation for the dosage form at pH 4.0 and 7.0 by Ion Chromatography. An Ion Chromatogrpahy method has been developed to estimate free phosphate in in-vitro phosphate binding study of Sevelamer Carbonate Tablets. The method is selective and capable of detecting phosphate in the presence of placebo matrix. The method has been validated with a lower limit of quantitation of 0.2 mM for Phosphate. A linear response function was established in the range of concentrations 0.2 - 30.0 mM (r > 0.99) for Phosphate. The intra and inter day precision values for Phosphate met the acceptance as per Food and Drug Administrations guidelines. Phosphate was stable in the set of stability studies viz. bench-top and autosampler. The developed method was applied to in-vitro phosphate binding studies of Sevelamer Carbonate Tablets.
