OBJECTIVE:To study the effect of five penetration enhancers on the transdermal permeability of sodium phenytoin in vitro.METHODS:Experiments were carried on penetration experimental facility using modified Franz-type horizontal diffusion cell with 0.9% sodium chloride as receptor solution.The content of sodium phenytoin in the receptor solution was determined by HPLC,and its accumulative permeation amounts and steady permeation rate were computed as well.The permeability of sodium phenytoin across the excised rat abdomen skin which has been pretreated with different penetration enhancers-ocenol(3%,5%,and 10%),menthol(3%,5%,and 8%),eucalyptus oil(0.5%,1%,and 3%),azone(1%,3%,and 5%) and N-methyl pyrolidone(3%,5%,and 8%) was observed.RESULTS:Five enhancers did improve the transdermal delivery of sodium phenytoin in a concentration dependent manner.At a respective optimum concentration,the permeation enhancing effects of enhancers in ascending order were 5% N-methyl pyrolidone

Objective Using rutin as the model drug to prepare floating alginate-chitosan microcapsule and investigate the feasibility of this pulsatile drug delivery system applied in Chinese materia medica.Methods By means of complex coacervation to prepare alginate-chitosan microcapsule and foaming agent to turn the microcapsule into gastric floating system and to investigate the release profile of the microcapsule in vitro and the influence of gas forming agent to the lag-time of the microcapsule.Results In vitro release,the microcapsule responded to the change of pH value and the release profile showed "S" profile,the lag-time increased from 3 h to 6 h as the quantity of gas forming agent with the dosage of foamer increased.Conclusion Floating alginate-chitosan microcapsule is suitable to be applied in pulsatile drug delivery system of Chinese materia medica with the desirable entrapment efficiency.