Shin S C, Cho C W, Choi H K
College of Pharmacy, Chonnam National University, Kwangju, Korea.
Drug Dev Ind Pharm. 1999 Mar;25(3):273-8. doi: 10.1081/ddc-100102171.
Topical formulations of piroxicam were prepared using poloxamer 407 or poloxamer 188 by a cold method, and the permeation characteristics of piroxicam were evaluated. The permeation rate of piroxicam across the synthetic cellulose membrane and the rat skin decreased as the concentration of poloxamer increased. Though poloxamer gel exhibits reversed thermal behavior, the permeation rate of piroxicam increased with increasing temperature, indicating that the diffusional pathway of piroxicam is a water channel within the gel formulation. The pH of the gel did not affect the permeation rate of piroxicam significantly. As the concentration of piroxicam in the gel formulation increased, the permeation rate of piroxicam increased up to 1% and reached a plateau above 1%. Among various enhancers tested, polyoxyethylene-2-oleyl ether showed the highest enhancing effect, with an enhancement ratio of 2.84. Based on experimental results, the permeation rate of piroxicam can be controlled by changing the poloxamer concentration or drug concentration and by the addition of an appropriate enhancer.
采用冷法用泊洛沙姆407或泊洛沙姆188制备吡罗昔康的外用制剂，并对吡罗昔康的渗透特性进行评价。随着泊洛沙姆浓度的增加，吡罗昔康透过合成纤维素膜和大鼠皮肤的渗透率降低。虽然泊洛沙姆凝胶表现出相反的热行为，但吡罗昔康的渗透率随温度升高而增加，这表明吡罗昔康的扩散途径是凝胶制剂内的水通道。凝胶的pH值对吡罗昔康的渗透率没有显著影响。随着凝胶制剂中吡罗昔康浓度的增加，吡罗昔康的渗透率在浓度达到1%之前增加，在1%以上达到平稳状态。在测试的各种促渗剂中，聚氧乙烯-2-油基醚显示出最高的促渗效果，增强比为2.84。基于实验结果，可通过改变泊洛沙姆浓度或药物浓度以及添加合适的促渗剂来控制吡罗昔康的渗透率。
