论文部分内容阅读
目的:研究pH值对吡罗昔康理化性质及经皮渗透性能的影响,为其经皮给药制剂的研究提供实验依据。方法:用HPLC法测定药物在水、不同pH缓冲液(PBS)中的溶解度;采用双波长分光光度法测定药物的解离常数(pKa);摇瓶法测定药物的表观油水分配系数(logP);利用透皮扩散池以稳态渗透速率常数(Js)和通透系数(Ps)为评价指标研究药物的透皮效果。结果:吡罗昔康的pKa为6.33。32℃时,吡罗昔康在pH 7.4的缓冲液中logP为0.17,且溶解度和Js均达到最大,分别为(420.445)μg.mL-1和(64.612±0.011)μg.cm-2.h-1;Ps为(0.154±0.014)cm.h-1。结论:调节药物pH值,使药物维持较高的溶解度和分子型药物比例,可望获得理想的皮肤通透性。
Objective: To study the effect of pH on the physiochemical properties and transdermal permeation of piroxicam, and to provide experimental basis for the study of transdermal drug delivery. Methods: The solubility of the drug in water and different pH buffers (PBS) was determined by HPLC. The dissociation constant (pKa) of the drug was determined by dual-wavelength spectrophotometry. The apparent oil-water partition coefficient (logP ); Transdermal diffusion cells were used to evaluate the transdermal effect of drug through steady-state infiltration rate constant (Js) and permeability coefficient (Ps). Results: When the pKa of piroxicam was 6.33.32 ℃, the logP of piroxicam in pH 7.4 buffer was 0.17, and the solubility and Js reached the maximum, which were (420.445) μg.mL-1 and (64.612 ± 0.011) μg.cm-2.h-1; Ps was (0.154 ± 0.014) cm.h-1. Conclusion: Adjusting the pH value of the drug can make the drug maintain the high solubility and the ratio of the molecular type drug, which is expected to achieve the desired skin permeability.