用在体皮肤微透析法研究黄芩苷凝胶经大鼠皮肤吸收的局部药动学

目的建立大鼠在体皮肤微透析技术,研究黄芩苷凝胶经皮吸收局部药动学。方法采用HPLC-MS/MS联用技术测定大鼠皮肤微透析液中黄芩苷的浓度。SD大鼠在麻醉状态下做皮肤微透析预处理,然后将黄芩苷凝胶涂于探针所在皮肤表面,收集皮肤微透析液样品进行黄芩苷浓度测定,绘制黄芩苷浓度-时间曲线,计算经皮吸收局部药动学参数。结果用于定量分析的离子对为m/z 447.3→271.2,黄芩苷在检测浓度范围内线性关系良好,色谱的专属性、精密度等测定结果均符合生物样品测定要求。体内皮下探针对黄芩苷的回收率为（24.40±0.91）%,240 min内各取样点回收率保持稳定;黄芩苷经皮给药后8 h内微透析液中均可检测到黄芩苷的存在,且药物在皮肤组织内浓度持续升高,AUC0-t为（50.04±34.17）（mg·min）/L。结论在体皮肤微透析法可用于黄芩苷经皮吸收局部药动学研究。

Study on local pharmacokinetics of baicalin gel after transdermal administration in rats by skin microdialysis in vivo

Objective To develop a novel skin microdialysis technology in vivo,and to determine the pharmacokinetic of ba-icalin after transdermal administration in rats. Methods An HPLC-MS/MS method used for the determination of baicalin in skin mi-crodialysis samples was established ,SD rats were pretreated with skin microdialysis operation under anesthesia , and then the baicalin gel was applied to the skin surface of probe in vivo.The baicalin concentration of skin microdialysates was determined , the time curve of baicalin concentration was drawn and the topical pharmacokinetics parameters of percutaneous absorption was calculated. Results Baicalin was optimized at the transitions m/z 447.3→271.2.The linearity correlation was good and the assay exhibited good precision and accuracy.The subcutaneous probe recovery of baicalin in vivo was（24.40±0.91）%and was stable over the 240 min study peri-od.Baicalin could be detected in the microdialysis samples after transdermal administration , and its concentration continued to rise in 8 h.AUC0-t in skin tissue was（50.04±34.17） mg· min·L^-1. Conclusion The method of skin microdialysis in vivo could be used in the local pharmacokinetic research of baicalin.