雷公藤甲素微乳凝胶的制备及体外透皮性能考察

目的：制备雷公藤甲素微乳凝胶并考察其理化性质及体外透皮扩散特性。方法：以混合乳化剂Tween80/Labrasol 1：4，助乳化剂无水乙醇，油相：油酸/Gemseal402：3，水相，泊洛沙姆407制备雷公藤甲素微乳凝胶。测定微乳的外观形态、粒径分布、pH、稳定性等理化性质。采用改良的Franz扩散池法，比较雷公藤甲素微乳凝胶和乳膏的经皮渗透特性。结果：制备的微乳澄清透明，呈现轮廓分明分布均匀的球形，平均粒径（27.8±0.3） nm，且PdI（0.2±0.004），稳定性等理化性质均较好。雷公藤甲素微乳凝胶和雷公藤甲素乳膏24h单位面积累积渗透量分别为（4.33±0.17）、（7.07±0.16） μg·cm^-2，2种剂型中雷公藤甲素的渗透行为均符合Higuchi方程，透皮速率分别为1.9871，0.9149 μg·cm^-2·h^-1。结论：雷公藤甲素微乳凝胶和乳膏均具有缓释释药效果。雷公藤甲素微乳凝胶显著提高了雷公藤甲素的经皮渗透量及透过速率，且较乳膏强，可为雷公藤甲素经皮给药制剂选择提供参考。

Preparation of Triptolide microemulsion-based gel and investigation of its in vitro percutaneous permeability

OBJECTIVE To prepare triptolide microemulsion and investigate its physical characteristics and its in vitro transdermal diffusion characteristics compare with creams.METHODS With tween-80/labrasol 1:4 as emulsifier, absolute alcohol as co-emulsifier, oleic acid/Gemseal404:6 as oil phase, mix queous phase to produce triptolide microemulsion. poloxamer 407 as gel matrix to produce Triptolide microemulsion-based gel. Morphology, particle size distribution, pH and stability were characterized. The transdermal permeation properties of microemulsion based gel compared with cream by modified Franze diffusion cell.RESULTS Microemulsion morphology was clear and transparent, nearly spherical under polarizing and transmission electron microscope, good stability, the particle size was(27.8±0.3) nm, and PdI (0.2±0.004) etc. The cumulative permeation amounts of triptolide microemulsion-based gel and cream were (4.33±0.17), (7.07±0.16) μg·cm^-2, respectively. Penetration behavior of triptolide microemulsion-based gel and cream conformed to Higuchi equation, transdermal rate were 1.9871, 0.9149 μg·cm^-2·h^-1, respectively.CONCLUSION Both triptolide microemulsion-based gel and cream have sustained release effect. Triptolide microemulsion-based gel afford a better percutaneous absorption. when compared to cream, which will supply evidence for the selection for the transdermal formulation of triptolide.