蟾蜍毒素微乳的制备及体外透皮吸收考察

Preparation and in vitro Percutaneous Absorption Investigation of Bufotoxin Microemulsion

目的:制备蟾蜍毒素微乳并考察其理化性质及体外经皮给药特性。方法:通过溶解度试验和伪三元相图筛选蟾蜍毒素微乳处方,考察蟾蜍毒素微乳的外观形态、粒径分布、Zeta电位及稳定性,通过透皮扩散仪考察蟾蜍毒素微乳的体外透皮过程。采用RP-HPLC测定蟾蜍毒素含量,色谱条件为ZORBAX SB-C18色谱柱(4.6 mm×150 mm,5μm),流动相甲醇-水(70∶30),流速1.0 mL·min-1,柱温30℃,检测波长300 nm,进样量10μL。结果:优选的微乳处方为辛酸癸酸三甘油酯-聚氧乙烯氢化蓖麻油-二乙二醇单乙基醚-水(10.47%∶33.69%∶11.23%∶44.61%),载药量(1.36±0.12)%。制得的蟾蜍毒素微乳外观圆整,平均粒径(31.33±5.362)nm,多分散指数(0.103±0.025),Zeta电位-(30.85±3.25)mV。蟾蜍毒素微乳12 h的累积渗透量1 339.32μg·cm-2,皮肤滞留量1 895.36μg,分别是蟾蜍毒素水溶液的3.96,4.89倍。结论:蟾蜍毒素微乳稳定性较好,可显著促进蟾蜍毒素的透皮吸收。

Objective： To prepare bufotoxin microemulsion and investigate its physicochemical properties and in vitro penetration characteristics. Method： Bufotoxin microemulsion prescription was screened by solubility tests and pseudo-ternary phase diagrams; Morphology, particle size, Zeta potential and stability of microemulsion was investigated; In vitro transdermal process of bufotoxin microemulsion was investigated by transdermal diffusion instrument. The content of bufotoxin was determined by RP-HPLC, chromatographic conditions were as follows： ZORBAX SB-C18 column （4.6 mm × 150 mm, 5 μm） , mobile phase of methanol-water （7.0： 30） , flow rate 1.0 mL·min-1 ,column temperature 30 ℃, detection wavelength 300 nm, injection volume 10 μL. Result： Optimal microemulsion formulation consists of GTCC-Cremophor RH 40-Transcutol HP-water （ 10.47% ： 33.69% ： 11.23%： 44.61% ）, drug loading of （1.36 ±0.12）%. Appearance of bufotoxin microemulsion was round, average particle size, PDI and Zeta potential were （31.33 ± 5. 362） nm, （0. 103 ±0. 025） and- （30. 85 ± 3.25） mV, respectively. Cumulative amount and skin retention amount of bufotoxin microemulsion in 12 h were 1 339.32 μg ·cm-2 and 1 895.36 μg, which was 3.96 and 4.89 folds higher than that of bufotoxin saturated solution, respectively. Conclusion ： Bufotoxin microemulsion was stable, it could significantly promote transdermal absorption of bufotoxin.