目的 制备供口服给药的美洲大蠊提取物(CII-3)纳米粒,研究CII-3纳米粒的体外释放以及纳米粒对所包载的CII-3的体外保护作用。方法 采用复乳/溶媒蒸发法制备CII-3纳米粒,以人工胃肠液及p H 7.4的磷酸盐缓冲液(PBS)为释放介质,采用福林酚法测定CII-3纳米粒的体外释药特征,并对纳米粒的体外释药行为进行方程拟合,找到最佳释放模型;采用茚三酮显色法分别测定CII-3和CII-3纳米粒在p H 1.2人工胃液中不同时间点的氨基酸释放量,并对二者的降解速率进行对比,观察将CII-3包载入纳米粒后是否对CII-3有保护作用。结果 制得的CII-3纳米粒平均粒径为(109.9±0.6)nm,Zeta电位为(-37.5±3.5)m V。CII-3纳米粒前2 h在人工胃液中的累积释放率(Qt)为(22.63±1.17)%,此后在人工肠液中释放,60 h的Qt为(72.35±1.90)%,符合Higuchi释放模型,方程为Qt=8.287 2 t1/2+7.758 6。CII-3纳米粒在p H 7.4的PBS中10 d的Qt为(72.67±1.65)%,符合Weibull分布模型,方程为lnln[1/(1-Qt)]=0.403 7 ln(t-0.411 9)-1.713 3。CII-3在人工胃液中4 h基本全部降解,而包载入纳米粒后约70%CII-3在人工胃液中被降解。结论 CII-3纳米粒具有良好的缓释性,体外释放平稳。纳米粒中的CII-3在人工胃液中的稳定性提高。
Objective To prepare Periplaneta americana extract CII-3-1oaded nanoparticles for oral administration, and to investigate the in vitro release profile of CII-3-1oaded nanoparticles and the protection ofnanoparticles for CII-3 extract in vitro. Methods The in vitro release behavior of the CII-3-1oaded nanoparticles was carried out in the artificial gastric juice, artificial intestinal juice, and pH 7.4 PBS, and the fitting of different models was performed based on the accumulative drug release percentages observed by Folin-reagent method; The amino acid content of CII-3 and CII-3-1oaded nanoparticles at different time points in artificial gastric juice was determinated by ninhydrin colorimetry and degradation rates of the two drugs were compared. Results The mean size of the resulted nanoparticles was about (109.9 ± 0.6) nm and the Zeta potential was (-37.5 ± 3.5) mV; The accumulative release level of CII-3-1oaded nanoparticles Qt was (22.63 ± 1.17)% in the artificial gastric juice in the first 2 h, and then, in the artificial intestinal juice, the accumulative release level of ClI-3-1oaded nanoparticles over a period of 60 h was (72.35 -~ 1.90)%, which was in line with Higuchi model release equations, Qt = 8.287 2 t1/2 + 7.758 6. The accumulative release level ofCII-3-1oaded nanoparticles was (72.67 ±1.65)% over a period of 10 d, which was in line with Weibull equation, lnln[1/(1 -Qt)] = 0.403 7 in(t-0.411 9)-1.713 3; The CII-3 was completely degraded in 4 h in the artificial gastric juice, while about 70% of CII-3 contained in nanoparticles was degraded. Conclusion CII-3-1oaded nanoparticles have a satisfactory sustained in vitro release effect, and the stability of CII-3 contained in the nanoparticles is improved in the artificial gastric juice.