溴吡斯的明新型纳米乳体外释放和大鼠在体胃肠吸收

In vitro release and gastrointestinal absorption of novel pyridostigmine bromide nanoemulsion

目的制备油包水型溴吡斯的明新型纳米乳(novel pyridostigmine bromide nanoemulsion,PPNE),研究其体外释放规律及各胃肠段吸收动力学特征。方法选用3种不同浓度pH 6.8、pH 7.4、pH 7.8的PBS以及pH 1.2的HCl作为释药介质,测定并绘制其体外释药曲线;并采用在体单向肠灌流实验模型,比较溴吡斯的明(pyridostigmine bromide,PB)和PPNE在胃肠道的吸收行为。结果在4种释放介质中,PB释放速率较快,而PPNE释放速率相对减缓;PPNE的吸收速率常数(K_a)和表观渗透系数(P_(app))较PB在十二指肠、空肠、回肠、结肠段中均增加。经t检验,PB和PPNE在4个肠段均有统计学意义(P<0.05)。结论 PPNE可提高药物的生物利用度,明显提高其药物在体肠段的吸收;体外释放中有良好的缓释效果。

Aim To prepare the novel pyridostigmine bromide nanoemusion（PPNE）and study its release in vitro, and to investigate the intestinal absorption. Methods Pyridostigmine bromide （PB）and PPNE were tested by HPLC in pH 1 .2 HCl,pH 6.8,pH 7.4,pH 7.8 PBS.Rat single pass intestinal perfusion method was employed to investigate the absorption mechanism of PB and PPNE.Results PB release rate was faster than PB in the four release media;the intes-tinal absorption rate constant（Ka ）and apparent perme-ability coefficient（Papp）of PPNE were increased in the duodenum,jejunum,ileum and colon segments.PB and PPNE had significant difference in the duodenum, jejunum,ileum and colon segments by t test （P 〈0.05）.Conclusions PPNE can improve the bioavail-ability of drugs,increase the drugs permeability,sig-nificantly improve the absorption of the drugs in the in-testinal segments. PPNE has obviously sustained effects.