丹参酮Ⅱ_A固体脂质纳米粒的体外释药和大鼠肠吸收特性的研究

目的　考察丹参酮ⅡA固体脂质纳米粒 (TA SLN)的体外释药性质,研究肠道最佳吸收部位和吸收机制。方法　用透析法测定TA SLN体外释药速率,大鼠在体肠吸收实验考察肠道吸收行为。结果　药物的体外释放符合Weibull方程,具有缓释特性。在十二指肠,TA SLN与丹参酮ⅡA溶液的吸收率差异无显著性(P>0 05),在空肠、回肠和结肠段,TA SLN与丹参酮ⅡA溶液的吸收率差异均有显著性 (P<0 05)。丹参酮ⅡA溶液在各肠段的吸收率差异无显著性 (P>0 05),但TA SLN在结肠段的吸收率高于其它肠段,差异具有显著性(P<0 05)。在纳米粒浓度较高时,吸收趋向饱和;加入空白纳米粒,未增加纳米粒小肠吸收率;降低Na+浓度以及加入吸收促进剂(脱氧胆酸钠、吐温 80和十二烷基硫酸钠)和能量抑制剂(2, 4 二硝基苯酚)均使纳米粒小肠吸收率增加。结论　TA SLN在体外释放介质中可缓慢持续释药;结肠是TA SLN的最佳吸收部位。

Studies on drug release in vitro and rat intestinal absorption of tashinone ⅡA solid lipid nanoparticles

Aim To study release feature of tashinone Ⅱ A solid lipid nanoparticles(TA-SLN) in vitro,and clarify the differenc e in absorption of TA-SLN from varied intestinal segments and absorptive mechan ism in vivo.Methods Dialytic method was used to determine t ashinone Ⅱ A release rate of nanoparticles in vitro. An in situ rat perfusion method was used to investigate the intestinal absorption of TA-SLN.Resu lts Tashinone Ⅱ A release from TA-SLN in vitro fit the Weibull e quation well and had a property of sustained release. The absorption rate of tas hinone Ⅱ A solution from varied intestinal segments had no significant differe nce(P>0.05). However,compared with others segments, significantly high per centage of TA-SLN was absorbed in colon(P<0.05). The absorption of tashino ne Ⅱ A tended to be saturated with the high concentration of TA-SLN. It did n ot increase significantly when blank nanoparticles were added to the perfusion s olution(P>0.05). With the decrease of Na+ or existence of deoxycholate, T ween 80,SLS or DNP in the perfusion solution, the absorption rate increased rem arkably(P<0.05). Conclusion TA-SLN could sustain to relea se drug. The colon was the most potentest site of TA-SLN absorption in intestin al tract.