水飞蓟素－两亲性壳聚糖胶束的制备及其大鼠在体肠吸收

制备水飞蓟素-两亲性壳聚糖胶束 (SM-OGC), 以提高水飞蓟素口服生物利用度, 并研究其在大鼠小肠各部位的吸收情况。采用透析法制备SM-OGC, 测定载药胶束的粒径、zeta电位等理化参数；并以水飞蓟素混悬液为对照，运用大鼠在体单向灌流模型，考察SM-OGC的口服吸收。结果表明，SM-OGC平均粒径为 (162.4 ± 3.0) nm, zeta电位为 (+32.6 ± 0.98) mV，包封率为 (39.17 ± 0.98) % , 载药量达到 (28.15 ± 0.43) % 。SM-OGC在各个肠段吸收皆显著高于水飞蓟素混悬液对照组 (P < 0.05), 且十二指肠吸收最好，结肠、空肠和回肠吸收相近。OGC胶束对水飞蓟素在大鼠小肠的吸收有明显的促进作用。

Preparation of silymarin-loaded amphiphilic chitosan micelle and its in situ absorption in rat intestine

To improve the oral bioavailability of silymarin, the silymarin-loaded amphiphilic chitosan    micelles (SM-OGC) were prepared.  The absorption of SM-OGC in rat intestine was investigated.  SM-OGC was prepared by dialysis method.  The size and zeta potential of SM-OGC were investigated.  Compared to silymarin suspension, the absorption of SM-OGC was investigated using in situ single pass perfusion model.  The diameters and zeta potential SM-OGC were (162.4 ± 3.0) nm and (+32.6 ± 0.98) mV, respectively.  The  encapsulation efficiency was (39.17 ± 0.98) % and the drug loading of SM-OGC was (28.15 ± 0.43) %.  The absorption of SM-OGC at different segments of intestine was significantly higher than that of silymarin suspension (P < 0.05).  The apparent absorption rate (K_a) and effective permeation coefficient (P_eff) at the duodenum were the largest.  K_a and P_eff had no significant difference between jejunum, ileum and colon.  OGC micelles might significantly promote the absorption of silymarin in the intestine tract.