Takishima Junko, Onishi Hiraku, Machida Yoshiharu
Department of Drug Delivery Research, Hoshi University, Tokyo, Japan.
Biol Pharm Bull. 2002 Nov;25(11):1498-502. doi: 10.1248/bpb.25.1498.
Cephradine-containing ethylcellulose microparticles (MPC) were prepared by the solvent evaporation method. Chitosan-coated MPC (Chi-MPC) were prepared by doping MPC with viscous chitosan solution and subsequently drying. When fluorescein isothiocyanate (FITC)-labeled chitosan-coated ethylcellulose microparticles without drug were administered intraduodenally, they moved slowly in the intestine, that is, most of them were retained at the upper and middle parts of the small intestine for more than 8 h, which is considered due to mucoadhesive properties of coated chitosan. When MPC and Chi-MPC was incubated at 37 degrees C in the JP 14 second fluid, pH 6.8, both released the drug slowly with similar release rates. Cephradine solution and suspension, MPC and Chi-MPC were administered intraduodenally to investigate intestinal drug absorption. Only Chi-MPC suppressed the initial plasma level and maintained the plasma concentration for a long time up to 24 h, suggesting Chi-MPC would be useful for prolonged intestinal absorption of cephradine.
采用溶剂蒸发法制备了含头孢拉定的乙基纤维素微粒（MPC）。通过将MPC与粘性壳聚糖溶液掺杂并随后干燥来制备壳聚糖包衣的MPC（Chi-MPC）。当将不含药物的异硫氰酸荧光素（FITC）标记的壳聚糖包衣的乙基纤维素微粒经十二指肠给药时，它们在肠道中移动缓慢，也就是说，它们中的大多数在小肠的上部和中部保留超过8小时，这被认为是由于包衣壳聚糖的粘膜粘附特性。当MPC和Chi-MPC在37℃下于pH 6.8的JP 14第二液中孵育时，两者均以相似的释放速率缓慢释放药物。将头孢拉定溶液和混悬液、MPC和Chi-MPC经十二指肠给药以研究肠道药物吸收。只有Chi-MPC抑制了初始血浆水平并将血浆浓度长时间维持至24小时，这表明Chi-MPC对于延长头孢拉定的肠道吸收将是有用的。
