Department of Pharmaceutical Sciences, Mahatma Gandhi University, Cheruvandoor Campus, Ettumanoor 686 631, Kerala, India.
Eur J Med Chem. 2013 Feb;60:249-53. doi: 10.1016/j.ejmech.2012.12.011. Epub 2012 Dec 19.
Insulin-loaded microspheres composed of chitosan 3% (w/v), and loading 120 IU insulin were produced by emulsion cross-linking method. Cross-linking time was 5 h and glutaraldehyde 3.5% (v/v) was used as cross-linker. Swelling ratio studies were evaluated to predict release of insulin from chitosan microspheres. Bacitracin and sodium taurocholate were incorporated in the formulations as proteolytic enzyme inhibitor and absorption enhancer, respectively. In vitro insulin release studies were performed in phosphate buffer pH 7.4 and also in HCl pH 2 with and without trypsin. Activity of bacitracin was also evaluated. In vitro release showed a controlled profile up to 12 h and the formulation containing 0.15% (w/v) of bacitracin revealed a maximum biological activity of about 49.1 ± 4.1%. Mathematical modeling using Higuchi and Korsmeyer-Peppas suggested a non-Fickian diffusion as the mechanism of insulin release. Insulin-loaded chitosan microspheres for oral delivery showed to be an innovative and reliable delivery system to overcome conventional insulin therapy.
采用乳化交联法制备了载有 120IU 胰岛素的 3%（w/v）壳聚糖微球。交联时间为 5 小时，使用 3.5%（v/v）戊二醛作为交联剂。通过溶胀比研究评估了胰岛素从壳聚糖微球中的释放情况。杆菌肽和牛磺胆酸钠分别作为蛋白水解酶抑制剂和吸收增强剂加入到配方中。在 pH7.4 的磷酸盐缓冲液中和含有和不含胰蛋白酶的 pH2 的 HCl 中进行了体外胰岛素释放研究。还评估了杆菌肽的活性。体外释放显示出长达 12 小时的控制释放特征，含有 0.15%（w/v）杆菌肽的制剂显示出约 49.1±4.1%的最大生物学活性。使用 Higuchi 和 Korsmeyer-Peppas 的数学模型表明，胰岛素释放的机制是非菲克扩散。用于口服递送的胰岛素载壳聚糖微球是一种创新且可靠的递送系统，可克服传统的胰岛素治疗。
