Reis Catarina Pinto, Ribeiro António J, Houng Simone, Veiga Francisco, Neufeld Ronald J
Laboratory of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Rua do Norte, 3000-295 Coimbra, Portugal.
Eur J Pharm Sci. 2007 Apr;30(5):392-7. doi: 10.1016/j.ejps.2006.12.007. Epub 2007 Jan 13.
Insulin-loaded alginate-dextran nanospheres were prepared by nanoemulsion dispersion followed by triggered in situ gelation. Nanospheres were characterized for mean size and distribution by laser diffraction spectroscopy and for shape by transmission electron microscopy. Insulin encapsulation efficiency and in vitro release were determined by Bradford protein assay and bioactivity determined in vitro using a newly developed Western blot immunoassay and in vivo using Wistar diabetic rats. Nanospheres ranged from 267 nm to 2.76 microm in diameter and demonstrated a unimodal size distribution. Insulin encapsulation efficiency was 82.5%. Alginate-dextran particles suppressed insulin release in acidic media and promoted a sustained release at near neutral conditions. Nanoencapsulated insulin was bioactive, demonstrated through both in vivo and in vitro bioassays.
通过纳米乳液分散随后触发原位凝胶化制备了负载胰岛素的海藻酸盐-葡聚糖纳米球。通过激光衍射光谱法对纳米球的平均尺寸和分布进行表征，并通过透射电子显微镜对其形状进行表征。通过Bradford蛋白质测定法测定胰岛素包封效率和体外释放，并使用新开发的蛋白质印迹免疫测定法在体外以及使用Wistar糖尿病大鼠在体内测定生物活性。纳米球的直径范围为267纳米至2.76微米，并呈现单峰尺寸分布。胰岛素包封效率为82.5%。海藻酸盐-葡聚糖颗粒在酸性介质中抑制胰岛素释放，并在接近中性的条件下促进持续释放。通过体内和体外生物测定均证明纳米封装的胰岛素具有生物活性。
