Please use this identifier to cite or link to this item:
Title: Insulin encapsulation in reinforced alginate microspheres prepared by internal gelation
Authors: Silva, Catarina M. 
Ribeiro, António J. 
Ferreira, Domingos 
Veiga, Francisco 
Keywords: Alginate microspheres; Chitosan; Insulin release; Internal gelation; Anionic polyelectrolytes
Issue Date: 2006
Citation: European Journal of Pharmaceutical Sciences. 29:2 (2006) 148-159
Abstract: Insulin-loaded alginate microspheres prepared by emulsification/internal gelation were reinforced by blending with polyanionic additive polymers and/or chitosan-coating in order to increase the protection of insulin at simulated gastric pH and obtain a sustained release at simulated intestinal pH. Polyanionic additive polymers blended with alginate were cellulose acetate phtalate (CAP), Eudragit® L100 (EL100), sodium carboxymethylcellulose (CMC), polyphosphate (PP), dextran sulfate (DS) and cellulose sulfate (CS). Chitosan-coating was applied by using a one-stage procedure. The influence of additive polymers and chitosan-coating on the size distribution of microspheres, encapsulation efficiency and release profile of insulin in simulated gastrointestinal pH conditions was studied. The mean diameter of blended microspheres ranged from 65 to 106 [mu]m and encapsulation efficiency of insulin varied from 14 to 100%, reaching a maximum value when CS and DS were incorporated in the alginate matrix. Insulin release, at pH 1.2, was almost prevented by the incorporation of PP, DS and CS. When uncoated microspheres were transferred to pH 6.8, a fast dissolution occurred, independently of the additive polymer blended with alginate, and insulin was completely released. Increasing the additive polymer concentration in the alginate matrix and/or chitosan-coating the blended alginate microspheres did not promote a sustained release of insulin from microspheres at pH 6.8.
DOI: 10.1016/j.ejps.2006.06.008
Rights: openAccess
Appears in Collections:FFUC- Artigos em Revistas Internacionais

Files in This Item:
File Description SizeFormat
filef9ca2826cbcd4edc86107fdf2e94a24f.pdf927.57 kBAdobe PDFView/Open
Show full item record


checked on Aug 2, 2022

Page view(s) 50

checked on Aug 2, 2022

Download(s) 20

checked on Aug 2, 2022

Google ScholarTM




Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.