Probing insulin's secondary structure after entrapment into alginate/chitosan nanoparticles

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Sarmento, B (Author) Other; Ferreira, DC (Author) FFUP; Jorgensen, L (Author) Other; van de Weert, M (Author) Other

Journal

Title: European Journal of Pharmaceutics and Biopharmaceutics

Vol. 65

Pages: 10-17

ISSN: 0939-6411

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 135 Citations

Scopus - 170 Citations

Scientific classification

FOS: Medical and Health sciences > Basic medicine

Other information

Authenticus ID: P-004-D3R

DOI: 10.1016/j.ejpb.2006.09.005

Abstract (EN): The aim of the present study was to probe the structural integrity of insulin after being entrapped into chitosan/alginate nanoparticles produced by ionotropic polyelectrolyte pre-gelation. By manipulating the alginate:chitosan mass ratio and the pH during nanoparticle production, desired nanoparticles with a mean size of 850 (+/- 88) nm and insulin association efficiency of 81 (+/- 2)% were obtained. Insulin secondary structure was assessed by Fourier transform infrared (FTIR) and circular dichroism (CD) after entrapment into nanoparticles and after release from the particles under gastrointestinal simulated conditions. FTIR second-derivative spectra and area-overlap compared to an insulin standard confirmed that no significant conformational changes of insulin occurred in terms of alpha-helix and beta-sheet content. Far-UV-CD spectra corroborated the preservation of insulin structure during the nanoparticle production procedure. The presented nanoparticulate system is a promising carrier for insulin oral delivery since it preserves insulin structure and therefore also, potentially, its bioactivity.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8