Pharmaceutical Research

, Volume 22, Issue 11, pp 1879–1886

Insulin Containing Nanocomplexes Formed by Self-Assembly from Biodegradable Amine-Modified Poly(Vinyl Alcohol)-Graft-Poly(l-Lactide): Bioavailability and Nasal Tolerability in Rats


  • Michael Simon
    • Department of Pharmaceutics and BiopharmacyPhilipps University
  • Matthias Wittmar
    • Department of Pharmaceutics and BiopharmacyPhilipps University
  • Thomas Kissel
    • Department of Pharmaceutics and BiopharmacyPhilipps University
    • Medical Clinic and Policlinic 3Justus-Liebig University Giessen
Research Paper

DOI: 10.1007/s11095-005-7676-z

Cite this article as:
Simon, M., Wittmar, M., Kissel, T. et al. Pharm Res (2005) 22: 1879. doi:10.1007/s11095-005-7676-z


The bioavailability and local tolerability of insulin containing nanocomplexes from amine-modified poly(vinyl alcohol)-graft-poly(l-lactide) were studied in rats. Histology of the nasal epithelium was studied to document integrity of the mucosa.


Nanocomplexes (NC) were prepared by spontaneous self-assembly of insulin and the water-soluble amphiphilic polymer. Changes in blood glucose and insulin blood concentration were monitored in anesthetized rats using a glucose meter and enzyme-linked immunosorbent assay, respectively. Histological sections of the nasal cavity were examined after H&E staining by light microscopy.


NC reduced blood glucose level in fasted healthy rats by 20% after 50–80 min and in streptozotocin induced diabetic rats by 30% within 75–95 min compared to basal levels. In both animal models significant concentrations of human insulin were detected, with relative bioavailabilities Frel of 2.8 up to 8.3%. The more hydrophobic, lactic acid grafted polyester were more effective at a threefold higher polymer concentration, increasing the relative bioavailability Frel of a 5 IU/kg dose from 2.8 to 5.7%. Histological examination of the nasal mucosa after 4 h showed no signs of toxicity at the site of nasal administration.


These results demonstrate that the NC significantly enhanced insulin absorption, suggesting that amphiphilic biodegradable comb-polymers offer a promising approach for nasal peptide delivery.

Key Words

bioavailability in ratsinsulinnanocomplexesnasal administrationnasal carriernasal histology

Copyright information

© Springer Science + Business Media, Inc. 2005