Journal
INTERNATIONAL JOURNAL OF PHARMACEUTICS
Volume 376, Issue 1-2, Pages 46-55Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.ijpharm.2009.04.014
Keywords
Oral delivery; Proteins and peptides; Polymeric self-assemblies; Nano-complexes; Enzymatic degradation
Categories
Funding
- Cunningham Trust
Ask authors/readers for more resources
Novel amphiphilic polyallylamine (PAA) were previously synthesised by randomly grafting palmitoyl pendant groups and subsequent quaternising with methyl iodide. The ability of these self-assembled polymers to spontaneously form nano-complexes with insulin in pH 7.4 Tris buffer was evaluated by transmittance study, hydrodynamic size and zeta potential measurements. The transmission electron microscopy images showed that non-quaternised polymer complexes appeared to form vesicular structures at low polymer:insulin concentrations. However, at higher concentrations they formed solid dense nanoparticles. The presence of quaternary ammonium moieties resulted in insulin complexing on the surface of aggregates. All polymers exhibited high insulin complexation efficiency between 78 and 93%. Incubation with trypsin, alpha-chymotrypsin and pepsin demonstrated that most polymers were able to protect insulin against enzymatic degradation by trypsin and pepsin. Quaternised polymers appeared to have better protective effect against trypsinisation, possibly due to stronger electrostatic interaction with insulin. Interestingly, non-quaternised polymers significantly enhanced insulin degradation by alpha-chymotrypsin. All polymers were less cytotoxic than PAA, with the quaternised polymers exhibiting up to 15-fold improvement in the IC50 value. Based on these results, quaternised palmitoyl graft polyallylamine polymers showed promising potential as oral delivery systems for insulin. (C) 2009 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available