Stability of Insulin on Polycaprolactone Nanoparticles as a Function of Surface Properties
Nader I. Namazi *
Department of Pharmaceutics and Pharmaceutical Technology, College of Pharmacy, Taibah University, Al Madinah Al Munawarah 30001, Saudi Arabia.
*Author to whom correspondence should be addressed.
Abstract
The purpose of this research was to formulate insulin-loaded polycaprolactone (PCL) nanoparticles and evaluate structural stability of the protein using fluorescence spectroscopy. The size and morphology of the nanoparticles were characterized using dynamic light scattering (DLS) and scanning electron microscopy (SEM). Fluorescence emission data revealed that insulin is most stable with multilayer adsorption at pH close to its isoelectric point (IEP). The obtained particle size ranged from 130-140 nm+22 (SD). The loading amount of insulin onto the PCL nanoparticles was low at pH 7.4 and relatively high at pH 5.3. The adsorption phenomenon of protein onto hydrophobic nanoparticles provides a promising noninvasive carrier system for insulin.
Keywords: Protein adsorption, Insulin, PCL nanoparticles, Fluorescence spectra, dynamic light scattering