Auricularia auricular polysaccharide-low molecular weight chitosan polyelectrolyte complex nanoparticles: Preparation and characterization

Abstract

Novel polyelectrolyte complex nanoparticles (AAP/LCS NPs) were prepared in this study and these were produced by mixing negatively charged auricularia auricular polysaccharide (AAP) with positively charged low molecular weight chitosan (LCS) in an aqueous medium. The AAP was extracted and purified from auricularia auricular, and then characterized by micrOTOF-Q mass spectrometry, UV/Vis spectrophotometry, moisture analyzer and SEM. The yield, moisture, and total sugar content of the AAP were 4.5%, 6.2% and 90.12% (w/w), respectively. The AAP sample was water-soluble and exhibited white flocculence. The characteristics of AAP/LCS NPs, such as the particle size, zeta potential, morphology, FT-IR spectra, DSC were investigated. The results obtained revealed that the AAP/LCS NPs had a spherical shape with a diameter of 223 nm and a smooth surface, and the results of the FT-IR spectra and DSC investigations indicated that there was an electrostatic interaction between the two polyelectrolyte polymers. Bovine serum albumin (BSA, pI = 4.8) and bovine hemoglobin (BHb, pI = 6.8) were used as model drugs to investigate the loading and release features of the AAP/LCS NPs. The results obtained showed that the AAP/LCS NPs had a higher entrapment efficiency (92.6%) for BHb than for BSA (81.5%). The cumulative release of BSA and BHb from AAP/LCS NPs after 24 h in vitro was 95.4% and 91.9%, respectively. The in vitro release demonstrated that AAP/LCS NPs provided a sustained release matrix suitable for the delivery of protein drugs. These studies demonstrate that AAP/LCS NPs have a very promising potential as a delivery system for protein drugs.