Preparation of chitosan-based nanoparticles for delivery of low molecular weight heparin

The chitosan nanoparticles (CSNPs) loading with low molecular weight heparin (LMWH) was prepared by ionic gelatin process of chitosan (CS) and sodium tripolyphosphate (TPP) and the preparation process was optimized by a central composite design (CCD). Encapsulation efficiency (96.98%), loading efficiency (30.76%), average diameter (814 nm) and zeta potential (+0.86 mV) were achieved for the optimal nanoparticle (NP) formulation, and the release behavior of drug from CSNPs in vitro fitted Weibull kinetics model. The relative bioavailability of oral administration in rats of LMWH loaded CSNPs to LMWH solution was 517%. The results showed that CCD may well predict desired in vitro characterization of LMWH CSNPs, and CSNPs can significantly enhance the oral absorption of LMWH in rats.