Effect of functionalization of polymeric nanoparticles incorporated with whole attenuated rabies virus antigen on sustained release and efficacy

Nanovaccines introduced a new dimension to prevent or cure diseases in an efficient and sustained manner. Various polymers have been used
for the drug delivery to increase the therapeutic value with minimal side effects. Thus the present study incorporates both nanotechnology and
polymers for the drug delivery. Poly(D,L-lactic-co-glycolic acid)-b-poly(ethylene glycol) was incorporated with the rabies whole attenuated viral
antigen using double emulsion (W/O/W) method and characterized by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy
(AFM). Chitosan-PEG nanoparticles incorporated with the rabies whole attenuated virus antigen (CS-PEG NP-RVAg.) were prepared using Ionic
Gelation method. The CS-PEG NP-RV Ag. was surface modified with biocompatible polymers such as Acacia, Bovine Serum Albumin (BSA),
Casein, Ovalbumin and Starch by Ionic Gelation method. The morphology was confirmed by SEM and Transmission Electron Microscopy (TEM).
The surface modification was confirmed by Fourier Transform Infrared Spectroscopy (FTIR), Zeta potential. The size distribution of CS-PEG-RV
Ag. and surface modified CS-PEG-RV Ag. by respective biocompatible polymers was assessed by Zetasizer. Release profile of both stabilized
nanoparticles was carried out by modified centrifugal ultrafiltration method which showed the sustained release pattern of the Rabies Ag. Immune
stimulation under in-vitro condition was studied using rosette assay and phagocytosis assay. In-vitro toxicity using human blood and genotoxicity
using human blood DNA was also studied to assess the toxicity of the nanoformulations. The results of these studies infer that PLGA-b-PEG
nanoparticles, CS-PEG and surface modified CS-PEG nanoparticles may be an efficient nanocarrier for the RV Ag. to elicit immune response
sustainably with negligible toxic effect to the human system.