Preparation of chitosan nanoparticles containing Naja naja oxiana snake venom

Hydrophilic nanoparticles have received much attention for delivery of therapeutic peptides, proteins, and antigens. Chitosan (CS) is a biodegradable and nontoxic polysaccharide, as a carrier for drug delivery. The study purpose was to evaluate the influence of a number of factors on the encapsulation of Naja naja oxiana (Indian or speckled cobra) venom and loading capacity, as well as to investigate the physicochemical structure of nanoparticles. CS nanoparticles were produced based on the ionic gelation process of tripolyphosphate (TPP) and CS. All the preparations were estimated with diameter 120-150 nm and spherical shape using transmission electron microscopy. Fourier transform-infrared spectroscopy confirmed that tripolyphosphoric groups of TPP linked with ammonium groups of CS in the nanoparticles. Our results showed that CS can react with TPP to form stable cationic nanoparticles. Therefore, when chitosan concentration was increased to 1.5 mg/mL the aggregates with large diameter were formed. Optimum loading capacity and encapsulation efficiency of venom at a concentration of 500 microg/mL were achieved for low-molecular-weight (low-MW) CS at a concentration of 2 mg/mL and high-MW CS at a concentration of 3 mg/mL.

In this study a hydrophilic nanoparticle chitosan was investigated as a protein delivery system, and optimum conditions were established for future use of this technology.