Calcium-Alginate Nanoparticles for Nonviral Gene Delivery

Natural biopolymers are widely used in the field of drug and gene delivery. In this study, alginate nanoparticles were prepared using water-in-oil reverse microemulsion as a template followed by calcium crosslinking of guluronic acid units of alginate polymer. After collected by ultracentrifugation, alginate nanoparticles were analyzed by electron microscopy to obtain the size and morphology which were varied with the ratio of water, oil, and surfactant used. To explore the possibility of harnessing Ca-alginate nanoparticles as gene delivery carriers, GFP-encoding plasmids were encapsulated in these nanoparticles to investigate the degree of endocytosis by NIH 3T3 cells and ensuing transfection rate. Our results revealed that Ca-alginate nanoparticles with an average size around 80 nm in diameter are very efficient gene carriers, in comparison with widely-studied PEI/DNA complexes.