Efficacy of vinyl imidazole grafted cationized pullulan and dextran as gene delivery vectors: A comparative study

The present study deals with efficacy evaluation of two cationised polysaccharides - Pullulan PEI and Dextran PEI as gene delivery vector after grafting with vinyl imidazole. Chemical modifications of these polysaccharides were confirmed by FTIR and NMR. Nanoplex formed from dextran PEI imidazole (DPI) were of smaller size and possess greater positive charge as compared to that of pullulan PEI imidazole (PPI). MTT assay carried out in C6 and HeLa cell lines revealed that both PPI and DPI are cytocompatible and the percentage cell viability is higher for former. Though DPI and PPI derivatives showed similar cellular uptake, the cell morphology was maintained with later and this may due to the high molecular flexibility of pullulan that masks the cytotoxicity of PEI. Similarly transfection studies carried out with p53 plasmid also revealed that PPI derivatives promote more apoptosis in both C6 and HeLa cell lines as compared to that of DPI derivatives. Based on cytocompatibility and transfection efficiency, PPI was found to be a better gene delivery vector that can be further explored for in vivo applications.