In this work, guanidinylated polyethylenimine-conjugated chitosan (CS-PEI-G) was synthesized, and characterized for efficient gene delivery systems. Low molecular weight PEI (0.8 kDa) was conjugated to chitosan as a low cytotoxic template for introduc...
In this work, guanidinylated polyethylenimine-conjugated chitosan (CS-PEI-G) was synthesized, and characterized for efficient gene delivery systems. Low molecular weight PEI (0.8 kDa) was conjugated to chitosan as a low cytotoxic template for introducing the integrated bio-functionalities and guanidine groups, which are important components of cellular penetrating peptides. Synthesized CS-PEI-G could form positively charged and nano-sized complexes with pDNA. CS-PEI-G showed enhanced transfection efficiency in comparison with unmodified CSPEI, and high transfection efficiency comparable to or higher than PEI25k, due to guanidine moieties and the serum stability of chitosan backbone. Flow cytometry results suggest that the improved transfection efficiency of CS-PEIG may be not induced by cellular uptake of polyplexes but by other factors, such as the nuclear localization ability of guanidine moieties. These results showed that the simple strategy of introducing the guanidine groups of high density to chitosan via small PEI linkers could be effective for developing efficient gene delivery carriers.