Polyethylenimine-functionalized cationic barley β-glucan derivatives for macrophage RAW264.7 cell-targeted gene delivery systems

Cationic barley β-glucan derivatives (bGPEIs) with various polyethylenimine 2k (PEI2k) graft degrees were synthesized by periodate oxidation of backbone vicinal diols and reductive amination of PEI2k for gene delivery systems. bGPEIs could form positively charged (∼40 mV zeta-potential) and nano-sized (∼150 nm) spherical polyplexes. Cytotoxicity of bGPEIs was concentration and PEI graft degree-dependent. bGPEIs showed higher transfection efficiency and intracellular localization ability than PEI25k in RAW264.7 cell, especially in serum condition. High cellular uptake of bGPEI polyplexes at 4 °C in RAW264.7 cells suggested that bGPEIs would possess specific interaction ability with membrane receptors of RAW264.7 cells. In addition, bGPEIs could activate RAW264.7 cells, inducing the secretion of cytokine, tumor necrosis factor-α (TNF-α). Therefore, bGPEIs showed a potential for macrophage RAW264.7 cell-targeted gene delivery systems.