In-Vitro Study of Cancer Cell Binding and Photothermal Inhibition Efficiency by Gold Nanoparticles-Capped Iron Oxide Nanospheres

Abstract

Different from the traditional cancer cell targeting through protein biomarkers, strong negative surface charges of cancer cells over normal cells derived from the dramatic excretion of lactate acid by cancer cells due to their glycolysis have been testified as an effective cancer cell binding strategy. In our previous work, polyethylenimine (PEI)-functionalized iron oxide nanoparticles (NPs) with strong positive surface charge and good photothermal property have been applied to kill cancer cells in vitro. Considering the obvious cytotoxicity of the first generation of positively charged nanotherapeutics, second generation of magnetic nanotherapeutics with tunable surface charges was designed and prepared by shield of positively charged surface areas by negatively charged gold nanoparticles (AU NPs). In addition to reducing the cytotoxicity of original NPs, the photothermal property of magnetic NP core was simultaneously enhanced. Herein, the correlation of the capping degree of the positive surface charge by AU NPs and the photothermal inhibition of cancer cells was investigated.