Enhanced photoinduced electron transfer between zinc phthalocyanine entrapped membrane and methyl viologen immobilized virus

COLL 449

Pascaline Ngweniform and Chuanbin Mao, cbmao@ou.edu. Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Room 208, Norman, OK 73019
Zinc phthalocyanine (ZnPc) was entrapped in the bilayer membrane of cationic liposomes. Methyl viologen (MV2+) was immobilized on a genetically engineered, negatively charged, rod-like virus. Electrostatic interaction occurred between the MV2+-immobilized virus and ZnPc-entrapped liposome, resulting in the formation of a self-assembled virus-membrane complex with ZnPc embedded in the lipid bilayer. Steady state fluorescence and transient absorption spectroscopic studies indicate that electron transfer occurred between the membrane-trapped ZnPc and MV2+ immobilized on the virus, with the negatively charged virus serving as an electron relay. The presence of the virus also enhanced charge separation, leading to the formation of the oxidized ZnPc+•and the reduced methyl viologen radical (MV+•). In the absence of the virus, no electron transfer occurred due to the electrostatic repulsion between the cationic liposome and the MV2+. Our results suggest that the virus-membrane complex can serve as a novel media for solar energy conversion.