Control of photoinduced electron transfer from zinc-porphyrin to methyl viologen by supramolecular formation between monoclonal antibody and zinc-porphyrin.

Photoinduced electron transfer from tetrakis(4-carboxy-phenyl porphyrin)-zinc complex (Zn-TCPP) to an acceptor molecule (methyl viologen; MV2+) has been found to be controlled by the complex formation of monoclonal antibody 03-1 for the porphyrin (TCPP) and Zn-TCPP. Although there are no ground-state interactions between Zn-TCPP and MV2+ for a 2:1 complex of antibody 03-1 and Zn-TCPP, the fluorescence of Zn-TCPP is quenched by the addition of MV2+. The Stern-Volmer plots and emission lifetime studies show that there is a long-range electron transfer through the antibody 03-1.