Two-photon-excited fluorescence and two-photon spectrofluoroelectrochemistry of riboflavin

A two-photon spectrofluoroelectrochemical system has been established for the first time through combining two-photon-excited fluorescence and electrochemical methods. Ti: Sapphire Laser is used to induce two-photon-excited fluorescence in the researches. The results indicate that, when excited by 740 nm laser photons, riboflavin emits strong two-photon fluorescence, its two-photon absorption cross section is 35 GM and the quantum yield is 0.26. The formal potential of the electrochemical reaction is −0.56 V and the number of electrons transferred is 1.8.