Excited-State Dynamics of NADH and 1-N-Propyl-1,4Dihydronicotinamide

Abstract

Time-resolved emission and transient absorption studies on the disodium salt of NADH and a simple analog, 1-N-propyl-1,4-dihydronicotinamide (NPNH) are reported. A broad, unstructured absorption spectrum similar to that of the solvated electron was obsd. after excitation of both NADH and NPNH. Fluorescence kinetics of NADH at room temp. showed a fast decaying emission component on the blue edge of the spectrum. The fluorescence lifetimes (ϕ) of NADH and NPNH in various solvents are given; ϕ is longer in D2O and EtOH than in H2O. Apparently, different conformations of NADH and NPNH contribute to this longer-lived fluorescence. [on SciFinder(R)]