Fig. 4. Coenzyme reduction.
a Schematic illustration of electron transfer from formic acid to FMN and Cyt c mediated by NPs. b UV–Vis absorption spectra of FMN, FMN + HCOOK, and FMN + HCOOK + Pt after reacting for 5 min. c The concentrations of FMN and O2 versus time in the presence of HCOOK and Pt. d Repeated reduction and oxidation of FMN by HCOOK + Pt and air, respectively. e UV–Vis absorption spectra of different sample solutions after reacting for 5 min. f Kinetic curves of UV–Vis absorbance over time at 550 nm during Cyt c reduction under different conditions. g Catalytic performances of NPs for electron transfer from formic acid to coenzymes. h Catalytic performances of NPs for electron transfer from NaBH4 to coenzymes. All experiments were conducted in PBS (50 mM, pH = 7.4). Error bars represent standard deviation from three independent measurements.