Fig. 3.
Electron paramagnetic resonance (EPR) detection of NO formation from NDHP in the presence of XOR and different electron donors. The EPR spectra (X-band) of water-soluble complex NO-Fe(MGD)2 was recorded at room temperature. A total of 1 mL reactional buffer (PBS, pH 7.4) contained NDHP (1 mM), XOR (0.05 U/mL), and NADH (1 mM, a), xanthine (500 µM, b), or 2,3-dihydroxybenzaldehyde (DBA, 500 µM, c) as electron donors. The short-lived nitric oxide donor DEA NONOate was used as positive control (d). The parameters for the EPR device (MiniScope MS400, Magnettech) were 10 mW of microwave power, 0.6 mT of amplitude modulation, 100 kHz of modulation frequency, 12 s of sweep time, and 20 number of scans. Traces are representative from 3 to 4 independent experiments.