Characterization of the radical product formed from the reaction of nitric oxide with the spin trap 3,5-dibromo-4-nitrosobenzene sulfonate.
Previously, 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) has been used in combination with electron paramagnetic resonance (EPR) spectrometry to trap nitric oxide (NO(*)). The reaction between DBNBS and NO(*) yields a radical product which gives rise to an EPR signal consisting of three lines with an A(N) = 0.96 mT, but the structure of this product is unknown. A two-stage high-performance liquid chromatography fractionation was performed to isolate the radical product from the other components in the DBNBS/NO(*) reaction mixture. The fractions containing the radical product were identified by the presence of the three-line EPR signal, and then these fractions were analyzed by negative ion fast atom bombardment-mass spectrometry (FAB-MS). Collectively, the FAB-MS data suggested that the radical product is the monosodium electrostatic complex with the dianion, bis(2,6-dibromo-4-sulfophenyl) nitroxyl. Analysis of the Gaussian and Lorentzian linewidths of the EPR signal suggested that bis(2,6-dibromo-4-sulfophenyl) nitroxyl molecules may group together to form micelles. Further studies also indicated that significant amounts of nitrogen and nitrate were produced during the reaction between DBNBS and NO(*). A reaction scheme consistent with these results is presented.
Davies
C A
CA
Bone & Joint Research Unit, St Bartholomew's and the Royal London School of Medicine and Dentistry, Charterhouse Square, United Kingdom.
Nielsen
B R
BR
Timmins
G
G
Hamilton
L
L
Brooker
A
A
Guo
R
R
Symons
M C
MC
Winyard
P G
PG
D001557:Benzenesulfonates / Q000737:chemistry / Q000378:metabolism*; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D004578:Electron Spin Resonance Spectroscopy; D019075:Electrophoresis, Capillary; D005609:Free Radicals / Q000737:chemistry / Q000378:metabolism*; D013058:Mass Spectrometry; D008958:Models, Molecular; D008968:Molecular Conformation; D009566:Nitrates / Q000378:metabolism; D009569:Nitric Oxide / Q000737:chemistry / Q000378:metabolism*; D009573:Nitrites / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D009603:Nitroso Compounds / Q000737:chemistry / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D013113:Spin Labels
D001557:Benzenesulfonates; D005609:Free Radicals; D009566:Nitrates; D009573:Nitrites; D009603:Nitroso Compounds; D013113:Spin Labels; D009569:Nitric Oxide; C048757:3,5-dibromo-4-nitrosobenzenesulfonate; D009584:Nitrogen; D010100:Oxygen