Purity of different preparations of sodium 3,5-dibromo-4-nitrosobenzenesulphonate and their applicability for EPR spin trapping.

During the preparation of sodium 3,5-dibromo-4-nitrosobenzenesulphonate (DBNBS) of high purity for electron paramagnetic resonance (EPR) spin-trapping purposes, it was found that the material synthesised as part of the present study differed significantly from some commercially available samples of DBNBS. A thorough chemical characterisation of the contents of the various samples led to the conclusion that the preparations synthesised in the present study, as well as one of four commercially available samples, contained essentially pure DBNBS and had efficient spin-trapping activity. In contrast, the remaining three commercially available samples contained almost exclusively sodium 3,5-dibromo-4-nitrobenzenesulphonate, i.

Reaction of the spin trap 3,5-dibromo-4-nitrosobenzene sulfonate with human biofluids.

Using the spin trap 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS), an oxidant was previously detected in the plasma of patients with renal failure and the synovial tissue of rheumatoid arthritis patients. This oxidant has been shown to react with DBNBS to give a 3-line electron paramagnetic resonance (EPR) spectrum, previously assigned to the DBNBS radical cation (DBNBS*(+). However, confusion has arisen as to whether this paramagnetic species is indeed DBNBS*(+) or, rather, the DBNBS sulfite radical adduct (DBNBS-SO(3)*(-)).