Bicarbonate Plays a Critical Role in the Generation of Cytotoxicity during SIN-1 Decomposition in Culture Medium
Figure 4
Chemical properties of decomposed SIN-1 in bicarbonate. (a) DHR-oxidizing activity. Serially diluted SIN-1 in 10 mM NaHCO3 was decomposed for 0, 4, and 24 h, neutralized with PBS, and incubated with DHR (final concentration 10 M) for 2 h. RD concentrations were calculated from a standard curve prepared from serially diluted RD. (b) N-nitrosating activity. Samples prepared as in (a) were mixed with DAN (final concentration 15 M) for 2 h, and the fluorescence intensity was measured. (c) Levels of and in each sample. The concentrations of SIN-1 in (a) and (b) represent the final concentrations in each assay. The concentrations of / in (c) indicate their concentrations in the original SIN-1-decomposed NaHCO3 solutions. All the values shown are means ± intra-assay deviations, expressed as SD, from three wells in a representative experiment.
