Fig. 6.
Time courses of nitrite-induced oxidation of Hb A0 under varied conditions. Solutions containing 30 μM Hb were rapidly mixed with 200-fold excess nitrite in 0.05 M Tris buffer at pH 7.4 in a stopped-flow instrument at room temperature. The spectral changes were monitored by a photodiode array detector over time. The absorbance changes at 577 nm plotted versus time are shown for reaction of stripped Hb A0 in air-equilibrated buffer (open circles); in O2 saturated buffer (open triangles); and in the presence of IHP in air-equilibrated buffer (closed circles).