Spectrophotometric studies of the reaction of methaemoglobin with hydrogen peroxide. 1. The formation of methaemoglobin-hydrogen peroxide

Abstract

The unstable red substance formed when hydrogen peroxide is added to an acid methaemoglobin solution (Kobert, 1900) was shown by Keilin & Hartree (1935) and Haurowitz (1935) to be a welldefined compound apparently analogous to the azide, fluoride, cyanide and hydrosulphide compounds of methaemoglobin, with absorption bands at 545 and 589 mIA., and requiring for its formation 1 molecule of hydrogen peroxide for each iron atom of haematin. The compound is unstable, and in the subsequent reaction part of the methaemoglobin is recovered whilst the remainder is lost by oxidative degradation to unidentified products (Keilin & Hartree, 1935). We have shown that in the reaction between human haemoglobin and hydrogen peroxide in the

Biochemistry of Myoglobin, Changes Associated with Irradiating Meat and Meat Extracts with Gamma Rays

“…The formation of this shoulder was not accompanied by a shift of peak from 635 µ to between 620 and 610npuand the disappearance of the peak at 500 µ. The curve is similar to that presented for the hydrogen peroxide metmyoglobin (8). In the presence of 0.05% ascorbic acid the shoulder did not form even after 2.3 X 106 rep.…”

The Effect of Laser Power on Photothermoacoustic Imaging of Blood Containing Gold Nanoparticles and Deoxygenation using a Frequency-Domain Phased Array Probe: An In-vitro Assay

“…An unstable oxidation product of Na 2 S 2 O 4 is hydrogen peroxide which reacts with several heme pigments. If HbO 2 is reduced by Na 2 S 2 O 4 and then converted into carboxyhemoglobin, the absorption spectrum of the product shows a greater absorption in the red [46]. This may explain the reason for the higher PAR signal produced by absorption of 800 nm photons by S5 in figure 7.…”

“…Sodium dithionate is used to dissociate dioxygen from HbO 2 in erythrocytes by removing the external O 2 rather than diffusing into the RBCs [46]. The RBC color depends on the state of the hemoglobin: when combined with oxygen, the resulting oxyhemoglobin is scarlet, and when oxygen has been released the resulting deoxyhemoglobin is dark red, and can appear bluish through the vessel wall and skin.…”

The kinetics of deoxygenation of human haemoglobin

“…The HbO2 concentration, expressed as m-equiv./l. (mEq), that is m-moles of haem or combined oxygen/l., was calculated from measurements of E576M and a value for e.Eq of 15-4 (Dalziel & O'Brien, 1954; Lemberg & Legge, 1949).…”