Determination of cytochromes in human liver contaminated with hemoglobin

A spectrophotometric method was developed to determine cytochromes in human liver mitochondria contaminated with hemoglobin. The influence of hemoglobin on the measurement was canceled by keeping hemoglobin in the carbon monoxide bound form throughout determination. Mitochondria were solubilized by 2% sodium cholate, and cytochromes were reduced enzymatically with glutamate and succinate as substrates to the maximal extent. The amount of cytochromes determined spectrophotometrically was linearly correlated with mitochondrial protein at least up to the extent of 8 mg/ml.