Determination of Carbon Monoxide in Blood by Gas Chromatography

A method for the determination of CO content in blood is described. Carbon monoxide bound to hemoglobin is released by hemolysis and reaction with K3Fe(CN)6 in a closed system. The gases liberated are then swept onto a 5 A molecular sieve column where CO is separated from other blood gases. The CO, after catalytic reduction to methane, is detected by flame ionization. The method is rapid, specific, and sufficiently sensitive to permit analysis of 0.1-ml. samples of normal blood. The accuracy of the method, expressed as the coefficient of variation (S.D. x 100/mean), is 1.8% for normal human blood.