A Modification of the Spectrophotometric Method for Determining Oxyhemoglobin Affinity

The role of hemoglobin as a carrier of oxygen in the blood was established in 1859 by Hoppe­ Seyler (12). Bert (3, 4), using whole blood, fur­ nished experimental data whereby an oxyhcmoglobin affinity curve could be plotted. In 1886, C. Bohr published data on purified hemoglobin for the second curve of oxyhemoglobin affinity (23). By 1903, Bohr had established that the oxyhemoglobin affinity curve was S-shaped for both whole blood and hemoglobin in solution. Since that time, various methods have been reported, or modifications thereof, to estimate oxyhemoglobin affinity (2, 14, 15, 16, 18, 19, 24, 25, 26, 27). The curve resulting from a plot of the degree of hemoglobin saturation as a function of ambient oxygen pressure is conventionally described in terms of the empirical equation derived by Hill ( 17 ),