Adsorption and Hæmoglobin

Abstract

ONE fundamental difficulty in the hypothesis that oxygen and carbon monoxide are “adsorbed” by hæmoglobin lies in the highly specific nature of the absorption spectrum of the compounds so formed. The change in colour of reduced blood, or of a dilute solution of reduced hæmoglobin, when shaken with air or oxygen, is very obvious to the naked eye, as also is the change when the oxygen is replaced by carbon monoxide. These colour changes can be used, either as in Haldane's method with direct vision, or as in Hartridge's by the spectroscope, for the exact quantitative measurement of the amount of gas taken up. Such remarkable, definite, and highly specific changes in the absorption spectra have no parallel, so far as I am aware, in any well-authenticated case of adsorption (unless the phenomena of electrolytic dissociation be classed as such), and must be explained by any theory, as of course they are by that of a specific chemical change in the nature of hæmoglobin by its combination with gas.