thin layers of haemoglobin solution

Previous studies on simultaneous diffusion and chemical reaction in thin layers of haemoglobin solution have been mainly limited to theoretical calculations which have not as yet been submitted to detailed experimental verification. In the present work this gap has been filled by experiments on, and theoretical treatment of, displacement of oxygen by carbon monoxide from combination with haemoglobin when layers of the latter are exposed to gas mixtures of 1% CO in air or 1% CO in 02. Under these conditions the chemical reaction is essentially bimolecular with respect to CO and oxyhaemoglobin and is nearly irreversible over the early stages. This process was selected for study, because it can be followed by existing methods of observation of 3 to 6% oxyhaemoglobin solution in layers 50 to 100,/ thick, under which conditions diffusion and chemical reaction are of comparable importance. The appropriate differential equations have been solved numerically, allowance being made for (a) the diffusion of haemoglobin as well as the dissolved gases, (b) the small effect of the back reaction. Although the experimental results were somewhat scattered their average deviation from the theoretical calculations was less than 10% . Since the numerical values of all the parameters, used in the theoretical calculations, were based on independent experimental determinations, such concordance is certainly as good as could be expected and thus provides a satisfactory check of the validity of the theoretical treatment.