Colorimetric Estimation of Phosphorus

Abstract

To determine the rate of colour formation and the optimum time for taking readings in the Fiske and Subbarow method of estimating phosphorus micro -chemically, we have used a simple type of photoelectric colorimeter (to be described in detail elsewhere) which allows the chemical reaction to be followed continuously until a state of equilibrium is reached. The method has been developed for the purpose of obtaining more accurate figures for the phosphorus content of the whole blood and its separate fractions (plasma, serum and red cells) than those hitherto obtained by other (visual) methods.