The determination of ethanol in whole blood by differential pH measurements

The application of a new technique based on the differential measurement of pH between two solutions to determine ethanol concentration in whole blood is reported. The ethanol is determined by measuring the change in pH following its enzymatic oxidation to acetaldehyde. The procedure correlates with the head space gas chromatographic method in the 0-108 mmol/l (0-5 g/l) ethanol whole blood concentration range according to the equation y = 1.344 + 1.013x (r = 0.997).