What is a common potential source of error in the hexokinase method?

The hexokinase method is commonly used for measuring glucose levels in blood samples. A key feature of this method is its reliance on the reaction of glucose with ATP to produce glucose-6-phosphate, which is then converted to lactate, generating NADPH. Hemolysis, or the rupture of red blood cells in the sample, can introduce errors in this process as it releases intracellular components, such as hemoglobin and other enzymes, into the plasma or serum. These released substances can interfere with the accuracy of the glucose measurement by affecting the reaction dynamics or by consuming reagents that are critical for the enzymatic activity.

For example, hemoglobin might participate in other reactions or modify the reagents, leading to overestimation or underestimation of glucose levels. Additionally, hemolysis can cause variations in the sample's glucose concentration, as the release of glucose from red blood cells can skew results. Therefore, hemolysis is a recognized source of interference that must be monitored and controlled to ensure accurate results in the hexokinase glucose assay.