Effect of Collection Tube Type on Glucose Stability in Whole Blood

Precise measurement of plasma glucose is essential in evaluation of diabetes. In vitro decreases in glucose concentration due to glycolysis may lead to missed diabetes diagnoses in individuals who have glucose concentrations near the decision limit. We evaluated the effect of three routinely used collection tubes (sodium heparin, sodium citrate, and sodium fluoride) on the stability of glucose in whole blood samples. We found that initial glucose concentration was not significantly different among three tube types. Immediate glycolysis inhibition was not achieved in any tube type, and only sodium fluoride was efficient in inhibiting glycolysis in the settings of delayed sample processing.