Background: Glycolysis is not completely or predictably inhibited by the glucose preservative currently in use, with glucose values falling by as much as 0.5 mmol/L during a 2-4-h period after sample collection. Immediate centrifugation of all samples is also impractical and therefore misdiagnosis of disease can occur, especially if more emphasis is being placed on fasting glucose for the diagnosis of diabetes.
Methods: Glycolysis at room temperature was evaluated over time using glyceraldehyde alone as well as in conjunction with standard antiglycolytic agents.
Results: Glyceraldehyde alone does not inhibit glycolysis completely. The combination of 11 mmol/L glyceraldehyde, 119 mmol/L sodium fluoride and 21.7 mmol/L potassium oxalate gave the best antiglycolytic results. The glucose values measured in samples stored at room temperature for 48 h was no different from those measured in samples centrifuged immediately after venepuncture and this is clinically superior to conventionally used sodium fluoride and potassium oxalate.
Conclusion: Plasma glucose concentrations obtained from blood collected into tubes containing glyceraldehyde, sodium fluoride and potassium oxalate will more closely reflect those of the patient at venepuncture.