Authors : Reshma D C
DOI : 10.18231/j.ijcbr.2019.066
Volume : 6
Issue : 3
Year : 2019
Page No : 299-302
Ex vivo glycolysis is the main interference factor in glucose estimation. In the unpreserved blood
sample the glucose concentration decreases rapidly, because of glycolysis. Sodium fluoride, inhibits
enzyme Enolase of glycolysis pathway. The latest guidelines provided by American Association for
clinical chemistry (AACC) and American Diabetes Association (ADA) for laboratory analysis have
recommended the use of tubes containing citrate buffer as inhibitor of glycolysis. It inhibits hexokinase
and phosphofructokinase.
Aims: To determine the efficacy of citrate buffer tubes compared to Sodium fluoride tubes as inhibitor of
glycolysis in glucose estimation.
Materials and Methods: 110 blood samples collected for Glucose estimation were included in the study.
From 5ml of collected blood one ml each was added in pairs of sodium fluoride and citrate buffer tubes,
labelled as 0 and 2hrs respectively. Glucose estimation was done on ERBA CHEM 5 V2 Semi-automated
analyzer by Glucose oxidase -peroxidase (GOD-POD) kit method.
Results: The analyzed levels of glucose obtained in NaF and citrate buffer at 0hrs was 110.0736.72mg/dl
and 111.1036.95mg/dl and at 2hrs was 104.0036.20mg/dl and 105.9036.86mg/dl. Statistically
significant difference was observed between the glucose levels obtained from both the tubes. The difference
between mean values of glucose concentration at 0hr and 2hrs for sodium fluoride and citrate buffer tubes
was 6.073.06mg/dl and 5.202.43mg/dl respectively.
Conclusion: The study concludes that there were statistically significant higher levels of glucose in citrate
tubes compared to fluoride tubes, which can help to reduce the preanalytical errors in glucose estimation
due to glycolysis. There is a need for further studies with improved composition of citrate buffer and studies
to evaluate the clinical impact of difference in glucose levels of both tubes in diagnosing diabetes.
Keywords: Sodium fluoride, Citrate buffer, Glucose estimation, Glycolysis inhibitors.