Effect of changes in storage conditions and temperature on routine biochemical analytes in serum assessed at periodic intervals

Abstract

Background: To observe the changes in common biochemical analytes namely glucose, urea, creatinine, total protein, albumin, total cholesterol & triglycerides when subjected to different temperature and storage conditions. Materials & Methods: This study was conducted in 100 randomly selected OPD patients. 5 ml of blood was collected in a clot activator plain tube without any anticoagulant. Blood was allowed to clot at room temperature for 30 minutes and serum was separated in different aliquots. Common biochemical parameters were performed immediately from these sera. Then the sera were divided and stored at room temperature as well as at 2 to 8 °C. After that all parameters were measured again at intervals of 6 and 24 hours. Results: Baseline values of biochemical parameters analyzed within 2 hours of blood collection was compared with the same samples stored at room temperature and at 2-8 °C. Data was analyzed and statistical significance was calculated. It showed that glucose was highly unstable when stored at room temperature and even when stored at 2-8 °C for 24 hours, while the stability of creatinine and total protein was also less. Other analytes were found stable. Conclusion: This study helped us to identify sensitive analytes that significantly vary when not stored properly. If samples are delayed to be analyzed, then it is essential to store them at defined temperature for analytes like glucose, creatinine and total protein.