Analysis of Preanalytical Variable – Stability of Common Biochemical Analytes under Different Storage Conditions and Temperatures

Abstract

Aim: To evaluate the stability of 11 common biochemical analytes in serum samples under different storage conditions and temperatures. Materials and Methods: 5ml of venous blood were collected from each volunteer into sterile clot activator tubes. The samples were allowed to clot for 30 minutes at room temperature and centrifuged at 2500 rpm for 10 minutes. Serum was separated as early as possible within two hours from sample collection and made into four aliquots and analysed using XL 640 biochemical autoanalyzer. The first aliquot analysed within two hours act as a baseline value. The remaining three aliquots were stored as follows: Room temperature (20-25 ° C) for four hours, refrigerated at 2–8° C for four hours and refrigerated at 2–8° C for 24 hours, respectively. Results: Baseline serum values of biochemical analytes analyzed within two hours were compared with those stored under different conditions. Samples stored at room temperature for four hours showed a significant change in the values of glucose, urea, creatinine, total bilirubin, albumin, total protein, AST, ALT and ALP. Refrigerated at 2–8° C for four hours caused significant changes in glucose, urea and albumin. Storage at 2–8° C for 24 hours led to significant change among the values of glucose, total bilirubin, and albumin. Other analytes were found to be stable across different conditions. Conclusion: The study revealed that certain serum analytes like glucose, urea, bilirubin, and albumin are particularly sensitive to storage time and temperature, emphasizing the need for prompt analysis— ideally within 2 hours of collection. In contrast, serum creatinine, total protein, AST, ALT and ALP were stable on refrigeration. Total cholesterol and triglycerides remained stable under all tested conditions. These findings help enhance the accuracy of diagnostic practices by identifying which analytes are more affected by improper storage. Clinical Significance: In the framework of patient-centered healthcare delivery, clinical laboratories play a pivotal role in ensuring accurate diagnosis and effective treatment. While technological advancements have enhanced laboratory processes, preanalytical errors—particularly those arising from improper sample collection, handling, and storage—remain a persistent challenge. Such errors can compromise test results, leading to reduced confidence in healthcare services and potentially harming the institution’s credibility. Timely identification and correction of these errors are essential to safeguard the accuracy and reliability of laboratory data. Fostering effective interdepartmental collaboration is crucial to minimize preanalytical issues, thereby enhancing clinical decision-making and ultimately improving patient outcomes.