User talk:Dr kamal kachhawa

Samples Stored at Different Storage Conditions

a common problem in clinical laboratories is maintaining the stability of serum analytes during sample storage. Samples are usually stored in the door (4–8°C) of a refrigerator for short durations or in a deep freezer (−20°C) for longer time periods. Thus, the temperature at which the samples are stored constitutes an important preanalytical variable that may affect analysis results in the clinical biochemistry laboratory setting.

The following analytes were examined: • Metabolites: Na+, K+, urea, creatinine, uric acid, total calcium, phosphorus, direct bilirubin, and total bilirubin • Proteins: Total protein and albumin • Lipids: Total cholesterol and triglycerides • Enzymes: Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and amylase.

The sample tubes were left in an upright position for 30 min at room temperature followed by centrifugation at 3500 rpm for 10 min. Serum samples were examined for hemolysis and lipemia to prevent possible interference.

The serum aliquots were stored frozen at −20°C for either 7 (T7d), 15 (T15d), or 30 (T30d) days and then analyzed separately for stability.

The results of our study indicate that nearly all of the examined metabolites were stable even after 30 days of storage at −20°C.

All common clinical chemistry analytes examined, aside from serum amylase, showed adequate stability following up to 30 days storage at −20°C. These results indicate that deep freezing at −20°C could serve a useful tool for additional analyses at later time points as well as for research purposes, which require that samples be stored for longer periods until batch analysis can be conducted.

Refrence : Kachhawa K, Kachhawa P, Varma M, Behera R, Agrawal D, Kumar S. Study of the stability of various biochemical analytes in samples stored at different predefined storage conditions at an accredited laboratory of India. J Lab Physicians 2017;9:11-5.