Effect of repeated freeze-thaw cycles on routine plasma biochemical constituents in canine plasma

• Published in: Veterinary clinical pathology Vol. 35; no. 3; pp. 339 - 340
• Main Authors: Reynolds, B, Taillade, B, Medaille, C, Palenche, F, Trumel, C, Lefebvre, H.P
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.09.2006; Wiley-Blackwell
• Subjects: alanine transaminase; Alanine Transaminase - analysis; alkaline phosphatase; Alkaline Phosphatase - analysis; Animals; Aspartate Aminotransferases - analysis; aspartate transaminase; Beagle; Blood Chemical Analysis - methods; Blood Chemical Analysis - veterinary; blood glucose; Blood Glucose - analysis; blood plasma; Blood Preservation - methods; Blood Preservation - standards; Blood Preservation - veterinary; blood proteins; Blood Proteins - analysis; Blood Specimen Collection - methods; Blood Specimen Collection - veterinary; calcium; chlorides; Clinical chemistry; creatine kinase; Creatine Kinase - analysis; creatinine; Creatinine - analysis; dog; dogs; Dogs - blood; freeze-thaw cycles; Freezing; frozen storage; Life Sciences; Minerals - analysis; phosphates; plasma; Plasma - chemistry; Plasma - enzymology; potassium; preanalytical error; Reproducibility of Results; sample stability; sodium; storage quality; Temperature; Time Factors; urea; Urea - analysis
• ISSN: 0275-6382; 1939-165X
• DOI: 10.1111/j.1939-165X.2006.tb00144.x

Background: The effect of repeated freeze‐thaw cycles on plasma constituents has not been assessed in dogs, although such a procedure is not uncommon to use in routine laboratory practice. Objective: To assess the effect of freeze‐thaw cycles on routine plasma constituents in healthy dogs. Methods: Six healthy adult dogs were used. Blood was sampled and placed in heparinized tubes. After centrifugation, plasma was separated into 5 aliquots. One aliquot was considered as the reference aliquot and used immediately for the assay of all of the biochemical constituents. All of the other aliquots were stored at −20°C. Three aliquots underwent 1, 2, or 3 freeze‐thaw cycles during a 1‐ to 3‐day period. The last aliquot remained at −20°C throughout the study and was thawed on the third day. The following biochemical constituents were assayed: glucose, urea, creatinine, total proteins, sodium, potassium, chloride, calcium, phosphates, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), and alkaline phosphatase (ALP). Results: No clinically relevant change was observed between the different aliquots for all of the constituents. Conclusion: Repeated freeze‐thaw cycles do not cause changes in the biochemical constituents studied in canine plasma.