Department of Medical Life Science, Faculty of Medical Bioscience, Kyushu University of Health and Welfare, Nobeoka, Japan.
Department of Clinical Laboratory Sciences, Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube 755-8505, Japan.
Clin Chem Lab Med. 2019 Aug 27;57(9):1388-1396. doi: 10.1515/cclm-2018-1109.
Background Many reports address the stability of biochemical analytes in serum. However, studies covering a wide range of storage temperatures are unavailable. Using equipment enabling precise temperature control, we investigated the effect of six different storage temperatures on serum analytes. Methods Serum specimens from seven healthy volunteers were obtained and divided into multiple aliquots for storage at -30, -20, -10, 0, 4, and 25 °C. On days 1, 3, 7, 14, 28 and 56, the aliquots stored at each temperature were relocated to a deep freezer maintained at -80 °C. On day 60, all aliquots were measured collectively for 13 major chemistry analytes. Results (1) At 25 °C, alanine aminotransferase (ALT), creatine kinase (CK), aspartate aminotransferase (AST) and total bilirubin (TBil) were very unstable especially on day 7 and later. (2) At ≤4 °C, alkaline phosphatase (ALP), γ-glutamyltransferase (GGT), amylase (AMY), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglyceride (TG), TBil and complement component-4 (C4) were generally stable and were very stable at 25 °C until day 14. (3) Between -20 and 4 °C, especially at -10 °C, test results of ALT, AST and lactate dehydrogenase (LDH) showed prominent decreases, but their stability was greatly improved at -30 °C. (4) In contrast, the value of complement component-3 (C3) increased at ≥- 20 °C. (5) At -30 °C, test results of all analytes were generally very stable except for ALT and CK, which showed noticeable reductions in activity after 14 days. Conclusions This is the first study to assess the stability of serum analytes at six graded temperatures simultaneously. Each analyte has a unique stability pattern for a range of temperatures.
背景 许多报告都涉及血清生化分析物的稳定性。然而，目前尚无涵盖广泛存储温度范围的研究。本研究使用能够精确控制温度的设备，研究了六种不同存储温度对血清分析物的影响。
方法 从 7 名健康志愿者中采集血清标本，分成多份，分别在-30、-20、-10、0、4 和 25°C 下储存。在第 1、3、7、14、28 和 56 天，将每种温度下储存的等分试样转移到保持在-80°C 的深冻库中。在第 60 天，对所有等分试样进行了 13 项主要化学分析物的集体测量。
结果 (1) 在 25°C 下，丙氨酸氨基转移酶(ALT)、肌酸激酶(CK)、天门冬氨酸氨基转移酶(AST)和总胆红素(TBil)特别不稳定，尤其是在第 7 天及以后。(2) 在≤4°C 下，碱性磷酸酶(ALP)、γ-谷氨酰转移酶(GGT)、淀粉酶(AMY)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)、TBil 和补体成分-4(C4)一般稳定，在 25°C 下非常稳定，直到第 14 天。(3) 在-20 到 4°C 之间，特别是在-10°C 时，ALT、AST 和乳酸脱氢酶(LDH)的检测结果明显下降，但在-30°C 下稳定性大大提高。(4) 相比之下，补体成分-3(C3)在≥-20°C 时增加。(5) 在-30°C 下，除 ALT 和 CK 外，所有分析物的检测结果均非常稳定，在第 14 天后其活性明显下降。
结论 这是第一项同时评估六种不同温度下血清分析物稳定性的研究。每种分析物在不同温度范围内都有独特的稳定性模式。
