Abstract

This report aimed to determine the effects of different preservatives used to maintain the integrity of urine samples for a 24-hour urine collection on urinary iodine measurement by the Sandell–Kolthoff method in vitro. The selected preservatives were hydrochloric acid, acetic acid, boric acid, sodium carbonate, sodium fluoride, thymol with isopropanol, sodium chloride with formalin, and Saccomanno fixative. The test samples to which these preservatives were added and the control samples for basal measurements were prepared from the urine pool obtained from urine samples taken from healthy volunteers. The urinary iodine measurements were performed following the calculated minimum number of replicates in these prepared samples. The data analysis of the interferences of the preservatives was performed based on the Clinical and Laboratory Standards Institute EP7-A2 guideline. The preservatives that had more acceptable effects on the urinary iodine measurement compared to the others were sodium carbonate (0.5% w/v) and thymol (10% w/v) with isopropanol (0.25% v/v) for 24-hour storage at room temperature. This report presented reliable and usable data revealing the effects of preservatives, which are frequently used to maintain the integrity of urine samples for a 24-hour urine collection, on urinary iodine measurement. There are need to reveal the possible effects of potential exogenous interfering substances and the pathological levels of endogenous analytes or shaped elements in the urine matrix on methods with routine clinical use in making medical decisions.

摘要

本报告旨在确定用于维持 24 小时尿液收集的尿液样本完整性的不同防腐剂对 Sandell-Kolthoff体外法测定尿碘的影响. 选择的防腐剂是盐酸、乙酸、硼酸、碳酸钠、氟化钠、百里酚加异丙醇、氯化钠加福尔马林和萨科曼诺固定剂。添加了这些防腐剂的测试样品和用于基础测量的对照样品是从取自健康志愿者的尿样中获得的尿池中制备的。在这些制备的样品中计算出最小重复次数后进行尿碘测量。防腐剂干扰的数据分析是根据临床和实验室标准协会EP7-A2指南进行的。与其他防腐剂相比，对尿碘测量具有更可接受影响的防腐剂是碳酸钠（0.5% w/v) 和百里酚 (10% w/v ) 与异丙醇 (0.25% v/v ) 在室温下储存 24 小时。该报告提供了可靠和可用的数据，揭示了防腐剂对尿碘测量的影响，防腐剂经常用于保持 24 小时尿液收集的尿液样本的完整性。需要揭示潜在的外源性干扰物质和尿液基质中内源性分析物或成形元素的病理水平对常规临床用于医疗决策的方法的可能影响。