Abstract:
For the US Food and Drug Administration\'s (FDA) mycotoxin program, the desired application of certified reference materials (CRMs) is primarily for validating methods for the determination of mycotoxins in foods and establishing metrological traceability of measurement results generated by such validated methods. The latter has been an important but insufficiently addressed challenge due to the lack of appropriate protocols and CRMs. Taking advantage of two recently available mycotoxin CRMs, OTAN-1 and Standard Reference Material (SRM) 1565, a protocol was developed for systematically examining uncertainty and establishing metrological traceability of measurement results of ochratoxin A (OTA) in corn through a series of calibration operations using the two CRMs. Instrument and method calibrations were performed using OTAN-1 and SRM 1565. The OTA value and its standard and expanded (k = 2, approximately 95% confidence) uncertainties were estimated from the calibration data and documented. These results demonstrate that the major contributing source of uncertainty is the sample matrix, highlighting the important role of the certified matrix reference material in method calibration. The value of OTA (38.5 ± 7.2 µg/g; 95% confidence interval) in the incurred sample was metrologically traceable to the International System of Units through two CRMs using the multi-laboratory validated liquid chromatography-mass spectrometry FDA compendial method. In addition, an alternative estimation of uncertainty was conducted using a one-point calibration, resulting in comparable uncertainty.
摘要:
对于美国食品和药物管理局(FDA)的霉菌毒素计划,认证参考材料(CRM)的理想应用主要是用于验证食品中霉菌毒素的测定方法,并建立由此类验证方法产生的测量结果的计量可追溯性。ThelatterhasbeenanimportantbutinsuitlyaddressedchallengeduetothelackofappropriateprotocolandCRMs.TakingadvantageoftworecentavailablemycotoxinCRMs,OTAN-1和标准参考材料(SRM)1565,开发了一种协议,用于通过使用两种CRM进行一系列校准操作来系统地检查玉米中曲霉毒素A(OTA)的测量结果的不确定性并建立计量可追溯性。使用OTAN-1和SRM1565进行仪器和方法校准。从校准数据估计OTA值及其标准和扩展(k=2,大约95%置信度)的不确定度并记录。这些结果表明,不确定性的主要来源是样本矩阵,强调认证矩阵参考材料在方法校准中的重要作用。产生的样品中的OTA值(38.5±7.2µg/g;95%置信区间)在计量上可以通过两个CRM使用多实验室验证的液相色谱-质谱FDA药典方法追溯到国际单位制。此外,使用单点校准进行了另一种不确定度估计,导致可比的不确定性。