Muscarella Marilena, Lo Magro Sonia, Palermo Carmen, Centonze Diego
Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, Foggia, via Manfredonia 20, 71100 Foggia, Italy.
Anal Chim Acta. 2007 Jul 2;594(2):257-64. doi: 10.1016/j.aca.2007.05.029. Epub 2007 May 25.
A high performance liquid chromatographic method with fluorimetric detection for the determination of aflatoxin M1 (AFM1) in milk has been optimized and validated according to Commission Decision 2002/657/EC by using the conventional validation approach. The procedure for determining selectivity, recovery, precision, decision limit (CC(alpha)), detection capability (CC(beta)) and ruggedness of the method has been reported. The results of the validation process demonstrate the agreement of the method with the provisions of Commission Regulation 401/2006/EC. The mean recovery calculated at three levels of fortification (0.5, 1.0, and 1.5-fold the MRL) was 91% and the maximum relative standard deviation value for the within-laboratory reproducibility was 15%. Limit of detection (LOD) and limit of quantitation (LOQ) values were 0.006 microg kg(-1) and 0.015 microg kg(-1) while the CC(alpha) and CC(beta) values were 0.058 microg kg(-1) and 0.065 microg kg(-1), respectively. The relative expanded measurement uncertainty of the method was 7%. The method was not affected by slight variations of some critical factors (ruggedness minor changes) as pre-treatment and clean-up of milk samples, thermal treatment and different storage conditions, as well as by major changes valued in terms of milk produced by different species (buffalo, goat and sheep). The method allowed accurate confirmation analyses of milk samples, resulted positive by the screening method. In fact, the Z-score values attained in a proficiency test round were well below the reference value of 1, proving the excellent laboratory performances.
已根据欧盟委员会第2002/657/EC号决定，采用传统验证方法，对一种用于测定牛奶中黄曲霉毒素M1（AFM1）的带荧光检测的高效液相色谱法进行了优化和验证。报告了该方法的选择性、回收率、精密度、决策限（CC(α)）、检测能力（CC(β)）和耐用性的测定程序。验证过程的结果表明该方法符合欧盟委员会第401/2006/EC号法规的规定。在三个加标水平（MRL的0.5、1.0和1.5倍）下计算的平均回收率为91%，实验室内再现性的最大相对标准偏差值为15%。检测限（LOD）和定量限（LOQ）值分别为0.006 μg kg⁻¹和0.015 μg kg⁻¹，而CC(α)和CC(β)值分别为0.058 μg kg⁻¹和0.065 μg kg⁻¹。该方法的相对扩展测量不确定度为7%。该方法不受牛奶样品预处理和净化、热处理和不同储存条件等一些关键因素的轻微变化（耐用性微小变化）的影响，也不受不同物种（水牛、山羊和绵羊）产奶方面重大变化的影响。该方法可对筛选方法检测为阳性的牛奶样品进行准确的确证分析。事实上，在一次能力验证测试轮次中获得的Z分数值远低于参考值1，证明了实验室的出色表现。
