An analytical method was developed and validated for the determination of three polyether ionophores (monensin, lasalocid, and salinomycin) in 60 samples of Brazilian Minas Frescal cheese by UHPLC-MS/MS. Linearity ranged from 1 to 8 μg kg-1 for monensin and salinomycin, and from 0.50 to 4 μg kg-1 for lasalocid. Limits of detection and quantitation were 0.50 μg kg-1 and 1 μg kg-1, respectively, for both monensin and salinomycin, and 0.25 μg kg-1 and 0.50 μg kg-1, respectively, for lasalocid. Recoveries were between 69% and 84% with coefficients of variation up to 16.28% for repeatability and 13.79% for intermediate precision. A total of 60 samples of Minas Frescal cheese were analysed and only monensin residues were found. Monensin was detected in 55% of the samples and quantified in 5 of them at mean levels varying from 1.00 to 1.73 μg kg-1. The proposed method demonstrated the suitability for monitoring these substances in cheese.

中文翻译：

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通过UHPLC-MS / MS测定Minas Frescal奶酪中的聚醚离子载体残基。

开发了一种分析方法，并通过UHPLC-MS / MS对60份巴西Minas Frescal奶酪样品中的三种聚醚离子载体（莫能菌素，拉索洛西德和盐霉素）进行了测定。莫能菌素和沙利霉素的线性范围为1至8μgkg-1，而拉沙利定的线性范围为0.50至4μgkg-1。莫能菌素和沙利霉素的检出限和定量限分别为0.50μgkg-1和1μgkg-1，拉拉西菌素的检出限和定量限分别为0.25μgkg-1和0.50μgkg-1。回收率在69％到84％之间，变异系数的重复性高达16.28％，中等精度的变异系数高达13.79％。共分析了60份Minas Frescal奶酪样品，仅发现莫能菌素残留。在55％的样品中检测到莫能菌素，并在5个样品中将其定量，平均水平为1.00至1.73μgkg-1。