[Determination of chlorate and perchlorate in infant formula by ultra-high performance liquid chromatography-tandem mass spectrometry].

OBJECTIVE

To establish a method for determination of perchlorate and chlorate in infant formula by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).

METHODS

Chlorate-(18)O_3 and perchlorate-(18)O_4 were added to the samples, and the filtrate was collected and analyzed by UPLC-MS/MS by vortex mixing, extraction, centrifugation and filtration. The mobile phase was 20 mmol/L ammonium formate and acetonitrile. The Waters Torus~(TM) DEA(2.1 mm×100 mm, 1.7 μm)column was used to separate chlorate and perchlorate. The negative spray ionization(ESI-) was used. The multi-response monitoring(MRM) mode was used for monitoring. The internal standard method was used for quantification.

RESULTS

The linear relationships of chlorate and perchlorate were good in the range of 0.2-200 μg/L and 0.1-100 μg/L(R~2& gt; 0.999), respectively. The detection limits(LOD, S/N=3) of chlorate and perchlorate were 0.35 μg/kg and 0.12 μg/kg, respectively, and the quantitative limits(LOQ, S/N=10) of chlorate and perchlorate were 1.16 μg/kg and 0.40 μg/kg, respectively. At the addition levels of 15.0, 75.0 and 150 μg/kg, the chlorate recovery was 91.9%-102.8% and the relative standard deviation(RSD, n=6) was 2.5%-4.4%. At the addition levels of 7.5, 37.5 and 75.0 μg/kg, the recovery rate of perchlorate was 91.3%-106.3% and the RSD(n=6) was 2.6%-3.9%. CONCLUSTION The method is simple, rapid, sensitive and accurate, and is suitable for simultaneous analysis of perchlorate and chlorate in various complex substrates.