PMID- 30583437 OWN - NLM STAT- MEDLINE DCOM- 20190211 LR - 20190215 IS - 1873-7072 (Electronic) IS - 0308-8146 (Linking) VI - 278 DP - 2019 Apr 25 TI - Quantitative determination of carbasalate calcium derived metabolites, acetylsalicylic acid and salicylic acid, in six animal foods using liquid-liquid extraction method coupled with liquid chromatography-tandem mass spectrometry. PG - 744-750 LID - S0308-8146(18)32063-6 [pii] LID - 10.1016/j.foodchem.2018.11.118 [doi] AB - This work describes a simple screening protocol for quantification of carbasalate calcium derived metabolites, acetylsalicylic acid (ASA) and salicylic acid (SA), in animal and aquatic food matrices using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The analytes were extracted from porcine muscle, milk, egg, shrimp, eel, and flatfish using acetonitrile, with the addition of formic acid as well as trifluoroacetic acid, followed by liquid-liquid purification with saturated n-hexane. A reverse-phase analytical column was employed with a mobile phase comprising (A) 1 mM ammonium acetate in distilled water and (B) methanol to achieve the best chromatographic separation. Matrix-matched calibration curves (R(2) >/= 0.9817) were constructed using six concentrations of 5, 10, 20, 30, 40, and 50 microg/kg in porcine muscle, milk, egg, shrimp, eel, and flatfish matrices. The calculated limits of quantification (LOQ) were 10 and 7 microg/kg, for ASA and SA, respectively. Recoveries of 67 to 102% with relative standard deviations (RSDs) of