Abstract
•Extraction of BPA, MEL and DEHP from different matrixes.•Use of two SPE columns including normal and reversed phases.•Extraction of large volume of water and soft drinks.•Detection and quantification of trace amounts of the targeted analytes in different matrixes.•Application of two LC–TQ-MS methods for the analysis of targeted analytes.
Described below is an optimized solid-phase extraction method (SPE) for the simultaneous determination of three hazardous plastic additives. Two high-performance liquid chromatographic–electrospray ionization-mass spectrometric (HPLC–ESI-MS) methods were developed and validated to estimate the melamine (MEL), bis(2-ethylhexyl) phthalate (DEHP), and bisphenol A (BPA) contents in drinking water, syringes, soft drinks, and dry milk powder. One extraction procedure optimally recovered all three substances from the different matrices. Two extraction columns were combined and included a silica gel LiChroprep RP-2 column (20:1, g/g, top column) and a Sep-Pak with a C18 column (500mg, bottom column). The analytical column was an Agilent Eclipse XDB-C8 column, 4.6mm×150mm, 5μm, maintained at 50±2°C. MEL and DEHP were monitored by positive triple quad mass spectrometry (TQ-MS) using an acidic mobile phase, while BPA was monitored by negative TQ-MS using a mobile phase containing a 0.05% ammonia solution. The general linear range of the three compounds ranged from 12 to 1000pg/μL in the injected solution (25μL). The average extraction recoveries were within the range of 83.0–102.5%. Relatively high concentrations of BPA and DEHP were found in the milk powder and sterile syringes.