Centrifugal microextraction tube-cloud point extraction coupled with gas chromatography for simultaneous determination of six phthalate esters in mineral water

A home-made centrifugal microextraction tube (CMET) was developed and applied to cloud point extraction coupled with microwave-assisted back extraction and gas chromatographic separation of six phthalate esters (PAEs) from mineral water. All phthalate esters were entrapped in the micelles of the non-ionic surfactant Triton X-114 and removed from the bulk phase by centrifugation. The obtained surfactant-rich phase was treated with water-immiscible solvents, and the target analytes were back extracted by short-term microwave application and determined by GC-FID directly. The whole process was finished in the CMET. The proposed method demonstrated good performance concerning linearity ( R 2 = 0.9977-0.9998), precision (2.3-5.7%), the limits of detection and quantitation (LOD, 11.5-19.3 μg L −1 ; LOQ, 37.0-63.3 μg L −1 ), spiked recoveries (89.1-96.3%) and enrichment factor (71-85). The proposed method was successfully applied for the determination of trace amount of phthalate esters in mineral water. DBP and BBP were found in actual mineral water samples. In this study, a centrifugal microextraction tube was first fabricated and used for CPE coupled microwave-assisted back-extraction of six phthalates from mineral water.