Application of magnetized MOF-74 to phthalate esters extraction from Chinese liquor

In-situ induced ethanol-water phase separation extraction of phthalate esters in alcoholic liquid sample using potassium triphosphate and analysis by gas chromatography-mass spectrometry

A novel and efficient analytical method consisting of in-situ potassium triphosphate induced ethanol-water phase separation extraction and followed by gas chromatography-mass spectrometry (GC-MS) detection was developed for determination of eighteen phthalate esters (PAEs) in alcoholic liquid samples. Experimental parameters affecting the extraction efficiency were studied and optimized by univariate analysis. The effects of salt type and concentration, concentration of ethanol, redissolve solvent, vortex and standing time, solution pH on extraction efficiency were investigated. The developed method exhibited good linearity at a concentration range of 5-2500 μg·L^-1 for diisononyl phthalate and 1-500 μg·L^-1 for other PAEs. In addition, the coefficients of determination (R²) for all PAEs ranged from 0.9979 to 0.9999, the detection limits (LODs) and the limits of quantification (LOQs) were in the range of 0.014-0.530 μg·L^-1 and 0.047-1.767 μg·L^-1, respectively, the spiked recoveries were in the range of 92.2%-110.2% with the relative standard deviation (RSD) less than 8.6%. As ethanol within alcoholic liquid samples was used to separate PAEs with none solvent added at extraction processing, the proposed method could be considered simple and environmentally friendly.

Triazine covalent organic polymer coated stir bar sorptive extraction coupled with high performance liquid chromatography for the analysis of trace phthalate esters in mineral water and liquor samples

Cyanuric chloride and 4,4'-diamino-p-terphenyl were adopted as monomers to synthesize poly (4,4'-diamino-p-terphenyl-triazine) (PDT) covalent organic polymer. PDT coated stir bar was prepared and evaluated for the extraction of five phthalate esters (PAEs) with relatively lower logP values (2.7-4.9), including diethyl phthalate, diallyl phthalate, dipropyl phthalate, benzylbutyl phthalate and dibutyl phthalate. It exhibited higher extraction recovery (> 65%) and faster extraction kinetics (50 min vs 240 min) for target PAEs over commercial polydimethylsiloxane coated stir bar. Based on the superior performance, PDT coated stir bar sorptive extraction was combined with high-performance liquid chromatography-diode array detection for trace analysis of five PAEs plasticizers. The limits of detection for target PAEs were 0.04-0.27 μg/L, with the enrichment factors of 54-80-fold. The potential of the method was demonstrated by detecting five target PAEs in Chinese liquor and mineral water samples. No target analytes were detected in Chinese liquor sample, and recoveries of 85.4-109% were obtained for target analytes in spiked liquor samples; trace diethyl phthalate (1.19-2.98 μg/L) and dibutyl phthalate (0.77-0.91 μg/L) were detected in two mineral water samples, with recoveries of 85.4-117% and 87.4-117% respectively in spiked mineral water samples.

Application of an MOF-based dispersive micro solid phase extraction method followed by dispersive liquid–liquid microextraction for plasticizers’ detection and determination

In this research, MIL-68 (Al) was synthesized and used for the extraction of some plasticizers from various samples stored in plastic bottles.