Solid-phase extraction based on MIL-101 adsorbent followed by gas chromatography tandem mass spectrometry for the analysis of multiclass organic UV filters in water.

A metal organic framework material MIL-101 was developed as an effective solid-phase extraction adsorbent for the extraction of eleven UV filters compounds. The MIL-101 adsorbent was packed into a polypropylene cartridge and connected at the outlet tip with the Visiprep™ vacuum manifolds allowing process up to 12-port SPE samples, simultaneously. The extracted UV filters were quantified by gas chromatography-tandem mass spectrometry. Several parameters affecting the extraction efficiency of the target analytes, i.e. desorption conditions, sample pH, the addition of salt and sample volume were optimized by ANOVA analysis followed by a multifactorial design. The sample breakthrough volume of the developed method was also evaluated. The SPE-GC-MS/MS method was validated in terms of linearity (R ≥ 0.9973), accuracy (with satisfactory recovery from 82% to 105%), precision (relative standard deviation of less than 10%) and limits of detection ranging from 1.0 to 11.7 ng L. The validated method was successfully applied for the extraction and quantification of the target UV filters in different types of water samples, including lake, river, seawater and swimming pool waters. The most often found UV filters were octocrylene, 4-methylbencylidene camphor and homosalate that also came out with the highest concentrations, up to 4000 ng L, particularly in swimming pool waters.