Enhancing extraction performance of organophosphorus flame retardants in water samples using titanium hierarchical porous silica materials as sorbents.

A sorbent for the extraction of organophosphorus flame retardants has been proposed, based on UVM-7 (University of Valencia Materials) mesoporous silica doped with titanium. Designed cartridges have been applied to the extraction and preconcentration of flame retardants in water samples, followed by gas chromatography coupled to a mass spectrometry detector. Firstly, UVM-7 materials with different contents of titanium were synthesized and characterized by several techniques, thus confirming the proper mesoporous architecture. The potential of these materials was assessed in comparison with their morphological properties, resulting Ti50-UVM-7 the best solid phase. Several extraction parameters were also optimized. Analytical parameters were also evaluated, and limits of detection from 0.019 to 0.21 ng mL were obtained, as well as intra-day relative standard deviation below 11% for all analytes. Extraction efficiencies above 80% in water samples were achieved. The reusability of the material was also proved. Finally, the designed protocol was applied for the analysis of real water samples, and quantifiable concentrations of tris(2-chloroisopropyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPhP) were obtained in some samples. The method was compared with a United States Environmental Protection Agency general method with C18 cartridges.