High-throughput screening of PAHs and polar trace contaminants in water matrices by direct solid-phase microextraction coupled to a dielectric barrier discharge ionization source.

This study, moreover, shows that intrinsically poorer ionization efficiencies for low-polarity compounds (such as polycyclic aromatic hydrocarbons, PAHs), which precluded their ultra-trace detection, can be partially overcome by adding dopants and lowering the LODs into the pg mL-1 range. Results also show that the presence of these dopants greatly affects the ionization mechanism, resulting in the preferential formation of radical cations versus protonated PAHs. As a proof of concept, this method was applied to the detection of organic microcontaminants in different water matrices (such as tap, ground, and treated wastewater). Common contaminants (e.g., DEET, benzotriazole, β-estradiol) were tentatively detected and, if above the LOQ, quantified (i.e., DEET at 30 pg mL-1). These promising results evidence that this approach is interesting for quick (field) screening methods, and the newly increased efficiency for a larger polarity range additionally expands the range of possible applications. PMID: 30032761 [PubMed]
Source: Analytica Chimica Acta - Category: Chemistry Authors: Tags: Anal Chim Acta Source Type: research