Silver-organic coordination networks for magnetic solid-phase extraction of trihalomethanes from environmental water samples: experimental and theoretical calculation study

Trihalomethanes (THMs) are the primary toxic and carcinogenic byproducts during disinfection of drinking water. THMs have been frequently detected in water body and posed a huge threat to human health. Thus, analyzing the trace levels of THMs in an accurate and rapid method for water quality monitoring is important. In this paper, silver-based organic coordination networks (Ag-OCN) were fabricated with different diameters under mild pH condition. After modification with magnet, Fe3O4@ Ag-OCN as extractant was applied to the magnetic solid-phase extraction of THMs from water samples. Gas chromatography-tandem mass spectrometry was used for sample quantification and detection. The magnetic extractant displayed good linearity in the range of 0.03-10 ug/L, low limits of detection (1.41-10.13 ng/L), and good reproducibility (relative standard deviations < 6.31%). Moreover, density-functional theory (DFT) calculation was also applied to investigate the possible interaction mechanism. Combining the experimental data with theoretical calculation, results showed that Fe3O4@ Ag-OCN was a potential magnetic material for the enrichment and extraction of formed THMs at trace levels from water samples.