A convenient and sensitive method for haloacetic acid analysis in tap water by on-line field-amplified sample-stacking CE-ESI-MS

Abstract

In this study, we propose a simple strategy based on flow injection and field-amplified sample-stacking CE-ESI-MS/MS to analyze haloacetic acids (HAAs) in tap water. Tap water was passed through a desalination cartridge before field-amplified sample-stacking CE-ESI-MS/MS analysis to reduce sample salinity. With this treatment, the signals of the HAAs increased 300- to 1400-fold. The LODs for tap water analysis were in the range of 10 to 100 ng/L, except for the LOD of monochloroacetic acid (1 μg/L in selected-ion monitoring mode detection). The proposed method is fast, convenient, and sensitive enough to perform on-line analysis of five HAAs in the tap water of Taipei City. Four HAAs, including trichloroacetic acid, dichloroacetic acid, dibromoacetic acid, and monobromoacetic acid, were detected at concentrations of approximately 1.74, 1.15, 0.16, and 0.15 ppb, respectively.

Recent Studies on Online Sample Preconcentration Methods inCapillary Electrophoresis Coupled with Mass Spectrometry

“…They achieved totally 20,000-fold sensitivity increase including 125-fold improvement by FASS compared with conventional CE-MS approach. FASS was also employed for peptide analysis [51] and environmental analysis [52] where up to 330-fold sensitivity increase was achieved.…”

Field-enhanced sample injection micelle-to-solvent stacking capillary zone electrophoresis-electrospray ionization mass spectrometry of antibiotics in seawater after solid-phase extraction

“…The first stacking implemented in CE‐ESI‐MS was transient ITP . Since 2013, stacking in CE‐ESI‐MS has been achieved by transient ITP as well as by field amplification/enhancement and dynamic pH junction . Field‐enhanced sample injection (FESI) involves electrokinetic injection of a sample prepared in low conductivity diluent .…”

A fully-automated analyzer for determining haloacetic acid concentrations in drinking water

“…Researchers have embraced MS for HAAs analysis (Duan et al, 2011;Zhang et al, 2011;Li et al, 2012Li et al, , 2013Prieto-Blanco et al, 2012;Casas Ferreira et al, 2013;Hung and Her, 2013;Luo et al, 2013). Derivatization methods (Li et al, 2013) convert the HAAs to volatile species amenable for GC-MS analysis, similar to USEPA methods (USEPA, 1995(USEPA, , 2003 and others (Hammami and Driss, 2013;Liu et al, 2013), but have high labor costs.…”

“…An effort to automate the grab sample derivatization (Casas Ferreira et al, 2013) proved successful, thus minimizing the labor. Tandem MS techniques typically use some form of pretreatment or preconcentration coupled with GC (Li et al, 2013), high pressure liquid chromatography (HPLC) (Li et al, 2012;Prieto-Blanco et al, 2012), ultra pressure LC (UPLC) (Duan et al, 2011;Luo et al, 2013), or capillary electrophoresis (CE) (Zhang et al, 2011;Hung and Her, 2013) to detect and quantify HAAs. Two reports (Duan et al, 2011;Li et al, 2012) and USEPA 557 (USEPA, 2009) use direct aqueous injection and avoid complex pretreatment and preconcentration techniques with excellent results.…”