Online Coupling of In-Tube Solid-Phase Microextraction with Direct Analysis in Real Time Mass Spectrometry for Rapid Determination of Triazine Herbicides in Water Using Carbon-Nanotubes-Incorporated Polymer Monolith

Abstract

Online coupling of in-tube solid phase microextraction (IT-SPME) with direct analysis in real time mass spectrometry (DART-MS) was realized for the first time and applied in the analysis of triazine herbicides in lake water and orange juice. We incorporated single-wall carbon nanotubes (SWNTs) into a polymer monolith containing methacrylic acid (MAA) and ethylene dimethacrylate (EDMA) to form a novel poly(methacrylic acid-co-ethylene dimethacrylate-co-single wall carbon nanotubes) (poly(MAA-EDMA-SWNT)) monolith, which was then used in IT-SPME for enrichment of six triazine herbicides from water samples. With the online combination of IT-SPME with DART-MS, the analytes desorbed from the monolith were directly ionized by DART and transferred into MS for detection, thus rapid determination was achieved. Compared with regular DART-MS method, this online IT-SPME-DART-MS method was more sensitive and reproducible, because of the IT-SPME procedures and the isotope-labeled internal standard used in the experiment. Six triazine herbicides were determined simultaneously using this method with good linearity (R(2) > 0.998). The limit of quantification (signal-to-noise ratio of S/N = 10) of the six herbicides were only 0.06-0.46 ng/mL. The proposed method has been applied to determine triazine herbicides in lake water and orange juice, showing satisfactory recovery (85%-106%) and reproducibility (relative standard deviation of RSD = 3.1%-10.9%).

Differentiation of Disaccharide Isomers by Temperature-Dependent In-Source Decay (TDISD) and DART-Q-TOF MS/MS

“…Compared with conventional mass spectrometry (MS) techniques, 14]. For instance, Liu's research team reported its application to the rapid determination of triazine herbicides in water [10]. Chernetsova and collaborators used DART MS to identify phenolic compounds in propolis [14].…”

Direct Analysis in Real Time Mass Spectrometry: a Powerful Tool for Fast Analysis

“…47 After direct extractions for 30 times, this coating still showed reproducible extraction efficiency. Recently, Wang and coworkers developed the interface of online coupling of in-tube solid-phase microextraction (IT-SPME) with DART-MS, as shown in Figure 3, 48 in wihch the single-wall carbon nanotubes incorporated monolith showed high affinity for six triazine herbicides. With the online combination of IT-SPME with DART-MS, the analytes desorbed from the monolith were directly ionized by DART and transferred into MS for detection, thus rapid determination was achieved.…”

A high throughput mass spectrometry screening analysis based on two-dimensional carbon microfiber fractionation system

“…Furthermore, direct MS injection of complex samples may result in a high background noise, making qualitative and quantitative analyses of trace compounds very difficult. To reduce ionization suppression effect and matrix interferences a preliminary sample preparation procedure is performed, requiring time and skilled personnel, but this operation substantially reduces the number of substances that can be detected [22,24,25]. There is then an urgent need of reliable and high-throughput screening and/or quantification methods for compound determination in real samples, ranging from low to high contents and from low to high polarities.…”