Dissolved organic matter (DOM) is an ultracomplex mixture of organic compounds in the land/ocean–atmosphere interface. Normally, polar compounds from DOM are hardly retained by liquid chromatography (LC) columns for further analytical purposes. Here, we utilized Fourier transform ion cyclotron resonance mass spectrometry with LC for online analysis of DOM in river water and rainwater. With sophisticated instrumental optimization, different portions of metal salts, carboxyl-rich alicyclic molecules, organosulfates (OSs), and lignin-like compounds could be fully fractionated within one LC cycle (20 min). The complexity of the analyte was greatly reduced by LC separation, which therefore allows much better MS performance. Moreover, the compounds’ structures were characterized by tandem mass spectrometry (MS n ). The protocol presented herein offers a novel insight into the conventional LC-MS method, that it has the potential to investigate OSs and other components in DOM according to specific functional groups and heteroatoms and to explore their potential sources and reaction mechanisms.

Lignin is the second most abundant natural biopolymer, which is a potential alternative to conventional fossil fuels. It is also a promising material for the recovery of valuable chemicals such as aromatic compounds as well as an important biomarker for terrestrial organic matter. Lignin is currently produced in large quantities as a by-product of chemical pulping and cellulosic ethanol processes. Consequently, analytical methods are required to assess the content of valuable chemicals contained in these complex lignin wastes. This review is devoted to the application of mass spectrometry, including data analysis strategies, for the elemental and structural elucidation of lignin products. We describe and critically evaluate how these methods have contributed to progress and trends in the utilization of lignin in chemical synthesis, materials, energy, and geochemistry.

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Mass resolving power is one of the key features of Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS), which enables the molecular characterization of complex mixtures. Quadrupole (2ω) detection provides a significant step forward in FT‐ICR MS performance, as it doubles the resolving power for a given signal acquisition time. Whether this 2ω detection technique truly substitutes for a higher magnetic field remains unknown however. In this study, a residue oil sample was characterized using both a 2ω 7 Tesla FT‐ICR and a 15 Tesla FT‐ICR instrument, and analytical figures of merit were systematically compared. It was shown that 2ω 7T FT‐ICR MS provided comparable performance in the deep profiling of the complex oil sample, with better signal intensities and reproducibilities for absorption‐mode processing. The 15T FT‐ICR MS gave more precise measurements with better estimates of the sample's elemental compositions. To the best of our knowledge, this is the first published study, which thoroughly compared the performance of 2ω detection on a low magnetic field instrument with that of a high magnetic field FT‐ICR‐MS.

Rationale The development of appropriate analytical screening techniques for pharmaceuticals and personal care products (PPCPs) is the basis for studying the distribution and environmental impact of emerging contaminants (ECs). Mass spectrometry‐based screening methods vary with the complexity of the target compounds. It is challenging to balance both positive and negative ion quantification with a low detection limit. To establish a set of experimental methods including extraction, chromatography‐separation and mass spectrometry screening is one of the most important topics in PPCP research. This paper describes a universal and efficient qualification and quantification protocol for the simultaneous detection of 34 PPCPs in different environmental samples in a single analytical data acquisition run. Methods Thirty‐four representative PPCPs, which are widely distributed in the environment with high ecological toxicity and complex chemical structures, were selected as representative target ECs. The extraction of the target PPCPs was achieved using only one solid‐phase extraction cartridge without the need to adjust the pH of samples. The enriched samples were detected by LC–MS/MS in both positive and negative ion modes simultaneously. The protocol was evaluated based on the accuracy, precision, detection limits and matrix effects. Results This method achieved simultaneous detection of PPCPs in both positive and negative ion modes, with a single analytical cycle of 12 min. The observed SPE recoveries were between 40% and 115%. The instrumental detection limits (IDL) varied from 0.01 to 1 pg, and the method detection limits (MDL) were between 0.002 and 3.323 ng/l in different matrices. Most of the PPCPs were subjected to matrix suppression below 30%. The method was successfully applied for quantitative analysis of the PPCPs in different environmental samples, including river samples, wastewater treatment plant (WWTP) samples and soil samples. Conclusions This protocol developed a rapid and efficient detection method to simultaneous qualitative and quantitative 34 representative PPCPs in the environment. The IDL ranged from 0.01 to 1 pg and the MDL ranged from 0.002 to 3.323 ng/l in different matrices. The detection limit was one order of magnitude lower compared to previous studies. The protocol also provided a wide application range for different environmental matrices, which permitted the migration and transformation of PPCPs to be explored.