Mobile Mass Spectrometry Research Articles

Rapid Advances in Mobile Mass Spectrometry Enhance Tracer Hydrology and Water Management

AbstractDissolved gases, including noble gases, are versatile environmental tracers. Historically, the application of dissolved (noble) gases as tracers in hydrology used to be limited because their measurement required expensive, laboratory‐based instrumentation operated by highly trained personnel. Here, we highlight recent advances in mobile mass spectrometry (MS) methods for noble and other dissolved gases, which enable low cost, high‐throughput, real‐time measurements. We also present applications using mobile MS to quantify hydrological and biogeochemical processes in groundwater and surface waters and to assess hazards and risks to aquatic environments. Finally, we indicate potential future applications of these instruments to enhance hydrological research.

Identification of Impurities in 5-Aminolevulinic Acid by Two-Dimensional Column-Switching Liquid Chromatography Coupled with Linear Ion Trap Mass Spectrometry

Identification of impurities in 5-aminolevulinic acid (ALA) by mass spectrometry is difficult, because MS-incompatible mobile phases, such as phosphate buffers or ion-pair reagents, need to be used to separate the major component from impurities. In this study, the unknown impurities in ALA have been identified by two-dimensional (2D) column-switching high-performance liquid chromatography (HPLC) coupled with linear ion trap mass spectrometry (LIT MS). The first-dimensional analytical column was a Gemini C18 (150 mm × 4.6 mm, 5 μm) with a non-volatile salt mobile phase at a flow rate of 1.0 mL min−1, and the second-dimensional analytical column was a ZORBAX SB C8 (150 mm × 4.6 mm, 3.5 μm) with a volatile salt mobile phase at a flow rate of 1.0 mL min−1. The detection wavelength was 205 nm. Mass spectra were acquired with an ESI source, in both positive and negative ion modes. Six impurities were identified by their MS2 and MS3 fragments, and the mass fragmentation patterns and structural assignments of these impurities were studied. The results obtained by the two-dimensional column-switching method were further compared with those of the conventional one-dimensional normal-phase HPLC–MS using an amide column and an MS-compatible mobile phase for separation. The two-dimensional column-switching method described herein proved to be advantageous in terms of the number of impurities identified. The column-switching and online demineralization technique made the mobile phase conditions compatible with mass spectrometry. Thus, the method solves the problem of incompatibility between non-volatile salt mobile phases and mass spectrometry, making it worthy of popularization and application in impurity identification.

Mobile mass spectrometry; a decade of field applications

In recent years, mobile mass spectrometry has gained great importance for on-site analytical applications in environmental investigations and emergency analytical determinations. An interesting path has been followed to reach today's state-of-the-art ruggedized mobile and portable instrumentation in gas chromatography-mass spectrometry (GC-MS). The development of automated sampling systems was also a fundamental support in this transition phase. Fast, routine, and computer-assisted GC-MS analysis on-site usually requires analytical equipment, which should be easy-to-work and hard-to-break, with short down-times. Fast mass spectrometric on-site analyses help protect the population in chemical accidents and help reduce the field investigation times dramatically.

Mobile mass spectrometry. A new technique for rapid environmental analysis

Mobile mass spectrometry. A new technique for rapid environmental analysis

Mobile mass spectrometry. A new technique for rapid environmental analysis

Mobile mass spectrometry. A new technique for rapid environmental analysis