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Liu, Huwei

Publications and source records attributed to Liu, Huwei.

A Versatile Integrated Ambient Ionization Source Platform

The pursuit of high-throughput sample analysis from complex matrix demands development of multiple ionization techniques with complementary specialties. A versatile integrated ambient ionization source (iAmIS) platform is proposed in this work, based on the idea of integrating multiple functions, enhancing the efficiency of current ionization techniques, extending the applications, and decreasing the cost of the instrument. The design of the iAmIS platform combines flowing atmospheric pressure afterglow (FAPA) source/direct analysis in real time (DART), dielectric barrier discharge ionization (DBDI)/low-temperature plasma (LTP), desorption electrospray ionization (DESI), and laser desorption (LD) technique. All individual and combined ionization modes can be easily attained by modulating parameters. In particular, the FAPA/DART&DESI mode can realize the detection of polar and nonpolar compounds at the same time with two different ionization mechanisms: proton transfer and charge transfer. The introduction of LD contributes to the mass spectrometry imaging and the surface-assisted laser desorption (SALDI) under ambient condition. Compared with other individual or multi-mode ion source, the iAmIS platform provides the flexibility of choosing different ionization modes, broadens the scope of the analyte detection, and facilitates the analysis of complex samples. .

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Polymer‐based monolithic column with incorporated chiral metal–organic framework for enantioseparation of methyl phenyl sulfoxide using nano‐liquid chromatography

A new approach to the preparation of enantioselective porous polymer monolithic columns with incorporated chiral metal–organic framework for nano‐liquid chromatography has been developed. While no enantioseparation was achieved with monolithic poly(4‐vinylpyridine‐co‐ethylene dimethacrylate) column, excellent separations of both enantiomers of (±)‐methyl phenyl sulfoxide were achieved with its counterpart prepared after admixing metal–organic framework [Zn 2 (benzene dicarboxylate)(l‐lactic acid)(dmf)], which is synthesized from zinc nitrate, l ‐lactic acid, and benzene dicarboxylic acid in the polymerization mixture. These novel monolithic columns combined selectivity of the chiral framework with the excellent hydrodynamic properties of polymer monoliths, may provide a great impact on future studies in the field of chiral analysis by liquid chromatography.

Wang, Xin↗