Mesh-Collision Microtube Plasma Ion Source for Direct Mass Spectrometry Analysis.

Developing ambient ionization methods for direct mass spectrometry (MS) analysis is crucial for achieving sample-to-answer capabilities, especially for rapid analysis and monitoring in specific scenarios. Herein, a compact device is presented that utilizes mesh-collision microtube plasma (MC-μTP) ionization for direct online MS analysis. This device features a self-aspirating design that enables the direct analysis of various sample types. It includes an energy-efficient μTP generator with a single microneedle electrode and a high-efficiency molecule-ion reactor. The reactor integrates a screen mesh that disrupts and disperses the plasma plume, optimizing the mixing and contact probability between reactant ions and analyte molecules to enhance the ionization efficiency. For the data analysis, Venn diagrams were employed to facilitate the differential analysis of components in red wines from various regions. Furthermore, the release patterns of volatile organic compounds (VOCs) from leather products in a simulated high-temperature enclosed space were investigated through online monitoring. The integration of MC-μTP with a miniature mass spectrometer enabled the detection of eight distinct VOCs in leather products, showcasing promising potential for future on-site VOC monitoring within vehicle interiors.