Microplasma-based excitation/ionization source: from atomic to mass spectrometry

The excitation/ionization source is one of the key parts of analytical instruments. As a novel excitation/ionization source, microplasma ionization source has excellent characteristics including small size, low weight, power consumption, and cost, simple and adjustable structure, and high dissociation capability at a low working temperature, which are beneficial for the development of miniaturized instruments for real-time and on-site analysis. This review describes the recent advances in analytical techniques based on microplasma sources for the analysis of trace gaseous, aqueous, and solid species with emphasis on atomic and mass spectrometry. Microplasma source is useful for direct detection, also is typically used in conjunction with chromatography, vapor generation, lasers, and solid-phase extraction for analyzing multiple components in a complex matrix. Finally, future prospects of microplasma excitation/ionization source in miniaturized instruments are also described.