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

Simultaneous determination of Cd, Pb, Cu and Zn as total and labile fractions in soil using a small-sized electrothermal vaporization capacitively coupled plasma microtorch optical emission spectrometer after diffusive gradients in thin-film passive accumulation

“…The alternative is the unconventional technology using completely miniaturized instrumentation, in which the core element is a microplasma-based excitation/ionization source interfaced with a low-resolution microspectrometer or mass spectrometer. 16,17 This led to the development of very attractive analytical applications obeying the principles of green analytical chemistry (GAC) in spectrometry and, more recently, of white analytical chemistry (WAC). 18–22 Since introducing a gaseous sample into a microplasma was found to be a relatively simple task, the microplasma technology was mainly developed as a specific high-sensitivity detector by optical emission spectrometry (OES) and mass spectrometry (MS) in gas chromatography (GC) or as a device for introducing derivatized species of elements generated under UV irradiation by plasma, known as plasma-induced vapor generation technology.…”

“…23–28 However, there are several limitations in the development of microplasma analytical technologies, the most important of which are the lack of stability and poor excitation capability in the case of samples with a complex matrix, because of the low operating power. 16 Thus, the discharge stability is disturbed in the case of direct introduction of liquid samples because of low tolerance for water-loaded aerosols. It was shown that this shortcoming could be overcome by introducing liquid microsamples by ETV using the ideal miniaturized electrothermal vaporized-microplasma coupling, which provided the simultaneous determination of several elements with limits of detection (LODs) at the ng mL −1 or pg level, similar to ICP-OES.…”