Low-temperature plasma ionization ion mobility spectrometry
1Department of Chemistry, Isfahan University of Technology, Isfahan, Iran. jafari@cc.iut.ac.ir
Analytical Chemistry
|January 4, 2011
Summary
Low-temperature plasma (LTP) is a novel ionization source for ion mobility spectrometry (IMS), enabling direct analysis of diverse compounds. This research validates LTP
Area of Science:
- Analytical Chemistry
- Physical Chemistry
Background:
- Ion mobility spectrometry (IMS) is a powerful analytical technique.
- Existing ionization sources for IMS often require sample preparation or specific conditions.
- Developing new, versatile ionization sources is crucial for expanding IMS applications.
Purpose of the Study:
- To investigate the feasibility of using low-temperature plasma (LTP) as an ionization source for IMS.
- To evaluate the performance of LTP for direct analysis of various chemical compounds.
- To assess the potential of LTP-IMS for portable analytical applications.
Main Methods:
- Investigated the effects of discharge gas flow rate, plasma voltage, and LTP positioning on IMS signals.
- Characterized positive and negative reactant ions generated by LTP, comparing them to corona discharge.
- Acquired ion mobility spectra for explosives, drugs, and amines in both positive and negative modes.
- Calculated reduced ion mobility values (K(0)) and determined figures of merit for acetaminophen.
Main Results:
- LTP successfully generated characteristic positive (proton clusters) and negative (e.g., NO(x)(-)) reactant ions.
- Direct ionization of gaseous samples and desorption/ionization of liquids/solids by LTP were achieved.
- Ion mobility spectra and reduced mobility values were obtained for tested compounds.
- Promising figures of merit were determined for acetaminophen using the LTP-IMS method.
Conclusions:
- Low-temperature plasma (LTP) is a viable and effective ionization source for ion mobility spectrometry (IMS).
- LTP-IMS facilitates direct analysis of diverse compounds, enhancing IMS portability.
- The findings support the use of LTP as a versatile desorption/ionization source for analytical applications.
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