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Low-TemperaturePlasma Probe forAmbient DesorptionIonization Jason D. HarperNicholas A. ChariparChristopher C. Mulligan2008 год

Low-Temperature Plasma Probe for Ambient Desorption Ionization
статья из журнала

Страница публикацииПубликация в OpenAlex
Аннотация: A low-temperature plasma (LTP) probe has been developed for ambient desorption ionization. An ac electric field is used to induce a dielectric barrier discharge through use of a specially designed electrode configuration. The low-temperature plasma is extracted from the probe where it interacts directly with the sample being analyzed, desorbing and ionizing surface molecules in the ambient environment. This allows experiments to be performed without damage to the sample or underlying substrate and, in the case of biological analysis on skin surfaces, without electrical shock or perceptible heating. Positive or negative ions are produced from a wide range of chemical compounds in the pure state and as mixtures in the gaseous, solution, or condensed phases, using He, Ar, N2, or ambient air as the discharge gas. Limited fragmentation occurs, although it is greater in the cases of the molecular than the atomic discharge gases. The effectiveness of the LTP probe has been demonstrated by recording characteristic mass spectra and tandem mass spectra of samples containing hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT) from poly(tetrafluoroethylene) (PTFE) surfaces where limits of detection are as low as 5 pg. Other performance characteristics, when using a commercial ion trap mass spectrometer, include 3−4 orders of magnitude linear dynamic range in favorable cases. Demonstration applications include direct analysis of cocaine from human skin, determination of active ingredients directly in drug tablets, and analysis of toxic and therapeutic compounds in complex biological samples. Ionization of chemicals directly from bulk aqueous solution has been demonstrated, where limits of detection are as low as 1 ppb. Large surface area sampling and control of fragmentation by a simple adjustment of the electrode configuration during operation are other demonstrated characteristics of the method.
Год издания: 2008
Авторы: Jason D. Harper, Nicholas A. Charipar, Christopher C. Mulligan, Xinrong Zhang, R. Graham Cooks, Zheng Ouyang
Издательство: American Chemical Society
Источник: Analytical Chemistry
Ключевые слова: Mass Spectrometry Techniques and Applications, Analytical chemistry methods development, Advanced Chemical Sensor Technologies
Другие ссылки: Analytical Chemistry (HTML)
PubMed (HTML)