Issue 11, 2016

Plasma regime transition in a needle-FAPA desorption/ionization source

Abstract

The development of new Ambient Desorption/Ionization (ADI) sources has been an important research topic in recent years, arising from the need for reducing cost, analysis time and equipment complexity using mass spectrometry detection. This work presents a miniaturized plasma device with ADI capabilities based on a concentric FAPA source. The discharge device, the “needle-Flowing Atmospheric Pressure Afterglow” (n-FAPA), has been developed with easily replaceable commercial parts. In particular, the discharge is generated in flowing He using two concentric electrodes: a stainless steel capillary tube acting as the anode (outer electrode), and a hypodermic needle with a bevel-cut edge (inner electrode) acting as the cathode. Electrical and optical studies of n-FAPA have been carried out and the existence of a plasma regime transition (e.g. between normal glow and glow-to-arc transition), depending on the gas flow and current intensity conditions, has been shown. Rotational temperature and spatial distribution of temperatures have been calculated for both plasma regimes. Finally, the n-FAPA desorption/ionization source, coupled to a quadrupole mass spectrometer, has been tested in both plasma regimes for direct analysis of caffeine. Additionally, commercial drinks, carboxylic acids in water, and olive oil have been tested as model analytes.

Graphical abstract: Plasma regime transition in a needle-FAPA desorption/ionization source

Article information

Article type
Paper
Submitted
18 七月 2016
Accepted
27 九月 2016
First published
27 九月 2016

J. Anal. At. Spectrom., 2016,31, 2213-2222

Plasma regime transition in a needle-FAPA desorption/ionization source

J. Fandino, J. Orejas, J. Pisonero, P. Guillot, N. Bordel and A. Sanz-Medel, J. Anal. At. Spectrom., 2016, 31, 2213 DOI: 10.1039/C6JA00257A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements