Detection limits of organic compounds achievable with intense, short-pulse lasers

Miles, Jordan; De Camillis, Simone; Alexander, Grace; Hamilton, Kathryn; Kelly, Thomas J.; Costello, John T.; Zepf, Matthew; Williams, Ian D.; Greenwood, Jason B.

Abstract

Many organic molecules have strong absorption bands which can be accessed by ultraviolet short pulse lasers to produce efficient ionization. This resonant multiphoton ionization scheme has already been exploited as an ionization source in time-of-flight mass spectrometers used for environmental trace analysis. In the present work we quantify the ultimate potential of this technique by measuring absolute ion yields produced from the interaction of 267 nm femtosecond laser pulses with the organic molecules indole and toluene, and gases Xe, N2 and O2. Using multiphoton ionization cross sections extracted from these results, we show that the laser pulse parameters required for real-time detection of aromatic molecules at concentrations of one part per trillion in air and a limit of detection of a few attomoles are achievable with presently available commercial laser systems. The potential applications for the analysis of human breath, blood and tissue samples are discussed.

Citation

Miles, J., De Camillis, S., Alexander, G., Hamilton, K., Kelly, T. J., Costello, J. T., Zepf, M., Williams, I. D., & Greenwood, J. B. (2015). Detection limits of organic compounds achievable with intense, short-pulse lasers. Analyst, 140(12), 4270-4276. https://doi.org/10.1039/c5an00529a

• Journal Article Type: Article
• Acceptance Date: Apr 15, 2015
• Publication Date: Jan 1, 2015
• Deposit Date: Jul 19, 2016
• Publicly Available Date: Jul 19, 2016
• Journal: Analyst
• Print ISSN: 0003-2654
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 140
• Issue: 12
• Pages: 4270-4276
• DOI: https://doi.org/10.1039/c5an00529a
• Keywords: Multiphoton ionization
• Public URL: https://hull-repository.worktribe.com/output/441292
• Publisher URL: http://pubs.rsc.org/en/Content/ArticleLanding/2015/AN/C5AN00529A#!divAbstract
• Additional Information: This is the authors accepted manuscript of an article published in: Analyst, 2015, v.140 issue 12.
• Contract Date: Jul 19, 2016