Atmospheric Pressure Mass Spectrometry: Pre-concentration

Adam WilliamsREU Summer 2013 Participant

Student of Electrical Engineering

Bonner Denton LabDr. M. Bonner Denton Dr. Jeffery Babis

Contact Information: adamwilliams1@email.arizona.edu

Applications of Atmospheric Pressure Mass Spectrometers

• Detecting Illegal Drugs

• Atmospheric Testing

• Emissions Testing

* 1

* 2

* 3

Ion Mobility Spectrometry Defined

• Principles, methods, and instrumentation for characterizing chemical substances on the basis of velocity of gas-phase ions in an electric field

Eiceman, G. A., & Karpas, Z. (2005). Ion mobility spectrometry. Boca Raton: CRC Press.., 5

Overview of Ion Mobility Spectrometry

Carr, T. W. (1984). Plasma chromatography. New York: Plenum Press., 32

𝐾 =𝑣𝑑𝐸

𝑣𝑑 =𝑙𝑑𝑡

Gas phase particles

Carr, T. W. (1984). Plasma chromatography. New York: Plenum Press., 35

Sample Graph

Pre-concentration in Atmospheric Pressure Mass Spectrometry

• Analysis requires larger signal-to-noise ratio

• Analyte passed through cool trapping medium

• Medium rapidly heated to allow larger concentration of analyte to pass through spectrometer

Requirements for Pre-concentrator Controller

Computer controlled activation/deactivation

Timer circuit to prevent overheating

Activation of step-down transformer to generate enough current for heating to release analyte

Pre-Concentrator Controller (with 555 Timer) Circuit

Pre-Concentrator Controller Circuitboard

Pre-Concentrator Controller Box and Transformer

2,4 Dinitrotoluene CH3C6H3(NO2)2

“DNT”

Sample Analyte

Actual Sample Size

Results

Without Pre-Concentration Using Pre-Concentration

• +4:1 sample signal boost with 2,4 Dinitrotoluene

Acknowledgments

• National Science Foundation

• REU Professors and Mentors– Dr. Srinivas Manne, Dr. Anthony Pitucco

– Nikita Kirnosov, Amber Hawkins, Rebekah Cross

– Dr. William Bickel, Dr. Koen Visscher

• U of A Laboratories

• Bonner Denton Lab Group– Dr. M Bonner Denton

– Dr. Jeffery Babis

– Dr. Roger Sperline

– Undergrad and Grad Assistants

References

• Eiceman, G. A., & Karpas, Z. (2005). Ion mobility spectrometry. Boca Raton: CRC Press.

• Carr, T. W. (1984). Plasma chromatography. New York: Plenum Press.• *1 http://tvshows.alphacoders.com/tv_shows/wallpapers/358

• *2 http://www.wallpapergate.com/wallpaper2410.html

• *3 http://captainkimo.com/smoke-stack-from-sugar-factory-in-belle-glade-florida/

Questions