Supplementary Information for
A Membrane Introduction Mass Spectrometer Utilizing Ion-Molecule Reactions
for the On-line Speciation and Quantitation of Volatile Organic Molecules
Nicholas G. Davey1,2; Ryan J. Bell2,3; Erik T. Krogh1,2; Chris G. Gill*1,2
1
2
Chemistry Department, University of Victoria, Victoria, B.C., Canada
Applied Environmental Research Laboratories (AERL), Chemistry Department,
Vancouver Island University, Nanaimo, B.C., Canada
3
Present address: Beaver Creek Analytical LLC, Boulder, CO, USA
*Address reprint requests to:
Chris G. Gill
Applied Environmental Research Laboratories (AERL)
Chemistry Department, Vancouver Island University
900 Fifth Street, Nanaimo, BC, Canada V9R 5S5
1-250-753-3245, local 2303
Chris.Gill@viu.ca
Supplementary Information Figure Legends
Figure S1: Pathways for common positive ion formation from different precursors in
EI.
Figure S2: (a) Chloroform CI mass spectrum of benzene and proposed reaction
pathway for adduct ion formation with CHCl2+. (b) Chloroform-d CI mass spectrum
of benzene and proposed reaction pathway for isotopically labelled product ion.
Figure S3: EI mass spectrum for ethylbenzene (50 ppbv).
Figure S4: Chloroform reagent ion (CHCl2+) population as a function of reaction
time with no analytes added to the system.
Figure S5. (a) Chloroform reagent ion (Rg) signal intensity depletion with increased
concentration of ethylbenzene (Eb) analyte at constant reaction time (2 seconds). Inset
mass spectrum taken at 284 ppbv ethylbenzene. (b) Direct calibration of ethylbenzene
using chloroform as CI reagent ion precursor and the resulting adduct ion (m/z 153)
for quantitation.