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Title: Surface Scanning Analysis of Planar Arrays of Analytes with Desorption Electrospray Ionization - Mass Spectrometry

Abstract

The analysis of analytes deposited on, separated on, or otherwise distributed about a planar surface using desorption electrospray ionization mass spectrometry in a surface scanning sampling mode was investigated. The physical regions of the surface-impacting solvent/gas jet desorption/ionization plume were described. Under the conditions typical for desorption electrospray ionization used here, the impact plume formed an elliptical desorption/ionization region on the surface. Most effective desorption/ionization was obtained from a smaller elliptical area within the larger impact region that was centered on a point on-axis from the sprayer tip to the surface. Maximum signal from a given amount of material on a surface was observed with proper plume and sample alignment when the diameter of the sample spot was less than the diameter of the central high efficiency desorption/ionization region of the impact plume. Solvent and gas flow out of this high efficiency desorption/ionization region was found to limit analyte accessibility to this region via a "washing effect" when analytes were on smooth surfaces or on surfaces for which the analyte had little affinity. As such, the direction of surface scanning and scan speed during an analysis was found to be important for maximizing signal levels and signal reproducibility on particularmore » surface types. Overall, the results presented illustrate means to improve analysis of sample spots on various types of surfaces using desorption electrospray ionization mass spectrometry in a surface scanning mode.« less

Authors:
 [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931005
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Analytical Chemistry; Journal Volume: 79; Journal Issue: 15
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; DESORPTION; SPRAYS; IONIZATION; MASS SPECTROSCOPY; SURFACE PROPERTIES; CHEMICAL ANALYSIS; PERFORMANCE; Desorption Electrospray; Ionization; Mass Spectrometry

Citation Formats

Pasilis, Sofie P, Kertesz, Vilmos, and Van Berkel, Gary J. Surface Scanning Analysis of Planar Arrays of Analytes with Desorption Electrospray Ionization - Mass Spectrometry. United States: N. p., 2007. Web. doi:10.1021/ac070527v.
Pasilis, Sofie P, Kertesz, Vilmos, & Van Berkel, Gary J. Surface Scanning Analysis of Planar Arrays of Analytes with Desorption Electrospray Ionization - Mass Spectrometry. United States. doi:10.1021/ac070527v.
Pasilis, Sofie P, Kertesz, Vilmos, and Van Berkel, Gary J. Mon . "Surface Scanning Analysis of Planar Arrays of Analytes with Desorption Electrospray Ionization - Mass Spectrometry". United States. doi:10.1021/ac070527v.
@article{osti_931005,
title = {Surface Scanning Analysis of Planar Arrays of Analytes with Desorption Electrospray Ionization - Mass Spectrometry},
author = {Pasilis, Sofie P and Kertesz, Vilmos and Van Berkel, Gary J},
abstractNote = {The analysis of analytes deposited on, separated on, or otherwise distributed about a planar surface using desorption electrospray ionization mass spectrometry in a surface scanning sampling mode was investigated. The physical regions of the surface-impacting solvent/gas jet desorption/ionization plume were described. Under the conditions typical for desorption electrospray ionization used here, the impact plume formed an elliptical desorption/ionization region on the surface. Most effective desorption/ionization was obtained from a smaller elliptical area within the larger impact region that was centered on a point on-axis from the sprayer tip to the surface. Maximum signal from a given amount of material on a surface was observed with proper plume and sample alignment when the diameter of the sample spot was less than the diameter of the central high efficiency desorption/ionization region of the impact plume. Solvent and gas flow out of this high efficiency desorption/ionization region was found to limit analyte accessibility to this region via a "washing effect" when analytes were on smooth surfaces or on surfaces for which the analyte had little affinity. As such, the direction of surface scanning and scan speed during an analysis was found to be important for maximizing signal levels and signal reproducibility on particular surface types. Overall, the results presented illustrate means to improve analysis of sample spots on various types of surfaces using desorption electrospray ionization mass spectrometry in a surface scanning mode.},
doi = {10.1021/ac070527v},
journal = {Analytical Chemistry},
number = 15,
volume = 79,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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