Electro-focusing liquid extractive surface analysis (EF-LESA) coupled to mass spectrometry.

ABSTRACT: Analysis of the chemical composition of surfaces by liquid sampling devices interfaced to mass spectrometry is attractive as the sample stream can be continuously monitored at good sensitivity and selectivity. A sampling probe has been constructed that takes discrete liquid samples (typically <100 nL) of a surface. It incorporates an electrostatic lens system, comprising three electrodes, to which static and pulsed voltages are applied to form a conical "liquid tip", employed to dissolve analytes at a surface. A prototype system demonstrates spatial resolution of 0.093 mm(2). Time of contact between the liquid tip and the surface is controlled to standardize extraction. Calibration graphs of different analyte concentrations on a stainless surface have been measured, together with the probe

SUBMITTER: Brenton AG 

PROVIDER: S-EPMC3982933 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature