Open AccessSalt tolerance of desorption electrospray ionization (DESI)
Author(s) -
Ayanna U. Jackson,
Nari Talaty,
R. Graham Cooks,
Gary J. Van Berkel
Publication year - 2007
Publication title -
journal of the american society for mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.961
H-Index - 127
eISSN - 1879-1123
pISSN - 1044-0305
DOI - 10.1016/j.jasms.2007.09.018
Subject(s) - chemistry , desorption electrospray ionization , extractive electrospray ionization , electrospray , salt (chemistry) , desorption , electrospray ionization , ionization , mass spectrometry , chromatography , analytical chemistry (journal) , chemical ionization , sample preparation in mass spectrometry , ion , organic chemistry , adsorption
The salt tolerance of desorption electrospray ionization (DESI) was systematically investigated by examining three different drug mixtures in the presence of 0, 0.2, 2, 5, 10, and 20% NaCl:KCl (1:1) from different surfaces. At physiological salt concentrations, the individual drugs in each mixture were observed in each experiment. Even at salt concentrations significantly above physiological levels, particular surfaces were effective in providing spectra that allowed the ready identification of the compounds of interest in low nanogram amounts. Salt adducts, which are observed even in the absence of added salt, could be eliminated by adding 0.1% 7 M ammonium acetate to the standard methanol:water (1:1) spray solvent. Comparison of the salt tolerance of DESI with that of electrospray ionization (ESI) demonstrated better signal/noise characteristics for DESI. The already high salt tolerance of DESI can be optimized further by appropriate choices of surface and spray solution.