title: Combination atmospheric pressure solids analysis probe and desorption electrospray ionization mass spectrometry ion source.
abstract: The atmospheric solids probe analysis (ASAP) probe was investigated as a means for conducting desorption electrospray ionization (DESI) using a commercially available ion source. Solid and liquid samples as well as a raw urine sample were placed on individual melting point tubes and were inserted into either a heated gas stream for ASAP analysis or a charged solvent spray for DESI-like experiments. Samples ranged in polarity, volatility, mass, (100-17,000 Da), and concentration (neat to submicromolar). Mass spectra of multiple samples were obtained within a single acquisition on a short time scale (<30 s per sample). The configuration of the ion source also allowed rapid switching (approximately 1 min) between ASAP, electrospray ionization (ESI), and DESI.
authors.affiliation: Department of Chemistry & Biochemistry, University of the Sciences in Philadelphia, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Lloyd
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Harron
authors.forename: Charles N
authors.initials: CN
authors.lastname: McEwen