Spengler, B, Anal. Chem.
87 (2015) 64.
Smith, D F, Kiss, A, Leach, F R III, Robinson, E W, Pasa-Tolic, L & Heeren, R M A, Anal. Bioanal. Chem.
405 (2013) 6069.
Yang, J Y, Phelan, V V, Simkovsky, R, Watrous, J D, Trial, R M, Fleming, T C, Wenter, R, Moore, B S, Golden, S S, Pogliano, K & Dorrestein, P C, J. Bacteriol.
194 (2012) 6023.
Alexandrov, T, Becker, M, Deininger, S-O, Ernst, G, Wehder, L, Grasmair, M, von Eggeling, F, Thiele, H & Maass, P, J. Proteome Res.
9 (2010) 6535.
 This work was performed at EMSL, a national scientific user facility sponsored by the Office of Biological and Environmental Research, U.S. Department of Energy (DOE). EMSL is located at PNNL, a multidisciplinary national laboratory operated by Battelle for the U.S. DOE. We would like to thank Professor Pieter Dorrestein (UCSD) for his many useful discussions, and Mr. Alain Creissen is thanked for his contributions and discussions in optimizing the TM-Sprayer for matrix applications..