title: Imaging of biological tissues by desorption electrospray ionization mass spectrometry.
abstract: Mass spectrometry imaging (MSI) provides untargeted molecular information with the highest specificity and spatial resolution for investigating biological tissues at the hundreds to tens of microns scale. When performed under ambient conditions, sample pre-treatment becomes unnecessary, thus simplifying the protocol while maintaining the high quality of information obtained. Desorption electrospray ionization (DESI) is a spray-based ambient MSI technique that allows for the direct sampling of surfaces in the open air, even in vivo. When used with a software-controlled sample stage, the sample is rastered underneath the DESI ionization probe, and through the time domain, m/z information is correlated with the chemical species' spatial distribution. The fidelity of the DESI-MSI output depends on the source orientation and positioning with respect to the sample surface and mass spectrometer inlet. Herein, we review how to prepare tissue sections for DESI imaging and additional experimental conditions that directly affect image quality. Specifically, we describe the protocol for the imaging of rat brain tissue sections by DESI-MSI.
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of Technology, USA.
authors.forename: Rachel V
authors.initials: RV
authors.lastname: Bennet
authors.forename: Chaminda M
authors.initials: CM
authors.lastname: Gamage
authors.forename: Facundo M
authors.initials: FM
authors.lastname: Fernández
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D010767:Phosphorylcholine / Q000032:analysis / Q000737:chemistry; D051381:Rats; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*
chemical_list: D010767:Phosphorylcholine
references.citation: Rapid Commun Mass Spectrom. 2008 Sep;22(17):2639-44
references.pmid: 18666197
references.citation: Anal Bioanal Chem. 2011 Oct;401(6):1949-61
references.pmid: 21789488
references.citation: Mol Cell Proteomics. 2011 Feb;10(2):O110.004259
references.pmid: 20736411
references.citation: J Neurochem. 2001 May;77(4):1168-80
references.pmid: 11359882
references.citation: Angew Chem Int Ed Engl. 2010;49(5):873-6
references.pmid: 20041465
references.citation: Anal Chem. 2013 Jan 2;85(1):2-9
references.pmid: 23134552
references.citation: Angew Chem Int Ed Engl. 2006 Nov 6;45(43):7188-92
references.pmid: 17001721
references.citation: Biochim Biophys Acta. 2011 Nov;1811(11):946-60
references.pmid: 21645635
references.citation: Nat Protoc. 2008;3(3):517-24
references.pmid: 18323820
references.citation: Anal Chem. 2008 Feb 15;80(4):1027-32
references.pmid: 18193892
references.citation: Proc Natl Acad Sci U S A. 2009 May 5;106(18):7314-9
references.pmid: 19366672
references.citation: Anal Chem. 2012 Mar 6;84(5):2105-10
references.pmid: 22276611
references.citation: Anal Chem. 2007 Nov 1;79(21):8098-106
references.pmid: 17900146
references.citation: Mass Spectrom Rev. 2009 Nov-Dec;28(6):898-917
references.pmid: 19551695
references.citation: Proc Natl Acad Sci U S A. 2008 Nov 25;105(47):18120-5
references.pmid: 18697929
references.citation: Analyst. 2010 Jan;135(1):28-32
references.pmid: 20024177
references.citation: Chem Rev. 1999 Oct 13;99(10):2977-3006
references.pmid: 11749508
references.citation: J Mass Spectrom. 2007 Aug;42(8):1093-8
references.pmid: 17621389
references.citation: Anal Chem. 1997 Dec 1;69(23):4751-60
references.pmid: 9406525
references.citation: Anal Chem. 2006 Dec 15;78(24):8549-55
references.pmid: 17165852
references.citation: Anal Chem. 2005 Jul 15;77(14):4523-7
references.pmid: 16013869
references.citation: Biochemistry. 2007 May 29;46(21):6417-28
references.pmid: 17487985
references.citation: Anal Bioanal Chem. 2012 Aug;404(2):389-98
references.pmid: 22706326
references.citation: Analyst. 2010 Apr;135(4):731-7
references.pmid: 20349538
references.citation: Brain Res. 2000 Jun 9;867(1-2):9-18
references.pmid: 10837793
references.citation: Analyst. 2010 Apr;135(4):669-81
references.pmid: 20309441
references.citation: J Mass Spectrom. 2008 Apr;43(4):500-8
references.pmid: 18035855
references.citation: Cancer Res. 2012 Feb 1;72(3):645-54
references.pmid: 22139378
references.citation: Chem Commun (Camb). 2007 Oct 14;(38):3915-7
references.pmid: 17896031
references.citation: Science. 2004 Oct 15;306(5695):471-3
references.pmid: 15486296
references.citation: Mass Spectrom Rev. 2003 Sep-Oct;22(5):332-64
references.pmid: 12949918
references.citation: Anal Chem. 2009 Aug 15;81(16):6668-75
references.pmid: 19572562
references.citation: Anal Chem. 2005 Mar 1;77(5):1207-15
references.pmid: 15732898
references.citation: Int J Mass Spectrom. 2008 Dec 1;278(2-3):143-149
references.pmid: 19956342
references.citation: Anal Chem. 2006 Jul 15;78(14):4938-44
references.pmid: 16841914
references.citation: J Vis Exp. 2010 Sep 03;(43):
references.pmid: 20834223