title: Laser ablation based bioimaging with simultaneous elemental and molecular mass spectrometry: towards spatially resolved speciation analysis.
abstract: BACKGROUND
  Biological functions of metals are not only specified by the element itself, but also by its chemical form and by its organ, cell and subcellular location. The developed laser ablation based setup enables spatially resolved analysis with simultaneous elemental and molecular mass spectrometry (MS) and promises therefore localization, identification and quantification of metal or heteroelement-containing species in biological samples such as tissue sections.
  
  
  METHODS
  A UV laser ablation (LA) system is hyphenated in parallel both with an elemental and a molecular mass spectrometer via flow splitted transfer lines to simultaneously obtain data from both of the mass spectrometers. Elemental MS was performed using inductively coupled plasma (ICP)-MS, whereas atmospheric pressure chemical ionization (APCI)-MS with an orbitrap mass analyzer was utilized for molecular MS.
  
  
  RESULTS
  Simultaneous elemental and molecular MS imaging with high lateral resolution down to 25 µm was presented for the staining agents eosin Y and haematoxylin as well as for the chemotherapy drug cisplatin in thin tissue sections. For molecular MS, target compounds were identified by their exact masses and by characteristic fragment ions.
  
  
  CONCLUSIONS
  The first simultaneous elemental and molecular MS imaging approach based on laser ablation sampling was introduced for spatially resolved speciation analysis. The combination of the advantages of LA-ICP-MS such as low detection limits and high spatial resolution with information on the chemical identity promises not only localization of metals, but also identification of metal species in biological samples. Therefore, this novel technique opens up new possibilities to address complex challenges in life science research.
authors.affiliation: University of Münster, Institute of Inorganic and Analytical Chemistry, Corrensstr. 28/30, 49149, Münster, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Herdering
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Wehe
authors.forename: Olga
authors.initials: O
authors.lastname: Reifschneider
authors.forename: Indra
authors.initials: I
authors.lastname: Raj
authors.forename: Giuliano
authors.initials: G
authors.lastname: Ciarimboli
authors.forename: Kurt
authors.initials: K
authors.lastname: Diebold
authors.forename: Christoph
authors.initials: C
authors.lastname: Becker
authors.forename: Michael
authors.initials: M
authors.lastname: Sperling
authors.forename: Uwe
authors.initials: U
authors.lastname: Karst
mesh_terms: D000818:Animals; D007668:Kidney / Q000737:chemistry*; D053685:Laser Therapy; D008198:Lymph Nodes / Q000737:chemistry*; D013058:Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D051379:Mice; D008867:Microtomy; D057054:Molecular Imaging / Q000295:instrumentation / Q000379:methods*; D013194:Staining and Labeling