title: High-resolution elemental bioimaging of Ca, Mn, Fe, Co, Cu, and Zn employing LA-ICP-MS and hydrogen reaction gas.
abstract: Imaging of trace metal distribution in tissue sections by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is typically performed using spatial resolutions of 30 μm(2) and above. Higher resolution imaging is desirable for many biological applications in order to approach the dimensions of a single cell. The limiting factor for increasing resolution is sensitivity, where signal-to-noise ratios are poor due to inherent background spectral interferences and reduced sample volume with decreasing laser beam diameter. Several prominent spectral interferences are present for a number of biologically relevant isotopes, including the (40)Ar(16)O(+) spectral interference on (56)Fe(+). We examined if H(2) as a reaction gas could improve the analytical performance of imaging experiments for a range of masses with spectral interferences. At low (<1 mL min(-1)) H(2) flow rates, greater spectral interference due to H(+) adducts was observed for (55)Mn, (57)Fe, and (59)Co. At higher flow rates of up to 3 mL H(2) per minute, the spectral interferences were reduced leading to improvement in limits of analysis for masses with O- and N-based polyatomic interferences. Enhanced sensitivity with the reaction cell allowed construction of high resolution (6 μm(2)) imaging of (56)Fe in the mouse brain that approached the dimensions of single cells.
authors: Elemental Bio-imaging Facility, University of Technology, Sydney, Broadway, New South Wales, Australia.
authors: Jessica
authors: J
authors: Lear
authors: Dominic J
authors: DJ
authors: Hare
authors: Fred
authors: F
authors: Fryer
authors: Paul A
authors: PA
authors: Adlard
authors: David I
authors: DI
authors: Finkelstein
authors: Philip A
authors: PA
authors: Doble
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D002118:Calcium / Q000032:analysis; D003035:Cobalt / Q000032:analysis; D003300:Copper / Q000032:analysis; D005740:Gases / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D007501:Iron / Q000032:analysis; D008297:Male; D008345:Manganese / Q000032:analysis; D013058:Mass Spectrometry; D051379:Mice; D008810:Mice, Inbred C57BL; D059629:Signal-To-Noise Ratio; D014131:Trace Elements / Q000032:analysis*; D015032:Zinc / Q000032:analysis
chemical_list: D005740:Gases; D014131:Trace Elements; D003035:Cobalt; D008345:Manganese; D003300:Copper; D006859:Hydrogen; D007501:Iron; D015032:Zinc; D002118:Calcium