High-resolution elemental bioimaging of Ca, Mn, Fe, Co, Cu, and Zn employing LA-ICP-MS and hydrogen reaction gas

Publication Type:
Journal Article
Analytical Chemistry, 2012, 84 (15), pp. 6707 - 6714
Issue Date:
Filename Description Size
Thumbnail2011008209OK.pdf608.95 kB
Adobe PDF
Full metadata record
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 μm2 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 40Ar 16O+ spectral interference on 56Fe+. We examined if H2 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) H2 flow rates, greater spectral interference due to H+ adducts was observed for 55Mn, 57Fe, and 59Co. At higher flow rates of up to 3 mL H2 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 μm2) imaging of 56Fe in the mouse brain that approached the dimensions of single cells. © 2012 American Chemical Society.
Please use this identifier to cite or link to this item: