title: A comparison of sample preparation strategies for biological tissues and subsequent trace element analysis using LA-ICP-MS.
abstract: Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is one of the most commonly applied methods for lateral trace element distribution analysis in medical studies. Many improvements of the technique regarding quantification and achievable lateral resolution have been achieved in the last years. Nevertheless, sample preparation is also of major importance and the optimal sample preparation strategy still has not been defined. While conventional histology knows a number of sample pre-treatment strategies, little is known about the effect of these approaches on the lateral distributions of elements and/or their quantities in tissues. The technique of formalin fixation and paraffin embedding (FFPE) has emerged as the gold standard in tissue preparation. However, the potential use for elemental distribution studies is questionable due to a large number of sample preparation steps. In this work, LA-ICP-MS was used to examine the applicability of the FFPE sample preparation approach for elemental distribution studies. Qualitative elemental distributions as well as quantitative concentrations in cryo-cut tissues as well as FFPE samples were compared. Results showed that some metals (especially Na and K) are severely affected by the FFPE process, whereas others (e.g., Mn, Ni) are less influenced. Based on these results, a general recommendation can be given: FFPE samples are completely unsuitable for the analysis of alkaline metals. When analyzing transition metals, FFPE samples can give comparable results to snap-frozen tissues. Graphical abstract Sample preparation strategies for biological tissues are compared with regard to the elemental distributions and average trace element concentrations.
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9/164-IAC, 1060, Vienna, Austria.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Bonta
authors.affiliation: Department of Tumor Biology, National Koranyi Institute of Pulmonology, Budapest, 1121, Hungary.
authors.forename: Szilvia
authors.initials: S
authors.lastname: Török
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, 1090, Vienna, Austria.
authors.forename: Balazs
authors.initials: B
authors.lastname: Hegedus
authors.affiliation: Department of Tumor Biology, National Koranyi Institute of Pulmonology, Budapest, 1121, Hungary.|Division of Thoracic Surgery, Department of Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, 1090, Vienna, Austria.
authors.forename: Balazs
authors.initials: B
authors.lastname: Döme
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9/164-IAC, 1060, Vienna, Austria. andreas.limbeck@tuwien.ac.at.
authors.forename: Andreas
authors.initials: A
authors.lastname: Limbeck
mesh_terms: D005557:Formaldehyde; D013058:Mass Spectrometry / Q000379:methods*; D016612:Paraffin Embedding; D014131:Trace Elements / Q000032:analysis*
chemical_list: D014131:Trace Elements; D005557:Formaldehyde
keywords: Biological samples; Laser ablation; Mass spectrometry ICP-MS