A novel calibration strategy based on internal standard–spiked gelatine for quantitative bio-imaging by LA-ICP-MS: application to renal localization and quantification of uranium

Abstract

Mass spectrometry imaging (MSI) using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been employed for the elemental bio-distribution and quantification of uranium (U) in histological tissue sections of rodent kidneys. Kidneys were immediately immersed into 4% paraformaldehyde (PFA) solution for 24 h, Tissue-Tek O.C.T. Compound embedded and stored at − 80°C until cutting in a cryostat, and mounted in gel-covered glass slides. In order to assure complete ablation of sample, sample preparation and laser conditions were carefully optimized. In this work, a new analytical methodology is presented for performing quantitative laser ablation analyses based on internal standard (thulium, Tm)-spiked gelatine (10% m/v) for correction of matrix effects, lack of tissue homogeneity, and instrumental drift. In parallel, matrix-matched laboratory standards, dosed at different concentrations of U, were prepared from a pool of rat kidneys. The quantitative images of cryosections revealed heterogeneous distribution of uranium within the renal tissue, because the cortical concentration was up to 120fold higher than the medullary concentration.

To-Do and Not-To-Do in Model Studies of the Uptake, Fate and Metabolism of Metal-Containing Nanoparticles in Plants

“…LA-ICP-MS can also provide quantitative information but requires the use and availability of matrix matching standards to constitute calibration curves and appropriate internal standards (IS) to compensate signal variation during laser beam-sample interaction, transportation of the aerosol, and instrumental drifts [52,53], making the analyses more complex. In addition, the use of a single imaging technique like LA-ICP-MS may result insufficient in studies at low concentrations, where the few observable NPs can be almost indistinguishable from naturally occurring NPs or other background signals [54].…”

Investigating the effect of species-specific calibration on the quantitative imaging of iron at mg kg−1 and selenium at μg kg−1 in tissue using laser ablation with ICP-QQQ-MS

“…However, for such purpose, normalisation to S would still be valuable for monitoring the performance of calibration standards prepared using homogenized tissue. The combination of reported approaches for tissue internal standardization 31,41 with the ndings of this study could potentially lead to success in future work with real sample applications.…”

Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry Imaging in Biology

“…146 Similarly, Grijalba et al used a metal spiked gelatin layer deposited on the sample in combination with matrix-matched standards for the quantification of U in rat kidneys. 154 Konz et al 76 developed a sputtering protocol to deposit thin (9 ± 1 nm) Au layers on human eye tissue (Figure 12). The 197 Au signal was used for internal standardization for Mg, Fe, and Cu and compared against 13 C normalization.…”

“…The combined ablation of samples and the PMMA substrate allowed monitoring of the spiked metals for normalization . Similarly, Grijalba et al used a metal spiked gelatin layer deposited on the sample in combination with matrix-matched standards for the quantification of U in rat kidneys . Konz et al developed a sputtering protocol to deposit thin (9 ± 1 nm) Au layers on human eye tissue (Figure ).…”