Isotopically Enriched Tracers and Inductively Coupled Plasma Mass Spectrometry Methodologies to Study Zinc Supplementation in Single-Cells of Retinal Pigment Epithelium in Vitro

Abstract

Mass spectrometry-based techniques, such as inductively coupled plasma -mass spectrometry (ICP-MS) and laser ablation (LA) ICP-MS, combined with isotope pattern deconvolution mathematical tool are proposed for a better understanding of supplementation studies in cultured cells. An in vitro model of human retinal pigment epithelium (HRPEvs) cells was treated with different concentrations (0-150 m Zn, 1 mL) of enriched stable isotope tracers of Zn in the form of sulfate and/or gluconate.Supplementations with t68 ZnSO 4 or t70 Zn-gluconate alone, and in combination (1:1 molar ratio) were investigated to evaluate the exogenous contribution and distribution of Zn in the treated cells. In order to obtain not only the Zn concentration for a cell population (mineralized cells) but also single cell information about the contribution of exogenous Zn and their distribution within micrometer cells structures, LA-ICP-MS was employed to directly analyze cryopreserved cells. nat Zn, t68 Zn and t70 Zn molar fraction images obtained from cells and cells aggregates allowed confirming the uptake of exogenous Zn by HRPEsv cells, being t68 Zn and t70 Zn molar fractions close to 1 in the cell nuclei. Under the selected experimental conditions tested (24 h treatments), no significant differences were obtained in the Zn distribution depending on its chemical form.Age-related macular degeneration (AMD) is a progressive neurodegenerative eye disease characterized by the formation of extracellular deposits between the retinal pigment epithelium (RPE) and the Bruch's membrane. 1 During ageing, oxidative damage to retina and RPE as well as inflammatory-mediated processes contribute to the development and progression of AMD. 2 Unfortunately, no effective treatments are

Isotopic measurements using ICP-MS: a tutorial review

“…130 In the next few years we expect to see advances in particular areas of isotopic measurements. For example, elemental imaging of biological tissues using LA-ICP-MS will allow detections of newly incorporated elements that use isotope labeling 10,131 in biological research. The eld of nanoparticles will also benet from the use of enriched isotopes, both for characterization 132 and analysis.…”

Facets of ICP-MS and their potential in the medical sciences—Part 1: fundamentals, stand-alone and hyphenated techniques

“…Employment of MC instrumentation improved precision to spatially resolve isotope ratios [ 248 ]. In a recent study, Rodriguez-Menendez et al [ 249 ] applied LA-ICP-MS to investigate Zn-based tracers and their uptake by HRPEsv cells. The authors used IPD to differentiate and map endogenous Zn and tracer isotopes, independently (Fig.…”

“…Reprinted with permission from S. Rodriguez-Menendez, B. Fernandez, H. Gonzalez-Iglesias, M. Garcia, L. Alvarez, J.I. Garcia Alonso, R. Pereiro, Isotopically enriched tracers and inductively coupled plasma mass spectrometry methodologies to study zinc supplementation in single-cell of retinal pigment epithelium in vitro, Analytical Chemistry 2019, 91, 7, 4488-4495 [ 249 ]. Copyright (2019), American Chemical Society.…”

ICP-MS and Photothermal Dual-Readout Assay for Ultrasensitive and Point-of-Care Detection of Pancreatic Cancer Exosomes

“…In recent years, ICP-MS, with the superior advantages of high sensitivity, outstanding stability, and a broad dynamic linear range, has been applied in numerous bioassays, such as nucleic acid detection, , protein quantification, , and single cell analysis. , ICP-MS is expected to be a powerful technique for ultrasensitive exosome quantification. However, to the best of our knowledge, there is currently no reports of the use of ICP-MS to determine exosomes.…”