Alternative splicing generates multiple mRNA isoforms, driving protein diversity and tumor heterogeneity. However, achieving multiplexed quantification of splice variants at single-cell resolution remains a significant challenge. Herein, we present a programmable self-priming lanthanide-labeled DNA probe (PSPLn) strategy for sensitive, multiplexed single-cell quantification of MDM2 splice variants in glioma-related cell models. By precisely tuning the number of adenines in the probe sequence and conjugating distinct lanthanide-DOTA complexes through click chemistry, we achieve junction-specific recognition and tunable signal amplification for splice-variant-resolved analysis. Coupling these probes with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), PSPLn enables high-throughput, single-cell readout of multiple MDM2 splice variants within individual cells. Application to U87 and U251 glioblastoma cell lines and the oligodendrocytic MO3.13 cell line reveals variant-dependent expression profiles and intervariant correlation patterns reflecting tumor heterogeneity. This platform overcomes the limitations of bulk and sequencing methods, offering a versatile tool for splice biomarker discovery and precision diagnostics in oncology.

To gain deeper insights into the manufacturing techniques and raw material sources of the glass beads collected from the Nanhai I shipwreck dating from Southern Song Dynasty, a comprehensive analysis was conducted on the beads using digital microscopy, X-ray micro-computed tomography (Micro-CT), micro X-ray fluorescence spectrometry (μ-XRF), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), Scanning Electron Microscope- Energy Dispersive X-ray Spectrometer (SEM-EDS), multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) and micro-Raman spectroscopy. The results indicate that these beads are typical Chinese potash-lead and lead silicate glasses, manufactured primarily using the coiling technique. The opaque yellow coloration was obtained with the use of lead stannate (lead-tin yellow type II) as both a colorant and opacifier. The orange interior of black glass beads was colored by the combined use of Cu2O and CuO, while the surface of black beads exhibit signs of weathering from the presence of such corrosion products as Pb2CO3Cl2, PbS, and 2PbCO3·Pb(OH)2. The technological lineage of these lead-(potash) beads is discussed below from the perspectives of their compositional system and the nature of the opacifiers that were used, linking them to Han Dynasty potash-lead glass from Lingnan. Based on the results of trace element and lead isotope analysis, the provenance of the raw material used to these glass beads was also investigated.

Integrated geological datasets for the Zandrivierspoort Formation banded iron formation, Rhenosterkoppies Greenstone Belt, South Africa

Although species identification is crucial for land-snail eggs, limited effort has been made to identify the species responsible for producing the eggs. In this study, we used laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to measure 54 elements in both the eggshells and adult shells of Bradybaena ravida and Cathaica fasciola and we used scanning electron microscope (SEM) to analyze the microstructure of the eggshells of the two species. Our results reveal that while the concentrations of Sr, Na, Mg, P, and Ba in the adult shells of the two species are not distinct, they are distinct or partially distinct between their eggshells, indicating that these elements have the potential to differentiate the eggs of the two species. Moreover, the eggshells of C. fasciola exhibit a blocky morphology without cavities, whereas those of B. ravida, while also blocky, contain irregular cavities. These distinct elemental and microstructural characteristics enable the effective differentiation of the eggs of B. ravida and C. fasciola. Our study demonstrates the feasibility of a critical microscopic methodology for identifying land-snail eggs at the genus/species level, thereby facilitating deeper exploration of their value in understanding biological, climatic, and ecological changes.

Color genesis and luminescence of apatite from Xuebaoding, Sichuan, Southwest China: Insights from multi-spectroscopic analyses and chemical compositions.

Diffusive gradients in thin films (DGT) coupled with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is increasingly applied for high-resolution chemical imaging of metal solutes, yet its effective lateral resolution has not been quantitatively assessed. This study provides the first targeted investigation of the lateral resolution achievable with state-of-the-art DGT LA-ICP-MS using copper (Cu) as a model analyte in three complementary experimental designs that isolate diffusion-controlled, geometry-controlled, and material-controlled constraints: (i) Controlled solute transport through a polytetrafluoroethylene (PTFE) foil with 5-100µm holes revealed differential time-dependent broadening of solute and matrix patterns and the transition from geometry-preserving to diffusion-dominated behaviour. Full width at half maximum/minimum (FWHM)-based analysis showed very small apparent lateral "imaging-blur" coefficients for DGT-bound metals (Cu/Zn ≈10-15-10-13 m2s-1), i.e., several orders of magnitude lower than typical ionic diffusion in hydrogels (≈10-10 m2s-1), consistent with rapid immobilization at the DGT binding phases and modest lateral within-gel diffusion. (ii) Direct gel contact with Cu metal grids enabled quantitative comparison of nominal bar/hole dimensions with DGT-derived solute patterns, demonstrating that features down to ~25µm are detectable under optimal contact and laser ablation conditions. (iii) Application to printed circuit boards confirmed the method's ability to reproduce sub-mm Cu features on technologically relevant materials. Across experiments, gel-phase lateral diffusion and imperfect gel-sample contact were the dominant factors limiting spatial accuracy. These results define the practical lateral resolution of DGT LA-ICP-MS and provide guidance for designing and interpreting high-resolution solute imaging experiments in environmental and materials science.

Tire wear particles (TWPs) are generated by mechanical abrasion of tires on road surfaces and represent a significant source of microplastic pollution, contributing an estimated 30-50% of total microplastic emissions in Europe. Due to their persistence and limited biodegradability, TWPs accumulate in terrestrial, aquatic, and atmospheric environments. However, their detection and quantification remain challenging: carbon black hampers FTIR analysis, while pyrolysis-GC-MS yields only bulk mass data without information about particle abundance or size distribution. We present a novel approach to address this gap using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) combined with elemental fingerprinting and machine learning. We apply this method to zebrafish gut tissue to differentiate TWPs from biological tissue, paraffin-embedded material, and other naturally occurring particles. A random forest model trained on multielement signatures enables pixelwise classification of imaging data recorded with 7-μm lateral resolution despite the complexity of both TWP and biological matrices. Our results demonstrate the potential of LA-ICP-MS elemental imaging as a sensitive tool for TWP detection in biological tissue, providing new opportunities for monitoring and ecotoxicological studies.

Arsenopyrite (FeAsS) is an important sulfide that holds gold in orogenic systems. Its arsenic content is often used as a proxy for gold fertility. However, arsenopyrite from the Um Rus gold deposit in Egypt’s Central Eastern Desert shows a complicated gold distribution that makes simple Au-As correlations hard to make. Integrated electron microprobe analysis (EMPA), laser ablation ICP-MS, and principal component analysis (PCA) reveal three unique textural and geochemical domains. Fine-grained arsenopyrite inclusions within pyrite aggregates (28–31 at% As) are devoid of detectable gold; PCA elucidates 84% of their variance through Fe–S versus Co-As substitution (PC1: 61.8%) and Pb-decoupled variability (PC2: 22.2%), suggesting crystallization from a Co-rich, Au-poor fluid. On the other hand, coarse oscillatory-zoned arsenopyrite can hold up to 6154 ppm of invisible gold. This is because of a moderate Au-As substitution (R = 0.41063, p = 0.08074) that was overprinted by a separate Au-Ag-Sb-Te hydrothermal pulse (Au–Ag: R = 0.97762; Au–Sb: R = 0.97608). PCA finds four parts (72.8% variance): Ag-Cu-As associations (PC1: 25.1%), Te versus Bi-Au signatures (PC2: 17.8%), Fe–S stoichiometry (PC3: 17.1%), and an Au versus Pb-decoupled event (PC4: 12.9%). This shows that minerals formed in more than one stage. Irregular As-rich overgrowths, containing ≤950 ppm gold and lacking significant Au–As correlation (R = −0.14011, p = 0.56726), show PCA (74.3% variance) that highlights S-As contrasts (PC1: 25.2%), Co-Ni enrichment (PC2: 18.8%), Cu-Fe-Ni associations (PC3: 16.2%), and a late Au-decoupled event (PC4: 14.2%), indicating barren recrystallization. These results show that just adding arsenic is not a good way to tell if gold is fertile. The highest amounts of invisible gold, on the other hand, are found in oscillatory-zoned domains with Ag-Sb-Te signatures. This research highlights the importance of combining PCA, geochemistry, and microtextures to differentiate auriferous from barren arsenopyrite, thereby enhancing exploration methodologies for structurally intricate orogenic gold systems.

The discovery of altered rock−type gold orebodies in southeastern Guizhou (southwestern Jiangnan orogen) highlights the region’s significance as a major gold province. However, the timing and the ore-forming processes remain poorly constrained, hindering a comprehensive understanding of gold metallogenic patterns. The Kengtou gold deposit (>15 tons Au) comprises both quartz vein−type and altered rock−type orebodies. Two types of hydrothermal monazite (Mnz1, Mnz2) were identified in this study. Mnz1, associated with pre-ore ankerite (Ank1) and rutile, occurs within unmineralized metamorphic rocks. In contrast, Mnz2 is spatially associated with auriferous sulfides within gold orebodies. Trace-element analyses show that Mnz1 has significantly higher total rare earth element (ΣREE) concentrations (430,658−583,738 ppm, mean = 565,224 ppm) than Mnz2 (67,779−172,804 ppm, mean = 137,558 ppm), although both exhibit similar hydrothermal-type chondrite-normalized REE distribution patterns. Laser ablation−inductively coupled plasma−mass spectrometry (LA-ICP-MS) U-Pb dating yielded lower-intercept ages of 443 ± 16 Ma (Mnz1) and 410 ± 13 Ma (Mnz2). These ages constrain two distinct hydrothermal episodes: The earlier episode (ca. 443 Ma) represents a pre-ore stage related to Caledonian regional greenschist-facies metamorphism that triggered widespread sericitization, while the later episode (ca. 410 Ma) marks the main gold mineralization stage during late Caledonian extension, where fluid-rock interaction led to the precipitation of gold-bearing pyrite. Overall, we propose that the recognition of two episodes of Caledonian hydrothermal activity has implications for district-scale gold exploration in the southwestern margin of the Jiangnan orogen.

Abstract. Calcite has been shown to incorporate trivalent actinides into its crystal lattice, highlighting its potential to contribute to radionuclide retention processes in the environment. Earlier studies on calcite's elemental uptake were conducted under controlled laboratory conditions, which do not fully capture the complexities of natural environments. To gain a deeper understanding of calcite's uptake capacity under natural conditions, a sample from the Wenzel ore mine, Germany, was analyzed, originating from a calcite vein that formed under conditions relevant to deep geological-waste repositories. The chemical analogy between rare earth elements (REEs) and trivalent actinides helps to evaluate the retention potential and incorporation mechanisms of trivalent radionuclides. A micro-X-ray fluorescence (µXRF) element map revealed that the investigated calcite consists of an euhedral crystal core exhibiting sector zoning, characterized by trace element heterogeneity across coevally grown crystal faces. High-resolution laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) further refined and quantified the elemental distribution, revealing preferential incorporation of specific elements, particularly REEs, within one sector of the calcite. Remarkably, this sector showed REE concentrations over 200 times higher than those in the depleted sector, indicating a significant potential for the retention of trivalent actinides. Furthermore, the data indicate that charge equilibration of incorporated trivalent cations occurs via two processes: coupled substitution with monovalent cations and vacancies in the crystal structure. Overall, these results demonstrate that sector-zoned calcite formed under repository-relevant conditions can maintain high retention potential for trivalent actinides, even in environments depleted in monovalent cations.

Nanoparticles, due to their unique size-dependent properties, distinct from those of bulk materials, have become a rapidly developing and intensively studied area of chemistry. These properties include the ability to catalyse chemical reactions, reduced melting temperatures, and distinctive optical characteristics. In this paper, we investigate these features in bimetallic Ag@Ni core-shell nanoparticles of varying composition. The nanoparticles were synthesised via a solvothermal method using silver nitrate and nickel(ii) acetylacetonate in a mixture of oleylamine and octadec-1-ene as solvents. Characterisation was carried out using a series of spectroscopic and microscopic methods. Catalytic activity and surface processes leading to the production and release of carbon dioxide were examined using Knudsen effusion mass spectrometry (KEMS). The highest catalytic activity was noted for Ag-Ni nanoparticles containing approximately 30-50 at% silver. The catalytic process is accompanied by the formation of organometallic compounds, which were detected by X-ray photoelectron spectroscopy (XPS) and laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS). Thermal stability during heating was evaluated by differential scanning calorimetry (DSC), and a melting point depression of approximately 10 °C was observed for all studied samples. The paper is a part of a broader study of Ni-based bimetallic nanoparticles, their thermal stability and catalytic activity.

Integrated laser ablation and computed tomography: detecting the chemical footprint of microplastics and reconstructing 3D biological tissues.

High-throughput identification of geographical origins of rubies using hyperspectral visible and fluorescence spectroscopy.

Transition metals, such as iron, support vital metabolic and signaling functions in immune cells. Cellular iron concentrations are tightly controlled. In T cells, both iron deficiency and iron overload have been linked to immune dysfunction. Homeostatic iron concentrations in T cells, and changes that occur during T cell activation, remain poorly understood due to difficulty of accurately measuring iron content in single cells, especially in small cells. Here, we describe the use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to accurately quantify the total amount of endogenous iron in individual primary human T cells. Our technique allows for targeted selection of single cells and reproducible quantification of iron at femtogram level. Our findings reveal that iron levels in resting T cells were similar across human donors. In contrast, T cell activation leads to diverse patterns between individual cells and donors, indicating specialized needs during differentiation.

The exsolution mechanism of magmatic fluids and their metal migration capacity: example from Huanaote Pb-Zn-polymetallic deposit in Inner Mongolia, China

Droplet-based laser ablation ICP-MS for direct elemental screening of oils with minimal sample preparation.

Subcellular capillary sampling coupled to laser ablation – Inductively coupled plasma – Mass spectrometry (LA-ICP-MS) allows targeted analysis of thallium in a radiopharmaceutical model

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a widely used quantitative technique. However, conventional calibration approaches that depend on internal standards, external reference materials, and linear regression are subject to practical limitations. To address these challenges, we present LA-TReQNet, an end-to-end deep learning framework, that enables fully automated quantitative calibration in LA-ICP-MS. A CNN-LSTM architecture was trained on a data set of 221,364 labeled mass spectra from 5676 samples. We demonstrate that preprocessing of mass spectrometry data substantially impacts model performance and propose an optimized strategy incorporating power transformer-based standardization and data set grouping. By training on extensive multielement data sets, the deep learning model captures complex empirical relationships, thus establishing for the first time a standard-free calibration approach. The optimized LA-TReQNet model accurately quantified 39 elements in three RMs (BCR-2G, BHVO-2G, and BIR-1G) from independent laboratories, confirming its robustness to data source variations. When applied to a broader set of RMs, LA-TReQNet achieved deviations of 0.2% ± 5.8% (SD, n = 198) for major elements and -0.9% ± 9.2% (SD, n = 898) for trace elements relative to certified reference values. The results confirm that deep learning-based elemental quantification achieves accuracy on par with conventional approaches while eliminating the reliance on internal or external standards, thus significantly expanding the applicability of LA-ICP-MS to complex and diverse samples. Moreover, LA-TReQNet eliminates data quality fluctuations from researcher experience differences in traditional handling, improving both processing efficiency and result stability.

Enhancing the absorption efficiency of fertilizers plays an extremely crucial role in agricultural production. Here, we present a novel metallic nanofertilizer with a core-shell structure named Au@mZnO-mSiO2 for the sustained release of Zn in plants. Detection with ICP-MS found that the content of Zn in the cucumber incubated with Au@mZnO-mSiO2 exhibited a significantly higher content of Zn than the blank. The results of imaging with laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) showed significant increases in Zn, Cu, and P in cucumber leaves incubated with Au@mZnO-mSiO2. The cucumber incubated with Au@mZnO-mSiO2 had longer roots, thicker stems, and enlarged leaves, which indicated that Au@mZnO-mSiO2 showed favorable effects on the growth of the cucumber. This work has meaningful implications for nanofertilizers in the advancement of sustainable agricultural production and also provides a novel tracking method for the study of nanoparticles in plant translocation pathways simultaneously, with their quantitation by ICP-MS and imaging by LA-ICP-MS.

Abstract. Gem-quality corundum varieties of ruby and sapphire are one of the most valuable and desired gemstones. Due to their rarity, new methods of synthesis and treatment were developed over the last decades, complicating the reliable identification between natural, treated, and synthetic specimens. Among the geochemical methods used for identification, trace element analysis using laser ablation inductively coupled plasma mass-spectrometry (LA-ICP-MS) is widely applied. However, solely relying on LA-ICP-MS trace element analysis for differentiation between natural and synthetic corundum origins, especially when grown by the hydrothermal method, can potentially lead to misidentifications. To further enable geochemical tracing of corundum, this study explores secondary ion mass spectrometry (SIMS) oxygen isotope analysis. High-spatial-resolution SIMS δ18O analysis of hydrothermally synthesized corundum yielded values between -7.84±0.13 ‰ and -14.54±0.13 ‰ (relative to Vienna standard mean ocean water, VSMOW; 1 standard error) that are atypical for natural corundum. For flame fusion corundum, SIMS δ18O analyses are in the range of -6.73±0.13 ‰ to -17.46±0.13 ‰ for sapphires of blue, yellow, and orange colour and +28.51±0.11 ‰ to +30.47±0.10 ‰ for ruby, which, in both cases, are again atypical for natural corundum. SIMS δ18O analysis of corundum thus has strong potential to distinguish synthetic and natural corundum.