Journal of Analytical Atomic Spectrometry最新文献

{"title":"The influence of cone orifice diameter on ion transmission in solution and laser ablation ICP-MS†","authors":"Claire A. Richards, Matthew A. Turner and Amy J. Managh","doi":"10.1039/D5JA00046G","DOIUrl":"https://doi.org/10.1039/D5JA00046G","url":null,"abstract":"<p >Optimal sampler and skimmer cone orifice diameter has been well developed for solution based inductively coupled plasma-mass spectrometry (ICP-MS) but is not fully understood for modern laser ablation (LA) systems. This research investigates the impact of various cone orifice sets and the effect they have on ICP-MS sensitivity using solution mode and whilst using a low-dispersion LA system. A wide range of elements between the masses <small>⁷</small>Li and <small>²³⁸</small>U and their oxides have been measured <em>via</em> solution nebulisation as well as NIST 610 glass reference material and multi-elemental gelatine microdroplets <em>via</em> laser ablation. For multi-elemental micro droplets, 7 out of 11 elements analysed showed a statistically significant increase in sensitivity when a reduction of cone orifice size of 0.1 mm was used, compared to the standard cone orifice size. Similarly, for the ablation of NIST 610, 7 out of 11 elements displayed a statistically higher sensitivity with a 0.1 mm reduced orifice size. This analysis has confirmed suitability of standard cone sets for nebulisation of homogeneous solutions whilst suggesting a slight reduction in cone orifice diameter improves ion transmission through the cones towards the mass spectrometer by up to 272% (NIST 610) or 124% (multi-elemental droplets) for LA-ICP-MS.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1726-1732"},"PeriodicalIF":3.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ja/d5ja00046g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two new barite reference materials for SIMS sulfur isotope analysis: evaluation of the crystallographic orientation effect and homogeneity†","authors":"Lan-Lan Tian, Xiao-Lei Wang, Yue Guan, Wen-Li Xie, Kexin Xu, Feng-Tai Tong, Tao Yang and Yong-Bo Peng","doi":"10.1039/D5JA00123D","DOIUrl":"https://doi.org/10.1039/D5JA00123D","url":null,"abstract":"<p >Barite serves as a crucial archive for reconstructing sulfur cycling evolution throughout geologic history. Microscale space variations in sulfur isotope compositions (<em>δ</em><small>³⁴</small>S) of barite provide valuable insights into the barite precipitation process. While secondary ion mass spectrometry (SIMS) microanalysis has emerged as a powerful tool for such investigations, the availability of high quality reference materials remains a fundamental requirement for accurate measurements. Although several barite reference materials have been developed for SIMS analysis, the potential influence of crystallographic orientation on sulfur isotope measurements has not been systematically evaluated. Moreover, the development of more <em>in situ</em> barite reference materials with diverse sulfur isotopic compositions would greatly facilitate cross-laboratory data comparison. In this study, we conducted a comprehensive investigation of the crystallographic orientation effect by combining electron backscatter diffraction (EBSD) and SIMS analyses. Our results demonstrate that crystallographic orientation does not produce significant analytical bias in SIMS barite sulfur isotope measurements at current levels of analytical precision. Furthermore, we present two new well-characterized potential reference materials NJU-Ba-1 and NJU-Ba-2 barite specifically developed for microbeam sulfur isotope analysis. Detailed characterization of texture and major element composition confirms the absence of internal zoning in ground fragments from both barite specimens. These two reference materials establish an extended <em>δ</em><small>³⁴</small>S<small>_V-CDT</small> calibration range for microanalytical studies, with certified values of 6.18 ± 0.34‰ (2SD, <em>N</em> = 17) and 14.16 ± 0.26‰ (2SD, <em>N</em> = 9) for NJU-Ba-1 and NJU-Ba-2 respectively, as determined by gas-source isotope ratio mass spectrometry (GS-IRMS). Extensive SIMS analyses revealed exceptional homogeneity at both inter- and intra-unit scales, with <em>δ</em><small>³⁴</small>S variations of 0.36‰ (2SD, <em>N</em> = 328) for NJU-Ba-1 and 0.45‰ (2SD, <em>N</em> = 343) for NJU-Ba-2. These performance characteristics indicate that NJU-Ba-1 and NJU-Ba-2 are promising candidates as reference materials for high-precision microanalytical studies of barite sulfur isotopes.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1845-1851"},"PeriodicalIF":3.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the non-universality of distance metrics in laser-induced breakdown spectroscopy†","authors":"J. Vrábel, E. Képeš, P. Nedělník, A. Záděra, P. Pořízka and J. Kaiser","doi":"10.1039/D4JA00377B","DOIUrl":"https://doi.org/10.1039/D4JA00377B","url":null,"abstract":"<p >The ability to measure similarity between high-dimensional spectra is crucial for numerous data processing tasks in spectroscopy. Many popular machine learning algorithms depend on, or directly implement, a form of similarity or distance metric. Despite its profound influence on algorithm performance and sensitivity to signal fluctuations, the selection of an appropriate metric remains often neglected within the spectroscopic community. This work aims to shed light on the metric selection process in Laser-Induced Breakdown Spectroscopy (LIBS) and study consequences for data analysis and analytical performance in selected applications. We studied six relevant distance metrics: Euclidean, Manhattan, cosine, Siamese, fractional, and mutual information. We assessed their response to changes in sample composition, additive noise, and signal intensity. Our results show specific vulnerabilities of commonly used metrics, such as the Euclidean metric's high sensitivity to additive noise and the cosine metric's sensitivity to spectral shifts. The Siamese metric stood out in the majority of studied cases and outperformed others in a direct comparison within the spectra classification task. This work provides basic guidelines for selecting metrics in various contexts. The methodology is general and can be directly extended to other spectroscopic techniques that possess comparable data properties.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 6","pages":" 1552-1565"},"PeriodicalIF":3.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ja/d4ja00377b?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"M332 and MK617: two new potential pyrite reference materials for in situ sulfur isotope analysis†","authors":"Jia-Long Hao, Ruo-Long Chi, Zheng-Jie Qiu, Guo-Qiang Tang, Ze-Xian Cui, Lian-Jun Feng, Hao Yan, Qiao-Qiao Zhu, Ping Gao and Wei Yang","doi":"10.1039/D5JA00089K","DOIUrl":"https://doi.org/10.1039/D5JA00089K","url":null,"abstract":"<p >With the growing use of <em>in situ</em> techniques such as Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS), Large Geometry Secondary Ion Mass Spectrometry (LG-SIMS), and NanoSIMS in sulfur isotope studies, new sulfide reference materials (RMs) are needed to meet increasing analytical demands and ensure accuracy. This study introduces two new natural pyrite RMs, M332 and MK617, characterized for <em>in situ</em> sulfur isotope analysis using LA-MC-ICP-MS, LG-SIMS, and NanoSIMS. Their sulfur isotope homogeneity was rigorously confirmed by <em>in situ</em> analysis, which agree with isotope Ratio Mass Spectrometry (IRMS) bulk analyses within analytical uncertainty, validating their reliability as RMs. The recommended <em>δ</em><small>³⁴</small>S values, determined by IRMS, are 24.96 ± 0.22‰ (2 SD, <em>n</em> = 10) for M332 and −4.43 ± 0.21‰ (2 SD, <em>n</em> = 12) for MK617. Additional SIMS analyses yielded <em>δ</em><small>³³</small>S values of 12.89 ± 0.60‰ (2SD, <em>n</em> = 104) for M332 and −2.23 ± 0.35‰ (2SD, <em>n</em> = 120) for MK617, further supporting their isotopic consistency. In conclusion, M332 and MK617 exhibit good isotopic homogeneity and span a wide surfur isotope range, making them highly suitable reference materials for calibrating <em>in situ</em> sulfur isotope studies across diverse geochemical and biological process applications.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1645-1651"},"PeriodicalIF":3.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ja/d5ja00089k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How are negative ions in an ICPMS formed?†","authors":"Andrea Raab, Hamid Badiei and Jörg Feldmann","doi":"10.1039/D4JA00433G","DOIUrl":"https://doi.org/10.1039/D4JA00433G","url":null,"abstract":"<p >Interest in the determination of halogen containing compounds, especially fluorine, has increased exponentially over the last decade. Nevertheless, the development of instruments and methodologies for direct determination of fluorine has not yet reached a state where this is possible in routine laboratories. We revisited negative ion ICPMS using a modern commercial ICPMS with few modifications to the detector and ion optics to test whether fluorine detection with reasonable sensitivity would be possible with such an instrument. The aim of the study was to identify the processes behind the production of negative ions in a commercially available ICPMS. Using all halogens as diagnostic tools, many parameters such as water content, forward power, gas flows, and ion optics parameters were studied. Negatively charged bromine, chlorine and fluorine ions are generated in the interface, not the plasma, and their sensitivities mainly depend on the atomic radius (as a proxy for collision cross-section) and not on electron affinity. This knowledge is important for potentially building an instrument capable, among other elements, of determining fluorine with the capability to address the needs in environmental and medical science.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1689-1699"},"PeriodicalIF":3.1,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ja/d4ja00433g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sequential separation of multi-isotopes from limited samples through a two-step column chromatography approach†","authors":"Lei Li, Fang Liu, Qingyao Peng, Zhaofeng Zhang, Xin Li and Yajun An","doi":"10.1039/D5JA00120J","DOIUrl":"https://doi.org/10.1039/D5JA00120J","url":null,"abstract":"<p >Calcium (Ca), strontium (Sr), barium (Ba), cerium (Ce), and neodymium (Nd) isotopes have broad applications in the Earth and planetary sciences. Usually, only one specific element is separated using an individual separation procedure, which requires substantial sample quantities. However, this poses challenges for limited samples, such as extraterrestrial materials (meteorites or returned samples). Herein, we developed a two-step, three-column method to separate multi-isotopes—Ca, Sr, Ba, Ce, and Nd—from a single geological sample solution. In the first step, AG 50W-X8 (200–400 mesh) resin was used to separate the sample solution into two sub-solutions: (1) major elements + Sr and (2) rare-earth elements (REE) + Ba. In the second step, Ca and Sr were sequentially separated from the former solution using AG 50W-X12 (200–400 mesh) resin, while Ba, Ce and Nd were sequentially separated from the latter solution using DGA (50–100 μm) resin. The recovered yields of all the target elements were over 99.5%, with low whole-procedure blanks. To verify the reliability of this analytical technique, five international rock standards, including NOD-A-1 (manganese nodules), AGV-2 (andesite), BHVO-2 (basalt), GSP-2 (granodiorite), COQ-1 (carbonatite), and two simulated lunar soil samples (CUG-1A and CUG-1B), were analyzed. Results show that only 1–2 mg of samples is sufficient to achieve simultaneous and accurate measurements of Ca, Sr, Ba, Ce and Nd, offering comprehensive isotope data with minimal sample consumption. This approach will be particularly valuable for studying limited and precious samples, thus providing important technological support for the development of the earth sciences and planetary sciences.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1767-1775"},"PeriodicalIF":3.1,"publicationDate":"2025-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highly resolved detection of deuterium at atmospheric pressure","authors":"Ali M. Alamri, M. A. Wakil, Philip Kwong and Zeyad T. Alwahabi","doi":"10.1039/D5JA00051C","DOIUrl":"https://doi.org/10.1039/D5JA00051C","url":null,"abstract":"<p >A highly resolved analytical method suitable for the analysis of emission spectra from hydrogen atoms and deuterium atoms is presented. The method is based on microwave-assisted laser-induced breakdown spectroscopy and is applicable to liquid phase analytes under atmospheric conditions. Emissions from excited hydrogen (and deuterium) atoms and OH (and OD) radicals were collected and quantitatively analysed using two types of diffraction gratings. The method takes advantage of the reduced electron density in microwave-assisted laser-induced breakdown spectroscopy plasma, which produces a narrow atomic emission linewidth. This feature permits highly resolved spectra of 0.2 volume fraction of deuterium in the presence of 0.8 volume fraction of hydrogen. Using a 2400 lines per mm diffraction grating and D<small>_α</small> emission, the MW-LIBS deuterium limit of detection and limit of quantification were 0.4% and 1.3%, respectively. Using a 2400 lines per mm diffraction grating and OD radicals' emission, the MW-LIBS limit of detection and limit of quantification were 0.85% and 2.8%, respectively. The OD rotational branches were resolved even better using a 3600 lines per mm diffraction grating, yielding a three-fold improvement in the limit of detection. The detection of hydrogen atoms and deuterium atoms based on MW-LIBS is very beneficial due to its excellent repeatability, selectivity, and applicability under atmospheric pressure in ambient air.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1821-1832"},"PeriodicalIF":3.1,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous determination of Cl, Br and I by aerosol-assisted PVG-ICP-MS†","authors":"Gustavo R. Bitencourt, Paola A. Mello, Patricia Grinberg and Ralph E. Sturgeon","doi":"10.1039/D5JA00079C","DOIUrl":"https://doi.org/10.1039/D5JA00079C","url":null,"abstract":"<p >Simultaneous determination of Cl, Br and I by aerosol-assisted photochemical vapor generation (PVG) with detection by inductively coupled plasma mass spectrometry (ICP-MS) was investigated. The photoreactor comprised a modified cyclonic spray chamber fitted with a central UV source for irradiation of pneumatically generated sample aerosol. A systematic evaluation of variables was conducted, focusing on achieving compromise optimal PVG conditions suitable for simultaneous Cl, Br and I generation. By using a sample medium comprising 1% v/v acetic acid containing 20 mg L<small>⁻¹</small> Cu<small>²⁺</small> as mediator, the signal intensities for Cl, Br and I were enhanced by 3-, 40- and 30-fold, respectively, compared to those obtained by conventional pneumatic nebulization (PN). LODs of 4.2 ng mL<small>⁻¹</small>, 6.3 pg mL<small>⁻¹</small> and 1.9 pg mL<small>⁻¹</small> were achieved for Cl, Br and I, respectively, with corresponding estimated overall PVG efficiencies of 10, 99 and 90%. In addition to the halides, halate species, <em>i.e.</em>, ClO<small>₃</small><small>⁻</small>, BrO<small>₃</small><small>⁻</small> and IO<small>₃</small><small>⁻</small>, were also examined, but poor PVG efficiencies (lower than 5%) were encountered. However, addition of 20 mg L<small>⁻¹</small> SO<small>₃</small><small>²⁻</small> to the generation medium enhanced response for BrO<small>₃</small><small>⁻</small> and IO<small>₃</small><small>⁻</small>, achieving similar values to those obtained from Br<small>⁻</small> and I<small>⁻</small>. The impact of NO<small>₃</small><small>⁻</small> (as both HNO<small>₃</small> and KNO<small>₃</small>) and NH<small>₄</small>OH on generation efficiencies was also investigated. The method was tested by the successful simultaneous determination of total Cl, Br and I in a variety of certified reference materials (CRMs) digested by microwave-induced combustion (MIC), including NRCC DORM-5 – Fish Protein, NIST SRM 1632c – Coal, NIST SRM 1515 – Apple Leaves and NIST SRM 1549 – Non-fat Milk Powder.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1754-1766"},"PeriodicalIF":3.1,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ja/d5ja00079c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TrCSL: a transferred CNN-SE-LSTM model for high-accuracy quantitative analysis of laser-induced breakdown spectroscopy with small samples†","authors":"Shengjie Ma, Shilong Xu, Congyuan Pan, Jiajie Fang, Fei Han, Yuhao Xia, Wanying Ding, Youlong Chen and Yihua Hu","doi":"10.1039/D4JA00459K","DOIUrl":"https://doi.org/10.1039/D4JA00459K","url":null,"abstract":"<p >When utilizing the laser-induced breakdown spectroscopy (LIBS) technology for high-precision quantitative analysis, a substantial number of samples are typically required to construct an accurate prediction model. However, in many practical applications, obtaining sufficient samples often faces challenges. The scarcity of samples not only reduces the reliability of experiments but also limits the potential and flexibility of LIBS technology in a broader range of applications. In this study, we introduced a transferred convolutional neural network-squeeze and excitation-long short-term memory (TrCSL) model, aimed at achieving high-precision quantitative analysis even with small samples. The TrCSL model combines the strengths of transfer learning, convolutional neural networks (CNN), squeeze and excitation (SE) block mechanisms, and long short-term memory (LSTM) networks to enhance feature extraction and learning capabilities. We trained on 100 sets of steel slag samples to obtain the pre-training model, which was then transferred to the small samples and underwent fine-tuning of its parameters. Compared to the traditional partial least squares regression (PLSR) and support vector regression (SVR) algorithms, the TrCSL model shows an improvement of about 0.4 in the <em>R</em><small>²</small> value for quantitative analysis results on 20 carbon steel samples. In addition, the experimental results also show that the quantitative analysis accuracy of the TrCSL model on only 20 samples is close to that of traditional PLSR and SVR algorithms on 80 samples. The TrCSL model proposed in this paper possesses enhanced universality and superior prediction accuracy, offering a novel approach to improving LIBS quantitative analysis precision with small samples.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1810-1820"},"PeriodicalIF":3.1,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ja/d4ja00459k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ analysis of titanium isotope ratios in stardust using LA-CC-MC-ICPMS/MS†","authors":"Kathryn M. M. Shaw, Markus Pfeifer, Benjamin L. L. Coath, Jamie Lewis, Dan Bevan, Christopher D. Coath and Tim Elliott","doi":"10.1039/D5JA00068H","DOIUrl":"10.1039/D5JA00068H","url":null,"abstract":"<p >Presolar grains are nanometre-scale dust grains that exhibit large isotope excursions that illustrate the stellar isotopic input into the Solar System. Further, it is thought that they were differentially incorporated into meteorite parent bodies and thus can be used to trace planetary genetics and construction. <em>In situ</em> mapping of the distribution of presolar grains in the matrix of primitive meteorites therefore provides a key means to achieve this goal. However, <em>in situ</em> methods complicate isotopic measurements, such as those of Ti, due to their large isobaric interferences. To enable such measurements a prototype a collision cell, multicollector inductively-coupled plasma mass spectrometer with a pre-cell mass filter (CC-MC-ICPMS/MS) was developed and called Proteus. In this study we show that, when coupled to a laser ablation system, Proteus has the capability to measure, <em>in situ</em>, large Ti isotope excursions such as those expected in presolar grains (&gt;200‰). Within the collision cell we introduced O<small>₂</small> gas and react Ti<small>⁺</small> to TiO<small>⁺</small> and perform the multi-collector isotope ratio measurement on the TiO<small>⁺</small> species. The presence of isobaric interferences from Ca<small>⁺</small>, V<small>⁺</small>, and Cr<small>⁺</small> are greatly reduced due to their lower ion reaction efficiency with O<small>₂</small> gas. The measurement of TiO<small>⁺</small> using the pre-cell mass filter ensures that these ions are measured in a cleared region of the mass-spectrum where a Ni<small>⁺</small>, Cu<small>⁺</small>, and Zn<small>⁺</small> ions would otherwise be present as interferences. Using this technique, complex rock samples with high Ca/Ti and Cr/Ti, for example BIR-1G, give the same mass-independent isotopic Ti ratios as essentially pure Ti-minerals, <em>e.g.</em> brookite. By reducing isobaric interferences from <em>in situ</em> measurements we can detect the large isotopic excursions in presolar grains without the added impediment of non-solar interference corrections for isobaric interferences.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 6","pages":" 1566-1579"},"PeriodicalIF":3.1,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12097295/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}