Ana Rua Ibarz

@article{NAKADI2025127920,

title = {LAMIS in the gas phase: A new approach for obtaining Ca elemental and isotopic information via CaF molecule formation},

author = {Flávio V. Nakadi and Alicia Garcia-Garcia and Ana Rua-Ibarz and Martín Resano},

url = {https://www.sciencedirect.com/science/article/pii/S0039914025004102},

doi = {https://doi.org/10.1016/j.talanta.2025.127920},

issn = {0039-9140},

year  = {2025},

date = {2025-01-01},

urldate = {2025-01-01},

journal = {Talanta},

volume = {292},

pages = {127920},

abstract = {This work introduces a novel method for generating the calcium monofluoride (CaF) diatomic molecule by adding the molecule-forming reagent in the gaseous phase (a methyl fluoride-argon mixture), in order to perform laser-induced breakdown spectroscopy (LIBS) and laser ablation molecular isotopic spectrometry (LAMIS) measurements. By optimizing the instrumental parameters, CaF molecule formation was successfully achieved within the plasma plume, upon ablation of dried liquid samples. The isotopic shift for the X2Σ→A2Π (0,1) CaF vibronic transition at 583.0 nm was calculated to be 292.3 pm. The method proved capable of providing quantitative information for determining calcium concentrations in real samples, such as tap water and skimmed milk, using internal standardization (with Sr as internal standard; limit of detection, LOD, 20 mg L−1) and isotope dilution (which can be applied from 400 mg L−1on), respectively. Partial least squares regression (PLS) analysis was employed to enhance the quality of the isotopic data. The Ca concentration found in the tap water was 47 ± 16 mg L−1 (reference flame atomic absorption spectrometry, FAAS, value: 59 ± 0.2 mg L−1), and 1100 ± 140 mg L−1 for the skimmed milk (reference FAAS value: 1240 ± 120 mg L−1). No significant difference between LIBS and FAAS results could be established using a t-test at the 95% confidence level. Overall, this novel approach allows for the determination of calcium in terms of both the elemental concentration and the isotopic composition, thus broadening the applicability of LIBS (e.g., for tracer experiments, besides the already mentioned application of isotope dilution).},

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pubstate = {published},

tppubtype = {article}

}

@article{BAZO2025344694,

title = {Improving detection and figures of merit in single-particle inductively coupled plasma-mass spectrometry via transient event heights},

author = {Antonio Bazo and Lorién López-Villellas and Matilde Mataloni and Eduardo Bolea-Fernandez and Ana Rua-Ibarz and Marco Grotti and Maite Aramendía and Martín Resano},

url = {https://www.sciencedirect.com/science/article/pii/S0003267025010888},

doi = {https://doi.org/10.1016/j.aca.2025.344694},

issn = {0003-2670},

year  = {2025},

date = {2025-01-01},

urldate = {2025-01-01},

journal = {Analytica Chimica Acta},

volume = {1378},

pages = {344694},

abstract = {Background 

Single-particle inductively coupled plasma-mass spectrometry (SP-ICP-MS) is a powerful method for characterizing micro- and nanoparticulate materials. The technique primarily relies on the linear relationship between the integrated intensities of individual events (peak areas) and the analyte mass, though transit times (peak widths) have also been used for quantitative purposes. This work (1) evaluates the potential of using peak heights as analytical signals in SP-ICP-MS, (2) introduces a new method for determining peak heights, and (3) explores scenarios in which peak height offers added value over the commonly used SP-ICP-MS signals. 

Results 

A new method was proposed to estimate peak height values in SP-ICP-MS accurately. The cumulative intensity across consecutive dwell times was modeled using a third-degree polynomial, from which the adjusted peak height was derived. This approach reduces the uncertainty associated with using raw maximum intensity values, yielding NP distributions comparable to those obtained via integrated intensities. The effect of dwell time on peak height was also evaluated. An optimal range (50 μs–200 μs) was identified, where a linear relationship was observed between the peak height and the square of the NP diameter. Within this range, peak height showed the lowest bias when characterizing smaller NPs, indicating the potential to improve the limit of quantification (LoQ). Additionally, peak heights proved helpful in determining the limit of detection (LoD) and setting appropriate threshold values for data processing, thereby helping to flag incorrect resultsand addressing a challenge in SP-ICP-MS analysis. 

Significance 

This is the first study to evaluate peak height as an analytical signal in SP-ICP-MS. The results highlight its advantages in specific applications, such as sizing NPs near the LoD, and in supporting the more reliable use of other signals, such as peak areas, by helping to identify incorrect threshold selection that could lead to biased distributions. Finally, monitoring peak heights allows for a more realistic and assumption-free determination of the LoD.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{D5JA00253B,

title = {A novel particle mass calibration strategy for the quantification of AuNPs in single cancer cells via laser ablation ICP-mass spectrometry. A case study},

author = {Antonio Bazo and Eduardo Bolea-Fernandez and Kharmen Billimoria and Ana Rua-Ibarz and Maite Aramendía and Paula Menero-Valdés and Jack Morley and Sara Neves and Armando Sánchez-Cachero and Heidi Goenaga-Infante and Martín Resano},

url = {http://dx.doi.org/10.1039/D5JA00253B},

doi = {10.1039/D5JA00253B},

year  = {2025},

date = {2025-01-01},

urldate = {2025-01-01},

journal = {J. Anal. At. Spectrom.},

volume = {40},

pages = {2673-2681},

publisher = {The Royal Society of Chemistry},

abstract = {Laser ablation ICP-mass spectrometry (LA-ICP-MS) has developed as a powerful tool for elemental quantitative analysis of individual cells, assuring that the content of each cell is analyzed individually. However, this technique is still limited by the difficulties associated with calibration using solid standards. This work proposes a particle mass calibration strategy that is independent of both the properties and thickness of the gelatin films used for calibration, overcoming a significant drawback of previously established methods. The fundamental principle of this strategy relies on the individual ablation of nanoparticles (NPs) of well-characterized size that are embedded in the films, so that their mass can be directly used for calibration without the need to calculate their exact concentration within the gelatin. The performance of the newly developed method was compared to that of the previously reported approaches (ionic and particle number calibration) in terms of linearity and homogeneity between different films prepared from the same gelatin solution. As a case study, the three calibration strategies were used for the quantitative analysis of HeLa cancer cells exposed to AuNPs. In parallel, in-suspension single-cell (SC) ICP-MS Au data were obtained and used as reference for comparison with the three LA-SC-ICP-MS strategies. The results obtained with the novel particle mass approach demonstrated better accuracy and repeatability over three different working sessions, addressing key limitations and providing a robust and reliable method for quantitative LA-SC-ICP-MS analysis. The particle mass method holds promise for quantitative LA-ICP-MS analysis of samples beyond NP-exposed cells, such as biological tissues.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{D3JA00271C,

title = {A comparison of calibration strategies for quantitative laser ablation ICP-mass spectrometry (LA-ICP-MS) analysis of fused catalyst samples},

author = {Ana Rua-Ibarz and Thibaut Van Acker and Eduardo Bolea-Fernandez and Marina Boccongelli and Frank Vanhaecke},

url = {http://dx.doi.org/10.1039/D3JA00271C},

doi = {10.1039/D3JA00271C},

year  = {2024},

date = {2024-01-01},

urldate = {2024-01-01},

journal = {J. Anal. At. Spectrom.},

volume = {39},

issue = {3},

pages = {888-899},

publisher = {The Royal Society of Chemistry},

abstract = {In the field of petrochemistry, the quantitative determination of trace elements in catalysts is crucial for optimizing various types of processes. Catalyst poisoning, resulting from the presence of contaminants, can lead to decreased performance and efficiency, even when these are present at trace level only. Inductively coupled plasma-mass spectrometry (ICP-MS) is a powerful technique for trace elemental analysis, but its application to catalysts is challenging due to their physicochemical characteristics challenging straightforward dissolution. Laser ablation (LA) coupled to ICP-MS (LA-ICP-MS) has emerged as a valuable approach for direct analysis of solid samples. However, developing an appropriate calibration strategy for reliable quantitative LA-ICP-MS analysis of catalyst samples remains a challenge. In this work, different calibration strategies for quantitative LA-ICP-MS analysis of fused catalyst samples were evaluated. The traditional strategy relied on external calibration against certified reference materials (CRMs) combined with internal standardization and was considered the reference approach. When using this approach, the relative bias with respect to the reference value was found to be <15%. Two novel calibration strategies were introduced and compared: a so-called multi-signal calibration approach and a solution-based calibration approach. The multi-signal calibration strategy involved varying the laser repetition rate (20, 30, 40 and 50 Hz) or laser beam diameter (10, 12, 15 and 20 μm), allowing a calibration curve to be constructed by comparing the analytical signal intensity for a single solid CRM with that for the sample, thus partially overcoming the shortage of CRMs for quantitative LA-ICP-MS analysis. The solution-based calibration approach was used for quantitative multi-element analysis without the need for any solid standard and required only minor hardware modifications to accommodate the introduction of aqueous standard solutions for calibration. Various glass certified reference materials were used for method development, calibration, and validation purposes. Furthermore, two fused alumina catalyst samples (used in the context of petroleum refining processes) were successfully analyzed as a proof-of-concept application. For both the multi-signal (matrix-matched conditions) and the solution-based calibration approaches, the average relative bias between the experimentally determined and certified/reference concentrations varied between −9% and +7%.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{BOLEAFERNANDEZ2024126210,

title = {Development and initial evaluation of a combustion-based sample introduction system for direct isotopic analysis of mercury in solid samples via multi-collector ICP-mass spectrometry},

author = {Eduardo Bolea-Fernandez and Ana Rua-Ibarz and Jorge Alves Anjos and Frank Vanhaecke},

url = {https://www.sciencedirect.com/science/article/pii/S0039914024005897},

doi = {https://doi.org/10.1016/j.talanta.2024.126210},

issn = {0039-9140},

year  = {2024},

date = {2024-01-01},

urldate = {2024-01-01},

journal = {Talanta},

volume = {276},

pages = {126210},

abstract = {High-precision isotopic analysis of mercury (Hg) using multi-collector ICP-mass spectrometry (MC-ICP-MS) is a powerful method for obtaining insight into the sources, pathways and sinks of this toxic metal. Modification of a commercially available mercury analyzer (Teledyne Leeman Labs, Hydra IIc – originally designed for quantification of Hg through sample combustion, collection of the Hg vapor on a gold amalgamator, subsequent controlled release of Hg and detection using cold vapor atomic absorption spectrometry CVAAS) enabled the system to be used for the direct high-precision Hg isotopic analysis of solid samples using MC-ICP-MS – i.e., without previous sample digestion and subsequent dilution. The changes made to the mercury analyzer did not compromise its (simultaneous) use for Hg quantification via CVAAS. The Hg vapor was mixed with a Tl-containing aerosol produced via pneumatic nebulization, creating wet plasma conditions, and enabling the use of Tl as an internal standard for correction of instrumental mass discrimination. Accurate and precise (0.10 ‰ 2SD, δ202Hg},

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pubstate = {published},

tppubtype = {article}

}