Lecture
Improved Workflows for the Production and Metrological Characterisation of LA-ICP-MS Calibration Standards for Quantitative Bioimaging
- at -
- ICM Saal 5
- Type: Lecture
Lecture description
P. Menero-Valdes , K. Billimoria , H. Goenaga-Infante
Recent advances in LA-ICP-MS bioimaging instrumentation have enabled faster acquisition of high-resolution elemental maps; however, quantitative analysis remains limited by the availability of well-characterised and fit-for-purpose calibration materials. In the absence of widely available bio-standards, quantification has often relied on inhouse approaches, restricting comparability across different experiments and time [1]. While automated preparation of calibration standards has recently been explored with promising outcomes [2,3], further methodological development and validation have been identified as required.
In this work, we describe an optimised workflow for the preparation and metrological characterisation of bioprinted gelatin calibration standards that are fit-for-purpose for both tuning of the laser LA-ICPMS parameters and to obtain quantitative bioimaging data across the m/z elemental range. Gelatin matrices were doped with elements of interest in the form of nanoparticles as well as uranium and thorium elemental solutions. Printing parameters were systematically optimised to produce standards with a mean area of 5.9 ± 0.13 mm² and a thickness of 1.99 ± 0.10 µm, accurately measured by ellipsometry.
Elemental homogeneity within a standard (spiked bioprinted gelatin droplet) was assessed by sub-sampling eight regions per standard; variations in average signal intensity were below 5% for all elements. The relatively large size and elemental homogeneity of the standards enable their reusability. This is an important feature as it enables sampling from within the same droplet to monitor instrumental sensitivity during long imaging experiments and across multiple batches. For this purpose, the minimal ablation area which is representative of the overall performance was investigated. Additionally, short-term stability and shipping feasibility, were systematically evaluated to ensure standards are feasible for future wider dissemination to help improve comparability between laboratory measurements.
[1] K. Mervič, M. Šala and S. Theiner, TrAC Trends in Analytical Chemistry, 2024, 175,5,117574
[2] K. Billimoria, Y. A Diaz Fernandez, E. Andresen, I. Sorzabal-Bellido, G. HuelgaSuarez, D. Bartczak, C. Ortiz de Solórzano, U. Resch-Genger, H. Goenaga-Infante,
Metallomics, 2022,14, 12, mfac088
[3] A. Schweikert, S. Theiner, D. Wernitznig, A. Schoeberl, M. Schaier, S. Neumayer, B. K. Keppler, G. Koellensperger, Analytical and Bioanalytical Chemistry, 2022, 414, 485–495.
Recent advances in LA-ICP-MS bioimaging instrumentation have enabled faster acquisition of high-resolution elemental maps; however, quantitative analysis remains limited by the availability of well-characterised and fit-for-purpose calibration materials. In the absence of widely available bio-standards, quantification has often relied on inhouse approaches, restricting comparability across different experiments and time [1]. While automated preparation of calibration standards has recently been explored with promising outcomes [2,3], further methodological development and validation have been identified as required.
In this work, we describe an optimised workflow for the preparation and metrological characterisation of bioprinted gelatin calibration standards that are fit-for-purpose for both tuning of the laser LA-ICPMS parameters and to obtain quantitative bioimaging data across the m/z elemental range. Gelatin matrices were doped with elements of interest in the form of nanoparticles as well as uranium and thorium elemental solutions. Printing parameters were systematically optimised to produce standards with a mean area of 5.9 ± 0.13 mm² and a thickness of 1.99 ± 0.10 µm, accurately measured by ellipsometry.
Elemental homogeneity within a standard (spiked bioprinted gelatin droplet) was assessed by sub-sampling eight regions per standard; variations in average signal intensity were below 5% for all elements. The relatively large size and elemental homogeneity of the standards enable their reusability. This is an important feature as it enables sampling from within the same droplet to monitor instrumental sensitivity during long imaging experiments and across multiple batches. For this purpose, the minimal ablation area which is representative of the overall performance was investigated. Additionally, short-term stability and shipping feasibility, were systematically evaluated to ensure standards are feasible for future wider dissemination to help improve comparability between laboratory measurements.
[1] K. Mervič, M. Šala and S. Theiner, TrAC Trends in Analytical Chemistry, 2024, 175,5,117574
[2] K. Billimoria, Y. A Diaz Fernandez, E. Andresen, I. Sorzabal-Bellido, G. HuelgaSuarez, D. Bartczak, C. Ortiz de Solórzano, U. Resch-Genger, H. Goenaga-Infante,
Metallomics, 2022,14, 12, mfac088
[3] A. Schweikert, S. Theiner, D. Wernitznig, A. Schoeberl, M. Schaier, S. Neumayer, B. K. Keppler, G. Koellensperger, Analytical and Bioanalytical Chemistry, 2022, 414, 485–495.
