Krmpotić Matea, Telkhozhayeva Madina, Tsubery Merav Nadav, Goldenberg-Cohen Nitza, Girshevitz Olga
Division of Experimental Physics, Ruđer Bošković Institute, 10000, Zagreb, Croatia.
Bar-Ilan Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, 5290002, Ramat Gan, Israel.
Talanta. 2025 Apr 1;285:127394. doi: 10.1016/j.talanta.2024.127394. Epub 2024 Dec 15.
The dried matrix spot (DMS) method, initially developed for neonatal blood screening, has gained prevalence in various research fields for its efficiency in handling small sample volumes and its adaptability to diverse analytical techniques. This study presents the results of the first systematic investigation of direct multi-element analysis in DMS of human blood and plasma samples with Particle Induced X-ray Emission (PIXE). Internal standard addition was used to address the issue of DMS heterogeneity and to eliminate the need for determining the sample volume equivalent, allowing a single-spot (single-punch) measurement. The method was tested for linearity, accuracy, precision and limit of detection (LOD) using reference materials. It was applied to samples from healthy volunteers and compared to analysis results obtained by ICP-OES showing good agreement. Sample volumes as low as 50 μL were sufficient for the quantification of Na, Mg, P, S, K, Ca, Fe, and Zn in whole blood, and Na, Mg, P, S, K, and Ca in plasma samples without significant matrix effects being observed. Chlorine, which is also an electrolyte element present in high enough concentrations for determination by PIXE, was not addressed in this study due to a lack of reference materials. The results highlight PIXE as a viable alternative to other techniques that are sensitive to matrix issues, require larger sample volumes and/or sample treatment. Overall, this work establishes DMS sampling as being suitable for direct multi-element analysis of biological samples by PIXE, offering detection limits at the mg/L level which is sufficient for determination of electrolyte and essential trace elements and paving the way for its broader application in clinical and research settings.
干血斑（DMS）方法最初是为新生儿血液筛查而开发的，由于其在处理小样本量方面的效率以及对多种分析技术的适应性，已在各个研究领域得到广泛应用。本研究展示了首次使用粒子诱导X射线发射（PIXE）对人血和血浆样本的DMS进行直接多元素分析的系统研究结果。采用内标加入法解决DMS的异质性问题，并消除确定等效样本体积的需求，从而实现单点（单打孔）测量。使用参考物质对该方法的线性、准确性、精密度和检测限（LOD）进行了测试。将其应用于健康志愿者的样本，并与电感耦合等离子体发射光谱法（ICP-OES）获得的分析结果进行比较，结果显示一致性良好。低至50 μL的样本量足以定量全血中的钠、镁、磷、硫、钾、钙、铁和锌，以及血浆样本中的钠、镁、磷、硫、钾和钙，且未观察到明显的基质效应。氯也是一种电解质元素，其浓度足够高，可通过PIXE进行测定，但由于缺乏参考物质，本研究未涉及。结果表明，PIXE是其他对基质问题敏感、需要更大样本量和/或样本处理的技术的可行替代方法。总体而言，这项工作确定DMS采样适用于通过PIXE对生物样本进行直接多元素分析，提供毫克/升水平的检测限，足以测定电解质和必需微量元素，并为其在临床和研究环境中的更广泛应用铺平了道路。
