Ecole des Sciences Criminelles/School of Criminal Justice, Faculty of Law, Criminal Justice, and Public Administration; University of Lausanne, 1015 Lausanne-Dorigny Switzerland.
Unit of Toxicology, CURML, Vulliette 04, 1000 Lausanne 25 Switzerland.
Forensic Sci Int. 2021 Dec;329:111063. doi: 10.1016/j.forsciint.2021.111063. Epub 2021 Oct 21.
In the last decade, there have been many scientific developments regarding the use of mass spectrometry to analyse the composition of fingermarks. In this context, the development of a dedicated quality control test strip would benefit the forensic community by providing a way to assess the reproducibility of the measures as well as to perform inter-laboratory comparisons. To accomplish this goal, the use of a chemical printer offers the possibility of combining a visual template with artificial fingerprint secretions. The design of the quality control test strip as well as the preliminary assessment of its performance with fingermark detection reagents and matrix-assisted laser desorption-ionisation combined with mass spectrometry imaging (MALDI-MSI) are presented in this paper. The chosen template combines two geometric patterns intended to help assess the chemical analysis (full square) and imaging (lined square) capabilities of the instrument. The artificial secretion is composed of two distinct solutions: artificial sweat and artificial sebum. The printing reproducibility and chemical homogeneity of the quality control test strips were assessed in two ways: (1) using MALDI-MSI, the printed pattern was analysed and the m/z values compared to the reference list based on the artificial secretion composition, and (2) using two common fingermark detection techniques, the printed pattern was processed using an amino acid reagent (ninhydrin) and a lipid stain (Oil Red O). Overall, the results highlight the potential of a printed quality control test strip for the assessment of the quality of fingermark detection techniques as well as the possibility of performing quality monitoring of mass-spectrometry-based techniques over time.
在过去的十年中，质谱分析在分析指印成分方面取得了许多科学进展。在这种情况下，开发专用的质量控制测试条将通过提供评估措施重现性以及进行实验室间比较的方法使法医界受益。为了实现这一目标，化学打印机的使用提供了将视觉模板与人工指纹分泌物结合起来的可能性。本文介绍了质量控制测试条的设计以及使用指纹检测试剂和基质辅助激光解吸/离子化与质谱成像（MALDI-MSI）对其性能进行的初步评估。选择的模板结合了两种旨在帮助评估仪器化学分析（完整正方形）和成像（带线正方形）能力的几何图案。人工分泌物由两种不同的溶液组成：人工汗液和人工皮脂。通过两种方式评估质量控制测试条的打印重现性和化学均一性：(1) 使用 MALDI-MSI 分析打印图案，并将 m/z 值与基于人工分泌物组成的参考列表进行比较，(2) 使用两种常见的指纹检测技术，使用氨基酸试剂（茚三酮）和脂质染色剂（油红 O）处理打印图案。总体而言，结果突出了打印质量控制测试条在评估指纹检测技术质量以及随着时间的推移对基于质谱的技术进行质量监测的可能性。
