Recent research has focused on increasing the evidentiary value of latent fingerprints through chemical analysis. Although researchers have optimized the use of organic and metal matrices for matrix‐assisted laser desorption/ionization‐mass spectrometry imaging (MALDI‐MSI) of latent fingerprints, the use of development powders as matrices has not been fully investigated. Carbon forensic powder (CFP), a common nonporous development technique, was shown to be an efficient one‐step matrix; however, a high‐resolution mass spectrometer was required in the low mass range due to carbon clusters. Titanium oxide (TiO₂) is another commonly used development powder, especially for dark nonporous surfaces. Here, forensic TiO₂ powder is utilized as a single‐step development and matrix technique for chemical imaging of latent fingerprints without the requirement of a high‐resolution mass spectrometer. All studied compounds were successfully detected when TiO₂ was used as the matrix in positive mode, although, generally, the overall ion signals were lower than the previously studied CFP. TiO₂ provided quality mass spectrometry (MS) images of endogenous and exogenous latent fingerprint compounds. The subsequent addition of traditional matrices on top of the TiO₂ powder was ineffective for universal detection of latent fingerprint compounds. Forensic TiO₂ development powder works as an efficient single‐step development and matrix technique for MALDI‐MSI analysis of latent fingerprints in positive mode and does not require a high‐resolution mass spectrometer for analysis.

中文翻译：

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使用二氧化钛显影粉作为现有基质对潜在指纹进行质谱成像。

最近的研究集中在通过化学分析增加潜在指纹的证据价值。尽管研究人员已经优化了有机和金属基质在潜在指纹的基质辅助激光解吸/电离质谱成像（MALDI-MSI）成像中的应用，但尚未对使用显影粉作为基质进行充分研究。碳取证粉末（CFP）是一种常见的无孔显影技术，被证明是一种有效的一步法基质。但是，由于碳簇，在低质量范围内需要高分辨率质谱仪。氧化钛（TiO ₂）是另一种常用的显影粉，特别是用于深色无孔表面。在这里，法医TiO ₂粉末无需经过高分辨率质谱仪即可作为单步开发和基质技术用于潜在指纹的化学成像。当将TiO ₂用作正离子基体时，可以成功检测到所有研究的化合物，尽管通常总的离子信号低于先前研究的CFP。TiO ₂提供了内源性和外源性潜在指纹化合物的高质量质谱（MS）图像。随后在TiO ₂粉末顶部添加传统基质对于通用检测潜在的指纹化合物无效。法医TiO ₂ 显影粉可作为一种有效的单步开发和基质技术，用于以正模进行MALDI-MSI分析潜伏指纹，并且不需要高分辨率质谱仪进行分析。