Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University in Toruń, Wileńska 4 Str., 87-100 Toruń, Poland.
Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, Lwowska 1 Str., 87-100 Toruń, Poland.
J Am Soc Mass Spectrom. 2024 Sep 4;35(9):2041-2055. doi: 10.1021/jasms.4c00071. Epub 2024 Aug 14.
In this investigation, we detail the synthesis of silver nanoparticles (AgNPs) via a precise chemical vacuum deposition (CVD) methodology, aimed at augmenting the analytical performance of laser desorption/ionization mass spectrometry (LDI-MS) for the detection of low-molecular-weight analytes. Employing a precursor supply rate of 0.0014 mg/s facilitated the formation of uniformly dispersed AgNPs, characterized by SEM and AFM to have an average diameter of 33.5 ± 1.5 nm and a surface roughness () of 11.8 nm, indicative of their homogeneous coverage and spherical morphology. XPS and SEM-EDX analyses confirmed the metallic silver composition of the nanoparticles with Ag peak splitting, reflecting the successful synthesis of metallic Ag. Comparative analytical evaluation with traditional MALDI matrices revealed that AgNPs significantly reduce signal suppression, thereby enhancing the sensitivity and specificity of LDI-MS for low-molecular-weight compounds such as triglycerides, saccharides, amino acids, and carboxylic acids. Notably, the application of AgNPs demonstrated a superior linear response for triglyceride signals with regression coefficients surpassing 0.99, markedly outperforming conventional matrices. The study further extends into quantitative analysis through nanoparticle-based laser desorption/ionization (NALDI), where AgNPs exhibited enhanced ionization efficiency, characterized by substantially lower limits of detection (LOD) and quantification (LOQ) for tested standards. Particular attention was paid to lipids with a detailed examination of their fragmentation pathways. These results highlight the significant potential of AgNPs synthesized via CVD to transform the analytical detection and quantification of low-molecular-weight compounds using NALDI. This approach offers a promising avenue for expanding the scope of analytical applications in mass spectrometry and introducing innovative methodologies for enhanced precision and sensitivity.
在这项研究中，我们详细介绍了通过精确的化学气相沉积（CVD）方法合成银纳米粒子（AgNPs），旨在提高激光解吸/电离质谱（LDI-MS）对低分子量分析物的检测分析性能。采用 0.0014 mg/s 的前体供给速率，有利于形成均匀分散的 AgNPs，通过 SEM 和 AFM 对其进行表征，平均粒径为 33.5 ± 1.5nm，表面粗糙度（Ra）为 11.8nm，表明其具有均匀的覆盖度和球形形态。XPS 和 SEM-EDX 分析证实了纳米粒子的金属银组成，Ag 峰分裂反映了金属 Ag 的成功合成。与传统的 MALDI 基质进行的比较分析评估表明，AgNPs 显著降低了信号抑制，从而提高了 LDI-MS 对低分子量化合物（如三酰甘油、糖、氨基酸和羧酸）的灵敏度和特异性。值得注意的是，AgNPs 的应用为三酰甘油信号提供了卓越的线性响应，其回归系数超过 0.99，明显优于传统基质。该研究进一步通过基于纳米粒子的激光解吸/电离（NALDI）扩展到定量分析，AgNPs 表现出增强的离子化效率，其检测标准的检测限（LOD）和定量限（LOQ）明显更低。特别关注脂质，详细研究了它们的断裂途径。这些结果突出了通过 CVD 合成的 AgNPs 在使用 NALDI 对低分子量化合物进行分析检测和定量方面的巨大潜力。该方法为扩展质谱分析应用范围提供了有前途的途径，并引入了用于提高精度和灵敏度的创新方法。
