Department of Chemistry, University of Florida, Gainesville, Florida, USA.
Anal Chem. 2010 Sep 15;82(18):7566-75. doi: 10.1021/ac101149b.
This paper describes a new technique for fabrication of nanostructured porous silicon (pSi) for laser desorption ionization mass spectrometry. Porous silicon nanowell arrays were prepared by argon plasma etching through an alumina mask. Porous silicon prepared in this way proved to be an excellent substrate for desorption/ionization on silicon (DIOS) mass spectrometry (MS) using adenosine, Pro-Leu-Gly tripeptide, and [Des-Arg(9)]-bradykinin as the model compounds. It also allows the analyses of complex biological samples such as a tryptic digest of bovine serum albumin and a carnitine standard mixture. Nanowell array surfaces were also used for direct quantification of the illicit drug fentanyl in red blood cell extracts. This method also allows full control of the surface features. MS results suggested that the pore depth has a significant effect on the ion signals. Significant improvement in the ionization was observed by increasing the pore depth from 10 to 50 nm. These substrates are useful for laser desorption ionization in both the atmospheric pressure and vacuum regimes.
本文介绍了一种用于激光解吸电离质谱的纳米结构多孔硅(pSi)制备新技术。通过氧化铝掩模进行氩等离子体刻蚀,制备了多孔硅纳米井阵列。通过这种方法制备的多孔硅被证明是使用腺苷、Pro-Leu-Gly 三肽和[Des-Arg(9)]-缓激肽作为模型化合物进行硅上解吸/电离(DIOS)质谱(MS)的优异基底。它还允许对复杂的生物样品进行分析,如牛血清白蛋白的胰蛋白酶消化物和肉碱标准混合物。纳米井阵列表面还用于直接定量红细胞提取物中的非法药物芬太尼。该方法还可以完全控制表面特性。MS 结果表明,孔深对离子信号有显著影响。通过将孔深从 10nm 增加到 50nm,观察到离子化的显著改善。这些基底在大气压和真空两种环境下都适用于激光解吸电离。