期刊
COLA'05: 8TH INTERNATIONAL CONFERENCE ON LASER ABLATION
卷 59, 期 -, 页码 548-+出版社
IOP PUBLISHING LTD
DOI: 10.1088/1742-6596/59/1/117
关键词
-
类别
资金
- US. Department of Energy [DE-FG02-01ER15129]
- W. M. Keck Foundation [041904]
- George Washington University Research Enhancement Fund (GWU-REF)
- U.S. Department of Energy (DOE) [DE-FG02-01ER15129] Funding Source: U.S. Department of Energy (DOE)
Due to their optical properties and morphology, thin films formed of nanoparticles are potentially new platforms for soft laser desorption/ionization (SLDI) mass spectrometry. Thin films of gold nanoparticles (with 12 +/- 1 nm particle size) were prepared by evaporation-driven vertical colloidal deposition and used to analyze a series of directly deposited polypeptide samples. In this new SLDI method, the required laser fluence for ion detection was equal or less than what was needed for matrix-assisted laser desorption/ionization (MALDI) but the resulting spectra were free of matrix interferences. A silicon microcolumn array-based substrate (a.k.a. black silicon) was developed as a new matrix-free laser desorption ionization surface. When low-resistivity silicon wafers were processed with a 22 ps pulse length 3x omega Nd:YAG laser in air, SF6 or water environment, regularly arranged conical spikes emerged. The radii of the spike tips varied with the processing environment, ranging from approximately 500 nm in water, to similar to 2 Pin in SF6 gas and to similar to 5 mu m in air. Peptide mass spectra directly induced by a nitrogen laser showed the formation of protonated ions of angiotensin I and II, substance P, bradykinin fragment 1-7, synthetic peptide, pro14-arg, and insulin from the processed silicon surfaces but not from the unprocessed areas. Threshold fluences for desorption/ionization were similar to those used in MALDI. Although compared to silicon nanowires the threshold laser pulse energy for ionization is significantly (-10x) higher, the ease of production and robustness of microcolumn arrays offer complementary benefits.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据