Kim Young-Kwan, Min Dal-Hee
Center for RNA Research, Institute for Basic Science, and ‡Department of Chemistry, Seoul National University , Seoul 151-747, Republic of Korea.
Langmuir. 2014 Oct 28;30(42):12675-83. doi: 10.1021/la5027653. Epub 2014 Oct 17.
Graphene and graphene oxide (GO) films have been explored to develop an efficient laser desorption/ionization mass spectrometry (LDI-MS) platform for the analysis of chemically and biologically important small molecules. The GO films were prepared by layer-by-layer (LBL) assembly cycles (one to ten layers) with precisely controlled thickness and surface roughness which are important structural factors for laser energy absorption capacity and laser energy transfer for efficient LDI-MS analysis. Amino acids, saccharides, and pyrenylated molecules were analyzed by LDI-MS on the LBL assembled GO films to reveal their structural influence on LDI-MS analysis of small molecules. Then, the structural influence of LBL assembled GO films on synergistic effect was investigated to develop an efficient and widely applicable LDI-MS analysis platform with an additional multiwalled carbon nanotube (MWCNT) layer. We found that the optimum number of GO film layers for LDI-MS analysis was dependent on the chemical structures of small molecules, and the laser energy threshold needed for LDI of small molecules on GO/MWCNT films could be lowered as the number of LBL assembled GO films increased underneath the MWCNT layer.
人们已探索使用石墨烯和氧化石墨烯（GO）薄膜来开发一种高效的激光解吸/电离质谱（LDI-MS）平台，用于分析化学和生物学上重要的小分子。通过逐层（LBL）组装循环（一到十层）制备GO薄膜，其厚度和表面粗糙度得到精确控制，这是影响激光能量吸收能力和激光能量转移以实现高效LDI-MS分析的重要结构因素。通过LDI-MS对LBL组装的GO薄膜上的氨基酸、糖类和芘基化分子进行分析，以揭示它们对小分子LDI-MS分析的结构影响。然后，研究LBL组装的GO薄膜对协同效应的结构影响，以开发一个高效且广泛适用的LDI-MS分析平台，并添加一个多壁碳纳米管（MWCNT）层。我们发现，用于LDI-MS分析的GO薄膜的最佳层数取决于小分子的化学结构，并且随着MWCNT层下方LBL组装的GO薄膜层数增加，GO/MWCNT薄膜上小分子LDI所需的激光能量阈值可以降低。
