State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Anal Chem. 2011 May 15;83(10):3668-74. doi: 10.1021/ac103222p. Epub 2011 Apr 14.
Au nanoporous films (NPFs) with different surface modification and morphology were fabricated and utilized as substrates for the analysis of a series of compounds, including amino acids, drug, cyclodextrins, peptides, and polyethylene glycols, using surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS). It was found that the size and interconnection state of the NPF ligament as well as the surface modification are key parameters that affect the laser desorption/ionization performance. Compared with 2,5-dihydroxybenzoic acid, pristine NPF, and aminobenzenethiol or 3-mercaptopropanoic acid modified Au NPFs, cysteine modified Au NPF generated intense and background-suppressing mass spectra. Regarding the effect of Au NPF morphology, the Au NPF with nanopores in the range of 10-30 nm, ligament size of 5 nm, and electrochemistry surface area of 26.1 m(2)/g exhibited the highest performance as a substrate. This high-performance NPFs can be easily fabricated by capping agent replacement induced self-organization of ultrathin nanowires, followed by self-assembling of a monolayer (SAM) of cysteine. The good thermal/electroconductivity and uniformity of Au NPFs avoided the fragmentation of analytes, eliminated the intrinsic matrix ions interference, and provided good reproducibility (RSD ≤ 10%). Additionally, the fabricated NPFs can be easy divided into microarrays (a ~4 × 4 array from a 1 cm × 1 cm NPF). This work provides a simple and cost-effective route for acquiring an Au nanostructure as a SALDI substrate, which offers a new technique for high-speed analysis of low-molecular weight compounds.
金纳米多孔薄膜（NPFs）具有不同的表面修饰和形态，被制备并用作一系列化合物分析的基底，包括氨基酸、药物、环糊精、肽和聚乙二醇，使用表面辅助激光解吸/电离飞行时间质谱（SALDI-TOF MS）。结果发现，NPF 键的大小和互连状态以及表面修饰是影响激光解吸/电离性能的关键参数。与 2,5-二羟基苯甲酸、原始 NPF、氨基苯硫醇或 3-巯基丙酸修饰的 Au NPF 相比，半胱氨酸修饰的 Au NPF 产生了强烈且背景抑制的质谱。关于 Au NPF 形态的影响，具有 10-30nm 范围内纳米孔、5nm 键大小和 26.1m2/g 电化学表面积的 Au NPF 表现出作为基底的最高性能。这种高性能的 NPFs 可以通过封端剂置换诱导超薄纳米线的自组织，然后自组装半胱氨酸的单层（SAM）来轻松制备。Au NPFs 的良好的热/电导率和均匀性避免了分析物的碎片化，消除了固有基质离子的干扰，并提供了良好的重现性（RSD≤10%）。此外，所制备的 NPFs 可以容易地分成微阵列（从 1cm×1cm 的 NPF 得到一个约 4×4 的阵列）。这项工作提供了一种简单且具有成本效益的方法来获取 Au 纳米结构作为 SALDI 基底，为低分子量化合物的高速分析提供了一种新技术。
