Department of Chemistry, Laboratory for Biological Mass Spectrometry, Texas A&M University, College Station, Texas 77843, USA.
Langmuir. 2013 May 28;29(21):6502-7. doi: 10.1021/la4008526. Epub 2013 May 14.
A porous silver-nanoparticle (AgNP)-embedded thin film biosensor was produced by the sol-gel method. The thin films were used as matrix-free laser desorption ionization mass spectrometry (LDI-MS) biosensors applicable to several chemical classes. In these experiments, UV laser irradiation (337 nm) of the AgNP facilitates desorption and ionization of a number of peptides, triglycerides, and phospholipids. Preferential ionization of sterols from vesicles composed of olefinic phosphosphatidylcholines is also demonstrated, offering the possibility for a simplified approach for sterol analysis from complex mixtures. The composition of the nanoparticles was confirmed by X-ray photoelectron spectroscopy (XPS) and UV-vis spectroscopy. XPS data revealed a binding energy of 368.2 eV, consistent with the previous assignment of the binding energy for the Ag 3d(5/2) peak from Ag(0) at 368.1 ± 0.1 eV. The surface morphology of the thin films was studied by field-emission scanning electron microscopy (FE-SEM) and revealed the presence of nanoparticles and the porous nature of the biosensor.
采用溶胶-凝胶法制备了一种嵌入多孔银纳米颗粒（AgNP）的薄膜生物传感器。这些薄膜可用作无基质激光解吸电离质谱（LDI-MS）生物传感器，适用于多种化学物质类别。在这些实验中，AgNP 的紫外激光辐射（337nm）促进了许多肽、甘油三酯和磷脂的解吸和电离。还证明了由具有烯烃磷脂酰胆碱的囊泡组成的固醇的优先离子化，这为从复杂混合物中简化固醇分析提供了可能性。通过 X 射线光电子能谱（XPS）和紫外-可见光谱证实了纳米颗粒的组成。XPS 数据显示出 368.2eV 的结合能，与先前报道的 Ag(0) 的 Ag 3d(5/2)峰的结合能 368.1±0.1eV 一致。薄膜的表面形态通过场发射扫描电子显微镜（FE-SEM）进行了研究，揭示了纳米颗粒的存在和生物传感器的多孔性质。
