Nanoengineered micro gold shells for LDI-TOF analysis of small molecules

Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Republic of Korea.
Analytica chimica acta (Impact Factor: 4.51). 07/2012; 736:1-6. DOI: 10.1016/j.aca.2012.05.040
Source: PubMed


This paper reports on analyses of small molecules with laser desorption/ionization time of flight (LDI-TOF) mass spectrometry (MS) using nanostructure-embedded micro gold shells (μAuSs). The mass analyses of amino acids, sugars, peptides, and their mixtures gave apparent mass peaks for analytes without any significant background interferences. μAuSs afforded a better limit of detection (LOD) and a higher signal-to-noise ratio than gold nanoparticles, which are commonly used for LDI-TOF analysis of small molecules. We believe μAuSs have advantages in terms of simplicity, detection limit, and reproducibility, and therefore, they constitute a significant addition to the organic matrix-free analytical tools that are currently in wide use.

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