Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Anal Chem. 2013 Jul 16;85(14):6646-52. doi: 10.1021/ac401601r. Epub 2013 Jul 5.
Carbon nanodots were applied for the first time as a new matrix for the analysis of low-molecular-weight compounds by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in both positive- and negative-ion modes. A wide range of small molecules including amino acids, peptides, fatty acids, as well as β-agonists and neutral oligosaccharides were analyzed by MALDI MS with carbon nanodots as the matrix, and the lowest 0.2 fmol limits-of-detection were obtained for octadecanoic acid. Clear sodium and potassium adducts and deprotonated signals were produced in positive- and negative-ion modes. Furthermore, the glucose and uric acid in real samples were quantitatively determined by the internal standard method with the linear range of 0.5-9 mM and 0.1-1.8 mM (R(2) > 0.999), respectively. This work gives new insight into the application of carbon nanodots and provides a general approach for rapid analysis of low-molecular-weight compounds.
碳纳米点首次被应用于基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF MS）分析中，在正、负离子模式下分析了包括氨基酸、肽、脂肪酸、β-激动剂和中性寡糖在内的多种小分子。以碳纳米点作为基质，用 MALDI MS 分析了这些小分子，得到了十八烷酸的最低检出限为 0.2 fmol。在正、负离子模式下，均产生了清晰的钠离子和钾离子加合物以及去质子化信号。此外，还通过内标法对实际样品中的葡萄糖和尿酸进行了定量测定，线性范围分别为 0.5-9 mM 和 0.1-1.8 mM（R²>0.999）。这项工作为碳纳米点的应用提供了新的思路，并为快速分析低分子量化合物提供了一种通用方法。
