Advancing Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometric Imaging for Capillary Electrophoresis Analysis of Peptides

作者：Wang Junhua; Ye Hui; Zhang Zichuan; Xiang Feng; Girdaukas Gary; Li Lingjun^*

来源：Analytical Chemistry, 2011, 83(9): 3462-3469.

DOI：10.1021/ac200708f

In this work, the utilization of matrix-assisted laser desorption/ionization-mass spectrometric imaging (MALDI-MSI) for capillary electrophoresis (CE) analysis of peptides based on a simple and robust off-line interface has been investigated. The interface involves sliding the CE capillary distal end within a machined groove on a MALDI sample plate, which is precoated with a thin layer of matrix for continuous sample deposition. MALDI-MSI by time of flight (TOF)/TOF along the CE track enables high-resolution and high-sensitivity detection of peptides, allowing the reconstruction of a CE electropherogram while providing accurate mass measurements and structural identification of molecules. Neuropeptide standards and their HID isotopic formaldehyde-labeled derivatives were analyzed using this new platform. Normalized intensity ratios of individual ions extracted from the CE trace were compared to MALDI-MS direct analysis and the theoretical ratios. The CE MALDI-MSI results show potential for sensitive and quantitative analysis of peptide mixtures spanning a wide dynamic range.

• 出版日期2011-5-1