2-Hydrazinoterephthalic Acid as a Novel Negative-Ion Matrix-Assisted Laser Desorption/Ionization Matrix for Qualitative and Quantitative Matrix-Assisted Laser Desorption/Ionization–Mass Spectrometry Analysis of <i>N</i>-Glycans in Peach Allergy Research
Huiwen Wang, Yuexia Gao, Quan He, Jiancong Liao, Shiwen Zhou, Yaqin Liu, Cheng Guo, Xian Li, Xiaoyong Zhao, Yuanjiang Pan
Abstract
Glycans recently attracted considerable attention as the proposal of cross-reactive carbohydrate determinants for food allergy. Matrix-assisted laser desorption/ionization–mass spectrometry (MALDI–MS) is powerful in analyzing biomolecules, while its applications in glycans are still challenging. Herein, a novel reactive matrix-assisted laser desorption/ionization (MALDI) matrix, 2-hydrazinoterephthalic acid, was rationally designed and synthesized. It provides uniform co-crystallization with glycans and only produces deprotonated ions with high intensities in the negative-ion mode. In combination with sinapic acid, a rapid and high-throughput method was established for on-target analysis of glycans with a superior limit of detection at the femtomole level and a good linearity (R2 > 0.999). Furthermore, the established method was successfully applied to quantify N-glycans in different cultivars and tissues of peach [Prunus persica (L.) Batsch]. Our work suggests the potential role of N-glycans as biomarkers for food-borne allergy and lays a methodological foundation for the elucidation of the possible relationship between carbohydrate epitopes and food allergy.