Mass spectrometry of carbohydrate-protein interactions on a glycan array conjugated to CVD graphene surfaces

Abstract

Mass spectrometry (MS) is a valuable tool for functional genomic, proteomic, and glycomic studies. In particular, the combination of MS with microarrays is a powerful technique for analyzing the activity of carbohydrate processing enzymes and for the identification of carbohydrate-binding proteins (lectins) in complex matrices. On the other hand, graphene exhibits high desorption/ionization efficiency, good conductivity and optical transparency, specifications of a high-performance component for matrix-assisted laser desorption/ionization (MALDI) platforms. Besides, the chemical functionalization of graphene increases the adsorption capability of functional biomolecules (e.g. receptors), resulting in very stable interfaces. Taking advantage of the properties of graphene, we developed several modified chemical vapor deposited graphene (CVDG)-based glycan arrays on different substrates including ITO and bare glass, as a potential sensing platform for carbohydrate-lectin interactions, which are involved in a plethora of biological processes. The glycan arrays were fully characterized by MALDI-MS analysis and, in some cases, optical microscopy.