Glycan-protein interactions play important biological roles in biological processes. But there is a lack of simple high-throughput methods to elucidate recognition events between carbohydrates and protein. Although, there have been a number of glycan arrays developed in recent years utilizing different strategies and for different purposes, the method presented in this paper, a direct covalent immobilization of sugars to hydroxyl-modified glass surface, can be a very useful general method. Here, two strategies have been developed for the production of carbohydrate microarrays by the underivatized sugars that efficiently immobilized on hydroxyl-functionalized glass surface by formation of glycosidic bond with the hemiacetal group at the reducing end of the suitable carbohydrates via condensation. Firstly, untreated glass slides were amino- and epoxy-silanized, respectively. Then, they were further hydroxyl functionalized with different surface chemistries. The carbohydrate microarrays were fabricated on hydroxyl-functionalized glass by robotic arrayer. Additionally, experiments for the characterization of carbohydrates-protein interaction were performed to compare these strategies. Overall best results in terms of conveniency and sensitivity were obtained with hydroxyl-functionalization on epoxysilanized surfaces. The hydroxyl-functionalized slide was used to detect the amount of mannose immobilized on the glass surface. The limit of detection of the fabricated mannose microarray was 100 nM.
Keywords: Carbohydrate microarrays, carbohydrate-protein interaction, glycosidic bond, hydroxyl-modified surface