Assessment of Glycoprotein Interactions with 4-[(2-aminoethyl)carbamoyl]phenylboronic Acid Surfaces Using Surface Plasmon Resonance Spectroscopy

摘要

Reported here are analyses of the interactions between anselect group of solution-phase glycoproteins and a uniquenboronic acid capture surface. The boronic acid derivative,n4-[(2-aminoethyl)carbamoyl]phenylboronic acid, AECPBA,nwas synthesized and then immobilized on carboxymethylndextran surfaces using simple coupling methods.nFrom surface plasmon resonance spectroscopy responses,nit is found that model glycoproteins interact strongly withnthe AECPBA surface and subsequently can be readilynreleased from the AECPBA surface using borate buffer.nA striking difference between the glycoproteins fetuin andnasialofetuin (desialylated fetuin), in terms of glycoproteinnbinding to the AECPBA surface, indicates that the interactionnof glycoproteins with the immobilized AECPBA isndictated by the terminal saccharide of the heteroglycannchain. Surprisingly, secondary interactions of glycosylatednand nonglycosylated proteins with the carboxymethylndextran hydrogel matrix are observed. Importantly, it isndemonstrated that use of tris(hydroxymethyl)aminomethanenbuffer allows for decreased secondary interactionsnof nonglycosylated proteins on the AECPBA/dextrannsurface, as noted with the model protein ExtrAvidin.