Chemo-Enzymatic Synthesis of Branched Glycopolymer Brushes as an Artificial Glycocalyx for Lectin Specific Binding

Artificial glycocalyx fabricated by carbohydrates is of interest because it provides a platform to simulate the cell membranes those widely exists in the nature, thus enable extensive applications to be implantable in bioengineering. Here, we present a green strategy combining two polymerization techniques, surface-initiated atom transfer radical polymerization (SI-ATRP) and enzyme-catalyzed elongation (ECE) of polysaccharide, for fabricating a densely packed branched glycopolymer brushes on the gold surface as artificial glycocalyx. In this strategy, SI-ATRP is first performed to graft a linear polymer chain for anchoring maltose, which can be used as enzyme acceptor for dextransucrase (DSase). Under the DSase, branched polysaccharide is efficiently formed through elongation of sucrose substrate. Undoubtedly, enzymatic transglycosylation has unique advantages, such as green, regio- and stereo-selective, etc. The process of DSase-catalyzed polysaccharide is well monitored by quartz crystal microbalance (Q...