Elegant Chemistry to Directly Anchor Intact Saccharides on Solid Surfaces Used for the Fabrication of Bioactivity-Conserved Saccharide Microarrays

Abstract

An easy chemical strategy was proposed and used to establish a method for direct anchoring of intact saccharides on solid surfaces with well conserved bioaffinity. The anchoring was achieved by temperature-modulated stepwise reactions with cyanuric chloride as a key linker, and was successfully applied to the fabrication of saccharide chips. To demonstrate, 15 intact reducing and nonreducing saccharides with various molecular sizes were dotted on a cyanuric-chloride-modified chip (1.0 × 1.0 cm(2)) and made to react with lectins. As expected, the anchored saccharides were capable of recognizing their target lectins, and more exciting were the perfect conservation of the specific recognizing ability of the anchored monosaccharides such as mannose, glucose, and even fructose (interacting only weakly with concanavalin A). This conservation was ascribed to the maintenance of the original structure (especially the anomeric configuration) of saccharides after immobilization and to the allowance of the anchored saccharides to rotate with and/or on the scaffold of cyanuric chloride, which makes them easily adapt to the recognition-preferred spatial position. The expected linkage of saccharides on cyanuric chloride and the maintenance of their anomeric configuration were characterized by mass spectrometry and nuclear magnetic resonance, respectively. The new method can be highlighted not only by its conservation of saccharide bioaffinity and universal applicability but also by its merits of easy manipulation or facile control of the reactions and cost-effectiveness due to the use of extremely cheap cyanuric chloride.