Département de chimie moléculaire

Carbohydrate microarrays represent powerful tools to study and detect carbohydrate-binding proteins, pathogens or cells. The authors report two original oxime-based methods to prep. surfaces displaying well-defined structures and valency in a given microspot with improved recognition potency with lectins. In a first "direct" approach, fully synthetic aminooxylated glycoclusters have been coated onto aldehyde-activated SiO2 (Si substrate doped with 50 nm thermal oxide layer). To improve the prepn. of the microarray in terms of rapidity and simplicity and to provide addressable surfaces on which sugars can be linked chemoselectively as clusters at defined plots, a second "indirect" strategy has been developed using successive oxime ligation steps. In both cases, binding assays with labeled lectins revealed more potent and selective interaction due to the clustered presentation of sugars. The obsd. differences of interaction have been confirmed in soln. by ITC. [on SciFinder(R)]