Carbohydrate‐Modified Gold Nanoparticles

Carbohydrate-modified nanoparticles (glyconanoparticles) have been introduced as an attractive platform for studying and intervening in carbohydrate–protein and carbohydrate–carbohydrate interactions. This chapter focuses on carbohydrate-modified gold nanoparticles (AuNPs). Covalent anchoring of carbohydrates to nanoparticles requires two key linkages: the formation of a firm covalent bond between the carbohydrate and an aglycone spacer and formation of a bond to the metal surface, typically formation of Au-S bonds. Carbohydrate-modified gold nanoparticles can be prepared from preformed, thiol-functionalized glycoconjugates or by direct coupling of unprotected, unmodified glycans to reactive shell nanoparticles. Highly chemoselective reactions allow the simple and convenient construction of glycoconjugates and carbohydrate- modified gold nanoparticles, even with complex carbohydrates. The chapter highlights a few examples of applications of carbohydrate-modified gold nanoparticles that have been of particular and recent interest, especially for studying carbohydrate–protein interactions ex vivo and for in vivo or in vitro diagnostics.