High-Carb Science with Sugarcoated Arrays

© Bob Crimi

Complex carbohydrates play crucial roles in biological processes as diverse as development, infection, and immunity. So naturally, the field has gone 'omic, at least in theory.¹ In practice, good tools have been hard to come by.

Stanford University biologist Denong Wang, formerly of the Columbia University Genome Center, set out to give glycomicists the chip capacity and manufacturing prowess that have transformed genomics. Like proteins, carbohydrates must maintain a specific three-dimensional structure to remain active, and retention of this structure on the chips requires a suitable immobilization surface. Wang's solution uses off-the-shelf glass slides coated with nitrocellulose, which allows unmodified carbohydrate molecules to bind to the surface noncovalently.

Using these slides, immobilized polysaccharides and glyco-conjugates (oligosaccharides coupled to carrier molecules such as proteins and lipids) retained antigenicity. "Nitrocellulose has islands of hydrophobicity and hydrophilicity. Even though the sugar part [of the glycoconjugate molecule] is hydrophilic,...