Detection of Toxins Using Immobilized Carbohydrates as Recognition Elements

摘要

Carbohydrate-protein interactions are important in many recognition processes that occur on cell surfaces. Bacteria, viruses and toxins use these interactions to bind to the host cells and confer pathogenic properties. These include botulinum, cholera, tetanus, diphtheria, and shiga-like (verotoxins) toxins, as well as influenza virus. In this study, we employed immobilized carbohydrate receptors on an array biosensor to detect protein toxins. Two carbohydrate derivatives: N-acetylneuraminic acid, also known as sialic acid (Neu-5Ac), and N-acetylgalactosamine (GalNAc) were immobilized on planar waveguides and interrogated with fluorescently labeled cholera and tetanus toxins. Signals obtained were dose-dependent and indicated that the surface density of the immobilized sugars affected toxin binding.