ABSTRACT

This chapter reviews the various approaches used to impart biofunctionality to SPR interfaces and structures and hence transforming them into biosensors. In fact, the technique of SPR becomes only interesting when the metallic film supporting the propagation of the plasmons is chemically modified. While bioreceptors can be physisorbed onto the sensor surface, covalent attachment is often preferred, as it provides strong and stable

binding of the receptor to the SPR surface. This allows consequently easy regeneration of the sensor interface using conditions, which can remove the analyte from the surface, but not the attached ligand itself. The literature is rich in examples on the use of SPR. Advances in biology continue to reveal that cell-surface oligosaccharides play an essential role in the development and maintenance of all living systems and that they confer an exquisite level of structural and functional diversity characteristic of higher organisms [1, 2]. Despite the ubiquity and importance of carbohydrates in biology,

difficulties in the study of carbohydrate interactions have hindered the development of a mechanistic understanding of carbohydrate structure and function. The structural complexity of carbohydrates is one of the major obstacles. In addition, the binding affinities are typically weak in the 10-3 to 10-6 M range of dissociation constants, compared with antibody-antigen interactions (10-8 to 10-12 M). SPR technology has allowed answering several of open questions over the years.In this chapter, we focus on surface chemistry approaches developed for the fabrication of glycan-modified SPR interfaces.