Antibody engineering for biosensor applications

Abstract

Antibodies are a well-established class of affinity reagents used extensively in detection and diagnostic applications. However, while these proteins have been developed to provide considerable functionality in conventional applications (e.g. sandwich ELISA), their exploitation in emergent biosensor technologies requires careful consideration. Historically, diagnostic technologies have been the primary consumer of antibody products. As a result, antibody development has been skewed toward satisfying the requirements of conventional diagnostic assay formats (ostensibly sandwich assays). The resulting catalogue of antibody products provides a convenient resource for potential biosensor exploitation. However, when applied outside of their traditional context (on novel surface/transducer interfaces) they can behave unpredictably and undesirably (e.g. loss of activity or specificity). The surface immobilisation of a recognition element within a biosensor is an invariant feature of biosensor assay design. The resulting interface represents a complex system composed of interdependent technical challenges affecting assay stability, specificity, and sensitivity. It is likely that a holistic approach to interface development is required as the development of individual interface components is unlikely to deliver the technical advances required for the practical exploitation/commercialization of biosensor technologies. The use of antibodies in biosensor applications requires a detailed understanding of their inherent properties and the interface to which they are to be tethered. This chapter illustrates the core properties of antibody structure and function and their significance in biosensing applications. The different classes of antibody reagents available to biosensor developers are discussed with a focus on recombinant antibody technologies. The opportunities available in biosensor development, regarding assay and interface design, are briefly considered. Finally, strategies for the bespoke engineering and application of antibodies in biosensor technologies are discussed in detail. © Springer Science+Business Media, LLC 2010.