Evanescent wave biosensors with a hydrogel binding matrix

Hydrogels have become widely used materials in numerous important fields such as drug delivery and tissue engineering and have allowed great improvements in the performance of analytical and bioanalytical technologies for detection of chemical and biological species. Their highly open structure makes them attractive to serve as a binding matrix that can accommodate large amounts of target analyte, provide a natural microenvironment for biomolecular recognition elements, and enable design of surfaces that can resist nonspecific adsorption from complex samples for highly specific biosensor devices. In addition, a special class of "smart" hydrogels responsive to external stimuli (e.g., through temperature or pH changes) holds potential for development of biosensors with enhanced sensitivity and implementing of new biosensor schemes for sensitive analysis of molecular analytes. This chapter provides an overview of recent advances in our and other laboratories, as well as ractical leads for design, characterization, and implementation of hydrogel surface architectures for ultrasensitive affinity biosensors based on evanescent wave optics.