ABSTRACT
Affinity-based optical biosensors represent a highly evolved state of analytical affinity chromatography. In this approach, packed columns are replaced with thin-layer surfaces. Moreover, postcolumn detection based on radioactivity, ultraviolet or visible absorbance,
fluorescence, or light scattering is replaced by a single surface-integrated sensor. Instead of monitoring a binding process indirectly through the use of elution times, as is employed in analytical affinity chromatography, biosensors monitor formation of complexes directly on a surface. This is done in real time and without the need for labeling. These properties-plus the speed and flexibility of optical biosensors — have made these devices indispensable tools for the life sciences and pharmaceutical research.
