ABSTRACT
This chapter focuses on affinity-based biosensors, which take advantage of the binding of a specific ligand/analyte to a biological molecule. The plasma membrane forms an important sensory interface between a cell and its extra-cellular environment. As an example of recent advances in the receptor-based biosensor field, the present review will focus on olfactory receptor based sensor applications, with specific focus on cell-free systems and incorporation of nanoscale physical detection and transduction systems. Variability between receptor subtypes may exist in their ability to be easily expressed as recombinant proteins in large enough quantities, protein functionalization in lipid bilayers and onto sensor surfaces, protein stability, and ability to effectively transmit a signal to the physical transducer system upon ligand binding. The challenge is to incorporate a multiprotein complex into a cell-free lipid bilayer, keeping in mind correct orientation, protein expression and purification of each component, complex assembly, immobilization onto a sensor platform, and stability.
