This analysis of optical biosensors and relevant technologies focuses both on technologies and advances that will influence the future of optical biosensor development, including several technological advances not yet greatly explored within this field. The book is divided into two parts: The first part focuses on 21st-century technology and here leaders in each field describe the underlying principles behind each technology. The authors then enumerate the types of applications for which it has been tested, provide opinions about the advantages and disadvantages of the biosensor and philosophize on future developments using that particular biosensor. The second part deals with the science for future technology developments including four different methods for producing new recognition elements (genetic engineering of proteins, chemical synthesis, molecular imprinting and combinatorial selection of nucleotide-based receptors); two methods for immobilizing receptors on biosensors (sol gels and semi-synthetic membranes); two methods for producing very bright signals (PEBBLES and quantum dots) and soft lithography for surface patterning and microfluidics.