Amplified transduction of biomolecular interactions based on the use of nanomaterials

The achievement of very high sensitivity is a major goal in biological assays such as the monitoring of DNA hybridization or protein interactions. This chapter reviews progress in the development of nanomaterials for amplified biosensing and discusses different nanomaterial-based bioamplification strategies. The emergence of nanotechnology is opening new horizons for highly sensitive bioassays and for novel biosensor protocols that employ electronic, optical, or microgravimetric signal transduction. Antibodies or nucleic acids functionalized with metal or semiconductor nanoparticles have been employed as amplifying tags for the biodetection of proteins and DNA. The coupling of different nanomaterial-based amplification platforms and amplification processes dramatically enhances the intensity of the analytical readout and leads to ultrasensitive bioassays. The remarkable sensitivity of the new nanomaterial-based sensing protocols opens up the possibility of detecting disease markers, biothreat agents, or infectious agents that cannot be measured by conventional methods.