Mickan, S.Menikh, A.Munch, J.Abbott, D.Zhang, X.Nicolau, D.V.Lee, A.P.2007-05-142007-05-142002Biomedical applications of micro- and nanotechnology : 16-18 December 2002, Melbourne, Australia / Dan V. Nicolau, Abraham P. Lee (eds.), pp. 334-342.08194473230277-786Xhttp://hdl.handle.net/2440/29336© 2003 COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.A new bioaffinity sensor based on pulsed terahertz (THz) spectroscopy is able to sensitively detect the presence of ultra-thin bound biomolecular layers. The protein avidin and lipid biotin are noted for their very high binding affinity, and the ease for which they can be attached to residues with importance in many biosensing applications. We demonstrate the sensitivity of the pulsed THz spectrometer to thin avidin layers and to avidin amplified with micron-sized agarose beads. The experimental results can be simply modelled by considering transmission of the THz radiation at the thin film interfaces. We detect less than 10.3 ng/cm2 avidin, giving the THz system a detection capability of sub-thin solid films better than ellipsometry and reflectometry techniques.enConference paper002002253110.1117/12.4881430001813948000372-s2.0-003864178659285Abbott, D. [0000-0002-0945-2674]