Sensitive optical biosensors for unlabeled targets: a review

Anal Chim Acta. 2008 Jul 14;620(1-2):8-26. doi: 10.1016/j.aca.2008.05.022. Epub 2008 May 18.


This article reviews the recent progress in optical biosensors that use the label-free detection protocol, in which biomolecules are unlabeled or unmodified, and are detected in their natural forms. In particular, it will focus on the optical biosensors that utilize the refractive index change as the sensing transduction signal. Various optical label-free biosensing platforms will be introduced, including, but not limited to, surface plasmon resonance, interferometers, waveguides, fiber gratings, ring resonators, and photonic crystals. Emphasis will be given to the description of optical structures and their respective sensing mechanisms. Examples of detecting various types of biomolecules will be presented. Wherever possible, the sensing performance of each optical structure will be evaluated and compared in terms of sensitivity and detection limit.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Biosensing Techniques / methods*
  • Crystallization
  • Humans
  • Optics and Photonics*
  • Photochemistry
  • Sensitivity and Specificity
  • Surface Plasmon Resonance