Sensitive optical biosensors for unlabeled targets: A review

• Published in: Analytica chimica acta 2008-07, Vol.620 (1), p.8-26
• Main Authors: Fan, Xudong, White, Ian M., Shopova, Siyka I., Zhu, Hongying, Suter, Jonathan D., Sun, Yuze
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Biological and medical sciences; Biosensing Techniques - methods; Biosensors; Biotechnology; Chemistry; Crystallization; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General, instrumentation; Humans; Label-free; Methods. Procedures. Technologies; Optical biosensor; Optics and Photonics; Photochemistry; Photonic biosensor; Refractive index; Sensitivity and Specificity; Surface Plasmon Resonance; Various methods and equipments
• ISSN: 0003-2670; 1873-4324; 1873-4324
• DOI: 10.1016/j.aca.2008.05.022

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.