title: Real-time optical biosensor based on differential phase measurement of surface plasmon resonance.
abstract: We report a real-time differential phase measurement technique which can be implemented in optical surface plasmon resonance biosensors. The important feature of our design is that sensitivity has been greatly improved by measuring the differential phase change between the s and p-polarizations. Real-time measurement capability is achieved by using a phase extracting routine which continuously monitors the waveforms captured by two photo-detectors. Measurement capability of our setup is demonstrated through real-time monitoring of bovine serum albumin (BSA)/anti-BSA binding reaction. The estimated sensitivity of our current setup is 7.4 ng/ml.
authors.affiliation: Department of Electronic Engineering, Center for Advanced Research in Photonics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR of China, Hong Kong. hpho@ee.cuhk.edu.hk
authors.forename: H P
authors.initials: HP
authors.lastname: Ho
authors.forename: W C
authors.initials: WC
authors.lastname: Law
authors.forename: S Y
authors.initials: SY
authors.lastname: Wu
authors.forename: Chinlon
authors.initials: C
authors.lastname: Lin
authors.forename: S K
authors.initials: SK
authors.lastname: Kong
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D003199:Computer Systems; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D008832:Microchemistry / Q000295:instrumentation* / Q000379:methods; D055095:Optics and Photonics / Q000295:instrumentation*; D012710:Serum Albumin, Bovine / Q000032:analysis* / Q000276:immunology*; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods
chemical_list: D012710:Serum Albumin, Bovine