Optical immunoassay systems based upon evanescent wave interactions

Douglas A. Christensen; James N. Herron

doi:10.1117/12.237631

1 April 1996 Optical immunoassay systems based upon evanescent wave interactions

Douglas A. Christensen, James N. Herron

Proceedings Volume 2680, Ultrasensitive Biochemical Diagnostics; (1996) https://doi.org/10.1117/12.237631
Event: Photonics West '96, 1996, San Jose, CA, United States

Abstract

Immunoassays based upon evanescent wave interactions are finding increased biosensing application. In these devices, the evanescent tail associated with total internal reflection of an incident beam at the substrate/solution interface provides sensitivity for surface-bound protein over bulk molecules, allowing homogeneous assays and real-time measurement of binding dynamics. Among such systems are surface plasmon resonance sensors and a resonant mirror device. Several research groups are also developing fluorescent fiberoptic or planar waveguide sensors for biomedical applications. We describe a second-generation planar waveguide fluoroimmunoassay system being developed in our laboratory which uses a molded polystyrene sensor. The 633-nm beam from a laser diode is focused into the 500 micrometer- thick planar waveguide by an integral lens. Antibodies to the desired analyte (hCG) are immobilized on the waveguide surface and fluorescence from bound analyte/tracer antibodies in a sandwich format is imaged onto the detector. The geometry of the waveguide allows several zones to be detected, providing the capability for on-sensor calibration. This sensor has shown picomolar sensitivity for the detection of hCG.

Citation Download Citation

Douglas A. Christensen and James N. Herron "Optical immunoassay systems based upon evanescent wave interactions", Proc. SPIE 2680, Ultrasensitive Biochemical Diagnostics, (1 April 1996); https://doi.org/10.1117/12.237631

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available