A novel design of surface plasmon resonance fiber optic sensor is reported which leads to a compact, highly miniaturized sensing element with excellent sensitivity. The sensing device is based on a side-polished single-mode optical fiber with a thin metal overlayer supporting surface plasmon waves. The strength of interaction between a fiber mode and a surface plasmon wave depends strongly on the refractive index near the sensing surface. Therefore, refractive index changes associated with biospecific interaction between antibodies immobilized on the sensor and antigen molecules can be monitored by measuring light intensity variations. Detection of horse radish peroxidase (HRP) of the concentration of 100 ng/ml has been accomplished using the fiber optic sensor with a matrix of monoclonal antibodies against HRP immobilized on the sensor surface.

Date Published: 15 January 1999
PDF: 8 pages
Proc. SPIE 3570, Biomedical Sensors, Fibers, and Optical Delivery Systems, (15 January 1999); doi: 10.1117/12.336929

Published in SPIE Proceedings Vol. 3570:
Biomedical Sensors, Fibers, and Optical Delivery Systems
Francesco Baldini; Nathan I. Croitoru; Martin Frenz; Ingemar Lundstroem; Mitsunobu Miyagi; Riccardo Pratesi; Otto S. Wolfbeis, Editor(s)