Heavy metal pollution emerges as the industry develops, which threads human health severely. Cd is a kind of supervirulent heavy metal which needs inspection for food safety. This thesis studies on the immunosensor technology based on surface plasmon resonance (SPR), successfully detects Cd and introduces the principle of SPR immunosensor detection system. Cd-iEDTA-BSA (complete antigen of Cd) immunosensor has been made by the methods of hybridization product and Cd-iEDTA-BSA antibody. There are clear 3*3 arrays on the sensor chip. Two SPR detection methods of imaging and scanning have been applied to detect the immunoreaction. The picture captured by SPR imaging system can directly observe the phenomena of the surface plasmon resonance on the sample arrays and the immunoreaction from the view of the resonance angle. Besides, the excess content of Cd can be found out by finding in the sample the matched material on the probe of sensor chip. After the immunoreaction the molecular weight of antigen-antibody compound which forms on the surface of the chip increases, so does the refractive index as well as the resonance angle. The resonance system can detect the resonance angle and the refractive index of each position on the sensor chip precisely, and draws the resonance curves. The arrays' resonance curves reflecting the immunocreation have a clear displacement which indicates the increase of the resonance angle as well as the refractive index. The sensitivity of the scanning surface plasmon resonance detection system is higher than the imaging one, which is more convenient and consumes shorter time.

Date Published: 9 November 2010
PDF: 7 pages
Proc. SPIE 7853, Advanced Sensor Systems and Applications IV, 78531U (9 November 2010); doi: 10.1117/12.869029

Published in SPIE Proceedings Vol. 7853:
Advanced Sensor Systems and Applications IV
Brian Culshaw; Yanbiao Liao; Anbo Wang; Xiaoyi Bao; Xudong Fan; Lin Zhang, Editor(s)