Monitoring of biological binding reactions by magneto-optical relaxation measurements.

E. Romanus^1,2 - C. Groß¹ - R. Kötitz³ - S. Prass² - J. Lange¹ - P. Weber² - W. Weitschies¹

¹ Institute of Pharmacy, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Str. 17, D-17487 Greifswald, Germany
² Institute of Solid State Physics, Friedrich-Schiller-University Jena, Helmholtzweg 5, D-07743 Jena, Germany
³ Division on Substance Abuse, Department of Psychiatry, Columbia University/NYSPI, Unit 66, 1051 Riverside Drive, New York City, NY 10032. U.S.A.

Abstract
A measurement system for the investigation of the field-induced magnetic transient birefringence was set up and tested with respect to the detection limit for magnetic nanoparticles. Furthermore, the application of the measurement system for the determination of biological binding reactions was investigated. As an example the monitoring of the binding reaction between streptavidin coupled onto the surface of magnetic nanoparticles and biotinylated bovine serum albumin is presented. Figs 5, Refs 11.