| Affiliation: | (1) Thermo Hybaid GmbH, Sedanstraße 10, 89077 Ulm, Germany, DE;(2) University of Linköping, Department of Physics and Measurement Technology, Division of Sensor Science and Molecular Physics, 58183 Linköping, Sweden, SE;(3) Institute of Analytical Chemistry, University of Regensburg, 93040 Regensburg, Germany, DE |
| Abstract: |  Two different types of  -substituted alkanethiol/disulfide compounds have been used to prepare monolayer architectures on gold serving as platforms for the immobilization of receptor probe molecules – antibodies. These are: (i) carboxylic acid alkanethiols post-reacted with amino biotin to generate streptavidin surfaces, and (ii) N-hydroxysuccinimide-terminated disulfide surfaces. The properties of the monolayers, with and without attached receptor probe molecules, were analysed using infrared spectroscopy, ellipsometry, fluorescence scanning and atomic force microscopy. Several experimental parameters, such as condensation reagents, additives, probe and target concentrations and immobilization time, were systematically varied to determine the dynamic range and to optimize the sensitivity and signal-to-noise ratio of the biochip platforms. Fluorescence screening using Cy5-labelled antigens finally demonstrated that both surfaces could be successfully employed to immobilize the antibodies. The pros and cons of the two approaches are also discussed.Received November 15, 2002; accepted March 25, 2003Published online July 28, 2003 |
