Detection and manipulation of biomolecules by magnetic carriers.

Department of Physics, University of Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany.
Journal of Biotechnology (Impact Factor: 3.18). 09/2004; 112(1-2):25-33. DOI: 10.1016/j.jbiotec.2004.04.018
Source: PubMed

ABSTRACT The detection and manipulation of single molecules on a common platform would be of great interest for basic research of biological or chemical systems. A promising approach is the application of magnetic carriers. The principles are demonstrated in this contribution. It is shown that paramagnetic beads can be detected by highly sensitive magnetoresistive sensors yielding a purely electronic signal. Different configurations are discussed. The capability of the sensors to detect even single markers is demonstrated by a model experiment. In addition, the paramagnetic beads can be used as carriers for biomolecules. They can be manipulated on-chip via currents running through specially designed line patterns. Thus, magnetic markers in combination with magnetoresistive sensors are a promising choice for future integrated lab-on-a-chip systems.

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