Send to

Choose Destination
J Biotechnol. 2005 Nov 21;120(3):308-14. Epub 2005 Aug 18.

Novel detection system for biomolecules using nano-sized bacterial magnetic particles and magnetic force microscopy.

Author information

Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho Koganei, Tokyo 184-8588, Japan.


A system for streptavidin detection using biotin conjugated to nano-sized bacterial magnetic particles (BMPs) has been developed. BMPs, isolated from magnetic bacteria, were used as magnetic markers for magnetic force microscopy (MFM) imaging. The magnetic signal was obtained from a single particle using MFM without application of an external magnetic field. The number of biotin conjugated BMPs (biotin-BMPs) bound to streptavidin immobilized on the glass slides increased with streptavidin concentrations up to 100 pg/ml. The minimum streptavidin detection limit using this technique is 1 pg/ml, which is 100 times more sensitive than a conventional fluorescent detection system. This is the first report using single domain nano-sized magnetic particles as magnetic markers for biosensing. This assay system can be used for immunoassay and DNA detection with high sensitivities.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center