Novel detection system for biomolecules using nano-sized bacterial magnetic particles and magnetic force microscopy.
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.
Amemiya
Yosuke
Y
Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho Koganei, Tokyo 184-8588, Japan.
Tanaka
Tsuyoshi
T
Yoza
Brandon
B
Matsunaga
Tadashi
T
D001426:Bacterial Proteins / Q000648:ultrastructure; D015415:Biomarkers; D015374:Biosensing Techniques / Q000379:methods*; D001710:Biotin / Q000737:chemistry / Q000378:metabolism; D019921:Biotinylation; D005240:Feasibility Studies; D008280:Magnetics; D042201:Magnetospirillum; D018625:Microscopy, Atomic Force; D008954:Models, Biological; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology; D010316:Particle Size; D011485:Protein Binding; D012680:Sensitivity and Specificity; D019809:Streptavidin / Q000737:chemistry / Q000378:metabolism
D001426:Bacterial Proteins; D015415:Biomarkers; D001710:Biotin; D019809:Streptavidin