title: Magnetic Dynabeads detection by sensitive element based on giant magnetoimpedance.
abstract: A GMI-biosensor prototype was designed and fabricated using an amorphous ribbon. As a first step, a GMI response was measured with a model liquid media: suspension containing magnetisable Dynabeads M-450. These beads can be used as biomolecular labels when coated with a specific antibody. The GMI change caused by their presence was measured with a biosensor prototype designed with a measuring cell containing an amorphous CoFeMoSiB-ribbon element. GMI was measured at a range of current frequencies from 0.3 to 10 MHz and at intensities of either Irms=3 or 4.5 mA. Commercial Dynabeads M-450 were supplied as a suspension in a phosphate buffered saline. A maximum difference of 25% in the GMI ratio measured with and without Dynabeads was obtained at a frequency of 3.5 MHz and Irms=3 mA. Some potential applications for GMI-biosensor and further directions are proposed.
authors.affiliation: Depto. de Física, Universidad de Oviedo, Avda. Calvo Sotelo s/n, 33007 Oviedo, Spain. galina@uniovi.es
authors.forename: Galina
authors.initials: G
authors.lastname: Kurlyandskaya
authors.forename: Vladimir
authors.initials: V
authors.lastname: Levit
mesh_terms: D017097:Electric Impedance; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D008280:Magnetics; D008863:Microspheres; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity