Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5491148 | Journal of Magnetism and Magnetic Materials | 2017 | 5 Pages |
Abstract
We use functionalized iron oxide magnetic multi-core particles of 100 nm in size (hydrodynamic particle diameter) and AC susceptometry (ACS) methods to measure the binding reactions between the magnetic nanoparticles (MNPs) and bio-analyte products produced from DNA segments using the rolling circle amplification (RCA) method. We use sensitive induction detection techniques in order to measure the ACS response. The DNA is amplified via RCA to generate RCA coils with a specific size that is dependent on the amplification time. After about 75 min of amplification we obtain an average RCA coil diameter of about 1 µm. We determine a theoretical limit of detection (LOD) in the range of 11 attomole (corresponding to an analyte concentration of 55 fM for a sample volume of 200 µL) from the ACS dynamic response after the MNPs have bound to the RCA coils and the measured ACS readout noise. We also discuss further possible improvements of the LOD.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Fredrik Ahrentorp, Jakob Blomgren, Christian Jonasson, Anna Sarwe, Sobhan Sepehri, Emil Eriksson, Alexei Kalaboukhov, Aldo Jesorka, Dag Winkler, Justin F. Schneiderman, Mats Nilsson, Jan Albert, Teresa Zardán Gómez de la Torre, Maria Strømme,