Sensitive magnetic biodetection using magnetic multi-core nanoparticles and RCA coils
Journal article, 2017
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.
Biodetection
Magnetic multi-core particles
RCA coil
AC susceptometry
Differential induction coil
Magnetic nanoparticles
Author
Fredrik Ahrentorp
Jakob Blomgren
Christian Jonasson
Anna Sarwe
Sobhan Sepehri
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Emil Eriksson
Chalmers, Microtechnology and Nanoscience (MC2)
Alexei Kalaboukhov
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Aldo Jesorka
Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry
Dag Winkler
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Justin Schneiderman
University of Gothenburg and MedTech West
Mats Nilsson
Stockholms universitet
Jan Albert
Karolinska University Hospital
Teresa Zardán Gómez de la Torre
Uppsala Universitet
Maria Strømme
Uppsala Universitet
Christer Johansson
Journal of Magnetism and Magnetic Materials
0304-8853 (ISSN)
Vol. 427 14-18Subject Categories (SSIF 2011)
Analytical Chemistry
DOI
10.1016/j.jmmm.2016.10.041