Volume-amplified magnetic bioassay integrated with microfluidic sample handling and high-Tc SQUID magnetic readout
Journal article, 2018
A bioassay based on a high-Tc superconducting quantum interference device (SQUID) reading out functionalized magnetic nanoparticles (fMNPs) in a prototype microfluidic platform is presented. The target molecule recognition is based on volume amplification using padlock-probe-ligation followed by rolling circle amplification (RCA). The MNPs are functionalized with single-stranded oligonucleotides, which give a specific binding of the MNPs to the large RCA coil product, resulting in a large change in the amplitude of the imaginary part of the ac magnetic susceptibility. The RCA products from amplification of synthetic Vibrio cholera target DNA were investigated using our SQUID ac susceptibility system in microfluidic channel with an equivalent sample volume of 3 μl. From extrapolation of the linear dependence of the SQUID signal versus concentration of the RCA coils, it is found that the projected limit of detection for our system is about 1.0 e5 RCA coils (0.2e−18 mol), which is equivalent to 66 fM in the 3 μl sample volume. This ultra-high magnetic sensitivity and integration with microfluidic sample handling are critical steps towards magnetic bioassays for rapid detection of DNA and RNA targets at the point of care.
POC
high-Tc SQUID
microfluidics
superconductivity
Bioassay
Author
Sobhan Sepehri
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Emil Eriksson
RISE Research Institutes of Sweden
Alexei Kalaboukhov
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Teresa Zardán Gómez de la Torre
Uppsala University
Kiryl Kustanovich
Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry
Aldo Jesorka
Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry
Justin Schneiderman
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
MedTech West
Jakob Blomgren
RISE Research Institutes of Sweden
Christer Johansson
RISE Research Institutes of Sweden
Maria Strømme
Uppsala University
Dag Winkler
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
APL Bioengineering
24732877 (eISSN)
Vol. 2 1 016102Point-of care Influenza Diagnostics FLU-ID
Swedish Foundation for Strategic Research (SSF) (SBE13-0125), 2021-01-01 -- 2021-03-31.
Swedish Foundation for Strategic Research (SSF) (SBE13-0125), 2014-06-01 -- 2020-12-31.
Areas of Advance
Nanoscience and Nanotechnology
Life Science Engineering (2010-2018)
Subject Categories
Biochemistry and Molecular Biology
Analytical Chemistry
Other Physics Topics
Medical Biotechnology
Nano Technology
Nano Technology
Other Industrial Biotechnology
Roots
Basic sciences
Infrastructure
Nanofabrication Laboratory
DOI
10.1063/1.4999713