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 016102

Point-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

More information

Latest update

4/21/2023