Towards an electrowetting-based digital microfluidic platform for magnetic immunoassays.
Journal: Lab On A Chip
Published:
Abstract
We demonstrate ElectroWetting-On-Dielectric (EWOD) transport and SQUID gradiometer detection of magnetic nanoparticles (MNPs) suspended in a 2 microl de-ionized water droplet. This proof-of-concept methodology constitutes the first development step towards a highly sensitive magnetic immunoassay platform with SQUID readout and droplet-based sample handling. Magnetic AC-susceptibility measurements were performed on MNPs with a hydrodynamic diameter of 100 nm using a high-Tc dc Superconducting Quantum Interference Device (SQUID) gradiometer as detector. We observed that the signal amplitude per unit volume is 2.5 times higher for a 2 microl sample droplet compared to a 30 microl sample volume.
Authors
Vincent Schaller, Anke Sanz Velasco, Alexey Kalabukhov, Justin Schneiderman, Fredrik Oisjöen, Aldo Jesorka, Andrea Astalan, Anatol Krozer, Cristina Rusu, Peter Enoksson, Dag Winkler