Digital Microfluidics Assisted Sealing of Individual Magnetic Particles in Femtoliter-Sized Reaction Wells for Single-Molecule Detection
Digital microfluidics has emerged in the last years as a promising liquid handling technology for a variety of applications. Here, we describe in detail how to build up an electrowetting-on-dielectric-based digital microfluidic chip with unique advantages for performing single-molecule detection. We illustrate how superparamagnetic particles can be printed with very high loading efficiency (over 98 %) and single-particle resolution in the microwell array patterned in the Teflon-AF® surface of the grounding plate of the chip. Finally, the potential of the device for its application to single-molecule detection is demonstrated by the ultrasensitive detection of the biotinylated enzyme β-Galactosidase captured on streptavidin-coated particles in the described platform.
Key wordsDigital Microfluidics Microwell Array Magnetic Particles Single-Molecule Detection Digital Bioassays
This research was financially supported by the KU Leuven Research Council (IDO-project 10/012, OT project 13/058 and Atheromix IOF-knowledge platform), the Agency for Innovation by Science and Technology in Flanders (IWT project 121615), and the Fund for Scientific Research Flanders—FWO (G.0997.11 and G.0861.14).
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