A Digital‐to‐Channel Microfluidic Interface via Inkjet Printing of Silver and UV Curing of Thiol–Enes. Issue 10 (11th August 2020)

• Record Type: Journal Article
• Authors: Sathyanarayanan, Gowtham; Haapala, Markus; Dixon, Christopher; Wheeler, Aaron R.; Sikanen, Tiina M.
• Is Part Of: Advanced materials technologies. Volume 5:Issue 10(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-08-11
• Subjects: digital microfluidics -- inkjet‐printed electronics -- lab‐on‐a‐chip -- off‐stoichiometric thiol–enes -- replica molding; Materials science -- Periodicals; Technological innovations -- Periodicals; Materials science; Technological innovations; Periodicals; 620.1105
• DOI: 10.1002/admt.202000451
• Languages: English
• ISSNs: 2365-709X

Abstract

Abstract: Microfluidic sample manipulation is a key enabler in modern chemical biology research. Both discrete droplet‐based digital microfluidic (DMF) assays and continuous flow in‐channel assays are well established, each featuring unique advantages from the viewpoint of automation and parallelization. However, there are marked differences in the applicable microfabrication materials and methods, which limit the interfacing of DMF sample preparation with in‐channel separation systems, such as the gold standard microchip electrophoresis. Simultaneously, there is an increasing demand for low‐cost and user‐friendly manufacturing techniques to foster the adaptation of microfluidic technology in routine laboratory analyses. This work demonstrates integration of DMF with in‐channel separation systems using only low‐cost and accessible (non‐cleanroom) manufacturing techniques, i.e., inkjet printing of silver for patterning of the driving electrodes and UV curing of off‐stoichiometric thiol–ene (OSTE) polymers both for dielectric coating of the electrode arrays and replica molding of the microchannel network. As a dielectric, OSTE performs similar to Parylene C (a gold standard dielectric in electrowetting), whereas its tunable surface and bulk properties facilitate straightforward bonding of the microchannel with the dielectric layer. In addition, a new chip design that facilitates efficient droplet transfer from the DMF part to the microchannel inlet solely by electrowetting is showcased. Abstract : A low‐cost, non‐cleanroom manufacturing method and a new microfluidic chip design are introduced for monolithic integration of an in‐channel separation system with a digital microfluidic sample preparation platform. The method employs inkjet printing of silver for patterning of the driving electrodes and UV curing of off‐stoichiometric thiol–ene polymers both for dielectric coating of the electrode arrays and replica molding of the microchannel network.