Strong interest in new fabrication method for micro-fluidics
"Beyond PDMS: off-stoichiometry thiol–ene (OSTE) based soft lithography for rapid prototyping of microfluidic devices" by researchers at The Microsystem technology lab and the Division of Coating Technology, Fibre and Polymer Technology at KTH was among the most downloaded papers in the Lab on a chip journal in September.
The article by Carl Fredrik Carlborg, Tommy Haraldsson, Kim Öberg, Michael Malkoch and Wouter van der Wijngaart was the 4th most downloaded article in the Journal during September.
Lab Chip, 2011, 11, 3136-3147. DOI: 10.1039/C1LC20388F
Abstract
In this article we introduce a novel polymer platform based on off-stoichiometry thiol–enes (OSTEs), aiming to bridge the gap between research prototyping and commercial production of microfluidic devices. The polymers are based on the versatile UV-curable thiol–ene chemistry but takes advantage of off-stoichiometry ratios to enable important features for a prototyping system, such as one-step surface modifications, tuneable mechanical properties and leakage free sealing through direct UV-bonding. The platform exhibits many similarities with PDMS, such as rapid prototyping and uncomplicated processing but can at the same time mirror the mechanical and chemical properties of both PDMS as well as commercial grade thermoplastics. The OSTE-prepolymer can be cast using standard SU-8 on silicon masters and a table-top UV-lamp, the surface modifications are precisely grafted using a stencil mask and the bonding requires only a single UV-exposure. To illustrate the potential of the material we demonstrate key concepts important in microfluidic chip fabrication such as patterned surface modifications for hydrophobic stops, pneumatic valves using UV-lamination of stiff and rubbery materials as well as micromachining of chip-to-world connectors in the OSTE-materials.
