Category: Micro- and Nanotechnologies
Existing strategies for lab-scale prototyping of microfluidic chips such as soft lithography, 3D printing, and micromachining are limited in their materials compatibility, scalability, and ease of integration with electronics. This limits commercialization by requiring extensive redesign of prototypes to comply with manufacturing requirements. In addition, limited ability to integrate electronics has encouraged designers of microfluidic chips to rely on bulky off-chip optical and pneumatic systems for sensing and actuation instead of more easily miniaturizable electronic systems. We have developed an inexpensive and simple approach which allows laboratory prototyping of microfluidic chips with integrated microelectrodes in thermoplastics using equipment no more complex or expensive than that used for PDMS soft-lithography. The process is compatible with any thermoplastic material, including polycarbonate, PMMA, and polystyrene. Electrodes are patterned and deposited by way of a modified hot embossing process, followed by an in-situ electrode deformation step which allows for patterning multiple layers of electronics in contact with the channel. This makes it possible to achieve electrode geometries which are difficult or impossible using other prototyping methods, such as parallel-plate electrodes for use in impedance cytometry. Several proofs of concept on-chip sensing and actuation have been demonstrated including impedance sensors and electrolysis pumps. This process represents a manufacturing-friendly approach to laboratory prototyping of microfluidic devices with active, on-chip fluid control and sample readout.
Marc Chooljian– Graduate Student Researcher, University of California, Berkeley, Albany, CA
Graduate Student Researcher
University of California, Berkeley
Graduate student conducting research on fabrication methods for microfluidic devices in Dorian Liepmann's lab at UC Berkeley. B. S. Bioengineering, UC Berkeley, 2009-2013. Ph.D. Bioengineering, UC Berkeley and UCSF Graduate Group, 2013-present.