AVS 51st International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI-MoP

Paper BI-MoP10
Microfluidic Circuit Fabrication and Packaging for Surface-Controlled Bioprocesses in BioMEMS

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: J.J. Park, University of Maryland
Authors: T.M. Valentine, University of Maryland
J.J. Park, University of Maryland
G.W. Rubloff, University of Maryland
R. Ghodssi, University of Maryland
Correspondent: Click to Email
We have previously demonstrated that biopolymers (specifically, the polysaccharide chitosan) can be deposited in vitro at patterned, voltage-programmed electrodes, and that subsequent coupling and conjugation of biomolecules (proteins, nucleic acids) opens the door to applications such as bioassays and enzymatic catalysis. To extend these capabilities beyond simple devices to more complex bioMEMS systems, robust means for microfluidic circuit fabrication and packaging are required. We have designed and fabricated microfluidic networks to support combinatorial test site libraries for surface-controlled bioprocesses, along with packaging approaches to control fluidics and electrical inputs/outputs to the bioMEMS systems, with emphasis on robust technologies for leak-free microfluidics, use of polymer-based MEMS, incorporation of electrode structures and optical access to them, and reliable exchange of bioMEMS systems through reusable packaging which allows rapid connection of fluid and electrical inputs/outputs to external control systems. Three different approaches to microfluidic design, based on both sealing and bonding, are promising in concert with the packaging strategy. The efficacy of these fabrication and packaging approaches is demonstrated through results on fluidic sealing and on the electrically programmable deposition of NHS-fluorescein labeled chitosan at internal sites in the bioMEMS system. The impact of flow rates and residence times on biopolymer deposition and biomolecular conjugation reflect key chemical engineering questions associated with surface bioreactions in microfluidic systems, laying the groundwork for future applications in miniaturized bio-reactors and chemical and biological sensors.