title: New valve and bonding designs for microfluidic biochips containing proteins.
abstract: Two major concerns in the design and fabrication of microfluidic biochips are protein binding on the channel surface and protein denaturing during device assembly. In this paper, we describe new methods to solve these problems. A "fishbone" microvalve design based on the concept of superhydrophobicity was developed to replace the capillary valve in applications where the chip surface requires protein blocking to prevent nonspecific binding. Our experimental results show that the valve functions well in a CD-like ELISA device. The packaging of biochips containing pre-loaded proteins is also a challenging task since conventional sealing methods often require the use of high temperatures, electric voltages, or organic solvents that are detrimental to the protein activity. Using CO2 gas to enhance the diffusion of polymer molecules near the device surface can result in good bonding at low temperatures and low pressure. This bonding method has little influence on the activity of the pre-loaded proteins after bonding.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Nanoscale Science and Engineering Center for Affordable Nanoengineering of Polymeric Biomedical Devices, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Chunmeng
authors.initials: C
authors.lastname: Lu
authors.forename: Yubing
authors.initials: Y
authors.lastname: Xie
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
authors.forename: Mark M-C
authors.initials: MM
authors.lastname: Cheng
authors.forename: Chee-Guan
authors.initials: CG
authors.lastname: Koh
authors.forename: Yunling
authors.initials: Y
authors.lastname: Bai
authors.forename: L James
authors.initials: LJ
authors.lastname: Lee
authors.forename: Yi-Je
authors.initials: YJ
authors.lastname: Juang
mesh_terms: D000327:Adsorption; D004797:Enzyme-Linked Immunosorbent Assay; D004867:Equipment Design; D057927:Hydrophobic and Hydrophilic Interactions; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D011506:Proteins
chemical_list: D011506:Proteins