title: Thermoplastic microfluidic platform for single-molecule detection, cell culture, and actuation.
abstract: We have developed a multipurpose microfluidic platform that allows for sensitive fluorescence detection on inexpensive disposable chips. The fabrication scheme involves rapid injection molding of thermoplastics, followed by silica deposition and covalent attachment of an unstructured flexible lid. This combines the virtues of elastomer technology with high-throughput compact disk injection molding. Using this technique, the time to produce 100 chips using a single master can be lowered from more than 1 week by standard PDMS technologies to only a couple hours. The optical properties of the fabricated chips were evaluated by studying individual fluorescence-labeled DNA molecules in a microchannel. Concatemeric DNA molecules were generated through rolling circle replication of circular DNA molecules, which were labeled by hybridization of fluorescence-tagged oligonucleotides. Rolling circle products (RCPs) were detected after as little as 5 min of DNA polymerization, and the RCPs in solution showed no tendency for aggregation. To illustrate the versatility of the platform, we demonstrate two additional applications: The flexible property of the lid was used to create a peristaltic pump generating a flow rate of 9 nL/s. Biocompatibility of the platform was illustrated by culturing Chinese hamster ovary cells for 7 days in the microfluidic channels.
authors.affiliation: Beijer Laboratory, Department of Genetics and Pathology, Rudbeck Laboratory, Angstrom Laboratory, University of Uppsala, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Melin
authors.forename: Henrik
authors.initials: H
authors.lastname: Johansson
authors.forename: Ola
authors.initials: O
authors.lastname: Söderberg
authors.forename: Fredrik
authors.initials: F
authors.lastname: Nikolajeff
authors.forename: Ulf
authors.initials: U
authors.lastname: Landegren
authors.forename: Mats
authors.initials: M
authors.lastname: Nilsson
authors.forename: Jonas
authors.initials: J
authors.lastname: Jarvius
mesh_terms: D000818:Animals; D016466:CHO Cells; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods*; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000032:analysis; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D018625:Microscopy, Atomic Force; D013696:Temperature
chemical_list: D004247:DNA