title: Lipid-coated microdroplet array for in vitro protein synthesis.
abstract: Monitoring complex biological assays such as in vitro protein synthesis over long periods in micrometer-sized cavities of poly(dimethyl siloxane) (PDMS) microfluidic devices requires a strategy that solves the adsorption and absorption problems on PDMS surfaces. In this study, we developed a technique that instantaneously arrays aqueous microdroplets coated with a phospholipid membrane within a single microfluidic device. The simple lipid bilayer coating effectively inhibits the adsorption of proteins and DNA, whereas the encapsulation of the droplet reduces the area in contact with the PDMS surface, resulting in decreased absorption in part. Although the size becomes smaller during the first few hours, a lipid-coated microdroplet array demonstrated a temporal stability of more than 20 h and a size uniformity of CV 3% in the device. Furthermore, we succeeded in expressing a green fluorescent protein by confining an in vitro translation system in the microdroplets, which was confirmed by scanning the fluorescence spectrum of the droplets, demonstrating that the lipid coat secured the synthetic reaction from the adsorption problem.
authors.affiliation: Kanagawa Academy of Science and Technology, Japan.
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Osaki
authors.forename: Satoko
authors.initials: S
authors.lastname: Yoshizawa
authors.forename: Ryuji
authors.initials: R
authors.lastname: Kawano
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Sasaki
authors.forename: Shoji
authors.initials: S
authors.lastname: Takeuchi
mesh_terms: D000327:Adsorption; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000096:biosynthesis*; D008051:Lipid Bilayers / Q000737:chemistry; D008055:Lipids / Q000737:chemistry*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D010316:Particle Size; D014176:Protein Biosynthesis; D013499:Surface Properties
chemical_list: D004129:Dimethylpolysiloxanes; D008051:Lipid Bilayers; D008055:Lipids; D049452:Green Fluorescent Proteins; C013830:baysilon