title: A method for characterizing adsorption of flowing solutes to microfluidic device surfaces.
abstract: We present a method for characterizing the adsorption of solutes in microfluidic devices that is sensitive to both long-lived and transient adsorption and can be applied to a variety of realistic device materials, designs, fabrication methods, and operational parameters. We have characterized the adsorption of two highly adsorbing molecules (FITC-labeled bovine serum albumin (BSA) and rhodamine B) and compared these results to two low adsorbing species of similar molecular weights (FITC-labeled dextran and fluorescein). We have also validated our method by demonstrating that two well-known non-fouling strategies [deposition of the polyethylene oxide (PEO)-like surface coating created by radio-frequency glow discharge plasma deposition (RF-GDPD) of tetraethylene glycol dimethyl ether (tetraglyme, CH(3)O(CH(2)CH(2)O)(4)CH(3)), and blocking with unlabeled BSA] eliminate the characteristic BSA adsorption behavior observed otherwise.
authors.affiliation: Department of Bioengineering, University of Washington, Seattle, WA, USA. khawk@u.washington.edu
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Hawkins
authors.forename: Mark R
authors.initials: MR
authors.lastname: Steedman
authors.forename: Richard R
authors.initials: RR
authors.lastname: Baldwin
authors.forename: Elain
authors.initials: E
authors.lastname: Fu
authors.forename: Sandip
authors.initials: S
authors.lastname: Ghosal
authors.forename: Paul
authors.initials: P
authors.lastname: Yager
mesh_terms: D000327:Adsorption; D001672:Biocompatible Materials / Q000737:chemistry; D002845:Chromatography / Q000379:methods; D004867:Equipment Design; D016650:Fluorescein-5-isothiocyanate / Q000494:pharmacology; D008422:Materials Testing; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods*; D044085:Microfluidics; D012235:Rhodamines / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000378:metabolism; D013499:Surface Properties; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; D012235:Rhodamines; D012710:Serum Albumin, Bovine; D016650:Fluorescein-5-isothiocyanate; C029773:rhodamine B