title: Poly(ethylene glycol)-functionalized devices for electric field gradient focusing.
abstract: Electric field gradient focusing (EFGF) is an equilibrium gradient focusing technique that depends on an electric field gradient and a hydrodynamic counterflow to focus, concentrate, and separate charged analytes. In this work, EFGF devices were fabricated from poly(ethylene glycol) (PEG)-functionalized acrylic plastic. The separation channel was formed in an ionically conductive and protein-resistant PEG-functionalized hydrogel, which was cast in a changing cross-sectional cavity in the plastic device. A linear electric field gradient was obtained by applying a voltage lengthwise across the shaped hydrogel. Standard proteins were used as analytes to demonstrate the performance of these EFGF devices. With an increase in counterflow rate or decrease in applied voltage, analyte bands broadened, but resolution increased in agreement with theory. To reduce analyte band dispersion and improve focusing performance, a protein-compatible PEG-functionalized monolith was incorporated in the EFGF channel. Compared with focusing in an open channel, protein bands in the monolith-filled EFGF channel were significantly narrower.
authors: Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA.
authors: Xuefei
authors: X
authors: Sun
authors: Paul B
authors: PB
authors: Farnsworth
authors: Adam T
authors: AT
authors: Woolley
authors: H Dennis
authors: HD
authors: Tolley
authors: Karl F
authors: KF
authors: Warnick
authors: Milton L
authors: ML
authors: Lee
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004574:Electromagnetic Fields; D020100:Hydrogels; D008855:Microscopy, Electron, Scanning; D011092:Polyethylene Glycols / Q000737:chemistry*; D011142:Polyvinyl Alcohol / Q000737:chemistry; D016062:Porosity; D011506:Proteins / Q000737:chemistry
chemical_list: D020100:Hydrogels; D011506:Proteins; D011092:Polyethylene Glycols; D011142:Polyvinyl Alcohol