title: Mixed-mode electrokinetic and chromatographic peptide separations in a microvalve-integrated polymer chip.
abstract: A cycloolefin polymer chip supporting the concatenation of isoelectric focusing (IEF) and reversed-phase liquid chromatography (RPLC) is demonstrated for high throughput two dimensional peptide separations. A unique benefit of the mixed-mode platform is the ability of IEF to act as a highly concentrating electrokinetic separation mode for effective isolation of sample components prior to RPLC. The thermoplastic chip contains integrated high pressure microvalves, enabling uniform sample transfer from the IEF channel to multiple parallel RPLC channels, gradient elution from each RPLC column, and hydrodynamic isolation between the separation dimensions. The reusable system is shown to provide efficient 2-D separations together with facile interfacing with MALDI-MS, suggesting a new path towards effective peptide analysis from complex samples.
authors.affiliation: Department of Mechanical Engineering, University of Maryland, College Park, MD, USA.
authors.forename: Jikun
authors.initials: J
authors.lastname: Liu
authors.forename: Chien-Fu
authors.initials: CF
authors.lastname: Chen
authors.forename: Shuang
authors.initials: S
authors.lastname: Yang
authors.forename: Chien-Cheng
authors.initials: CC
authors.lastname: Chang
authors.forename: Don L
authors.initials: DL
authors.lastname: Devoe
mesh_terms: D000818:Animals; D002417:Cattle; D056148:Chromatography, Reverse-Phase / Q000295:instrumentation* / Q000379:methods; D003516:Cycloparaffins / Q000737:chemistry*; D045304:Cytochromes c / Q000737:chemistry / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D007525:Isoelectric Focusing / Q000295:instrumentation* / Q000379:methods; D056656:Lab-On-A-Chip Devices; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification*; D018892:Proton-Motive Force; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D003516:Cycloparaffins; D010446:Peptide Fragments; C039217:fluorescein isothiocyanate bovine serum albumin; D012710:Serum Albumin, Bovine; D045304:Cytochromes c; D016650:Fluorescein-5-isothiocyanate