title: Packing density, permeability, and separation efficiency of packed microchips at different particle-aspect ratios.
abstract: HPLC microchips are investigated experimentally with respect to packing density, pressure drop-flow rate relation, hydraulic permeability, and separation efficiency. The prototype microchips provide minimal dead volume, on-chip UV detection, and a 75 mm long separation channel with a ca. 50 microm x 75 microm trapezoidal cross-section. A custom-built stainless-steel holder allowed to adopt optimized packing conditions. Separation channels were slurry-packed with 3, 5, and 10 microm-sized spherical, porous C8-silica particles. Differences in interparticle porosity, permeability, and plate height data are analyzed and consistently explained by different microchannel-to-particle size (particle-aspect) ratios and particle size distributions.
authors.affiliation: Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35032 Marburg, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Jung
authors.forename: Steffen
authors.initials: S
authors.lastname: Ehlert
authors.forename: Jose-Angel
authors.initials: JA
authors.lastname: Mora
authors.forename: Karsten
authors.initials: K
authors.lastname: Kraiczek
authors.forename: Monika
authors.initials: M
authors.lastname: Dittmann
authors.forename: Gerard P
authors.initials: GP
authors.lastname: Rozing
authors.forename: Ulrich
authors.initials: U
authors.lastname: Tallarek
mesh_terms: D000465:Algorithms; D055598:Chemical Phenomena; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation*; D007094:Imides / Q000737:chemistry; D016014:Linear Models; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D010539:Permeability; D016062:Porosity; D012822:Silicon Dioxide
chemical_list: D007094:Imides; D012822:Silicon Dioxide