title: A low pressure on-chip injection strategy for high-performance chip-based chromatography.
abstract: A microfluidic device for high-performance liquid chromatography is presented. The borosilicate glass chip includes a common cross-channel injector and a column chamber. The column chamber comprises two constrictions (10 μm) to retain the chromatographic particles via the keystone effect. A packing channel was utilized to introduce the particulate material (3-μm). This channel has been sealed permanently via laser-assisted photopolymerization avoiding dead volumes within the chromatographic pathway. A sampling strategy is presented enabling the directed definition of the sample plug on-chip. The injection process is studied via video microscopy and chromatographic separations of test solutes with fluorescence detection. Our approach, based on on-chip flow splitting, allows the usage of traditional, economic and robust HPLC instrumentation avoiding the need for sophisticated nano-flow equipment. The performance of the chip device and the injection process was demonstrated by reversed-phase chromatographic separations of a mixture of polycyclic aromatic hydrocarbons achieving constant high efficiencies for the chromatographic signals over the whole elution window.
authors.affiliation: Institute of Analytical Chemistry, University of Leipzig, Linnéstraße 3, 04103 Leipzig, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Thurmann
authors.affiliation: Institute of Analytical Chemistry, University of Leipzig, Linnéstraße 3, 04103 Leipzig, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Dittmar
authors.affiliation: Institute of Analytical Chemistry, University of Leipzig, Linnéstraße 3, 04103 Leipzig, Germany. Electronic address: Belder@uni-leipzig.de.
authors.forename: D
authors.initials: D
authors.lastname: Belder
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D011084:Polycyclic Aromatic Hydrocarbons / Q000302:isolation & purification; D011312:Pressure
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons
keywords: Chip-chromatography; Fluorescence; Injection; Microfluidics; Miniaturization; PAH