title: Post-column reactor of coaxial-gap mode for laser-induced fluorescence detection in capillary electrophoresis.
abstract: A post-column reactor with coaxial-gap mode is developed for laser-induced fluorescence detection (LIF) in capillary electrophoresis (CE). The reactor can be assembled simply and conveniently, in which a thin polyimide sleeve of 10-mm length obtained from the capillary coating is used to align separation and reaction capillary with a 20 microm gap. Naphthalene-2,3-dicarboxaldehyde and 2-mercaptoethanol are used as derivatization reagents and delivered into the reaction capillary through the annulus between the separation capillary and polyimide sleeve and the gap of two capillaries by gravity. A reaction distance from the gap to detection point is 5mm. For the post-column reactor of CE-LIF, several configuration parameters are optimized, including liquid level difference between the derivatization solution and outlet buffer, annular dimension between the outer diameter of etched separation capillary and the inner diameter of polyimide sleeve, and reaction distance, etc. The detection limits in the range from 8.0x10(-8) to 1.0x10(-6) mol/L and linear calibration range more than two orders of magnitude are obtained for amino acids. The separation efficiency ranges from 1.35x10(5) to 1.67x10(5) theoretical plates.
authors.affiliation: Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Chang-Zhu
authors.initials: CZ
authors.lastname: Yu
authors.forename: You-Zhao
authors.initials: YZ
authors.lastname: He
authors.forename: Fang
authors.initials: F
authors.lastname: Han
authors.forename: Guo-Ni
authors.initials: GN
authors.lastname: Fu
mesh_terms: D019342:Acetic Acid / Q000032:analysis; D000596:Amino Acids / Q000032:analysis*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D017022:Flow Injection Analysis; D005453:Fluorescence; D007834:Lasers; D012680:Sensitivity and Specificity
chemical_list: D000596:Amino Acids; D019342:Acetic Acid