title: A chip-based capillary electrophoresis-contactless conductivity microsystem for fast measurements of low-explosive ionic components.
abstract: A miniaturized analytical system for separating and detecting inorganic explosive residues, based on the coupling of a micromachined capillary electrophoresis (CE) chip with a contactless conductivity detector is described. The low electroosmotic flow (EOF) of the poly(methylmethacrylate) (PMMA) chip material facilitates the rapid switching between analyses of cations and anions using the same microchannel and run buffer (and without an EOF modifier), and hence offers rapid (< 1 min) measurement of seven explosive-related cations and anions. Experimental parameters relevant to the separation and detection processes have been optimized. Addition of a 18-crown-6 ether modifier has been used for separating the peaks of co-migrating potassium and ammonium ions. The ionic-explosive microchip system combines the distinct advantages of contactless conductivity detection with the attractive features of plastic CE microchips. The new microsystem offers great promise for monitoring explosive-related ions at the sample source, with significant advantages of speed/warning, efficiency, cost, or sample size.
authors.affiliation: Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces 88003, USA. joewang@nmsu.edu
authors.forename: Joseph
authors.initials: J
authors.lastname: Wang
authors.forename: Martin
authors.initials: M
authors.lastname: Pumera
authors.forename: Greg
authors.initials: G
authors.lastname: Collins
authors.forename: Frantisek
authors.initials: F
authors.lastname: Opekar
authors.forename: Ivan
authors.initials: I
authors.lastname: Jelínek
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods*; D007477:Ions / Q000032:analysis*; D023481:Terrorism
chemical_list: D007477:Ions