title: Nonaqueous based microchip separation of toxic metal ions using 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol.
abstract: The colorimetric metal chelating agent, 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol (5-Br-PAPS), was demonstrated on a capillary electrophoresis microchip in the separation and detection of six metal ions of environmental concern, Cd2+, Pb2+, Cu2+, Co2+, Ni2+, and Hg2+. The inclusion of methanol in the buffer was found to improve both the separation efficiency and sensitivity, in addition to making the technique directly amenable to the application of solid-phase extraction. The combination of metal chelation with solid-phase extraction on a C18 silica gel microcolumn gave several hundred fold improvements in detection limits for the CE microchip measurements of toxic metal ions in water and extracted from a solid Plexiglas surface.
authors.affiliation: Nova Research, Inc., 1900 Elkin Street, Suite 230, Alexandria, VA 22308, USA.
authors.forename: Gang
authors.initials: G
authors.lastname: Deng
authors.forename: Greg E
authors.initials: GE
authors.lastname: Collins
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D019075:Electrophoresis, Capillary; D008670:Metals / Q000302:isolation & purification* / Q000633:toxicity; D012666:Semiconductors
chemical_list: D001391:Azo Compounds; D008670:Metals; C034322:2-(5-bromo-2-pyridylazo)-5-(N-n-propyl-N-3-sulfopropylamino)phenol