title: Handling and detection of 0.8 amol of a near-infrared cyanine dye by capillary electrophoresis with laser-induced fluorescence detection.
abstract: We are interested in the detection of DNA adducts and other trace analytes by labeling them with a fluorescent tag followed by use of capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) for high resolution and sensitivity. Towards this goal, here we report the following: (1) synthesis and handling properties of a near-IR, carboxyl-substituted heptamethine cyanine dye; (2) modification of an existing ball lens LIF detector to provide near-LIF detection with excitation at 785 nm for CE; and (3) corresponding handling and detection of as little as 0.8 amol of the dye by enrich-injection of 4.7 microl of 1 x 10(-13) mol/l dye in methanol from an 8-microl volume into a corresponding CE-LIF system. The electrolyte for the separation was methanol-40 mmol/l aqueous sodium borate (98:2, v/v). This finding encourages further exploration of the dye by functionalization of its carboxyl group for chemical labeling purposes.
authors.affiliation: Department of Pharmaceutical Sciences at the Bouve College of Health Sciences, Northeastern University, Boston, MA 02115, USA.
authors.forename: Changming
authors.initials: C
authors.lastname: Yang
authors.forename: Olga
authors.initials: O
authors.lastname: Shimelis
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Zhou
authors.forename: Guoding
authors.initials: G
authors.lastname: Li
authors.forename: Christophe
authors.initials: C
authors.lastname: Bayle
authors.forename: Michel
authors.initials: M
authors.lastname: Nertz
authors.forename: Hyeran
authors.initials: H
authors.lastname: Lee
authors.forename: Lucjan
authors.initials: L
authors.lastname: Strekowski
authors.forename: Gabor
authors.initials: G
authors.lastname: Patonay
authors.forename: Francois
authors.initials: F
authors.lastname: Couderc
authors.forename: Roger W
authors.initials: RW
authors.lastname: Giese
mesh_terms: D002232:Carbocyanines / Q000032:analysis*; D004396:Coloring Agents / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000379:methods*; D007834:Lasers; D009682:Magnetic Resonance Spectroscopy; D013050:Spectrometry, Fluorescence / Q000379:methods*; D019265:Spectroscopy, Near-Infrared
chemical_list: D002232:Carbocyanines; D004396:Coloring Agents