Yang Changming, Shimelis Olga, Zhou Xiaojuan, Li Guoding, Bayle Christophe, Nertz Michel, Lee Hyeran, Strekowski Lucjan, Patonay Gabor, Couderc Francois, Giese Roger W
Department of Pharmaceutical Sciences at the Bouve College of Health Sciences, Northeastern University, Boston, MA 02115, USA.
J Chromatogr A. 2002 Dec 6;979(1-2):307-14. doi: 10.1016/s0021-9673(02)01441-3.
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.
