Charge-coupled device based fluorescence detection in capillary electrophoresis

Abstract Capillary electrophoresis (CE) is currently one of the highest efficiency small volume separation methods available, and laser induced fluorescence (LIF) detection the most sensitive CE detection method. The design and characteristics of a unique charge-coupled device based CE/LIF system are described that acquires simultaneous fluorescence emission spectra from components separated by CE. The limit of detection for this multichannel detection system is below 10-13 M (less than 100 molecules) for sulforhodamine 101. The advantages of obtaining the wavelength resolved data as opposed to more conventional single channel data are outlined. Two methods for enhancing the ability to attach a fluorescent tag to low concentration peptide samples are presented, including the fabrication of a preconcentrator/reactor at the inlet tip of the capillary and the use of a UV laser with the fluorogenic derivatising agent fluorescamine.