Abstract: A capillary electrophoretic system and method for accurate and precise post-column manipulation of molecules separated by capillary electrophoresis is disclosed. The system of the invention includes a separation capillary; a detector positioned close to, and preferably less than approximately one cm from the outlet end of the capillary; and a sheath which surrounds and directs a collection buffer over the capillary outlet end. With the detector positioned as described, precise and accurate correlation is possible between detection of the separated components of a sample and their emergence from the capillary. The detector preferably includes optical fibers connected to a spectrophotometric detection method, such as UV detection or fluorescence, including laser induced fluorescence.