Laser fluorimetry for capillary column liquid chromatography: high-sensitivity detection of derivatized biological...

A high-sensitivity, low-dead-volume laser-induced fluorescence detector has been designed for use in capillary column liquid chromatography. This detector exhibits femtogram detection limits and a linear dynamic range spanning five orders of magnitude. Derivatization schemes were utilized to add a fluorescent moiety to biologically important compounds such that their excitation maxima corresponded well with the output wavelength of the laser. Sample chromatograms are presented for picogram amounts of standard bile acid and steroid hormone derivatives. In addition, a high-efficiency separation of picogram amounts of the solvolyzable steroid hormones from human serum is illustrated.