An HPLC detector was modified to operate as a low pressure on-line supercritical fluid extraction detector. Spectra of CO2and fluorene are presented of pressures ranging from 85 to 150 atm. Both the intensity and emission wavelength of fluorene were effected by CO2pressure. As pressure increased, the emission intensity also increased and the emission shifted to a shorter wavelength. The intensity of CO2emission decreased by increasing pressure. The emission wavelength of CO2was unaffected by pressure. A detection limit for fluorene was found to be 5 μg per extraction. The minimal detectable mass was 25 μg (± 8% RSD) per extraction.