Small-particle silica gels have been used as an adsorbent for high-speed liquid chromatography in an investigation of the application of fluorigenic labelling for the analysis of aromatic hydroxy compounds. The test compounds were mono- and dihydroxybiphenyls and the fluorigenic agent was dansyl chloride. Fluorescence and UV detection are compared. Calibration curves are linear and the relative standard deviation for ten concentrations (1 – 250 ng) is 1.0 ± 0.5% for peak height and 1% or less for peak area. Spiked urine samples were investigated to test this method.