The separation of amino compounds by supercritical fluid chromatography (SFC) is a difficult problem to solve, owing to the apolar nature of CO2. The derivatization of amino functions with the 9-fluorenylmethyl chloroformate (FMOC-Cl) allows to obtain apolar UV-absorbing compounds easily eluted with a supercritical mobile phase. Optimization of derivatization parameters allows us to analyze quantitatively amphetamines and catecholamines. These compounds can be separated in less than 5 min with a small addition of methanol as polar modifier. The total procedure takes no more than 15 min and can be automatized to gain time. As presented in this study, this method can be employed to physiological fluids as urine.