Determination of tributyltin at parts-per-trillion levels in natural waters by second-order multivariate calibration and fluorescence spectroscopy

► Toxic tributyltin was pre-concentrated on C18 membranes from water samples. ► Excitation-emission fluorescence matrices were measured after morin complexing. ► Multivariate curve resolution was applied for data processing. ► The strong spectral overlapping was resolved by the algorithm. ► Tributyltin traces were quantitated in the presence of uncalibrated interferences.