An automated aflatoxin M1 assay system capable of performing multiple unattended extractions and chromatographic analyses has been developed. A six-axis anthropomorphic laboratory robot and a flexible computer system are combined to operate a sample turntable, a multisolvent dispensing facility, a solid-phase extraction station, a vacuum manifold, an automatic HPLC sample preconcentration unit, an HPLC, a fluorescence detector and a computing integrator. The system is capable of handling bulk milk samples and can determine aflatoxins at the sub-micrograms/kg level with an accuracy and precision comparable to those of the manual methods of analysis. Time of analysis is reduced. The system can be run in an unattended mode of operation.