▎ 摘　　要

Clays (C) such as sepiolite (SEP) or bentonite (BEN) and their mixtures with graphene (G) have been used as sorbents in dispersive solid phase extraction (dSPE). Tryptophan (TRP) analysis by fluorescence combined with a sample preparation step using G/C 30/70 w/w mixture provides a quantitative TRP retention, independently of the amino acid concentration with a desorption process feasible in 80 mM aqueous solution of the surfactant Brij L23. Under these conditions, the detection and quantification limits are 3.5 and 11.8 mu g L-1, respectively. Additionally, a novel, simple and inexpensive method has been developed to directly analyse TRP in real sam-ples, in which the presence of matrix interferents typically limits to obtain accurate results. For the first time, BEN has been used as an effective clean-up sorbent for the fluorimetric analysis of TRP in beer, leading to results without statistical differences versus those of a reference HPLC method free of interferences, with recoveries of 90 % and 100 %. The proposed method can be applied to accurately analyse TRP in complex matrices in a direct, easy, fast and sustainable way.