Based on the affinity interactions between Cu 2+ metal chelate and -SH groups of aminothiols such as cysteine, a polymer solid-phase extraction (SPE) monolith was designed and synthetized by the tridentate ligand iminodiacetic acid immobilized on the surface of poly glycidyl methacrylate-based monolith and after modification with Cu 2+ . Glutathione as a model compound was tested to evaluate the performance of the SPE monolith, and optimized to the enrichment conditions. Under the optimum conditions, the maximum absorption capacity for glutathione of this polymer SPE monolith was determined at 43.15 mg g −1 , and the polymer monolith was used for the extraction and enrichment of trace aminothiols in human plasma samples.