A new reversed-phase/strong anion-exchange mixed-mode stationary phase based on polar-copolymerized approach and its application in the enrichment of aristolochic acids

► A C18SAX stationary phase was synthesized based on polar-copolymerized approach. ► The mixed-mode C18SAX material could be used both in SPE and HPLC. ► The SPE method was efficiently developed on the basis of HPLC evaluation. ► Aristolochic acids were enriched with high selectivity from complex matrices. ► The C18SAX material has great potential in the enrichment of acidic compounds.