A label-free and selective electrochemical aptasensor for ultrasensitive detection of Di(2-ethylhexyl) phthalate based on self-assembled DNA nanostructure amplification

•An electrochemical aptasensor was constructed to detect Di(2-ethylhexyl) phthalate.•The aptasensor has the advantages of easy operation, label-free and low cost.•Utilizing self-assembly of DNA nanostructures for amplifying detection signal.•The aptasensor shows wide linear range and low detection limit of 0.04 ng mL−1.•The aptasensor shows good reproducibility and high selectivity for DEHP assay.