A hapten di(2-ethylhexyl) 4-aminophthalate (DEHAP) which possesses the structural feature of di(2-ethylhexyl) phthalate (DEHP) was synthesized via esterification and reduction with 4-nitrophthalic acid and 2-ethyl-1-hexanol. The product was confirmed by infrared absorption spectroscopy (IR), 1H nuclear magnetic resonance spectroscopy (1H NMR) and mass spectrometry (MS). Then glutaraldehyde was used as crosslinker to link DEHAP and bovine serum albumin (BSA) to make artificial immunogen DEHAP-BSA. DEHAP was linked to ovalbumin (OVA) through diazotization to prepare coating antigen DEHAP-OVA. Th...