Biotin-streptavidin-amplified real-time immune-PCR assay for detecting dimethyl phthalate in beverage and drinking water samples

Dimethyl phthalate (DMP), one family of the phthalic acid diesters (PAEs), is an increasing widely used plasticizer. A sensitive and high-throughput direct competitive biotin-streptavidin-amplified system based on real-time immune-PCR (BA-rt-IPCR) techniques was developed for detecting DMP in beverage and drinking water samples. In our assay, we selected dimethyl 4-aminophthalate as the optimal DMP hapten to prepare high titer of rabbit polyclonal anti-DMP antibodies (pAb-DMP). Under the optimized conditions, the proposed method was used to detect DMP with a linearity range from 10 to 100 ng L-1, and the limit of detection (LOD) was 1.98 pg L-1. Finally, the results about DMP in beverage and drinking water samples were consistent with those using gas chromatography-mass spectrometry (GC-MS), which proved that the proposed immunoassay for detecting DMP in the environment was accurate, reliably rapid, and receptive.