Detection of atrazine residues in water by magnetic nanoparticles enhanced surface plasmon resonance immunosensor

A signal enhanced immunosensing detection method for atrazine residue in drinking water was established. Magnetic nanoparticles(MNP) were introduced into surface plasmon resonance(SPR) sensing system for signal enhancement. The conjugate of atrazine monoclonal antibodies(AT-mAb) and MNP was used as sensing recognition element. Under the optimized conditions, the minimum detection limit of the established method reached 0.89 ng/mL(S/N=3) with analytical range of 8.62-7.18×103 ng/mL. The detection for one sample could be performed in less than 20 min. Recoveries of spiked samples were found to be between 94% and 102% with RSDs of 5.1%-7.3% at 10-1000 ng/mL. Signal intensity and detection sensitivity of the SPR sensing system were effectively enhanced comparing with that without MNP. Thus, a rapid, sensitive and accurate detection method for atrazine residue in water was established. This technique showed potential use in on-site detection technique and equipments.