LAUSR

Abstract Two nanoprobes based on gold nanoparticles (AuNPs) and magnetic nanoparticles (MNPs) were synthesized, respectively. A double- nanoprobe based immunoassay with sensitivity, rapidity, and reproducibility was developed for the determination of phenanthrene (Phe) and related low-mass polycyclic aromatic hydrocarbons (PAHs) in water samples. The AuNPs probe was used as signal amplification probe, which can improve the sensitivity of the immunoassay. The MNPs probe was used as immobilization of Phe, which can lead to speed up reaction of antigen-antibody by the suspension property and dispersed nature. The linear range and the limit of detection (LOD) were 0.14–6.55 ng/mL and 0.08 ng/mL, respectively. Compared with the traditional ELISA, the sensitivity of the double-probe based immunoassay was improved about 30 times and the time for determination was shorten 104 min. The recoveries of Phe and related low-mas PAHs from tap water, contaminated water and river water were 90.5–109.8%, 91.2–108.0% and 93.0–107.8%, respectively. The correlation coefficient of the results between the developed immunoassay and GC–MS/MS was 0.9977. The developed double- nanoprobe based immunoassay was sensitive, rapid and good reproducibility for the determination of Phe and related low-mas PAHs in environmental water.