Fabrication of a Novel Atrazine Biosensor and Its Subpart-per-Trillion Levels Sensitive Performance

The present study describes an atrazine biosensor with the detection limit of 0.1 part-per-trillion (ppt). The atrazine biosensor is fabricated on tyrosinase-immobilized vertical growth TiO2 nanotubes (Tyr/TiO2-NTs), based on the inhibition of tyrosinase by atrazine. The designed Tyr/TiO2-NTs present excellent applicability in atrazine determination, with high sensitivity and stability, and rapid response. The outstanding sensing characteristics for atrazine is attributed to the appropriate bioelectrochemical interface of Tyr/TiO2-NTs, resulting from the preponderant tubular structure, excellent biocompatibility, and hydrophilicity of TiO2-NTs. The atrazine biosensor possesses a wide detection range from 0.2 ppt to 2 part-per-billion (ppb). The practical application of the biosensor is realized for the determination of atrazine and the analysis of its transport in soil samples. A new method for determination of atrazine in soil samples is thus established, which greatly simplifies the preparation procedure of sample and is helpful to evaluate the pollution risk of atrazine to soil, groundwater, and surface water.