RecJf exonuclease-catalyzed signal amplified aptasensor for sensitive detection of atrazine using Ni6MnO8@C/Au nanorods and COF@MOF nanohybrids.

Atrazine (ATZ) represents an endocrine-disrupting pesticide posing significant threats to both the environment and human well-being. In this study, a novel turn-on electrochemical aptasensor was successfully developed for highly sensitive ATZ detection. It relied on Ni 6 MnO 8 @C/Au nanorods (Ni 6 MnO 8 @C/AuNR) and covalent-metal organic framework nanohybrids (MCA@Ce-MOF) with RecJ f -catalyzed target recycling amplification. Notably, this marks the first instance of utilizing this strategy for ATZ detection. The substrate material, ultrathin Ni 6 MnO 8 @C/AuNR nanosheets, enhanced the specific surface area, conductivity, and biocompatibility, thereby facilitating biomolecule attachment and improving sensitivity. The scaffolds, hierarchically porous MCA@Ce-MOF, not only elevated the loading efficiency and surface concentration of signal molecules, but also strengthened the binding firmness of biomolecules. RecJ f -catalyzed target recycling was triggered in the presence of ATZ, further magnifying electrochemical signals. Leveraging these unique attributes, the developed aptasensor exhibited exceptional ATZ detection performance with a low detection limit of 4.9 fg·mL−1, a wide linear range of 4 × 10−5–4 ng·mL−1, and a satisfactory recovery of 93.3–99.6% in corn samples. With its diverse signal amplification capabilities, this aptasensor holds promise for detecting various analytes in environmental monitoring applications. • Ni 6 MnO 8 @C/AuNR improved the specific surface area, conductivity, and biocompatibility of the electrode. • MCA@Ce-MOF loaded massive signal molecules and biomolecules. • RecJ f -catalyzed target recycling further amplified the signals. • Achieved highly sensitive detection of ATZ with a detection limit of 4.9 fg·mL1. • This developed aptasensor was successfully applied to detect ATZ in the corn samples. [ABSTRACT FROM AUTHOR]