Chemically functionalized CuO/Sodium alginate grafted polyaniline for nonenzymatic potentiometric detection of chlorpyrifos.

Non-enzymatic sensing of chlorpyrifos (CPF) has been demonstrated over structurally functionalized the ternary bio nanocomposite comprised of cupric oxide, sodium alginate, and polyaniline-based hybrid (CuO/SA-g-PANI) based electrode using a laboratory designed portable potentiometric set up. The prepared composite and constituents were characterized for structure, morphology, and physical properties with the help of fourier transform infrared, X-ray diffraction, Scanning electron microscope, and other relevant standard methods. The obtained results revealed the formation of porous, electrical conductivity, structurally functionalized, responsiveness composite due to molecular engineering, and structural synergism for sensing applications. Further, the film of the prepared composite was explored as the electrode for nonenzymatic potentiometric sensing of residual chlorpyrifos in synthetic and natural sample i.e., tap water, soil, mango, and cabbage. The sensor exhibits a wider sensing range 1.0-120.0 μM, improved sensitivity 1.8790 mV·μM-1·cm-2, detection limit 0.375 μM, response time 120 s, recovery time 16 s with 99.80 % accuracy, and stability of 72 days at neutral 7.0 pH and ambient temperature i.e. 25 °C. Further, the sensing mechanism has been also explained on the basis of structural change in CPF and electrode materials due to their surface interaction along with formation induced electrode potential.