Self‐Powered Potentiometric Sensing of Amoxicillin in Cow Milk and Waste Water Over Zinc Oxide Encapsulated Cellulose‐Grafted Polyaniline

A self‐powered potentiometric sensing of residual amoxicillin (AMX) in milk, meat extract and waste water of hospital has been demonstrated over zinc oxide, cellulose and polyaniline (ZnO‐en‐Cell‐g‐PANI) nanocomposite. The chemical structure, morphology, and properties of nanocomposite was investigated by suitable analytical techniques and ASTM methods. The observed analytical results confirms the porous and heterogeneous structure of composite with axial oriented crystallinity, ∼3.28 × 10 –4  S cm –1 electrical conductivity, and chemical responsive nature. Further, the 100 μm film of ZnO‐en‐Cell‐g‐PANI nanocomposite coated on ITO glass plate to use as an electrode for potentiometric sensing of residual AMX in waste water, meat extract and milk samples under optimum conditions and using own fabricated sensing set up. The experimental result revealed reproducibility, linear sensing range from 0.5 to 100.0 µM AMX concentrations, 2.24 mV µM −1  cm −2 sensitivity, 3.45 × 10 −2  µM detection limit, 180 s response time, 20 s recovery time, 45 days stability at 7.0 pH and room temperature. The mechanism for non‐enzymatic sensing of AMX has been proposed after correlating the induced potential and electrochemical surface interaction occurring between AMX molecules and ZnO‐en‐Cell‐g‐PANI.