Fabrication of Carboxymethyl Tamarind Kernel Gum‐Stabilized CuO Nanocomposite for Electrochemical Tetracycline Detection and Antibacterial Activity

ABSTRACT Nanocomposites of biopolymers and metal oxides have become an area of major interest in the field of environmental monitoring (antibiotics, dyes, and heavy metal detection) and biomedicine due to their specific physicochemical characteristics, which include antimicrobial activity, compatibility with biological entities, and drug‐carrying capacity, as well as their ability to augment imaging and therapeutic strategies. So, in this present study, a novel carboxymethyl tamarind kernel gum (CMTKG)‐stabilized copper oxide (CuO) nanocomposite was synthesized via an in situ approach. The synthesized CMTKG/CuO nanocomposite was thoroughly characterized by Fourier transform infrared spectroscopy (FTIR), x‐ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–vis), zeta potential, thermogravimetric analysis (TGA), field emission electron microscopy (FESEM), and energy‐dispersive x‐ray (EDX) analysis to elucidate its structural, morphological, and elemental characteristics. Furthermore, cyclic voltammetry (CV) was applied to assess the electrochemical performance of the CMTKG/CuO nanocomposite toward antibiotic drug detection, tetracycline hydrochloride (TC), while antibacterial assays were carried out to evaluate its inhibitory activity against Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ). The developed nanocomposite demonstrated a well‐defined linear response in the concentration range of 5.0 × 10 −5 – 5.0 × 10 −4 M ( R = 0.968), exhibiting a moderate sensitivity (0.697 µA µM −1 cm −2 ) along with a limit of detection (3.43 × 10 −5 M) for TC. The nanocomposite showed significant antibacterial activity with inhibition zone diameters of 13.3 and 15.3 for E. coli and S. aureus after 24 h of incubation. The CMTKG/CuO nanocomposite exhibits strong potential for biomedical and environmental applications through drug detection.