A Novel Approach: Synthesis of Biologically Potent Copper Oxide Nanoparticles Derived From Expired Medicine

ABSTRACT The present work introduces a sustainable and economical approach for recycling pharmaceutical waste, specifically expired paracetamol and Disprin, into biologically active copper oxide nanoparticles (CuONPs). The synthesized nanomaterials were examined using FT‐IR, XRD, SEM, TEM, and EDS techniques. FT‐IR spectra confirmed the presence of Cu–O vibrations at 520 and 540 cm − 1 , while XRD analysis revealed a monoclinic crystalline phase with high structural stability. EDS analysis verified elemental purity, showing prominent Cu peaks and weight percentages of 73.42% for P‐CuONPs and 76.59% for D‐CuONPs. DLS measurements indicated moderately polydisperse behavior with Z‐average hydrodynamic diameters ranging from 1589.1 to 3786 nm, while negative zeta potential values (−13.3 to −21.2 mV) suggested moderate colloidal stability. Morphological investigations by SEM and TEM showed spherical, uniformly distributed particles with an average size of 20–50 nm. Theoretical calculations and molecular dynamics simulations supported the experimental findings. P‐CuONPs effectively inhibited S. aureus 17(±0.3) mm and E. coli 20(±0.4) mm, whereas D‐CuONPs showed activity only against E. coli 15(±0.3) mm. Neither type exhibited antifungal effects against C. albicans . Antioxidant assays confirmed strong free radical scavenging properties, with P‐CuONPs performing most efficiently with an IC 50 value of 45.58 µg/mL. Anti‐inflammatory analysis revealed concentration‐dependent inhibition, comparable to sodium diclofenac, with P‐CuONPs showing superior activity compared to D‐CuONPs. Overall, this study highlights an eco‐friendly strategy for repurposing expired drugs into CuONPs with significant antimicrobial, antioxidant, and anti‐inflammatory potential, offering promising applications in biomedical research.