Ciprofloxacin-loaded copper oxide nanoparticles: Cutting-edge multifunctional nano-therapeutics with superior antidiabetic, antioxidant, anti-inflammatory, and antibacterial potency against drug-resistant pathogens

Abstract

This study presents a green, cost-effective synthesis of ciprofloxacin-loaded copper oxide nanoparticles (CIP@Cu₂O NPs), highlighting their potential as multifunctional therapeutics with superior antidiabetic, antioxidant, anti-inflammatory, and antibacterial activities, particularly against drug-resistant pathogens. Cu₂O nanoparticles were synthesized using ascorbic acid as a reducing agent, then functionalized with ciprofloxacin, resulting in CIP@Cu₂O NPs with improved biomedical properties. Comprehensive characterization through FT-IR, UV–Visible spectroscopy, X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) verified the homogeneity, morphology, and crystalline structure of the nanoparticles, with SEM analysis revealing spherical to oval shapes and particle size enhancement from 26 nm for Cu₂O NPs to 38 nm upon ciprofloxacin loading. The optical properties, assessed through UV–Visible spectroscopy, showed direct and indirect bandgap energies ranging from 1.85 to 3.14 eV and 1.47 to 2.72 eV, respectively, while XRD confirmed the cubic crystal structure corresponding to the Cuprite phase. The multifunctionality of CIP@Cu₂O NPs was demonstrated through multiple assays: antioxidant activity with 44.89 % 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition at 700 µg/mL, strong anti-inflammatory response with up to 68 % inhibition at 800 µg/mL, and notable antidiabetic activity, achieving 97.95 % α-amylase and 85.74 % α-glucosidase inhibition at 80 µg/mL. Furthermore, antibacterial studies revealed enhanced efficacy against multiple bacterial strains, showing inhibition zones larger than those of Cu₂O NPs or ciprofloxacin alone. This synergy between ciprofloxacin and copper oxide underscores the potential of CIP@Cu₂O NPs as advanced nanotherapeutic agents for drug delivery, antimicrobial treatments, and management of oxidative stress-related diseases. The findings open pathways for the development of versatile, sustainable nanoparticles for complex therapeutic needs.