Vasanthakumar, AarthiAarthiVasanthakumarPriyadharshini, S.S.PriyadharshiniVenkatesan, Kamalesh BalakumarKamalesh BalakumarVenkatesanAyyanar, M.M.AyyanarThirumurugan, ArunArunThirumuruganChidhambaram, N.N.Chidhambaram2026-07-072026-07-072026-07NEXT MATERIALS, 12, 102365 (2026). https://doi.org/10.1016/j.nxmate.2026.1023652949-8228https://hdl.handle.net/20.500.12740/24779Green synthesis offers an environmentally benign and sustainable approach for preparing metal nanoparticles (NPs) for biomedical and agricultural applications. In this study, we report the preparation of copper (Cu), zinc (Zn), and bimetallic copper/zinc (Cu/Zn) nanoparticles using Melia dubia Cav. (Malabar neem) leaf extract and their biological applications. Analytical characterizations of the as-synthesized nanoparticles were performed using X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, UV-visible diffuse reflectance spectroscopy (UV-vis DRS), and scanning electron microscopy (SEM). The mean crystallite sizes of the Cu, Zn, and Cu/Zn nanoparticles were approximately 25, 12, and 16 nm, respectively. The FTIR spectra confirmed the involvement of hydroxyl, amide, and aromatic functional groups in the reduction and capping procedures of nanoparticle generation. The Cu/Zn bimetallic nanoparticles exhibited distinctive optical characteristics, indicating alloy formation and synergistic effects. Among the synthesized samples, the Cu/Zn nanoparticles exhibited superior antibacterial performance, achieving maximum zones of inhibition (ZOI) of 24 mm against E. coli and 22 mm against P. aeruginosa at 100 & micro;g/mL concentration. Similarly, the Cu/Zn nanoparticles exhibited the strongest antioxidant efficacy, with maximum DPPH and ABTS radical scavenging activities of 85% and 79% at 400 & micro;g/mL, respectively. The bimetallic system demonstrated potent anticancer performance, with an IC50 value of 33.38 & micro;"g/mL against HCT116 human colon cancer cells. Furthermore, in agricultural assays, the Cu/Zn nanoparticles significantly enhanced seed germination and radicle elongation, reaching a maximum length of 4.8 cm in Vigna radiata (green gram) and 1.9 cm in Trigonella foenum-graecum (fenugreek) compared with the control and monometallic treatments. Overall, the biocompatible Cu/Zn nanoparticles derived from Melia dubia leaf extract show excellent potential for biomedical and agricultural applications."info:eu-repo/semantics/openAccessMelia dubiaCu/Zn nanoparticlesAntibacterialAntioxidantAnticancerArticulohttps://doi.org/10.1016/j.nxmate.2026.102365