A Review on Green Synthesis of Copper Nanoparticles Using Plant Extracts: Methods, Characterization, and Applications.

Introduction: This review examines the green synthesis of copper nanoparticles (CuNPs) using plant extracts, highlighting eco-friendly, cost-effective, and biocompatible alternatives to traditional chemical and physical methods for sustainable nanotechnology applications.

Methods: Studies on green synthesis using plant extracts, comparative analyses with traditional methods, and applications of CuNPs in agriculture, medicine, and wastewater treatment were prioritized [1]. Characterization data, including UV-Vis, XRD, SEM, TEM, FTIR, and EDX, along with particle size and quantitative metrics (e.g., MICs, inhibition zones), were compiled [1].

Results: Green-synthesized CuNPs (1.8-37 nm) exhibit spherical morphology observed by SEM/TEM, surface functionalities identified by FTIR, and elemental composition determined by EDX [2]. Compared to traditional methods such as laser ablation (12 nm) and chemical reduction (10-30 nm), green synthesis reduces toxicity and energy consumption but faces scalability challenges [2]. CuNPs outperform AgNPs, AuNPs, and SeNPs, with MICs of 6.25-25 μg/mL and inhibition zones of 14-18 mm against Staphylococcus aureus and Escherichia coli [2]. In agriculture, CuNPs reduce the severity of Fusarium infection by 88% [2].

Discussion: Green CuNPs are effective germicides and catalysts due to the release of Cu²⁺ ions and generation of reactive oxygen species [3]. However, variable particle sizes and concentrationdependent toxicity, such as 100 mg/L in wheat, limit scalability and environmental safety [3].

Conclusion: Green synthesis offers a sustainable approach to producing CuNPs for applications in agriculture, medicine, and wastewater treatment [4]. Standardized protocols are needed to ensure reproducibility and scalability while minimizing environmental risks [4].