UPLC profiling of matcha extract capping biosynthesized copper oxide nanoparticles and their antimicrobial and cytotoxic potentials

Abstract

This research demonstrates a green synthesis and subsequent functionalization process of copper oxide nanoparticles (CuO NPs) utilizing matcha green tea extract as a sustainable reducing and functionalizing agent. UPLC-MS analysis revealed the presence of significant bioactive phytochemicals, notably epigallocatechin gallate (EGCG), which is implicated in the reduction process. Thorough characterisation (XRD, FT-IR, SEM) verified the synthesis of pure, crystalline, monoclinic CuO NPs with an average size of 16–24 nm. The nanoparticles had considerable antibacterial activity, exhibiting robust efficacy against Escherichia coli and Staphylococcus aureus, with a minimum inhibitory concentration of 250 µg/ml. CuO NPs-matcha exhibited significant, dose-dependent cytotoxicity against MCF-7 and Caco-2 carcinoma cells, with IC₅₀ values of 122.1 and 161.9 µg/ml, respectively. Crucially, they demonstrated markedly reduced toxicity towards non-cancerous Vero cells (IC₅₀ = 333.2 µg/ml), yielding selectivity indices of 2.73 and 2.06, which confirms a favorable selective profile. Although the positive control doxorubicin showed greater potency (lower IC₅₀), the CuO NPs-Matcha demonstrated significantly higher selectivity for cancer cells, suggesting a potentially improved safety profile despite its lower efficacy. These findings underscore the matcha-synthesized CuO NPs as a highly promising and biocompatible nanomaterial for specific medicinal applications, particularly in antibacterial and anticancer therapies.