Green-synthesized copper oxide microsponge gel loaded with Ixora coccinea and Rhododendron arboreum for antibacterial wound healing applications

Abstract

Background

Copper oxide microsponges (CuOMs) synthesized using Ixora coccinea L. and Rhododendron arboreum Sm. flower extracts have shown potential as novel antimicrobial agents. This study aims to evaluate the antibacterial efficacy of these green-synthesized CuOMs and their application in wound care.

Methods

CuOMs were fabricated via a quasi-emulsion solvent diffusion method using copper nitrate, with plant extracts serving as reducing and stabilizing agents. The synthesized microsponges were characterized using UV, FTIR, XRD, SEM-EDX, Zeta sizer and LC-MS. The antibacterial activity was assessed using agar well diffusion, time-kill assays and biochemical analyses including protein and cytoplasmic leakage against wound-associated pathogens such as Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Enterococcus faecalis.

Results

The CuOMs incorporated gel exhibited substantial antibacterial activity, with inhibition zones ranging from 14 to 22 mm. LC-MS studies shows presence of quercetin and rutin in both plant extract plays a major role in wound healing. Time-kill assays demonstrated rapid bactericidal effects within 2 h, particularly against P. aeruginosa. Protein and cytoplasmic leakage assays indicate significant disruption of bacterial membranes, confirming the microsponge mechanism of action. Among all the tested pathogens, P. aeruginosa showed the greatest susceptibility.

Conclusion

The biosynthesized CuOMs exhibited strong antibacterial properties and effectively disrupted bacterial cell integrity. The incorporation of these compounds into a topical gel matrix offers a promising strategy for wound healing and infection control. The synergistic effect of copper oxide and bioactive plant compounds supports their potential as safe and effective alternatives for antimicrobial wound therapy.