Giant Milkweed Plant-Based Copper Oxide Nanoparticles for Wound Dressing Application: Physicochemical, Bactericidal and Cytocompatibility Profiles

Present wound dressing materials have limitation in treating skin pathogens colonization associated with open wound infections. Recently, plant-based synthesis of inorganic oxide nanomaterials has received countless attention to tackle the mention limitation. This study investigated the physicochemical, bactericidal and cytocompatibility properties of copper oxide (CuO) nanoparticles from giant milkweed medicinal plant were produced at different calcination temperatures (i.e., 400 and 500 °C). Giant milkweed plant is scientifically known as Calotropis gigantea (C. gigantea). The oval-shaped CuO-500C exhibited improved bactericidal properties toward tested skin pathogens than CuO-400C. Successful green synthesis of CuO nanoparticles with the presence of bioderived elements was affirmed through both EDAX and XRD. Furthermore, FTIR and UV–visible analyses confirmed phenolic and carbonyl compounds. The MIC value for CuO-400C and CuO-500C toward the skin pathogens was ranging from 1.25 to 10 mg/mL and 0.3125 to 5 mg/mL, respectively. MBC value for CuO-400C and CuO-500C was 20 mg/mL and 2.5–20 mg/mL, respectively. From time-kill assay we found that Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) colonies began to decrease substantially after 6 h, and bactericidal activity was noticed at 12 h. However, the methicillin-resistant Staphylococcus aureus (MRSA) treated with CuO-500C was fully inhibited at 24 h. Besides, zone of inhibition of 10 mg/mL CuO-500C was greater than other samples. CuO-500C (2.5–10 mg/mL) had good cytocompatibility (> 90