Formulation of an antibacterial dressing from green-synthesized silver nanoparticles using the leaf extract of Kalanchoe pinnata

AbstractGreen-synthesized nanoparticles are becoming popular due to their distinct biological applications and active phytoconstituents from plants. Kalanchoe pinnata is a traditional medicinal plant found in South America and has been used against bacteria, anti-inflammatory, and antiseptic substance by indigenous people. The study investigated the biosynthesis of silver nanoparticles (AgNP) from leaf extract, the formulation of nanomaterial-coated dressing, and the testing of its efficacy against multidrug-resistant bacteria. The maceration extraction method was employed for the methanolic crude extract, and preliminary phytochemical testing was performed using standard procedures. The aqueous extract of K. pinnata was used in the synthesis of silver nanoparticles and characterized by a UV-visible spectrophotometer and a Scanning Electron Microscope with Energy Dispersive X-ray spectroscopy. Agar-well diffusion technique was preferred to estimate the inhibition efficacy against bacteria; the cytotoxicity testing was assessed in the Vero cell lines, and then NPs were coated on the wound dressings. The preliminary phytochemical screening revealed the presence of terpenoids, phenols, amino acids, proteins, saponins, and carbohydrates. The UV-visible spectrophotometry peaked at 460 nm, and SEM analysis exhibited that the AgNPs were spherical in structure with an average measurement of 40 nm. At 200 µg//mL, the biosynthesized AgNP cytotoxicity test revealed a viability of 50%. The potency of antibacterial activity was obtained as Staphylococcus aureus > Pseudomonas aeruginosa > Escherichia coli based on the suppression rate. The synthesized nanoparticles-coated cotton dressings showed more effective antibacterial efficacy than uncoated dressings against multidrug-resistant bacteria. The study strongly reveals that the synthesized NP can be used as prospective therapeutic candidates, particularly against multidrug-resistant bacteria.