Biosynthesis of copper oxide nanoparticles with and without capping agents v1

This protocol describes the synthesis of copper oxide nanoparticles using a Caesalpinia sappan extract as a reducing agent with and without different capping agents. Copper oxide nanoparticles were prepared by reducing copper sulfate dissolved in water with the aqueousextract of C. sappan according to our previously described method (Sasarom et al, 2023).