Gold Nanoparticles Biosynthesis Through Green Synthesis Mediated by Leaf Extract from Diospyros Kaki L. (Persimmon) Using the Microwave Extraction Method

The objective of this study was to prepare metallic gold nanoparticles (AuNPs) from the Diospyros kaki L. (persimmon) leaf (DKL) extract, which was grown in the Trabzon province of Türkiye, using microwave extraction. Separate additions of 0.1 and 0.5 mL DKL extract were made to the 0.5 mM HAuCl₄.3H₂O solution while the heater was kept at 25 °C and stirring continuously. In this method, UV-Vis spectroscopy (300–800 nm) absorption measurements were performed on extracts of Diospyros kaki L. leaves at different time intervals (10, 20, 30, 60, 120, and 1440 min). Green chemistry principles were utilized in the preparation of gold nanoparticles (AuNPs), which were characterized by UV–visible, X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and Zetasizer. FTIR analysis can be used to determine the various functional groups that were synthesized in the gold (Au) nanoparticles. Based on the AuNPs’ XRD peaks, the average crystallite size was determined to be 25.99 nm. Zetasizer study results showed that the average particle size of Au nanoparticles produced by microwave extraction in an aqueous medium was 45.44 ± 1.095 nm, the zeta potential (ZP) was − 16.9 mV ± 1.19, and the polydispersity index was 0.316 ± 0.009. The UV-Vis absorption spectra of the AuNP solutions were stable for approximately 2.5 to 3 months when they were kept in a refrigerator.