Optimization of nanosilver purification process with Camellia sinensis L. extract as bioreductor

Nanosilver can be described as a nanoparticle synthesized from silver metal with a size range of 1–100 nm. Nanosilver synthesis can be performed using green tea leaf extract (Camellia sinensis L.) as a bioreductor due to its flavonoid content. The content of flavonoid compounds is able to reduce silver metal ions (Ag+) derived from AgNO3 as metal precursors so that silver nanoparticles can be produced. This study aimed to obtain the optimum time and speed of centrifugation in nanosilver purification with green tea leaf bioreductors using the Central Composite Design (CCD) method. This study used two independent variables namely the duration and speed of centrifugation. The effect of centrifugation duration and speed on wavelength, transmittance percentage, and particle size of purified were analyzed by response surface methodology using the R software. The duration and speed of the optimum formula for the nanosilver purification process were obtained using the CCD method. The optimum conditions obtained were the centrifugation duration of 22 minutes and the centrifugation speed of 3500 rpm. Furthermore, the content of tannin compounds in green tea leaves was determined using thin layer chromatography.