RADU LUCIAN OLTEANU, CRISTINA MIHAELA NICOLESCU, MARIUS BUMBAC, IOANA DANIELA DULAMA, RODICA MARIANA ION, IOANA RALUCA SUICA BUNGHEZ STUDY ON CRITICAL MICELLE CONCENTRATION INFLUENCE IN GREEN SYNTHESIS OF SILVER NANOPARTICLES ASSISTED BY SAPINDUS MUKOROSSI AQUEOUS EXTRACT Silver nanoparticles synthesis mediated by plant extracts involves the colloidal stability of generated metallic particles in solutions. Formation of micelles in solutions influences the nanoparticle synthesis process and consequently, the surface plasmonic response (SPR) of the formed silver nanoparticles. Critical micelle concentration (CMC) of Sapindus mukorossi aqueous extract has been determined with ultraviolet-visible spectroscopy, two methods were used: dye micellization method, and correlation of silver nanoparticles SPR with the variation of surfactant concentration. Results obtained for CMC determination by the two methods were highly reproducible and in good correlation indicating that micelles formed by saponins present in the Sapindus mukorossi aqueous extract are useful as effective structure-driving agents to synthesize colloidal metallic nanoparticles, offering them proper growth conditions. Silver nanoparticles synthesis mixtures were studied, with Sapindus mukorossi aqueous extract and silver nitrates as precursors, in acidic and basic media, at room temperature to establish correlations between saponins structure modifications and surface plasmonic response of metallic nanoparticles. Light absorption spectrometric techniques (ultraviolet-visible and infrared), X-ray diffraction and scanning electron microscopy were used to characterize the synthesis process.
Keywords: critical micelle concentration, Sapindus mukorossi, silver nanoparticles green synthesis