Green Synthesis of AgNPs Coated Mesoporous Silica Nanoparticles Using Tyrosine as Reducing/Stabilising Agent

Abstract

A novel, simple and environmental friendly approach to fabricate silver nanoparticles (AgNPs) on mesoporous silica nanoparticles (MSNs) using tyrosine (Tyr) as biological reducing agent was developed. The functionalization of Tyr with MSNs (Tyr-MSNs) (150 nm in length) by the sol-gel process was confirmed by the characteristic peaks of amino, carboxyl and silanol groups appeared in FTIR spectrum and the change of the zeta potential from 0 mV at pH 2 to-60 mV at pH 12. Then, AgNPs were formed on the surface of Tyr-MSNs (Tyr-MSN@AgNPs) via only reducibility from phenolic group of Tyr and catalytic activity from base at room temperature. TEM images and UV-Visible absorption band at 420 nm supported the obtained AgNPs (18 nm at pH 11) were tightly bound to Tyr-MSNs even after centrifugation at high speed. These Tyr-MSN@AgNPs would be potentially used as drug carrier in biomedical applications.