Biofabrication of size controllable silver nanoparticles - A green approach

A facile biosynthetic approach for the size controllable production of silver nanoparticles (AgNPs) using the leaf extract of Cinnamomum tsoi as reducing and capping agent is developed. The polyphenolic functionalities present in the extract are essentially responsible for the synthesis and stabilization of AgNPs. The size and morphology of the AgNPs were effectively tuned by changing the volume of the extract. The availability of oxidized polyphenols play key role in tuning the size and morphology of the prepared NPs. The as prepared AgNPs were characterized by X-ray diffraction (XRD), Ultraviolet-visible spectroscopy (UV-visible), Transmission electron microscopy (TEM), Selected area electron diffraction (SAED), Dynamic light scattering (DLS) and Fourier transform infrared (FTIR) techniques. FTIR and Zeta potential measurements have confirmed the decoration of oxidized polyphenols on the surface of synthesized AgNPs. TEM and DLS measurements revealed the size variation of AgNPs with change in the volume of plant extract. The prepared AgNPs showed the significant inhibition of alpha-amylase and alpha-glucosidase enzymes and exhibited a dose dependent activity. The enhanced in-vitro antidiabetic activity of the AgNPs may be due to the oxidized polyphenols present on the AgNPs surface which was confirmed by FTIR analysis. In addition, the present method is substitute to the chemical approaches of size controlled AgNPs synthesis that are being used nowadays. (C) 2017 Elsevier B.V. All rights reserved.