Antibacterial activity of Ag-Au alloy NPs and chemical sensor property of Au NPs synthesized by dextran

作者：Bankura Kalipada; Maity Dipanwita; Mollick Md Masud Rahaman; Mondal Dibyendu; Bhowmick Biplab; Roy Indranil; Midya Tarapada; Sarkar Joy; Rana Dipak; Acharya Krishnendu; Chattopadhyay Dipankar^*

来源：Carbohydrate Polymers, 2014, 107: 151-157.

DOI：10.1016/j.carbpol.2014.02.047

• Nanoparticles
• Ag-Au alloy
• Dextran stabilized nanoparticles
• Antimicrobial activity
• Colorimetric sensor

Gold and silver-gold alloy nanoparticles with mean diameter of 10 nm and narrow size distribution were prepared by reduction of the correspondent metal precursors using aqueous dextran solution which acts as both a reducing and capping agent. The formation of nanoparticles was characterized by UV-vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and dynamic light scattering (DLS). The silver and gold nanoparticles exhibited absorption maxima at 425 and 551 nm respectively; while for the bimetallic Ag-Au alloy appeared 520 nm in between them. TEM images showed monodispersed particles in the range of 8-10 nm. The crystallinity of the nanoparticles was assured by XRD analysis. DLS data gave particle size distribution. The dextran stabilized Au nanoparticles used as a colorimetric sensor for detection and estimation of pesticide present in water. The dextran stabilized Ag-Au alloy nanoparticles exhibited interesting antimicrobial activity against bacteria at micromolar concentrations.

• 出版日期2014-7-17