Fabrication, characterization and application of nanofibers coated with nanoparticles

Abstract

The fabrication of polymer nanofibers using electrospinning have become a widely studied field in nanotechnology due to its potential applications in many areas like tissue engineering, catalysis and as a template for synthesis of interesting nanostructures. This thesis is aimed towards the fabrication and characterization of nanofibers and nanoparticles from water soluble biocompatible polymers, hydroxyl ethylcellulose (HEC) and poly (vinyl alcohol) (PVA) for fundamental studies and potential applications. A uniform chain-like assembly of silver nanoparticles was obtained by electrospinning HEC/PVA polymers in the presence of AgNO3. It was found that the reduction of AgNO3 occurred in a few minutes in the presence of HEC. The PVA/AgNP nanofibers were used as catalyst in transfer hydrogenolysis reaction while the HEC/PVA/AgNP nanofibers were used in antimicrobial studies. The preliminary results are encouraging. The HEC/PVA nanofibers without AgNP were electrospun, characterized and used in extraction of environmental samples. The same nanofibers were also used as scaffolds in cell growth studies. The adhesion and development of human glioma cells (U 251) on the HEC/PVA nanofibers were studied. The electrospun nanofibers were used as sacrificial templates to produce free-standing highly porous gold nanofibers. Gold and silver nanoparticles were synthesized from HAuCl4 and AgNO3 using HEC which acted as both reducing as well as stabilizing agent. The gold nanoparticles showed snake shaped morphology while the silver nanoparticles showed floret morphology.