An investigation on the morphological and antimicrobial properties of electrospun silver nanoparticle- functionalized poly (vinyl chloride) nanofiber membranes.

Date

4-2010

Degree

Bachelor of Science in Applied Physics

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Emmanuel A Florido

Co-adviser

Rina B. Opulencia

Abstract

The morphology and antimicrobial properties of electrospun silver nanoparticle-functionalized nanofiber membranes from commercial Poly (vinyl chloride) (Ag-cPVC) were investigated. Ag-cPVC nanofiber membranes were successfully fabricated by electrospinning. Comparison between Fourier Transform Infrared (FTIR) spectra of cPVC with spectra of PVC in spectra library suggests that cPVC is chemically different from pure PVC. A cPVC solution was obtained by adding 9 g of cPVC to 100 ml of 50:50 Tetrahydrofuran-Dimethylformamide (TI IF-DMF). The cPVC solution was functionalized by adding 5 g of silver nitrate. Color change from blue to dark green after 48 hours of stirring proved reduction of silver ions (Ag+) to elemental Ag by action of DMF. Darkening from light to dark brown of Ag-cPVC fibers suggested subsequent reduction of remaining Ag+ on fibers after ultraviolet radiation. Energy dispersive X-ray spectroscopy confirmed the presence of Ag on irradiated and non-irradiated Ag-cPVC fibers. Atomic Force Microscope (AFM) phase image of Ag-cPVC fibers confirmed the presence of Ag nanoparticles on the fiber surface. Scanning Electron Microscope (SEM) images of cPVC fibers showed bead defects throughout the membrane. SEM and AFM topography images of Ag-cPVC fibers showed few defects and a rough, striated fiber surface. Calculated average fiber diameters are 237±79 nm for cPVC fibers, 341±124 nm for non-irradiated Ag-cPVC fibers, and 292±135 nm for irradiated Ag-cPVC fibers. The modal fiber diameter range is 200-300 nm. Antimicrobial assay results showed that Ag-cPVC fibers that were exposed to 192 Whrs of ultraviolet radiation have inhibited the growth of Escherichia coli and Bacillus subtilis while fibers with exposure to 23 Whrs of UV radiation showed no inhibition against E. coli, B. subtilis, Aspergillus niger and Candida krusei.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

Thesis

Document Type

Thesis

This document is currently not available here.

Share

COinS