Keywords

Core-Shell nanoparticle, Copper loaded silica, Antibacterial, Sol-Gel, Copper Biocide.

Abstract

A novel core-shell silica based antimicrobial nanoparticle was synthesized. The Stöber silica shell has been engineered to accommodate copper. Synthesis of the core-shell Cu-silica nanoparticle (C-S CuSiNP) involves preparation of base-hydrolyzed Stöber silica “seed” particles first, followed by the acid-catalyzed seeded growth of the Cu-silica shell layer around the core. Scanning electron microscopy and transmission electron microscopy showed monodispersed, spherical shaped nanoparticles with smooth surface morphology. Characterization of particle size distribution in solution by the Dynamic Light Scattering (DLS) technique was fairly consistent with the electron microscopy results. Loading of Cu to nanoparticles was confirmed by the SEM-Energy Dispersive X-Ray Spectroscopy (EDS) and Atomic Absorption Spectroscopy (AAS). Antibacterial efficacy of C-S CuSiNP was evaluated against E.coli and B.subtilis using Cu hydroxide (“Insoluble” Cu compound) and copper sulfate as positive control and silica “seed” particles (without Cu loading) as negative control. Minimum Inhibitory Concentration (MIC) of C-S CuSiNP was evaluated by measuring the fluorescent intensity of resorufin to determine the decrease in viable cells with increase in copper concentration in C-S CuSiNP. The MIC value of C-S CuSiNP against both E.coli and B.subtilis was estimated to be 4.9 ppm. Bac-light fluorescence microscopy based assay was used to count relative population of the live and dead bacteria cells. Antibacterial study clearly shows that C-S CuSiNP is more effective than insoluble Cu hydroxide particles and copper sulfate at equivalent metallic Cu concentration, suggesting more soluble Cu in C-S CuSiNP material due to its coreshell design.

Notes

If this is your thesis or dissertation, and want to learn how to access it or for more information about readership statistics, contact us at STARS@ucf.edu

Graduation Date

2011

Semester

Fall

Advisor

Santra, Swadeshmukul

Degree

Master of Science (M.S.)

College

College of Medicine

Department

Molecular Biology and Microbiology

Degree Program

Molecular and Microbiology

Format

application/pdf

Identifier

CFE0004479

URL

http://purl.fcla.edu/fcla/etd/CFE0004479

Language

English

Release Date

June 2015

Length of Campus-only Access

3 years

Access Status

Masters Thesis (Open Access)

Subjects

Dissertations, Academic -- Sciences, Science -- Dissertations, Academic

Download

Share

COinS