Novel Copper (Cu) Loaded Core–Shell Silica Nanoparticles with Improved Cu Bioavailability: Synthesis, Characterization and Study of Antibacterial Properties

Authors: Maniprasad, Pavithra; Santra, Swadeshmukul

Source: Journal of Biomedical Nanotechnology, Volume 8, Number 4, August 2012 , pp. 558-566(9)

Publisher: American Scientific Publishers

Buy & download fulltext article:

OR

Price: $113.00 plus tax (Refund Policy)

Abstract:

We report synthesis of a novel core–shell silica based antimicrobial nanoparticles where the silica shell has been engineered to accommodate copper (Cu). Synthesis of the core–shell Cu-silica nanoparticle (C–S CuSiO2NP) 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. The Scanning Electron Microscopy (SEM) and the Transmission Electron Microscopy (TEM) measured the seed particle size to be ∼380 nm and the shell thickness to be ∼35 nm. The SEM particle characterization confirms formation of highly monodispersed particles with smooth surface morphology. Characterization of particle size distribution in solution by 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). The Cu loading was estimated to be 0.098 μg of metallic copper per mg of C–S CuSiO2 NP material by the AAS technique. Antibacterial efficacy of C–S CuSiO2 NP was evaluated against E. coli and B. subtilis using Cu hydroxide ("Insoluble" Cu compound, sub-micron size particles) as positive control and silica "seed" particles (without Cu loading) as negative control. Bacterial growth in solution was measured against different concentrations of C–S CuSiO2 NP to determine the Minimum Inhibitory Concentration (MIC) value. The estimated MIC values were 2.4 μg metallic Cu/mL for both E. coli and B. subtilis. 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 CuSiO2 NP is more effective than insoluble Cu hydroxide particles at equivalent metallic Cu concentration, suggesting improvement of Cu bioavailability (i.e., more soluble Cu) in C–SCuSiO2 NP material due to its core–shell design.

Keywords: ANTIBACTERIAL; COPPER BIOCIDE; COPPER LOADED SILICA; CORE-SHELL NANOPARTICLE; SOL-GEL

Document Type: Research Article

DOI: http://dx.doi.org/10.1166/jbn.2012.1423

Publication date: August 1, 2012

More about this publication?
  • Journal of Biomedical Nanotechnology (JBN) is a peer-reviewed multidisciplinary journal providing broad coverage in all research areas focused on the applications of nanotechnology in medicine, drug delivery systems, infectious disease, biomedical sciences, biotechnology, and all other related fields of life sciences.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Terms & Conditions
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Tools

Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content

Text size:

A | A | A | A
Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages. print icon Print this page