BIOFILM FORMATION ON CARBON NANOTUBE/POLYCAPROLACTONE NANOCOMPOSITE COATED SURFACES

Embargo until
2015-05-01
Date
2014-05-09
Journal Title
Journal ISSN
Volume Title
Publisher
Johns Hopkins University
Abstract
Incorporating carbon nanotubes (CNTs) into polymer matrices to fabricate the CNT/polymer nanocomposites with enhanced mechanical, electrical and thermal properties has received a great deal of interest ever since the discovery of CNTs and their characteristics, such as high flexibility, low mass density and large aspect ratio. When disposed of at the end of consumer use, the fate of these nanocomposites will depend much on their interactions with the microorganisms. However, such microbial interactions with the CNT/polymer nanocomposites in the environment are not well understood. In this study, we investigated the biofilm formation, which involves the attachment and proliferation of microorganisms to a surface, on CNT/polycaprolactone (PCL) nanocomposite coated surfaces. For investigation of biofilm developing processes on both PCL and CNT/PCL nanocomposite coated surfaces and exploration of possible formation mechanisms, Pseudomonas.aeruginosa wild type was used as a model microorganism and biofilm growth in a drip flow reactor and static batch were performed. The results indicate that bacteria on the CNT/PCL nanocomposite surface started off alive at early time points and began to die afterwards. This was attributed to the digestion or biodegradation of the polymer layer that led to the exposure and accumulation of CNTs on the surface. Growth of living colonies was still able to occur despite the antimicrobial surface, with a dead layer of microorganisms close to CNTs exposed on the CNT/PCL nanocomposite surface and the living colonies on top of that. As the incubation time increased, the layer of dead cells increased in thickness and the presence of living colonies became more apparent.
Description
Keywords
Biofilm, Carbon Nanotube/Polymer Nanocomposite
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