(577b) Fabrication and Characterization of Polymeric Surfaces for Bacteria Adhesion in Whole Cell Biosensor Using PECVD

In 2003, a $7.3 billion world market was covered by biosensors, which is expected to grow to $10.8 billion by year 2007. The goal was to develop a biosensor using Pseudomonas Putida (Strain TVA8) bioluminescence bacteria to detect the presence of trichloroethylene¹. Bacteria are fairly mobile it was necessary to immobilize them in such a way that they remain attached to the desired substrate. Bacterial adhesion depends on many factors like surface chemistry, hydrophobicity, and surface roughness. To immobilize the bacteria on the substrate, the surface of the substrate was modified with a hydrophobic polymer. In this investigation, Plasma Enhanced Chemical Vapor Deposition (PECVD) was used to fabricate non-biodegradable, hydrophobic fluorocarbon films. To change the surface roughness and hydrophobicity the films were deposited at different pulse conditions (i.e., 10/100, 10/200 and continuous pulse) using methacrylate fluorocarbon precursors with different distinct fluorocarbon group, such as trifluoroethyl, pentafluoropropyl and heptafluorobutyl. The deposited film showed evidence of retention of the desired fluorine functional groups as observed in the FTIR spectrum. AFM and contact angle measurement techniques were used to determine the surface roughness and hydrophobicity of the surface. Finally bacterial adhesion experiments were carried out on the modified hydrophobic surfaces and results demonstrated that bacteria attached effectively to hydrophobic surface in contrast to unmodified surface.

1.Applegate B, Kehrmeyer S R, Sayler G. 1998. A chromosomally based tod-luxCDABE whole-cell reporter for benzene, toluene, ethybenzene, and Xyene (BTEX) sensing. Applied and Environmental Microbiology 64(7) 2730-2735