Adhesion of Escherichia coli on to a series of poly(methacrylates) differing in charge and hydrophobicity

Abstract

The adhesion of three Escherichia coli strains on to six poly(methacrylates) differing in hydrophobicity and surface charge was measured as a function of time under laminar flow conditions. Polymers used were poly(methyl methacrylate) (PMMA), poly(hydroxyethyl methacrylate) (PHEMA) and copolymers of MMA or HEMA with either 15% methacrylic acid (MAA) or 15% trimethylaminoethyl methacrylate-HCl salt (TMAEMA-Cl). Bacterial and polymer surfaces were characterized by means of water contact angles and zeta potentials. Both the sessile drop contact angles and the zeta potentials of the bacterial surfaces were significantly different. No significant differences in the sessile drop contact angles of the polymer surfaces were observed. Using the Wilhelmy plate technique large contact angle hysteresis was observed for the different polymer surfaces. Surfaces of copolymers with MAA had more negative zeta potentials than those of the corresponding homopolymers. Surfaces of copolymers with TMAEMA-Cl had positive zeta potentials. The highest numbers of adherent bacteria were found on materials with positive zeta potentials, irrespective of the bacterial strain used. Bacterial adhesion on to copolymers with MAA was less than on to the corresponding homopolymers. Bacterial equilibrium adhesion values correlate with the zeta potentials of the polymer surfaces (r greater than 0.85). On substrates with less negative zeta potentials high numbers of adhered bacteria were observed. Additionally, the equilibrium bacterial adhesion values could be related with receding contact angles of polymer surfaces with negative zeta potentials (r greater than 0.86). High equilibrium adhesion values were obtained for polymers with high contact angles. No correlation between the zeta potentials and contact angles of the bacteria with the adhesion values was found.

Chlorhexidine delivery system from titanium/polybenzyl acrylate coating: Evaluation of cytotoxicity and early bacterial adhesion

“…51 Thus, according to some authors, a higher bacterial adhesion may be expected for the most hydrophobic PBA surface than for bare titanium. 52 However, our results showed lower adhesion when titanium was covered by the polymer. This supports the assumption that there is no simple relationship to correlate bacterial properties and surface energy of a substratum immersed in a protein-containing medium with bacterial adhesion.…”

Microbots Decorated with Silver Nanoparticles Kill Bacteria in Aqueous Media

“…52,53 Thus, these interactions promote, in this particular case, the adhesion to the Au cap where the AgNPs are attached (Figure 4 As the microbots contain Fe as a sandwitched material (Au/Fe/Mg) on the particle, AgNPs coated Janus microbots are capable to remove the bacteria from contaminated solutions using their magnetic properties. Figure 5A and Video S3 display a microbot externally guided using a simple permanent neodymium magnet.…”

<em>Vibrio fischeri</em> and <em>Escherichia coli</em> adhesion tendencies towards photolithographically modified nanosmooth poly (<em>tert</em>-butyl methacrylate) polymer surfaces

“…Marshall (1984) proposed that electrokinetic properties were a major factor in the attraction or repulsion of bacterial cells to surfaces. Several studies have indicated that bacterial adhesion negatively correlated with bacterial zeta potentials (van Loosdrecht et al 1989;Tsuneda et al 2003;Li and Logan 2004;Tsuneda et al 2004;Eboigbodin et al 2005), conversely, other studies have been reported that there are no relationship between the two parameters (Abbot et al 1983;Hogt et al 1985;Harkes et al 1991). A review by Donlan (2002) has discussed the contribution of bacterial fi mbriae in the surface attachment mechanism.…”