A biofilm is a cluster of bacteria, attached to each other and embedded in a matrix of polymeric substances, so called slime. Within this biofilm, bacteria are more resistant to antimicrobials and host defenses than in an individual state. To avoid the formation of biofilms, e.g. in clinical use of medical devices, it is beneficial to use materials that prevent any bacterial attachment from the start. Polymers of tert-butyl cyclohexyl acrylate (t-BCHA) repel bacteria. However, which of the three moieties in this polymer (tert-butyl, cyclohexyl, ester) contributes the most to the biofilm resistance is unknown.
Andrew L. Hook, University of Nottingham, UK, and colleagues co-polymerized t-BCHA with structural homologues featuring cyclic, aromatic, and linear hydrocarbon substituents. The monomers were mixed in various ratios resulting in different polymers with a statistic monomer sequence, hence, each presented different moieties on the surface. The polymers were tested for bacterial attachment and subsequently the surface moiety was determined by mass spectrometry (ToF-SIMS).
The team found that chemical groups in fact could be ranked for their ability to prevent bacterial attachment. A rigid and nonpolar moiety on the surface prevents attachment of bacteria best.
- Bacterial Attachment to Polymeric Materials Correlates with Molecular Flexibility and Hydrophilicity,
Olutoba Sanni, Chien-Yi Chang, Daniel G. Anderson, Robert Langer, Martyn C. Davies, Philip M. Williams, Paul Williams, Morgan R. Alexander, Andrew L. Hook,
Adv. Healthcare Mat. 2014.