Water droplets on the Droplet Microarray (Acknowledgement to Aquarray)
An article has just been published in Biointerphases to contextualize our recent polymer library observations in the wider literature of water contact angle (WCA) and surface energetics, and this is now available online.
Often the view is expressed that WCA or other wettability/surface energy measurements made on a material surface can be used to predict cellular attachment to materials, e.g., bacteria attach to hydrophobic surfaces. In the article, the authors present a perspective emerging from their work that has failed to find relationships between WCA and microbial and stem cell attachment within large diverse material libraries and compare with the literature concluding that such simple rules are (unfortunately) wholly inadequate to explain cell–material interactions.
Wettability or the WCA are indicated as poor predictors of mammalian and microbial cellular responses when dealing with diverse libraries of material surface chemistry. There are a series of relatively hydrophobic polymers that resist bacterial attachment and biofilm formation to a range of pathogens. The mechanism by which these act, remains to be elucidated, but is distinct from that involving interfacial water association at the surface, for ethylene glycols. Molecular descriptors have been found to correlate with bacterial attachment but as yet without the proposition of a causative mechanism. Bacterial surface sensing is anticipated to play a significant role. Throughout the literature in vitro culture conditions differ and can be critical in disrupting the adhesion of bacterial cells to material surfaces.
The authors are jointly funded both by the Wellcome Trust Senior Investigator scheme and an EPSRC Programme grant.
Posted on Thursday 13th July 2017