A new sensor for bacteria using binding or specific degradation of stimuli responsive polymers

Lead Research Organisation: University of Sheffield
Department Name: Chemistry


The project will investigate the use of a smart polymer for the detection of bacteria. The underlying principle of this work is that the binding of the chain ends of the hyperbranched polymers can be used to attach the polymer to the cell surface of bacteria. In some cases this binding can progress the polymer through a critical conformational change, in which the polymer changes, in aqueous soloution, from an open solvated coil to a tight non-solvated globule. In other instances the conformational change can be brought about after binding by a small temperature change. Furthermore, careful design of the chain-end ligand can be used to ensure that binding can be formulated to be specific to individual sites on different species of bacteria,. The change from open coil to tight globule can be detected by monitoring fluoresence from chemical labels situated on the polymer chain . These labels report on the chain's conformation by a change in fluoresence. The project will investigate the use of both soluble polymers, which could be added to a wound bed as a method of detecting the presence of bacteria and also immobilized hydrogel materials. The latter might be used as active wound dressings. In another version of this technology hyperbranched polymers will be synthesized to have peptide chain ends that can be degraded by specific extracelluar proteases. In this instance, the polymers will detect the bacteria following degradation of the end groups, which will expose polar carboxylic end groups. Thus, these systems will progress from a tight non-solvated globule to an open solvated chain in the presence of the target bacteria. In brief, we propose to develop novel polymer technology to rapidly detect bacteria with an easily observed optical signal.
Description We discovered that certain polymers can respond to the presence of bacteria by binding to cell surface features. The work was the first to show that polymers, in a similar manner to proteins, can change conformation on binding. In this case it is the end groups of the polymers that bind.
Exploitation Route The results are of great importance toothless speaking to develop systems for detecting pathogens. Already we are working with medical devices companies and clinicians to develop cost effective and rapid,point of care detection systems.
Sectors Healthcare

Description The work is being progressed in a TSB project with Smith and nephew aimed at wound dressings and a Wellcome trust funded project aimed at contact lenses for detecting infection. Wound dressing prototypes are under construction.
First Year Of Impact 2013
Sector Healthcare
Impact Types Economic

Description Collaborative research
Amount £800,000 (GBP)
Funding ID TSB 101224 
Organisation Innovate UK 
Sector Public
Country United Kingdom
Start 06/2013 
End 06/2015
Description UK-India Centre for Advanced Technology for Minimising the indiscriminate use of antibiotics
Amount £1,500,000 (GBP)
Funding ID MR/N501888/2 
Organisation Medical Research Council (MRC) 
Sector Academic/University
Country United Kingdom
Start 05/2015 
End 12/2018
Description Wellcome Affordable Healthcare in India
Amount £888,000 (GBP)
Funding ID 0998800/B/12/Z 
Organisation Wellcome Trust 
Department Wellcome Trust Bloomsbury Centre
Sector Academic/University
Country United Kingdom
Start 06/2013 
End 12/2017