Biofilm Activity Analyser for Healthcare Applications

Lead Research Organisation: University of Warwick
Department Name: Chemistry

Abstract

In this feasibility study, work will be carried out by Warwick in order to develop a biocompatible diamond based biofilm activity analyser, which is capable of placement within the small, non-disposable plastic tubing associated with the waterlines of dental unit water systems (DUWS's) and internal tubing of dialysis machines. Biofilm build-up is a huge problem as if left unchecked can led to potential life-threatening bacterial infections in the patient, particularly problematic with those already suffering from illness. The sensor will be designed to monitor biofilm growth continuously, based on electrochemical principles. The initial part of the research undertaken at Warwick will be to design an appropriate sensor geometry which is both small enough to fit into the associated tubing but also has the sensitivity to detect and monitor biofilm build-up on the sensor surface. Additional capabilities, such as the ability of the sensor to clean itself, will also be built in. Using personnel at Warwick, skilled in the art of processing diamond materials, inverse electrode structures will be laser machined into sheets of insulating diamond. The diamond will then be sent for conducting diamond overgrowth, and then be returned to Warwick for highly specialised polishing to produce co-planar insulating-conducting diamond structures (the sensor). The sensor will then be electrically contacted and test rigs at Warwick built which replicate the water /dialysate environments of DUWS's and dialysis units. The sensor(s) performance (in terms of an output current) will be monitored continuously and the sensor periodically assessed to ascertain the extent of biofilm build-up on the surface. Simultaneous measurements of microbial content in the water will also be taken. This is in order to relate extent of biofilm build up to numbers of colony forming units, such that it is possible to programme the sensor to notify the user when biofilm activity has risen above a "safe" level.

Technical Summary

In this feasibility study, work will be carried out by Warwick in order to develop a biocompatible diamond based biofilm activity analyser, which is capable of placement within the small, non-disposable plastic tubing associated with the waterlines of dental unit water systems (DUWS's) and internal tubing of dialysis machines. Biofilm build-up is a huge problem as if left unchecked can led to potential life-threatening bacterial infections in the patient, particularly problematic with those already suffering from illness. The sensor will be designed to monitor biofilm growth continuously, based on electrochemical principles. The initial part of the research undertaken at Warwick will be to design an appropriate sensor geometry which is both small enough to fit into the associated tubing but also has the sensitivity to detect and monitor biofilm build-up on the sensor surface. Additional capabilities, such as the ability of the sensor to clean itself, will also be built in. Using personnel at Warwick, skilled in the art of processing diamond materials, inverse electrode structures will be laser machined into sheets of insulating diamond. The diamond will then be sent for conducting diamond overgrowth, and then be returned to Warwick for highly specialised polishing to produce co-planar insulating-conducting diamond structures (the sensor). The sensor will then be electrically contacted and test rigs at Warwick built which replicate the water /dialysate environments of DUWS's and dialysis units. The sensor(s) performance (in terms of an output current) will be monitored continuously and the sensor periodically assessed to ascertain the extent of biofilm build-up on the surface. Simultaneous measurements of microbial content in the water will also be taken. This is in order to relate extent of biofilm build up to numbers of colony forming units, such that it is possible to programme the sensor to notify the user when biofilm activity has risen above a "safe" level.

Planned Impact

The most immediate impact of the feasibility study will be on improvements to patient safety during dental and renal healthcare. With a lack of continuous monitoring, and recognised testing procedures involving bacterial culturing of the water systems taking at least several days to complete, bacterial levels in the water pipes of dental waterlines and renal dialysis units can rise above recommended safety levels during patient treatment. This obviously impacts on patient well-being, more especially so for patients already compromised by illness, as in the case of e.g. renal failure patients.

Moreover, the treatment procedures adopted to clean the systems involves flushing with chemically unfriendly biocides. However, with no immediate feedback on efficacy, too much or too little can be administered. Too little, results in compromises to patient well-being and too much results in unnecessary use of potentially harmful chemicals. In contrast, continuous monitoring using our sensor, enables the right dose to be applied at the right time. Ultimately if the feasibility tests are successful, development of the proposed biofilm sensor, at a commercially viable cost, would result in take up by the international community and capture of a portion of a world-wide market share for a UK-based consortium. This in itself would also impact on job creation in a regionally deprived area; the industrial collaborating SME, Process Instruments is based in the North of England (Burnley).

Although the target market is sizeable, the diamond sensor technology is highly likely to have additional applications directly in biofilm monitoring in other water applications, such as potable water supply, swimming pools, heating/cooling water systems etc. Indirectly, the diamond also provides an ideal platform for the development of other sensors where chemical species monitoring in harsh environments, where diamond wins out over other electrochemical based sensors, is required. The diamond BAA sensor technology is thus expected to impact on, and underpin, a wide variety of applications and technologies that will be unlocked by Innovate UK Biofilm feasibility funding. All parties are committed to developing the diamond sensor technology. A successful feasibility study would also provide the necessary results to galvanise interactions between Process Instruments and both healthcare clinicians and providers of renal dialysis machines and dental unit water systems, in order to encourage take-up.

The biofilm sensor technology will also impact directly on the academic community. Through papers and conference presentations, given during this project, the academic community will be familiarised with developments made in miniaturised diamond biofilm sensing technologies (and related activities). This will act as a stimulant for future research and development into the use of such sensing platforms for a wide variety of different chemical species. This will pave the way for a new generation of diamond based electrochemical sensing devices both in the laboratory and in the commercial world.

Publications

10 25 50
 
Description The aim of the project was to develop a prototype biofilm activity monitoring sensor in a miniaturised format which could ultimately be fitted into water lines associated with dental or renal (dialysis) units informing directly when the systems were becoming contaminated and needed cleaning. We scoped three different designs of sensors - an all diamond design, a screen printed design and a 3D printed polymer design. Only the all diamond design proved robust enough with measurable, low noise signals, The diamond design was selected and then re-engineered to bring the cost of fabrication down to an affordable price. It was shown to function appropriately in model i.e. distilled water and bioreactor feed systems.
Exploitation Route The SME we worked with plan to further develop the sensing technology with a via to commercialisation
Sectors Environment

 
Description We successfully produced a prototype miniaturised biofilm activity sensor capable of producing current signals which alert to the presence of a growing biofilm - this prototype will be further developed by the collaborating SME, Process Instruments (Pi) - leading to job creation and commercial impact
First Year Of Impact 2017
Sector Environment
Impact Types Economic

 
Description EU RESEARCH FRAMEWORK PROGRAMME: H2020 / Marie Sklodowska-Curie Actions
Amount € 4,033,858 (EUR)
Funding ID BREAK BIOFILMS Grant agreement ID: 813439 
Organisation EU-T0 
Sector Public
Country European Union (EU)
Start 09/2019 
End 09/2022
 
Description Royal Society Innovation Award
Amount £250,000 (GBP)
Organisation The Royal Society 
Sector Academic/University
Country United Kingdom
Start 05/2017 
End 05/2019