Probiotic, biocide-free antifouling coatings based upon sol-gel encapsulated micro-organisms

It is interesting to speculate that Nelson's victory at Trafalgar was due to an absence of biofouling on the ship's hulls (which were made of copper, a known biocide) allowing them superior speed.Biofouling is the undesirable accumulation of microorganisms, algae etc which occurs on submersed structures. The effects of biofouling are considerable; increased frictional drag, leading to increased fuel consumption and associated CO2, SOx, NOx emissions; restrictions in internal pipe dimensions leading to loss of flow, increased pressure and poor heat exchange in pipelines and commonly, the development of biofilms that provide habitats for the development of aggressive micro climates that are extremely acidic and lead to rapid rates of corrosion and structural failure, e.g., BP Purdoe Bay pipeline failure was due to microbial induced corrosion (MIC).The aim of this project is to commercialise a non-biocidal antifouling coating. The coating is based upon the concept that 'protective bacteria' encapsulated within a sol-gel matrix, and applied to a surface, will prevent harmful biofilms forming on that surface. The 'protective bacteria' in this case consist of endospores that are naturally ocurring in soil and are non-pathogenic. The concept has been proven in an EPSRC project that will end in October 2010.We propose to work with selected partners who manufacture coatings for the key markets that utilise antifouling coatings. The partners will help with commercial performance testing that will allow us to benchmark our coating against current commercially available coatings. We will address the requirement for the coating to be applied under industrial conditions to large surface areas and the feasibility of applying our coating on top of existing marine coatings that are applied to prevent corrosion. Importantly we will address the issue of scale-up of manufacture, particularly that of endospore production, something that traditional coating manufacturers are not familiar with. The partners will also advise on Health & Safety issues and provide guidance on regulatory requirements of the coating.

The aim of this project is to develop a non-biocidal antifouling coating. To this end the main beneficiary is society. Current antifouling coatings rely primarily on the release of a toxic compound from the coating. Accumulation of these compounds within the environment has long-term consequences for the eco-system. This is particularly true when ships are docked and the dilution factor that normally reduces the concentration of harmful substances when the vessel is in an open sea or ocean, does not occur. As environmental legislation restricts the use of harmful biocidal coatings, the potential for micro and macro-fouling on surfaces increases. With this comes economic penalties such as increased fuel costs for global shipping and increased maintenance costs to remove fouling across a wide range of industries. The development of an alternative non-biocidal coating offers the opportunity to prevent such economic penalties without impacting upon the environment. Therefore a successful outcome for this project will for example, benefit coatings manufacturers, who will maintain a market for their products and global ship owners who will benefit from reduced fuel consumption (with a societal benefit of reduced greenhouse gas emissions) and increased productivity as vessels spend less time in dry dock having fouling removed from surfaces. Other beneficiaries include those industrial sectors where biofouling impacts upon the performance of a process and the maintenance costs, for example, transfer of liquids in pipelines, heat exchanger systems, bioreactors, solar panels and anti-mould construction panels.