Professor Mohan Edirisinghe
Biomaterials Processing Laboratory
Department of Mechanical Engineering
University College London
RESEARCH INTERESTS
We are engaged in internationally leading materials processing and forming research addressing some of the global manufacturing and healthcare challenges. External research sponsors include the UK Research Councils (mainly EPSRC), Orthopaedic Research UK, The Royal Society, The Wolfson Foundation, The Leverhulme Trust, The Islamic Development Bank, The Danish Agency for Science, Technology & Innovation, The Worshipful Company of Armourers and Brasiers, The British Council and several industries. Recently, the Governments of Kuwait, Turkey, China, Indonesia and the UAE have funded our work by sending doctoral scholars. We enjoy close ties with the Healthy Infrastructure Research Group of UCL Department of Civil, Environmental & Geomatic Engineering and the UCL School of Pharmacy with whom we have a special relationship.
We cherish several national and international external research collaborations, in particular with Oxford University, Cambridge University, Queen Mary University of London, University of Hertfordshire, University of Greenwich, University of Sheffield, Napier Edinburgh University, Queens University of Belfast and universities in the USA (in particular Kansas, North Dakota and North Carolina), Turkey (in particular Hacettepe University and Marmara University), Italy (in particular Padua University), China (in particular China University of Geosciences, Beijing, Dalian and Sichuan), Japan (National Institute for Materials Science, Ibaraki) and India (IIT Gandhinagar). We work very closely with UCL Business and industry, in particular BASF.
The group, (about a dozen in total) and laboratory specialises in creating smart coatings, smart fibres, bubbles, vesicles, droplets, particles, capsules using a variety of new devices/processes invented in our laboratory. We specialise in soft matter and have patented these inventions. Our work has led to many accolades and in 2023, The Royal Academy of Engineering and The Royal Society have awarded medals for our work.
Key Projects
1: Exploration of Gyration Techniques
The creation of a family of novel gyratory forming methods for polymeric fibres and microbubbles with industrially attractive yields gaining huge manufacturing advancement in key areas such as antimicrobial resistance, tissue engineering has generated significant impact, with three EPSRC responsive mode grants worth £1.5 million awarded in the last few years. Pressurised gyration was patented and featured on the front cover of Macromolecular Rapid Communications in July 2013. This process which can also create microbubbles (see front cover of Langmuir) was supported by BASF and bio-pharma companies (e.g. Astra Zeneca) and an EPSRC manufacturing research grant. It generated substantial international interest particularly in USA and China. This has subsequently led to the creation of many other gyration-based sister-processes which have also won many front covers in leading journals, as illustrated below.
We are also developing a new pressurised gyration device to manufacture sutures, which lead to a paper by UCL PhD scholar Esra Altun in ACS. To boost manufacturing for healthcare in collaboration with the University of Sheffield, we are harnessing the benefits of polyhydroxyalkanoates with pressurised gyration to boost hard and soft tissue engineering.
Enormous industrial interest has been aroused to win a large industrially-backed EPSRC healthcare grant which investigated the manufacture of a new generation of antimicrobial filters for healthcare. The gyratory fibre-mats are also proving to be very successful in the development of tampons for vaginal drug delivery and in the development of artificial bone marrow fibre scaffolds. Gyratory forming is being extended to include graphene, wound healing bandages and a variety of drug delivery patches combining antibiotics and nanoparticles. In a more recent development, we were awarded an EPSRC grant to extend pressurised gyratory manufacturing to core-sheath morphologies. In 2023, we published an invited feature review articles on the development of pressurised gyration: see paper 1 and paper 2. Extended facets of the core-sheath work is still in progress, it has created new devices and been the focus of much media attention. For example, we have extended its capabilities to antiviral mask manufacture to join the anti-Covid-19 battle, supported by the Royal Academy of Engineering. This has gathered an interest in Covid-19 causing variants, reviewed in Advanced Science. This work has led to extra funding from the governments of Kuwait, Turkey, Indonesia and the UAE, which has already resulted in key papers in IF 19 Applied Physics Reviews, see paper 1 and paper 2. This is only the start, much work is currently in progress to further develop layered fibre manufacturing.
Two new facts of pressurised gyration research come from our collaborations with Queen's University Belfast and Napier Edinburgh University. In the former, we are making self-healing thermoplastic polyurethanes for wearable materials technology and electronic skin textiles. In the latter, we are using nanocellulose derived from natural materials and waste to make fibrous membranes and films. Here we are using pressurised gyration (horizonal axis rotation) and jetting directly into water to create the fibres from nanocellulose.
2: The use of Electrohydrodynamics: Multi-layered Microbubbles, Particles and Fibres
We are also the first in the world to make 4-layered particles and fibres as featured on a journal front cover and the particles are being trialled to treat UTI in new ways as featured on another journal front-cover (see below). It is also being exploited commercially to treat urinary tract infections. We were invited by Langmuir to review the progress in making and using microbubbles: Microbubbles: A New Medical Frontier. New research into the exploitation of microbubbles has also progressed in collaboration with Turkey, India and Finland/Japan. The work with India has progressed even further with several publications on microbubbles in Langmuir: paper 1, paper 2, paper 3, paper 4, paper 5.
In collaboration with UCL School of Pharmacy and industry, have developed a new portable electrohydrodynamic gun-device to deposit wound dressings and drug delivery vehicles/patches. This initiative originates from our previous work (watch video below) and has received substantial EPSRC funding. The aim is to miniaturise the "EHD Gun" to a device in a paramedic backpack.
The electrohydrodynamics research now focusses on graphene and its derivates in collaboration with University of Oxford (Dr. Tanveer Tabish). It is also being extended to our graphene-based point-of-care healthcare devices, in collaboration with the USA, Japan, and in addition, triboelectric biosensor applications with Loughborough University.
EHD Gun
3: Sustainability and Natural Materials
Together with Napier University in Scotland, we are exploiting natural materials such as cellulose by using developments in nozzle pressurised gyration.
Recently, we used pressurised gyration to form bandage-like fibres with casein, a low cost and environmentally-friendly by-product of milk production. We tested these bandages in animals and found that at 14 days the wounds treated with casein-infused bandages healed to 5.2% of their original size, compared to 31.1% in the normal bandage group and 45.6% in the untreated group. This was picked up by national news outlets including The Independent and The Standard.
We are also working to remove ourselves from our reliance on grid power. Grid power is often created by unsustainable sources and subject to large price volatility. We are therefore developing a pressurised gyration setup which operates from battery technology only. Battery technology allows for the store of energy that can come from more sustainable sources such as solar and wind power.
We are also conscious of the fact that polymer forming has to face up to global challenges and have pioneered strategies to address these issues specifically: Environmental Impact of Polymer Fiber Manufacture & A Global Challenge: Sustainability of Submicrometer PEO and PVP Fiber Production.
4: SANTA Project
Supported by EPSRC, this project in collaboration with The School of Pharmacy at UCL has led to incorporation of AI in electrospraying and electrospinning. With the rise of “nanomedicine” through the nanotechnology-enabled vaccines during the recent pandemic, there is a pressing need for advanced manufacturing technologies that can overcome the challenges of large-scale good manufacturing practice (GMP) production. Conventional methods for synthesizing pharmaceutical nanoparticles are limited by poorly characterised batch reactors, whilst relatively new technologies with flow systems in small (micrometre) scale enable precise control over nanoparticle features. Electrohydrodynamic (EHD) processes are a collection of state-of-the-art fabrication techniques that can generate structural features in micron to nano-size. Despite theoretical models and simulations to understand the mechanisms involved in EHD were developed, large-scale production with EHD is still hindered by the complex behaviour of the electrified jets and the lack of predictive models that encompass a plethora of process parameters. In addition, translation of the EHD process into industry is limited by human resources that possess expertise and multidisciplinary knowledge. This project aims to use machine learning (ML) as an extension of Industry 4.0 to regulate the key EHD process parameters as well as the workflow to achieve a sustainable manufacturing process and machine intelligence. Predictive and optimization ML algorithms will be developed to facilitate process monitoring and quality control through in-line systems and automation. The work is already leading to high impact publications, e.g. in Small Science .
5: Other
We are also working on another set of projects with Professor Anthony Harker and Professor Yiannis Ventikos (on modelling our processes and inventing related but new approaches). Collaborators with internationally leading clinician Prof Shervanthi Homer-Vanniasinkam has been successful and is expanding. We are also seeking combined and more efficient industry-backed manufacturing processes and early work to seek funding has already begun. For example, Jubair Ahmed is leading efforts to combine gyratory and electrohydrodynamic processes to make healthcare bandages with robotic control, in collaboration with Prof. Helge Wurdemann and Prof. Shervanthi Homer-Vanniasinkam.
In the antimicrobial domain, we have new collaborations with UCLH and the University of Hertfordshire to address the spread of Pseudomonas in shower heads by developing new filter technology.