Professor of Ophthalmic Bioengineering Rachel Williams FIMMM at Liverpool University’s Department of Eye and Vision Science and the Institute of Ageing and Chronic Disease. With over 25 years in advanced materials, she discusses some highlights.
I began to truly understand how we could really contribute to this area of healthcare.
Professor Rachel Williams FIMMM
Professor of Ophthalmic Bioengineering
How long have you worked in ophthalmic bioengineering and what first interested you about this field of study?
I’ve been working in this area since around 1993. I distinctly remember when I had a vitreoretinal surgeon come to see me to ask about the use of silicone oils as tamponade agents for the treatment of retinal detachments. They wanted to understand how they worked and how they could make them work better.
I built some models for them, so they could understand how the oil interacted with the inside of the eye and then we modelled different surgical procedures so that we could work out how they could be more effective. The research led to a long and fruitful collaboration with clinical ophthalmologists and I began to truly understand how we could really contribute to this area of healthcare.
You have designed advanced materials for medical applications for many years now. What are your standout R&D moments?
From the starting position mentioned above, as a team, we have managed to develop modified tamponade agents that are now used in clinical practice to treat patients. This includes a new tamponade agent with an increased emulsification resistance that is also easier to inject into the eye.
Throughout my research I have been involved in multidisciplinary teams, including clinicians, industry, physical and biological scientists, and engineers. For me, this is what makes research in this area so enjoyable.
I am always learning from my collaborators and finding new ways to explain my science to others. I really enjoy seeing how basic fundamental science can eventually lead to a product that can be used by clinicians to treat and help patients.
You currently hold an EPSRC Fellowship on Building Advanced Materials to Treat Vision Loss. Tell me more about this project and what your role involves?
This project has been really exciting. My team have been working on materials for contact lenses, corneal and conjunctival tissue engineering and substrates for the expansion of ocular cells in vitro for future use in tissue engineering products.
Much of this has been based on peptide hydrogels and how we can synthesise them with the appropriate properties for each application. We have also demonstrated that we can manufacture these hydrogels with properties very similar to current hydrogel contact lenses, but with the added advantage that they are antimicrobial. We believe these will be very useful as bandage contact lenses for use after surgery to prevent the risk of infection and increase the comfort for the patient. We have also shown that these hydrogels can support growth of a monolayer of corneal endothelial cells and that they can be transplanted into the anterior chamber of an eye.
We are developing these further for the treatment of corneal endothelial disorders, which are currently treated with a corneal transplant. The hope is that, using our peptide hydrogel, we will be able to use one donor cornea to treat several patients.
Why is it so important to assess the properties of structural biomaterials in medical applications?
The properties of biomaterials need to be optimised for the specific application that they are to be used in. This includes their physical, mechanical and biological properties. If any one of these is not appropriate, the device may well fail. For example, a particular material may have excellent properties for one medical application but could be completely inappropriate for another – sometimes we want a material to degrade after a certain amount of time, other times it has to be in the patient for the rest of their life. It is essential that we understand all the unique details of those interactions when dealing with biomaterials.
You received the President’s Prize from the UK Society for Biomaterials in recognition of outstanding contributions. What single achievement are you most proud of?
That is a very difficult question because I don’t think anything is really a single achievement. My research and its success has always been a team effort and I am probably proudest of the way my teams have worked together to produce results that have led to greater understanding of the way materials interact with the biological environment, and how we can use this understanding to develop new ways to treat patients through working with our clinical colleagues.
Can you tell me more about the antimicrobial nitric oxide releasing contact lens gels for the treatment of microbial keratitis – an infection on the cornea? What stage are you at with the work?
This research is being led by my colleague and Senior Lecturer in Anti-Microbial Biomaterials Dr Raechelle D’Sa, who has developed a novel technology that promotes the release of nitric oxide from amine-containing materials.
We demonstrated that our peptide hydrogels contact lens material could be functionalised with these nitric oxide releasing groups and that these show good antimicrobial properties against bacterial strains that cause microbial keratitis.
So far, the challenge has been enabling the nitric oxide release to be active for a long enough time period and at a level that is non-cytotoxic. Our results are very encouraging but have so far all been in vitro.
What are some of the pros and cons of working in your field?
The pros of working in this field are the multidisciplinary nature of the research and the fact that, ultimately, it is very clear that if successful there is a real need and benefit to society for your work. The cons include some of the frustrations during research, so when the exacting nature of the properties needed just cannot be reached. For example, a material may have excellent properties but cannot be sterilised or cannot be surgically implanted using the instruments available to the surgeons.
It can be a long process to go from early stage to commercialisation in such a delicate field of engineering, with clinical trials and multiple stakeholders involved in the process. How do you overcome that?
You’re right. It can take a very long time to take a material from the initial idea, through the scientific development, then the regulatory process to final commercialisation and clinical adoption. I have only achieved this with the silicone oils and this was simplified in many ways because the material was a modified silicone oil.
To achieve the same result with a completely new material, it would have taken much longer and been considerably more expensive to develop. But I think you have to keep in mind that all the development along the way has outputs, that have the potential to have benefits for other devices and even in other fields.