Professor Pavel Matousek is a STFC Senior Fellow at the Central Laser Facility, whose Octopus, Artemis and Ultra labs are based here at the Research Complex at Harwell. Since 1991, Professor Matousek has worked at the Rutherford Appleton Laboratory in the area of nonlinear optics and vibrational spectroscopy. He proposed the use of Optical Parametric Chirped Pulse Amplification (OPCPA) for the generation of multi-petawatt peak powers, pioneered the concepts of Kerr-gated Raman and Spatially Offset Raman Spectroscopy (SORS) and introduced transmission Raman spectroscopy (TRS) into pharmaceutical analysis.
Pavel has published over 200 peer reviewed articles, filed 10 patents and co-edited a book on Raman Spectroscopy (with Prof. Michael Morris, University of Michigan). Pavel is also a founding director of Cobalt Light Systems Ltd established to commercialise SORS and TRS technology.
This week marks British Science Week and Alison Oliver, Communications and Engagement Officer at the Research Complex at Harwell, talks to Professor Matousek about his career so far, from starting out on Harwell campus during his PhD to his team's pioneering work in spectroscopy.
What nurtured your interest in physics as a discipline and what led you to study the subject at Czech Technical University?
I was interested in maths and physics from an early age and both subjects felt natural to me. I was particularly interested in astronomy and joined a club at the time. I found physics practical and maths abstract. Lasers caught my eye during my teens and I decided to study at Czech Technical University as their course included laser physics.
You have been working here at RAL since 1991. What led to your journey here?
There was a research associate position here, which entailed a three year stay working in the lab and would form part of my PhD. It was the opportunity to work at a world-renowned laboratory. Since the very beginning, I was working on Raman spectroscopy in various aspects and I think this contributed to my decision to stay here at Harwell. There is such a diversity of research here, with the ability to work on so many different areas and with such great colleagues. The focus on research helped me settle here and the move felt right. I first rented a room in the former barracks here on campus, before eventually settling in Cumnor. Here I am still, 31 years later!
As a Senior Fellow at STFC, what does your role entail?
For many years, I've been a station scientist. I worked on Central Laser Facility's Ultra system here at Research Complex, and with UKRI there are two pathways, managerial and individual merit, the latter of which allows one to devote a significant time to research. The science motivated me and it was how I felt I could contribute best, so I'm known as an individual merit scientist. This really unlocked a lot of pathways for me and I was able to engage in multiple disciplines that led me in so many new directions.
You have achieved an immense amount of ground-breaking research including pioneering ps-Kerr gating for fluorescence rejection in Raman spectroscopy, proposing Spatially Offset Raman Spectroscopy (SORS) and introducing Transmission Raman Spectroscopy (TRS) into pharmaceutical analysis. What was it that led to each of these achievements?
It's been really thanks to working in collaboration with so many excellent colleagues in such a vibrant, multidisciplinary environment, which in turn, stimulates your thinking and brings you to pathways you hadn't thought of. All of these were achieved in close collaboration with many of my colleagues at the Central Laser Facility over many years, including Tony Parker and Mike Towrie.
Research Complex is a great example of such an environment where multiple disciplines come together, which would not happen if you were working in isolation. In fact, if I look back, a lot of these ideas began over a coffee, rather than a formal setting.
Which of these techniques would you say has had the most impact so far?
I think it would be the development of spatially Offset Raman Spectroscopy (SORS) which originated from research at Ultra facility, stationed here at Research Complex. SORS is based off the existing technique, Raman spectroscopy, which is named after the Indian scientist who discovered the technique in 1928 and won a Nobel Prize. SORS is a depth-profiling technique that permits chemical analysis of subsurface layers for a variety of materials. It takes advantage of the Raman spectroscopic fingerprint of molecules to enable chemical specific identification and quantification of materials that lay beneath the surface, up to several millimetres.
My colleagues, including Tony and Mike, and I observed a strange phenomenon in an experiment commissioned by ICI (Neil Everall) which was a hindrance as to what we wanted to do. We investigated this phenomena and its physical origins and we realized that the physics of this particular process, which was impeding our measurements, actually could be utilized for the benefit of seeing through various barriers. We could now see biological tissues in depth and derive the chemical structure without having to cut into these tissues. For example with plastic bottles, most of which you cannot see through, simply by shining laser light inside, we could analyse their chemical composition. That is the basis of SORS, shining a light onto something and being enabled to not only see it from the surface but what it is made of inside, by observing photons bouncing back of different colours at different locations.
SORS allows you to go deeper with this technique which was not possible before. For example, you can use SORS to detect a disease or indeed its absence, or monitor the effect of treatment inside our bodies by non-invasive means. This led to a new direction in research for me which provided the foundation of my fellowship activity in 2004.
In 2008, you co-founded Cobalt Light Systems Ltd and was its Board Director and the Chief Scientific Officer (CSO). How did the discovery process of SORS lead to the development of Cobalt?
Cobalt Light Systems was a spin-off company in partnership with my colleagues and our business department at STFC. We were strongly supported by management at CLF and this formation led to the creation of new scanning devices based around the SORS technology. Over 500 of these devices are now operational worldwide in airports. If you wish to take more than 100ml of liquid on board a flight, the liquid will be scanned by these devices e.g. milk for babies or essential medicines that you need. Pharmaceutical manufacturers also use these devices to check the authenticity and correct formulation of medicines before being released for distribution. These particular applications were subsequently acquired by Agilent Technologies about four and a half years ago, who also now have a building on Harwell campus.
On a personal level, it was particularly gratifying to see that something tangible can happen from the science that we were doing and at the same time, this particular discovery led us to opening new directions of research which, whilst not yet commercial, are forming part of my activities here at STFC.
This treatment could hopefully be potentially viable in the future and is a fantastic collaboration with my colleague, Nicholas Stone who leads the project, Raman Nanotheranostics (RaNT).
“The impact of COVID-19 enabled everyone, not just myself, to strongly realise that the vibrant environment and collaborative research at Research Complex is partly due to informal discussions taking place over coffee and in corridors."
Your current research areas include non-invasive disease diagnosis, security screening, forensics, cultural heritage and pharmaceutical analysis. What are you working on at the moment and how has the pandemic affected your research?
Right now, we are working on a very exciting project with the universities of Exeter, Cambridge and UCL, to utilise this technology in conjunction with five other technologies in order to diagnose and treat cancers in patients is a simultaneous procedure. This is called Raman Nano Theranostics, which is an EPSRC project funded at £5.7 million for five years.
I am also working on bone diagnosis with UCL and assessing medicine quality with Oxford University.
During these past two 'COVID' years, I have realised how very important informal conversations are. When COVID-19 hit, we were working from home and we lost those conversations both at work and at conferences. We did meet via Zoom, of course, but these were meetings to discuss a particular subject or issue, whereas the unstructured chats over coffee could be about anything. You could no longer pass someone in the corridor to stop and chat informally about research.
The impact of COVID-19 enabled everyone, not just myself, to strongly realise that the vibrant environment and collaborative research at Research Complex is partly due to informal discussions taking place over coffee and in corridors.
Your work has also included art restoration. Please could you tell us further about your endeavours in this area?
This is again using SORS, in combination with microscopy, in order to provide information about the composition of an object, which could be a painting, sculpture or fresco. The goal is to identify the chemical composition of sublayers. These objects are very often covered in multiple, painted layers, which has occurred, often over centuries, as people would regularly overpaint the art objects purposely in order to restore them. Alternatively, the object was originally painted in a multi-layer system. In the restoration process, you need to understand what these layers are chemically made from because if you apply the wrong chemical to an object of art, you can destroy it. With methods, you can easily ascertain what the surface layer is made out of but it is much harder to see the deeper layers.
I work with ISPC-CNR, a research council unit in Milan to develop the micro SORS technology for this specific purpose. This arose from discussions in a corridor at a conference in Boston when a researcher (Claudia Conti) approached me about her ideas. For examples, frescos can be overpainted with a hidden painting underneath. With sculptures, we are finding five or more layers underneath in some instances.
How does being based at Research Complex help your work?
Research Complex has a very rich interdisciplinary environment which I have always valued and for me, there is a natural synergy as much of my work has been at Ultra, which is located here. We can investigate various aspects of Raman spectroscopy but also it is fantastic to collaborate with the Catalysis Hub on site and be able to easily discuss various ideas or opportunities together. Research Complex is an example of one of the many fantastic facilities to have emerged at Harwell Campus over the years since I first started to working at Rutherford Appleton Laboratory, with people from different disciplines conducting various experiments under one roof and on the same campus.
My work has taught me that if you come across an issue or anomaly in your data, don't just dismiss it…investigate the issue and try to understand it, as it could potentially be useful somewhere else. This is often how new discoveries are made…That is exactly how we came across SORS. So these days, when I come across something unexpected, I stop and try to understand even more.
You are an Honorary Professor at University College London and Honorary Visiting Research Fellow at Oxford University. What do these roles entail?
They are long-term engagements where I am involved in various research projects. With Oxford, I am looking into techniques to examine the quality of medicine with Paul Newton and others. With UCL, I am conducting research into bone disease with Tony Parker at STFC and Allen Goodship from UCL. With Exeter, I have had a strong collaboration for 20 years, working on medical applications for cancer diagnosis with Nick Stone.
What has been the biggest lesson you have learnt in your career so far, and the subsequent advice you would then pass onto others working within this field?
Certainly, my work has taught me that if you come across an issue or anomaly in your data, don't just dismiss it. So, lesson number one would be to investigate the issue and try to understand it, as it could potentially be useful somewhere else. This is often how new discoveries are made. You come across something unexpected that may appear unrecognizable or as some problematic result from your experiments. But if it does happen, it is worthwhile to spend some time to understand why that happened. That is exactly how we came across SORS. So these days, when I come across something unexpected, I stop and try to understand even more.
Lesson number two is perhaps that there are many areas of science which are still to be discovered. When you have finished your university and are starting out in your first job in a lab, and you observe the amazing work that is going on around you, you can feel overwhelmed and discouraged. You think to yourself that surely by now everything must have been discovered. It was certainly how I felt and I have heard friends and colleagues say similar. With the benefit of hindsight now, I would say there are so many undiscovered areas, especially in multidisciplinary research, where you are combining one subject with another, utilizing the expertise of people from different fields. Science is becoming increasingly collaborative. If you look at my list of publications, you will see that many of my co-authors are from different disciplines. Collaboration is what I find exciting and what drives me still to this day.
You have co-authored over 200 publications. Is there a particular article that you are most proud of?
One example might be research in collaboration with colleagues on Kerr gated Raman spectroscopy which was my first grant of £99K but because it's your first grant, you, naturally, try very hard not to fail! It was a risky business and when I saw the proposed theory working, that was a really memorable moment. It's that moment in the lab when you see your research working and you feel relief and happiness. It must be true in any discipline when you discover something new or you reach a breakthrough.
With the highlights of my career, those moments we discussed from your earlier question are powerful moments in my life. Every five years or so there was a breakthrough of that kind and it gave me the encouragement and drive to move onto the next. There was a huge amount of contributions from so many people. That's why I'm also so sensitive to something unexpected as it can lead you down a path to new discoveries. Many times it's nothing, but problematic data or seemingly artefacts are not such the nuisance that they were to me before. They are a pointer. Not every problem will be worth pursuing but once in a while, it may be and that impact can be huge, as I indeed was lucky to find!
Finally, your work in three words.
Exciting, diverse and, hopefully, sometimes impactful.
Image appear courtesy of Professor Matousek. Photographer: Rob Lacey