Molecules that can be specifically controlled open up new possibilities for materials and applications in medicine. Researchers are working on this in the Collaborative Research Center (CRC) 677 "Function by Switching". The research partnership ends this year. unizeit spoke with CRC spokesperson Professor Rainer Herges.
Molecular machines, as they have been researched in the CRC, have tremendous potential. The Nobel Prize for Chemistry was even awarded in this field of research in 2016. What makes this topic so exciting?
Rainer Herges: Switches are an elementary step in engineered machines such as motors, pumps or sensors. In the past, their miniaturization has led to greater efficiency, like in microelectronics. The limit of miniaturization is the molecular switch, which can be used to implement complex functions at the nano level. This is what I personally find so interesting about chemistry: you can create your own molecular world.
The CRC has produced results that are highly respected internationally. What do you consider the most important ones?
It is difficult to highlight individual results. For example, we have produced the first molecules that can be switched between a magnetic and non-magnetic state at room temperature. In another project, we discovered a new form of catalysation: an effect that accelerates the speed of molecular reactions by three orders of magnitude. Used properly, it could be used to catalyse and remotely control reactions. Other discoveries that are at least equally important have been made in other areas of fundamental research.
What were the greatest challenges?
For concrete applications, a switch must fulfil certain properties and be able to be manufactured to order. Designing certain molecules, known as synthesis in chemistry, can be imagined as follows: you have four quadrillion wheels and one quadrillion chassis. You put them in a big box, give them a shake and the cars build themselves. So you need to prepare the individual components so that when "shaken" – that is, when heated or exposed to light in the lab – they can automatically find each other and know what they need to do. This rarely works the first time.
It sounds like you need a lot of perseverance.
And tolerance for frustration – that is a hallmark of a chemist (laughs). One absolute necessity is fun, so that you can set aside the failures. As a scientist, you have to keep a sense of childlike curiosity. As a child, for example, I took apart my model train set instead of playing with it, because I wanted to know how it worked.
Over 100 scientists from the fields of chemistry, physics, materials science and medicine worked together at the CRC. How important is this interdisciplinary approach?
For a challenging project like this, you need expertise from other areas of specialization. Chemistry, for example, provides more of an engineering component, while physics likes to break down phenomena to their fundamental principles. This makes for very fruitful symbiosis.
Besides fundamental research, your association also plays a role in applications. Where will we find switchable molecules in everyday life?
We can now move particles without contact, using light, even in solutions. For example, as a switchable contrasting agent that can be activated in the body on command. This allows the measurement of temperatures in deep tissues using MRT, or heat sources in materials science. It will be a while before this is used in medicine though. The CRC has also produced two start-ups, including one for a special light technology for scientific experiments.
CRCs are considered to be exemplars of top-level research. What benefit does a university have from them?
Collaboration is possible without CRCs, of course, but they do make many things easier. In national and international competition, this funding instrument is likely to become even more important. Among other things, they help universities to continue structural development. Since 2013, we at the CAU have had a new research focus in nanosciences with KiNSIS. In a way, interdisciplinary cooperation in the CRC was the nucleus for this.
Even though financing has stopping now that the maximum funding duration has been reached, surely some questions remain unanswered. What comes next?
Research topics change over such a long period of time. Twelve years ago, we were among the first to enter a field that was still relatively unknown. More individual projects and small research associations that have grown out of the CRC are in the planning stages.
How is a CRC founded in the first place?
At a faculty summer party, we talked about our work and found that we had a lot in common. Over the next few months, more and more people became interested and joined us. It was a process driven by its own internal dynamic. Good scientists who can inspire others are the most important aspect.
The interview was conducted by Julia Siekmann.
Collaborative research centres (CRC) are interdisciplinary research associations established for a maximum of twelve years. The German Research Association (DFG) uses them to finance innovative, challenging, and complex projects of high scientific quality at the international level. The Kiel CRC 677 was subsidized with a total of almost €30 million from 2007 to 2019. jus