Her supervisor Patricia Dankers thought it would be something her: Faces of Science, an initiative by the Royal Netherlands Academy of Arts and Sciences in which young researchers show what it is like to be a scientist. “Back then the idea of presenting something still terrified me, but she was confident I could do it,” Dan Jing Wu tells us, laughing. “She recognized that quicker than I did.”

As it turned out she did have a flair for public speaking. One thing led to another: taking part in FameLab and the University of the Netherlands, an international art project on a ‘human vase’, involvement in the Dutch National Research Agenda, guest appearances on radio and television. Wu turned explaining her research for a wide audience into one of the aims of her doctoral study - she even devoted a chapter in her thesis to science communication. “It is important, I believe, to give young people a little insight into science. To help them see if it might be something for them.”

As for herself, until she graduated she had never thought she would study for a doctorate. “I'm no Einstein; I didn't think I was smart enough to become a scientist. But doing research is also very much about creativity and perseverance.” And these qualities she certainly has. As her supervisor Dankers also recognized, Wu points out. “Actually, she gave me a completely free hand. That was very welcome but at the same time a little daunting.”

Artificial heart

Wu’s dream is one day to get a working heart rolling off a 3D printer. “We can already produce structures of synthetic material that serve as a sort of scaffolding within which the body's cells can grow,” she explains. In time this ‘bioplastic’ simply disappears, leaving a piece of muscle, blood vessel or heart valve. The next step is to make the material dynamic: so that it can bend or contract under the influence of a particular stimulus. Like the light-powered ‘walking’ plastic that has been developed elsewhere at TU/e.

“Based on a biomaterial that had been designed sometime previously at Biomedical Engineering, I produced what we call a hydrogel that shrinks or expands depending on the temperature. In principle it is a soft, transparent kind of plastic, but in hot water it shrinks and turns white. This happens when the water molecules locked into it are expelled. Immerse it afterwards in cold water and the reverse effect occurs.”

And no, this is not the ideal material for an artificial heart, which would have to do its job at a constant temperature of roughly 37 degrees. As Wu well knows. Nonetheless, her invention is valuable, she thinks. “It turned out to work very differently than we had expected at the outset; that means we have learned something new. Which is both frustrating and exciting. As we are keen to gain a better understanding of how it works, I am now doing follow-up experiments.”

Closer to an application is a new technique for printing plastic blood vessels, something Wu says grew out of a ‘Friday afternoon experiment’; a hobby project, as it were. Repeatedly taking tiny steps alternately on the x and y axis is the way to go, she explains, if you want to print rounded shapes with a 3D printer. The smoothness of the curves depends, thus, on the resolution of the printer: the coarser this is, the more jagged the printed form. Together with technician Jurgen Bulsink she devised a way to attach the print head to a rotating rod.

“This allows you to print smooth spiral forms. We applied this method to plastic blood vessels, so that they don't kink when you bend them double. Just think of a vacuum cleaner hose.” Flexible artificial blood vessels like these can be very useful to the vascular surgeon grafting on a bypass. “With the involvement of Utrecht University these ‘anti-kinking vascular grafts’ are already being tested in animals.”

Swept along

On April 30th she will defend her thesis, having put back the date a few months in the hope that family and friends would be able to attend. Only a week in advance it became clear that under the current corona measures this would indeed be allowed. “Weighing up against that, I have had more time this past year to write my thesis than would have been the case without corona. I was used to planning every minute of my day and only coming home to sleep.”

Aside from her doctoral study, Wu has boxed competitively and was used to having a busy social life. She and a friend also run their own bag label, NOYA NOIR. “Whatever came along, like any chance to promote my research, I always grabbed it with both hands. I've gained lot in this way, but it became a bit too much. Like the time I got home from Hilversum at 4 o'clock one morning after doing an interview on nighttime radio and the next morning was back in the lab at 9 a.m. In that respect, it felt good to stop being swept along and get back in the driving seat of my own life for a while.”

All the same, Wu, who spent a swift six months studying Industrial Engineering and Management Sciences before switching to Biomedical Engineering, and who later brushed up her skills at TU/e Innovation Lab, has since returned to very busy mode. She is currently setting up a company working with synthetic biomaterials from the lab of her supervisor Patricia Dankers. “So that we can accelerate the adoption in clinical practice of developments made in growing tissues in the lab.”