MESA+ University of Twente
Research Business & Innovation About MESA+ Education

Volume 1, 2012

Brush maker

Nano polymer brushes, polymer brushes attached to spheres, polymer brushes that collapse on command. Young polymer chemist Xiaofeng Sui knows all there is to know on this subject. “I hope to become a professor in ten years’ time.”

In the trainee research assistants’ room of Julius Vancso’s MESA+ department of Materials Science and Technology of Polymers, Xiaofeng Sui pushes a collection of publications towards me. They are his publications. Quite an impressive collection for someone who has only been engaged in research for three and a half years.

Why are you conducting this research?
“Because I find research into polymers and polymer brushes one of the most interesting areas of science.” You can vary the size of polymers, you can use polymers separately or as gel, you can attach them to small spheres, and you can manipulate them. This research also leads to some amazing applications.”

What sort of applications?
“For instance, I have made polymers for use in cell cultures. In other words my polymers can be used as a substrate for cell cultivation. I have also made polymers that can be used to deliver medicines.”

Polymers that deliver medicines?
“Yes, we can make spheres from polymers and have them burst open at exactly 37 degrees or at a certain acidity level. You can place medicine inside it or attach the medicine to the outside of one of these spheres and when ingested by the patient you can have it burst open at the exact place where you want the medicine delivered.”

You have also made antibacterial polymers. Why?
“You can use our antibacterial polymers to promote bone material growth for example, and subsequently introduce that bone material into a patient’s body. You don’t want bacteria to grow through it because that would obviously infect the patient. These polymers contain nano silver particles that ensure the antibacterial effect.”

What do you hope to have achieved in ten years’ time?
“I hope to have become a professor by then. I certainly want to continue my career in the scientific world. First as a research student and then as the leader of a small research group, then a professorship. But first things first – I have to defend my PhD thesis in June!”

Yin and Yang

To explain the research he is engaged in, polymer chemist Xiaofeng Sui draws a diagram consisting of a circle divided into eight segments. In the middle of the circle is a Yin and Yang symbol. Xiaofeng Sui: “I chose the Yin and Yang because it’s a symbol that represents dynamism, movement, reaction and counter-reaction. My polymers are just that. They can change shape, change colour and can even change their solubility. They adapt to their surroundings and are constantly in motion.’

From top to bottom counterclockwise.

1. Individual polymers.
2. Polymer brushes.
3. Mixed polymer brushes.
4. Polymer brushes with typical patterns.
5. Gel polymer brushes.
6. Macroscopic gel networks.
7. Mixed gel networks.
8. Microspheres and nanospheres of gel and polymers.

Name: Xiaofeng Sui (1983)
Position: Trainee research assistant (defence ceremony on 29 June 2012) at the Materials Science and Technology of Polymers department
Previously: obtained his master’s diploma in polymer chemistry at the University of Tsinghua in China in 2008, has already been awarded several prizes during his study, and was presented with an ‘award for outstanding selffinanced students abroad’ by the Chinese Government in 2010
MESA +... ‘is collaborating: I have worked together with other MESA + groups on all my publications’