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Jan O. Jeppesen

Professor

Phone: +45 66158780, +45 65502587
Email: joj@sdu.dk
Webpage: http://www.jojgroup.sdu.dk/index.xhtml

In my research group, we use organic synthesis and supramolecular chemistry to develop new functional materials that can be used in future technology. Molecular machines are systems that consist of different components that can be made to move in relation to each other, while molecular sensors can be used to track other molecules, such as explosives or narcotic substances.

Studies of artificial molecular machines are, among other things, important to gain a better understanding of the functioning of the complex machinery and motors used by nature in organisms such as the human body. The molecular machines we work with are called rotaxanes. Overall, rotaxanes consist of a rod, which is bordered by a ring, and at each end of the rod sits a stopper that prevents the ring from slipping off. The ring can move between two positions on the rod and we can decide when to move it. The rotaxane molecule is manufactured using synthesis chemistry in a chemical laboratory and is made by putting smaller building blocks together, one for one, as Lego bricks. Currently we work on an exciting project, which is to produce molecular machines that will be able to expand/pull together using appropriate external influences. Such systems can be perceived as molecular muscles, imitating the movement that takes place in the body's muscles. This will in principle allow the transformation of electrical energy into mechanical energy and produce a system consisting of approximately one trillion molecular muscles per square millimeter, which synchronously will be able to collaborate on lifting an object.

The increasing focus of recent years on landmines and terrorism has created a need for the development of fast, inexpensive and reliable methods of detecting explosives. In my group, we have designed and synthesized a molecular sensor that, using a simple color switch from yellow to green, signals that it has detected the explosive TNT. The sensor is unique compared to the methods that are usually used for detecting explosives, as it is very selective and thus is very reliable. However, it has the weakness that it is not particularly sensitive and thus cannot trace very small amounts of explosives. At the moment we are working to resolve this issue by developing new detection platforms that can amplify the signal emitted by the sensor when it comes into contact with explosives.

 
Group webpage: Jan O. Jeppesen
 
A complete list of publications by Jan O. Jeppesen can be found here.