UT desalination chip should increase efficiency of medicine development

Susan Roelofs, researcher with the UT research institutes MESA+ and MIRA, has developed a chip that should support the faster and cheaper marketing of new medicines. Her chip should make sure that the pharmaceutical industry can improve the analysis preparation of solutions containing candicate compounds for potential medicine. The chip removes the salt from the solution so that the solution can be analyzed. By scaling down an existing desalination technique to a chip it should be possible to strongly reduce the necessary amount of liquid containing the (expensive) potential medicine compounds. Roelofs will be awarded a doctorate for this research on 30 September at the University of Twente. Next she will research in a technical and financial feasibility research what possibilities there are to market the desalination chip.

The pharmaceutical industry wants to analyze the largest amount of candidate compounds for medicines as possible as quick as they can. A much used method for this is called mass spectrometry which separates molecules based on weight and charge. However, to properly analyse a sample using a mass spectrometer, the majority of the present salt has to be removed from the solution.

A disadvantage of the methods currently in use is that you need relatively large samples and that it takes quite long to desalinate them. In her doctoral research, Roelofs has developed a chip which, by using an already existing desalination technique, can desalinate the samples, but it needs much smaller samples and can speed up the process significantly. In stead of taking samples of 1 to 10 microlitres, the chip can use volumes of nanoliters or even picolitres. A picolitre is a thousand times smaller than a nanolitre and a nanolitre is a thousand times smaller than a microliter.


The chip contains two electrodes on which a voltage will be applied. The electrodes attract the charged salt particles which reduces the salt concentration in the bulk of the liquid. By using her chip, Roelofs managed to remove 26% of the salt from the solution during the research but according to the researcher herself there is a lot more room for improvement. “Our research’s main goal was to prove that the system works. And in that we have succeeded.” By adapting the chip’s geometry, Roelofs expects the desalination percentage to be raised up to 60% to 90% depending on, amongst others, the required speed.


Roelofs and her advisers recently received a take-off grant of €40,000 from the Technology Foundation STW. With this grant, Roelofs will begin a technical and financial feasibility research into commercializing the desalination chip later this year. In addition, Roelofs plans to set up her own company that will market the chip.


Roelofs carried out her doctoral research in the department BIOS Lab-on-a-Chip. Mathieu Odijk and Albert van den Berg guided her along the way. During her research, she collaborated with researchers from the Eindhoven University of Technology and the Massachusetts Institute of Technology (MIT). In 2003 Roelofs was awarded the Marina van Damme scholarship. This €9,000 scholarship is awarded to a successful female UT graduate once a year and is meant to further her career. Roelofs has used her scholarship to carry out a part of her research at the prestigious MIT among other things. Roelofs will defend her doctoral thesis in lecture theatre 4 in the Waaier building on the University of Twente campus at 14:45 hours.