AFM System Helps Researchers to Study the Interaction of Bacteria with Microstructured Surfaces

Dr Christine Müller-Renno is a member of the Ziegler Group in the Physics Department at the University of Kaiserslautern in Germany. The main topics of their research are in nano- and microelectronics, as well as in medical engineering and fluid analysis. Other topics include catalysts and stain-resistant coatings by the use of nanomaterials.

The Group uses the JPK NanoWizard® AFM to study the interaction of bacteria with microstructured surfaces. They look at micromilled titanium surfaces. They study the adhesion of single bacteria to the surface and investigate the elastic properties of the bacteria adhered to the surface (for example, as a function of pH). The goal of all these measurements is to find the best surface structure bacteria combination to produce a biofilm reactor. The NanoWizard is also used for single molecule force spectroscopy. They measure the adhesion of single protein molecules to different surfaces with the goal to compare the results with simulation experiments dealing with protein adhesion (molecular modeling).

AFM is used because of its all-round flexibility –for biology and surfaces under various conditions, e.g. fluids, air, etc. AFM provides an insight into the interaction directly at the surface (e.g. protein with the surface) with very high resolution. It also enables the simultaneous measurement of elastic properties with the imaging of the sample.

The group use a variety of AFMs along with light and scanning electron microscopes. Asked about the merits of using the NanoWizard®, Dr Müller-Renno said: “The benefit for us is the very, very good combination of light microscopy and AFM (also for opaque samples - most of our samples are opaque). In addition, the instrument gives all the requirements we need for our biology studies.”