Originally published at www.ipm.fraunhofer.de/en/press-publications/press-releases.htmlAt the Department of Molecular Plant Physiology, Faculty of Biology, at the University of Freiburg, Professor Andreas Hiltbrunner's research group is investigating how plants can perceive light. An important aspect of this is the study of light-sensitive plant proteins - so-called phytochromes. Thanks to a measuring instrument specially tailored for this purpose by the CIBSS partner institution Fraunhofer IPM, the researchers can now investigate the processes that take place in phytochromes at the molecular level as a result of light exposure in much greater detail and with much greater precision than before: Ratiospect 2.0 from Fraunhofer IPM is an optical absorption spectrometer that is unique in the world - highly accurate and easy to operate.


Tracking the plant sundial
How can plants perceive light? A research team led by CIBSS researcher and plant physiologist Prof. Dr. Andreas Hiltbrunner is investigating this question using technology by Fraunhofer IPM – a regional partner of CIBSS.

The Ratiospect 2.0 measuring system allows much faster, more accurate and more sensitive content determination of light-sensitive plant proteins than before.
Well-connected in Freiburg: University, Fraunhofer IPM and industry
Phytochromes can be detected in plant samples based on their reaction when exposed to light. "This can be done with the help of highly sensitive optical absorption measurements," says Freiburg plant physiologist Professor Hiltbrunner. "Unfortunately, however, there are no ready-made standard measurement systems for this on the market that are suitable for use in our laboratories. Therefore, we were looking for a supplier who could develop and build such a measuring device according to our requirements." Dr. Sebastian Wolf, project manager at Fraunhofer IPM, was immediately enthusiastic: "The task was both exciting and concrete. And we were very confident that we would be able to develop a measuring system that could meet the desired requirements." In collaboration with Dr. Cornelia Klose, who led the Ratiospect 2.0 project in Professor Hiltbrunner's research group, and the Freiburg-based company PSE AG, Fraunhofer IPM then developed the measuring device. It allows a much faster, more accurate and more sensitive measurement of phytochrome content than before
Highly sensitive absorbance measurements thanks to Ratiospect 2.0
Ratiospect 2.0 switches phytochrome molecules by laser exposure and measures the resulting characteristic transmittance changes with very high precision. The measurement system can measure transmission changes from 100 % to 99.999 % as well as from 1.0 % to 1.0001 % - in just a few seconds. As a result, Professor Hiltbrunner's research group is now able to determine concentrations that it was previously unable to resolve. At the same time, the researchers can now carry out test series even faster than before: Ratiospect 2.0 can handle plant samples independently, measure them automatically, and process and manage the measurement data obtained. These features make Ratiospect 2.0 an indispensable laboratory instrument for a project within the Cluster of Excellence CIBSS – Centre for Integrative Biological Signalling Studies of which Professor Hiltbrunner is a Member and the Frauenhofer IPM is a regional partner.