Department of Physical Biology and Advanced Light Microscopy

Stelzer flyer

How does the development of organisms unfold, and how can we observe this meticulously and with sufficient clarity? Since the 1980s scientists have been using confocal fluorescence microscopy for the precise analysis of cell formation. In this process, molecules within cells are stained with a fluorescent substance and induced to fluoresce under an optical microscope. Changes in their three-dimensional arrangement can then be recorded with cameras as a function of time.

Professor Ernst H. K. Stelzer has been involved in the development of high-resolution fluorescence microscopy for more than twenty years. He has also contributed significantly to optical levitation, optical tweezing and laser cutting of biological materials, which allow very precise investigations. In the past; the energy of the photons destroyed the cells to a large extent, whereas the use of a modern fluorescence microscope leaves even delicate fish embryos almost completely unharmed. The key is the use of micrometre-thick beams of light that illuminate only the tiny part of the cell under investigation. In addition, the microscope records images of the sample from several directions and angles. Using these complex sets of individual images, computers generate films, as well as three-dimensional, overall images. "This microscopic method creates new opportunities for capturing both molecular dynamics and the long-term development of biological model organisms or sub-cellular structures", reports Stelzer. "We investigate the cells under the most natural growth conditions possible, which allow us to obtain very precise results". The effects of environmental changes or genetic mutations can also be measured and directly compared. Stelzer and his team conduct research on the embryonic development of zebrafish, Medaka fish and the differences between clones of the fruit fly Drosophila. One of Stelzer's objectives is to contribute to a more accurate development of pharmaceutical drugs by recording the exact biophysical parameters.

As a teacher, Stelzer desires to motivate his students to always consider scientific procedures and results critically. In addition to the range of possible methods of microscopic work, he demonstrates the potential research uses of mathematical and analytical computer programmes such as "Mathematica". 

Brief Biography

Stelzer klein

Ernst H. K. Stelzer wrote his Diploma (master's) thesis at the Max Planck Institute for Biophysics and received his degree in physics from the Goethe University Frankfurt. In 1987 Heidelberg University awarded him a doctorate in physics for his thesis on confocal fluorescence microscopy, a type of microscopy that allows three-dimensional observation of objects. He subsequently worked as a group leader at the European Molecular Biology Laboratory (EMBL) in Heidelberg, doing research in various departments in the fields of cell biology, developmental biology and cell biophysics. In 2009 Stelzer was appointed professor at the Goethe University Frankfurt. His newly-created professorship is part of the "Macromolecular Complexes" Cluster of Excellence at the Goethe University.


Prof. Dr. Ernst H. K. Stelzer
Institute of Cell Biology and Neuroscience
Max-von-Laue-Str. 15 (FMLS-Gebäude)
60438 Frankfurt am Main
Telephone: +49 (0)69 798 42547