Tiny Things, Big Ideas
ince the invention of the microscope, scientists have been continuously striving to develop technologies that enable us to explore the micro- and nanocosmos. However, research takes time and is shaped not only by facts, but also by the researchers themselves. We often discuss the results of research, but the motivations behind those who conduct them are rarely explored in detail. Driven by an unrelenting pursuit of innovation, the academic journey of Hanieh Fattahi, head of the Femtosecond Fieldoscopy research group at the Max Planck Institute for the Science of Light, reflects the power of unstoppable curiosity and collaboration in science.
“Life - and especially the academic path - is full of surprises. Over the years, you develop various specific areas of interest in research to which you devote your time and energy,” says Hanieh Fattahi. Most scientists only find their niche over a long period of time: an initial interest grows into a passion and eventually develops into a concrete project through collaboration and networking. During her studies, Hanieh was deeply fascinated by biological microscopy. When the Nobel Prize in Chemistry was awarded to Stefan W. Hell for the development of super-resolution microscopy during her PhD defense, it motivated her to explore the field further. Later, in Professor Xie's research group at Harvard University, she encountered a key challenge in label-free microscopy: achieving super-resolution imaging - microscopes that can visualize tiny structures without dyes or markers. Hanieh realized that she could use the laser technology she had developed at the Max Planck Institute of Quantum Optics (MPQ) to tackle this problem. Today, one of the main focuses of her laboratory is the further development of super-resolution microscopy without labeling.
Dr. Hanieh Fattahi, Dr. Daniel Wehner, Soyeon Jun. Bild: © Susanne Viezens, MPL.
One of the latest research projects by Hanieh's group, carried out in collaboration with Daniel Wehner's team at the Max Planck Institute for Physics and Medicine, has made significant progress: Conditions have been identified under which intense pulsed lasers can be used in living organisms without causing damage.
The collaboration between the two groups was driven by a common scientific question. “My team wanted to find out whether the laser pulses we planned to use would cause damage to biological samples - particularly in terms of their average power, peak power and spectral frequency,” explains Hanieh. At the same time, Dr. Wehner is investigating the remarkable ability of zebrafish to regenerate their central nervous system after injury. To investigate this, he needed a reliable method to damage the zebrafish nervous system in a controlled and reproducible manner. By working together, the two teams found that they could efficiently investigate both scientific objectives in a single series of experiments.
This research shows that physics - contrary to widespread assumptions - is by no means an isolated discipline. “I strongly believe that every scientist is shaped by the network of people they interact with and the tools at their disposal. These interactions and resources guide how we interpret and approach scientific challenges, offering unique perspectives through which to contribute to the advancement of knowledge and the interpretation of the world” Hanieh emphasizes.
Their joint study entitled “Nonlinear dynamics of femtosecond laser interaction with the central nervous system in zebrafish”, which was published last May in Communication Physics, investigates the interaction of femtosecond laser pulses with the central nervous system of zebrafish. Using in vivo measurements, they were able to observe biological reactions in real time. “To evaluate the extent of damage, we examined proteins such as macrophages, which play a crucial role in the healing process,” explains Hanieh. The study shows that damage to the central nervous system of the zebrafish remains limited and controllable when irradiated with femtosecond pulses at 1030 nm and low repetition rates. This means that the method allows longer observation, and more photons can be used without causing damage - as long as the light intensity remains below a safe threshold. These findings are not only valuable for the development of new microscopic techniques with ultrashort laser pulses but are also of great value for Dr. Wehner's research.
Collaboration in research is therefore not only crucial, but also extremely beneficial - even if communication between two teams with completely different areas of expertise can be a challenge. For instance, simple concepts from each discipline need to be thoroughly explained to ensure mutual understanding - like a doctor and a lawyer working together. But this is not necessarily negative. “This interaction turned out to be both highly enjoyable and rewarding. Both sides, including myself, were able to significantly expand our knowledge and understanding through this collaborative effort,” says Hanieh.
Both teams will continue to work together in the next phase to develop a super-resolution microscope. In addition, Hanieh was awarded an ERC Consolidator Grant last September to support her research on label-free detection of neurotransmitters in the new “Beyond the Visible” project. In summary, this collaboration not only provides exciting new insights into how light interacts with living organisms, but also pushes the boundaries of sensor technologies and imaging.
Original publication
Nonlinear dynamics of femtosecond laser interaction with the central nervous system in zebrafish
S. Jun, A.Herbst; K. Scheffter, N. John, Julia Kolb, D. Wehner; H. Fattahi,
Communications Physics 7, 161 (2024)
Welcome to Photonworld – a platform for knowledge, interesting facts and science on the topic of light. Photonworld aims to provide a basic understanding of the physics of light and its countless phenomena. From medicine, to art and physics: all topics are covered.
Photonworld originated as an initiative of the excellence cluster the Munich-Centre for Advanced Photonics (MAP) and the Laboratory for Attosecond Physics (LAP) at the Max Planck Institute of Quantum Optics (MPQ).
The initiator of the project is Prof. Dr. Ferenc Krausz, Chair of Experimental Physics at the LMU and Director of the MPQ.
Photonworld’s Student Zone reports directly out of the PhotonLab, which is supported by the Munich Center for Quantum Science and Technology (MCQST) and the DFG Research Unit FOR 2783. At the PhotonLab, schoolteachers and students can find up-to-date information about experiments and goings-on at the lab, and plan their own visit to the laboratory.
