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Updated: Jan 9, 2026
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Improving High Viscosity Extrusion of Microcrystals for Time-resolved Serial Femtosecond Crystallography at X-ray Lasers
Published on: February 28, 2019
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Including medium effects and longer temporal scales in TRAX-CHEMxt
Gianmarco Camazzola1,2,3, Daria Boscolo1, Valentino Abram4
1Biophysics Department, GSI Helmholtz Centre for Heavy Ion Research GmbH, Planckstraße 1, 64291 Darmstadt, Germany.
Physics in Medicine and Biology
|December 8, 2025
Summary
This study introduces TRAX-CHEMxt, an upgraded code for radiation biophysical modeling. It simulates chemical effects of radiation in complex biological environments over extended time scales, aiding radiobiological research.
Area of Science:
- Radiation biophysics
- Chemical kinetics
- Computational modeling
Background:
- Radiation biophysical modeling aids understanding of radiobiological processes.
- Accurate simulation of radical species is crucial for radiobiology.
- Current models face limitations in time scales and environmental complexity.
Purpose of the Study:
- To present an upgraded version of the TRAX-CHEMxt code.
- To extend radiation biophysical modeling to longer time domains (up to 1 second) and complex environments.
- To investigate the impact of biomolecules and antioxidants on radiation chemistry.
Main Methods:
- Monte Carlo (MC) chemical track structure algorithms.
- Implementation of TRAX-CHEMxt for computationally lighter simulations.
- Validation against full MC simulations and experimental data.
Main Results:
- The upgraded TRAX-CHEMxt simulates chemical effects up to 1 second in complex media (water, biomolecule RH, antioxidant XSH).
- Code predictions show good agreement with MC counterparts and experimental data.
- Investigated changes in chemical yields based on radiation type, energy, LET, and oxygenation.
Conclusions:
- TRAX-CHEMxt is robust for simulating radiation-induced radicals in complex systems.
- The code enables studies on larger time scales relevant to biological targets.
- Facilitates detailed simulations of specific biological targets under irradiation.
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