Cross sections of electron inelastic interactions in DNA

Area of Science:

• Atomic and Molecular Physics
• Biophysics
• Radiation Chemistry

Background:

• Accurate calculation of electron inelastic scattering cross sections is vital for understanding radiation interactions with biological molecules like DNA.
• Existing theoretical models may have limitations, especially for complex organic compounds lacking extensive optical data.

Purpose of the Study:

• To develop and validate a reliable method for calculating electron inelastic interaction cross sections in DNA and its constituents.
• To provide comprehensive cross-section data for DNA bases (guanine, adenine, thymine, cytosine, uracil) and a representative DNA unit.

Main Methods:

• Utilized dielectric response theory and the Penn statistical approximation, incorporating exchange corrections.
• Developed an empirical approach to determine optical energy loss functions for organic compounds.
• Calculated total inelastic cross sections for individual DNA bases and a constructed DNA molecular unit.

Main Results:

• The proposed method demonstrates reliability through comparisons with experimental and theoretical data.
• Calculated cross sections for guanine, adenine, thymine, cytosine, and uracil up to 10 keV.
• Determined cross sections for a DNA molecular unit and its constituents (sugar-phosphate and bases).

Conclusions:

• The developed empirical approach provides accurate electron inelastic cross sections for DNA bases and molecules.
• The calculated data are valuable for dosimetry and modeling radiation effects in biological systems.
• This work enhances the understanding of electron-DNA interactions across various energy ranges.