A device for in vitro irradiation with alpha-particles using an alpha-emitting radioactive source

Area of Science:

• Radiobiology
• Cellular and Molecular Biology
• Radiation Oncology

Background:

• Investigating the relative biological effectiveness (RBE) of alpha-particles is crucial for understanding radiation-induced cellular damage.
• Accurate dosimetry and controlled irradiation conditions are essential for reliable RBE studies.
• Existing methods for alpha-particle irradiation may be limited by accessibility and machine time.

Purpose of the Study:

• To design and validate a user-friendly device for irradiating cultured cells with alpha-particles.
• To enable the investigation of alpha-particle RBE in cell killing, chromosome aberrations, mutagenic changes, and transformation.
• To provide a cost-effective and accessible tool for radiobiology research in common laboratory settings.

Main Methods:

• Development of a laboratory device utilizing an Americium-241 alpha-source (33.4 MBq).
• Characterization of alpha-particle energy (3.20 MeV), incident angle (82.8 degrees), and fluence rate (4.7 x 10^5 cm^-2.min^-1).
• Maintenance of optimal cell culture conditions (temperature, CO2) during irradiation, with an average LETinf of 138 keV/micron and dose rate of 0.10 Gy/min for a 5-micron cell layer.

Main Results:

• The device successfully irradiates a monolayer of cultured cells with controlled alpha-particle parameters.
• Key irradiation characteristics, including energy, angle, fluence rate, LETinf, and dose rate, were quantified.
• The system ensures a conducive environment for cell cultivation during the irradiation process.

Conclusions:

• A novel, accessible device for alpha-particle irradiation of cultured cells has been developed.
• This tool facilitates the study of alpha-particle RBE and associated biological effects.
• The device offers a practical solution for researchers without requiring specialized facilities or extensive machine time.