The Medical Radiation Biophysics Department at iThemba LABS is a pioneering research division dedicated to understanding the biological effects of radiation on living systems, with a special focus on particle therapy and radiation protection. Drawing on a unique convergence of expertise in radiation biology, medical physics, and applied mathematics, the department leverages cutting-edge proton and neutron beam technologies to explore radiation interactions at multiple energy levels. With a robust infrastructure and a history of innovation, the department plays a critical role in advancing research, from developing novel radiopharmaceuticals to contributing to global radiation safety protocols. The department is committed to fostering international collaborations, offering advanced training for the next generation of scientists, and driving impactful research that supports both medical therapies and public health initiatives worldwide.
Advancing Radiation Research: Precision, Innovation, and Clinical Impact
The research conducted within the field of medical radiation biophysics at iThemba LABS is a cutting-edge exploration of radiation’s interaction with biological systems. Central to this work is the precise manipulation of proton, neutron, and photon beams, tailored to various energy levels to study their biological effects in detail. These highly controlled radiation fields are key to advancing both therapeutic techniques, such as particle therapy, and enhancing our understanding of radiation safety for clinical and environmental exposure.
A major focus of research is on the biological effectiveness of different radiation types, with particular emphasis on proton and neutron therapy. Investigations into the Bragg curve’s impact in proton therapy provide insights into how biological systems respond at different energy deposition points. This includes studying radiobiological-based treatment planning to refine dose delivery, ensuring that the prescribed treatment focuses not just on the physical dose but the final biological outcome. This approach is poised to revolutionize treatment strategies in particle therapy, ensuring greater precision in targeting tumors while minimizing damage to surrounding healthy tissue.
The development of innovative radiopharmaceuticals is another cornerstone of this work. Through the use of in-vitro cell studies, the uptake of radiolabeled compounds is being explored to enhance early detection and treatment of cancer. Advanced molecular techniques are being used to verify the receptor-mediated uptake of these compounds, with promising results in identifying new markers for both diagnostic and therapeutic applications. Complementing this, in vivo biodistribution studies are performed to analyze the movement and accumulation of these compounds in different tissue types, providing crucial data for preclinical imaging techniques like micro-PET and SPECT.




Radiation Exposure Assessment
Cellular Radiation Response
DNA Damage Mechanisms
Leveraging flexible neutron sources and advanced beam characterization technologies to explore radiation interactions and enhance both cancer therapy and radiation safety.

- Monte Carlo (MC) simulations are computational models used to simulate radiation interactions with biological and physical systems. These models are especially useful when direct measurement is impractical due to complexity or scale.
- In radiation protection, MC simulations are used to model secondary radiation exposure during particle therapy and to assess radiation dose distribution in accident scenarios. They also help in designing new neutron sources and evaluating radiation dose received by workers.
- The department uses MC simulations to complement physical experiments, such as calculating doses delivered to victims of radiation incidents and simulating proton and neutron interactions in radiobiological experiments. This ensures precise dose estimates and better treatment planning for particle therapies.
- Bio-dosimetry involves measuring biological responses to radiation exposure to estimate the dose received by individuals or biological systems. This is particularly important for radiation protection and medical surveillance.
- Bio-dosimetry is used to assess radiation exposure during accidents, radiation therapy treatments, and occupational hazards. The technique helps predict long-term health risks by analyzing changes in biological markers post-exposure.
- The department provides bio-dosimetry services for radiation workers across South Africa and neighboring countries, with recognition by international bodies like the World Health Organization (WHO). The lab is advancing the field by integrating modern molecular methods, such as gene expression analysis, to enhance radiation exposure assessment accuracy.
- Microdosimetry focuses on studying the spatial distribution of energy deposited by radiation at microscopic scales, particularly within individual cells and tissues. This technique is crucial for understanding cellular responses to radiation.
- Microdosimetry is applied in cancer research to study the radiosensitivity of cancer cells and normal tissues, helping to optimize radiation treatments. It also aids in evaluating the effectiveness of radiosensitizers like gold nanoparticles.
- iThemba LABS investigates cancer cell responses to proton and neutron beams, studying how these cells react to radiation with and without the presence of sensitizing agents. These studies aim to enhance cancer therapy by understanding and improving radiation-induced cell damage at microscopic levels.
- In-vitro uptake studies involve exposing isolated cells to radiolabeled compounds to investigate how these compounds are absorbed and interact with biological systems. This technique is vital for the development of radiopharmaceuticals.
- Radiolabeled compounds are tested for their potential in early cancer detection and treatment by observing how effectively they bind to cancer cells. These studies are also used to develop new diagnostic and therapeutic agents.
- The lab conducts in-vitro studies on cancer cells to explore the uptake of radiopharmaceuticals. This research contributes to the identification of promising compounds for nuclear medicine, with the potential to improve both diagnostic imaging and targeted cancer therapies.
- Proton beam therapy uses high-energy protons to precisely target tumors, delivering radiation in a controlled manner with minimal damage to surrounding healthy tissue. Techniques include pencil-beam scanning and passive scattering.
- Pencil-beam scanning allows for highly focused radiation, especially useful in treating small or irregularly shaped tumors. Passive scattering, although less precise, is beneficial for broad-field applications.
- The department is advancing proton beam therapy by studying the biological effectiveness of protons at different points along the Bragg curve. This research aims to develop treatment planning systems based on the biological effects of radiation, rather than just physical dose, improving treatment outcomes in particle therapy.