Quantum Sensing in Radiobiology: An NV Center Approach to the FLASH Effect

Radiotherapy (RT) is a cornerstone of cancer treatment, but its effectiveness is often limited by damage to healthy tissues, leading to severe side effects. FLASH radiotherapy (FLASH-RT) - using dose rates exceeding 50 Gy/s - has shown remarkable promise in sparing normal tissues while effectively controlling tumors. However, the mechanisms underlying the FLASH effect remain poorly understood, hindering its clinical translation. A major obstacle lies in the limitations of current detection methods, which rely on endpoint measurements and invasive chemical assays, preventing real-time observation of the dynamic processes triggered by radiation.

To tackle this challenge, we have developed a combined FLASH-capable electron linear accelerator and NV quantum microscope, enabling in situ, real-time detection of high-energy radiation–induced physicochemical and biological processes at the nanoscale. By systematically studying the effects of various radiation conditions, we aim to uncover the fundamental mechanisms of radiotherapy using NV quantum sensing, particularly the origins of the tissue-sparing effects in FLASH-RT.

In this talk, I will present the first results from this platform, including real-time measurements of temperature changes, reactive oxygen species (ROS) production, and lipid peroxidation in biomimetic samples exposed to FLASH radiation.