A high-resolution 3D radiochromic hydrogel photonic crystal dosimeter for clinical radiotherapy.

The precise, rapid and direct visualization of 3D topographical dose in the target tissue that is crucial for effective radiation therapy remains a challenge. Herein, by combining hydrogel photonic crystals with film stacking or 3D printing, a 3D radiochromic dosimeter with a dose sensitivity of up to 10 nm Gy ^-1 , a spatial resolution <50 μm, and the ability to detect complex 3D topographical dose distribution was proposed for clinical radiation dose verification. The sensitivity and response range of the dosimeter by radiation-induced polymer cross-linking and consequent Bragg wavelength shift can be tuned via the solid content and extent of acrylate modification. The combination of rapid readout, low dose response, high spatial resolution, and great pre-irradiation and post-irradiation stability highlights the translational potential of this technology for topographical dose mapping in clinical radiotherapy applications.