Precise X-ray Visualization by Double Network Polymeric Gel

Gel dosimeters are an important tool for radiotherapy dose verification due to their tissue equivalence, but their widespread use has been constrained by complex readout processes, limited spatial resolution, and instability of postirradiation. Herein, we use radiation-induced expansion, yielding a dose-dependent and continuous redshift in its structural color. This double network dosimeter can detect X-rays with a maximum sensitivity of 35.8 nm/Gy and spatial resolution exceeding 50 μm in the range of 0-10 Gy. Moreover, it exhibits excellent stability against environmental factors, including UV irradiation, and its dosimetric information (spectral reflection peak position) remains unchanged after 10 drying-wetting cycles. In addition, it is feasible for three-dimensional (3D) printing of complex shapes, a capability that is inaccessible to existing gel dosimeters. Therefore, the present study provides spatially precise gel dosimeters for advanced radiotherapy verification.