The University of Science and Technology of China has developed an acrylic resin material that can quantitatively detect gamma radiation dose

Gamma rays, also known as gamma particle streams, are high-energy electromagnetic waves with a wavelength shorter than one thousandth of a nanometer.

Recently, the team of Professor Zhang Guoqing of the National Research Center for Microscale Material Science of the University of Science and Technology of China discovered that polymethyl methacrylate (English abbreviation PMMA, a kind of acrylic resin) or polyvinyl chloride (English abbreviation PVC, often used as a plastic pipe for sewers) This kind of engineering plastics can quantitatively release acidic substances in the acrylic film under the radiation of gamma rays

The sensor is essentially a blue fluorescent molecule that is sensitive to acid and alkali but is stable under irradiation conditions (for example, the well-known hydroxychloroquine is also a quinoline molecule) blue fluorescent molecule, which is embedded in acrylic In the resin film, with the increase of the γ-ray radiation dose, the blue luminescence intensity of the film gradually weakens, and the red luminescence gradually increases.

Figure 1: Schematic diagram of PMMA acrylic resin or PVC resin sensor producing protons and fluorescence changes of quinoline derivatives under γ-ray radiation

In order to verify the mechanism of γ-ray irradiation to release acidic substances, the research team added a small amount of acid in the process of preparing the film to cause the same effect as receiving high-dose γ-ray radiation

Figure 2: (a) After different doses of γ-ray radiation, PMMA film embeds fluorescent molecules, the luminescence of the UV lamp at 365 nm (unit: Gy); (b) After different doses of γ-ray radiation, the package Fluorescence spectrum of PMMA film embedded with fluorescent molecules; (c) In a larger dose range, the ratio of the emission peak red zone I ₅₈₅ to blue zone I ₄₆₈ is linear with the radiation dose; (d) Under different cycle times, Fluorescence spectrum of PMMA film embedded with fluorescent molecules; (e) In the cycle experiment, the change of the maximum fluorescence emission peak of PMMA film with embedded fluorescent molecules

This technology can be mass-produced at low cost and has broad application prospects