Wearable Full-Organic Radiation Detector for Real-Time Dose Monitoring during Radiation Therapy

Mechanical flexibility, portability, low cost of fabrication, scalability onto large areas and human tissue equivalence are crucial properties which make organic and hybrid semiconductors excellent candidates for the development of wearable personal dosimeters. Among others, their employment in the medical field (i.e. during proton therapy treatments) to monitor in real-time and in-situ the dose delivered to the patients during radiotherapy is extremely promising. Here, we present the results achieved with an innovative fully-organic detector, where a flexible phototransistor (OPT) based on dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT) is coupled with a plastic scintillator based on polysiloxane (i.e. homopolymer polymethylphenylsiloxane and polyvinylphenyl-co-phenylmethyl). The ion beam induced luminescence spectra of the scintillators under irradiation with 2 MeV protons and the UV–vis absorbance spectrum of the DNTT film show a significative overlapping, assuring spectral matching between the light emitting sensor (siloxane scintillator) and the photoconverter (DNTT sensitized OPT). Besides, the coupling between the two components of the detector perfectly preserve the mechanical flexibility and conformability of the device. In fact, this detector demonstrated mechanical flexibility down to a curvature radius of RC = 0.5 cm and low power operation (VDS = VGS = 1 V), assessing its potential employment as a personal dosimeter with high comfort and low risk for the patient.