Development of Practical Ionising Radiation Detectors and Dosimeters based on Quantum Dots

Quantum dots could provide the basis for a method of radiation dosimetry which could be of use in a range of medical and industrial applications. Recent developments in materials science make the reliable manufacture of nanocrystals possible and allow for the variation in the size and composition of manufactured quantum dots. The purpose of this work is to optimise the design of a self-calibrating radiation dosimeter for proposed use in the security and healthcare sectors, with applications which include the determination of received radiation dose by patients and the verification of sterilisation of items such as mail and medical equipment. This will be achieved by investigating the effects of ionising radiation on quantum dots and determining the optimum concentration and size for the detection of electron and gamma irradiation. If successful, this would open the way for the production of a wide range of self-calibrating dosimeters that can be produced in different matrices, which could be read-out optically in real-time and which are amenable to printing onto packaging and other complex surfaces.

The successful design of a self-calibrating dosimeter would not only have an impact on our scientific knowledge and techniques but would also have a positive bearing on the effectiveness of public services in the healthcare and security sectors. It has the potential to open the way for the production of a wide range of self-calibrating dosimeters that can be produced in different matrices, which could be read-out optically in real-time and which are amenable to printing onto packaging and other complex surfaces. The proposed project makes use of UK industry and as such, benefits from commercial applications arising from this work would have an economic impact on UK industry. Exploitation of the potential of quantum dots as scintillators would be of importance to medical imaging, environmental monitoring, security and defense. This would remove restrictions on size which currently exist owing to the reliance on crystal growth, as the quantum dots could be suspended in a transparent matrix which could be of any size desired. Moreover, increased sensitivity would be offered by tuning the size of the quantum dots such that they emit light which can be detected by avalanche photodiodes, rather than by lower quantum efficiency photomultipliers.