Element Specific Smart Media for Fast, Low Cost Radionuclide Analyses
Lead Research Organisation:
Cardiff University
Department Name: Chemistry
Abstract
Radioactive analyses are currently very challenging for mixtures and/or unknowns. Lowered analysis time, and therefore cost, of radioactive samples is extremely important, as demonstrated by Fukushima effluent sampling. A step-change technological advance in this area of analysis is urgently required. The technological quality of a system applicable to a suite of radioactive analytes has major relevance since these are key radionuclide targets for power plants entering decommissioning.
Our aim is to develop a fast and low cost approach to analysing low level waste (LLW) samples containing a mixture of radionuclide contaminants and exploiting existing scintillation counting infrastructure. We will develop novel scintillants that selectively target radionuclides in a mobile LLW aqueous phase. The approach will require minimal work-up and manipulation of aqueous LLW, and dramatically reduce the volumes of organic solvent typically used in commercial scintillant cocktails, thus reducing the cost and time of analysis, and overall environmental impact. This methodology will also allow parallel, rapid analyses of different radionuclide targets by using a mixture of different scintillant beads for each targeted analyte.
The benefit of faster analyses for the wider suite of radionuclides could therefore be realised not only in the area of nuclear remediation, but also in accident scenarios, contingency, resilience and homeland security. The project has arisen from an unmet and urgent need within the (global) nuclear industry for rapid and selective analyses, thus creating the pathway to impact through our immediate partnership with NDA, NNL and our wider engagement with the international nuclear industry and its stakeholders.
Our aim is to develop a fast and low cost approach to analysing low level waste (LLW) samples containing a mixture of radionuclide contaminants and exploiting existing scintillation counting infrastructure. We will develop novel scintillants that selectively target radionuclides in a mobile LLW aqueous phase. The approach will require minimal work-up and manipulation of aqueous LLW, and dramatically reduce the volumes of organic solvent typically used in commercial scintillant cocktails, thus reducing the cost and time of analysis, and overall environmental impact. This methodology will also allow parallel, rapid analyses of different radionuclide targets by using a mixture of different scintillant beads for each targeted analyte.
The benefit of faster analyses for the wider suite of radionuclides could therefore be realised not only in the area of nuclear remediation, but also in accident scenarios, contingency, resilience and homeland security. The project has arisen from an unmet and urgent need within the (global) nuclear industry for rapid and selective analyses, thus creating the pathway to impact through our immediate partnership with NDA, NNL and our wider engagement with the international nuclear industry and its stakeholders.
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/N509449/1 | 01/10/2016 | 30/09/2021 | |||
| 1905588 | Studentship | EP/N509449/1 | 01/07/2017 | 31/03/2021 | Danielle Merrikin |
| Description | Radioactive analyses is currently challenging for mixed radionuclide samples, such as those found in low-level waste in the nuclear industry, and relies on toxic and environmentally unfriendly organic solvents. In addition, samples are typically aqueous phase and therefore the work-up can be time-consuming. This not only has a large negative impact on the environment, but also increases disposal cost of samples. Therefore, development of low-cost and time efficient analysis of these samples is an urgent need within the nuclear industry, impacting our immediate partnerships with NDA, NNL and wider engagement with the international nuclear industry and its stakeholders. During the PhD award, a low-cost approach inspired by the scintillation proximity assay has been developed. Scintillant nanoparticles decorated with specific receptors on their surface can be dispersed in an aqueous medium. Radioisotopes present within the sample can bind selectively to the nanoparticle surface, leading to emission of light following interaction between the released beta-particle of the radionuclide and the scintillant inside the particle. A range of novel scintillants have been developed and encapsulated within water-dispersible nanoparticles, leading to minimal work-up and manipulation of aqueous LLW, and therefore no longer requiring organic solvents typically used in commercial scintillant cocktails for liquid scintillation counting. This therefore reduces the cost and time of analysis, and overall environmental impact. Surface functionalisation of the particles has been achieved, giving enhanced selectivity, and this will lead on to the development of parallel analyses of different radionuclide targets. During the award I have attended yearly conferences organised via the NDA PhD Bursary Scheme, in which I was awarded Best Poster and Best Presentation in 2018 and 2020 respectively. I have also been on secondment to the National Physical Laboratory (NPL), where I helped test the novel scintillants in the presence of radionuclides typically found in low level waste. NPL have since analysed consequent samples as the work has progressed. To successfully analyse each step in the development of the novel scintillant particles, skills relating to nanoparticle morphology have been developed, including the use of Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX). Microwave Plasma-Atomic Emission Spectrometer (MP-AES) has also been used for the analysis of trace metals, and UV-vis and luminescence spectroscopy has been used extensively in the analysis of both the photophysical properties of the novel scintilants and energy transfer mechanisms within the particles, which is fundamental for the scintillation pathway. Electron paramagnetic resonance (EPR) spectroscopy has also been utilised to probe the internal particle structure to better understand these transfer mechanisms. |
| Exploitation Route | Results have shown that the developed particles successfully scintillate in the presence of a range of radionuclides, with proof-of-concept studies showing the capability of selective analysis. Therefore, these systems can be further taken forward either in an academic (further PhD studentships) or industrial (via NDA/NNL) setting to further develop selectivity, for the use in their primary purpose, that of the analysis of low-level waste in a green and low-cost manner. |
| Sectors | Chemicals,Energy,Environment |
| Description | NDA PhD Bursary Scheme |
| Organisation | Nuclear Decommissioning Authority NDA |
| Country | United Kingdom |
| Sector | Public |
| PI Contribution | Undertook research to complete the aims set out by NDA and PhD supervisors throughout the scheme, towards the fulfillment of the PhD degree. |
| Collaborator Contribution | Financial contribution has been made throughout the programme, as well as support from an industrial supervisor, yearly NDA site visits and conferences to expand knowledge. |
| Impact | NDA PhD Conference Best Poster Prize - 2018 NDA PhD Conference Best Presentation Prize - 2020 Results obtained during PhD will lead directly to future work and manuscripts. |
| Start Year | 2017 |
| Description | Testing of Novel Scintillants at the National Physical Laboratory |
| Organisation | National Physical Laboratory |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | Provided samples for testing that were relevant to their research interest. |
| Collaborator Contribution | Provided Radionuclides to test scintillation capabilities of samples, and provided both infrastructure and personnel to run samples and analyse results. |
| Impact | Results from this collaboration have fed directly into PhD research and progression with the project, and will lead to future manuscripts. |
| Start Year | 2019 |