Compact Neutron Source for Medical Isotope Production

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If you have a heart attack, it's fairly likely that the doctor will inject you with a Technetium-99 tracer. As the tracer circulates through your bloodstream, the Technetium emits X-rays just like an X-ray machine. However, unlike an X-ray machine, the tracer shows up just those regions where there is blood flow, so that blockages can be seen clearly. Technetium is also used in a host of other medical procedures to distinguish other differences in soft tissues: for example, cancer tumours take up certain radiotracers more than normal tissue, so that they 'light up' compared to their surroundings. Technetium is supplied to hospitals by packaging Molybdenum-99 into a generator: Molybdenum-99 decays into Technetium in the generator over about a week, and the Technetium extracted and used for diagnostic procedures. But there's a problem. Right now, large quantities of Molybdenum-99 can only be made in a few specialised nuclear reactors, all of which are becoming too old to be run safely, and recent failures in the two principal reactors have created a crisis in supply, at a time when there is an ever-growing demand. To put it into context, 36 million nuclear medicine procedures were carried out last year, most of which need Technetium. Researchers from the Universities of Manchester and Lancaster are looking at a new method to produce Technetium using a particle accelerator. Using similar technology to that used in particle colliders like the LHC, they propose using a high-power radio-frequency quadrupole (RFQ) to accelerate ions into a target to generate neutrons. Like in the reactors they intend to replace, these neutrons can then be used to make Molybdenum-99. Although an RFQ cannot make as many neutrons as a reactor, it is much cheaper to build and operate, and so many could be built around the country to provide a domestic supply of Molybdenum-99, which the UK doesn't have at the moment despite using over a million doses of Technetium a year. Once the RFQ and target are optimised, researchers plan to build a prototype accelerator to demonstrate the commercial viability of the technique, and are talking to companies already about how to do this.