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This work centres upon the creation of a portable means of neutron spectrometry, after concern had been raised for the safety of both human beings and electrical components on¬board aircraft, due to the increased levels of cosmic radiation exposure, whilst at flight altitude. The work follows on from that previously reported by Dr. S.D. Monk, wherein a device was constructed, which had limited neutron characterisation capabilities and was hampered by reliability issues. The new, novel instrument presented in this work, has employed new materials and construction techniques as a means of improving upon areas where the prior instrument fell short. An initial task was to establish a suitable means of detecting thermal neutrons over large surface areas. In order to fulfil this requirement, a series of small scale, thin film surface barrier detectors were constructed and tested against a variety of characterised neutron sources. Dimensional information from the most favourable of the sample detectors was then used to inform a set of Monte Carlo based computer simulations. The purpose of these simulations was to deduce a set of potential geometries for a series of coherent moderators that could, once fabricated along with the recreation of surface barrier detectors upon their surfaces, offer the ability to resolve a spectrum of different neutron energies. Discussion is made with regards to the resultant data captured from each device in real world test environments and also looks at the merits of the prototype instrument created. A list of recommendations is made with respect to any future work in this area. Finally, this work has contributed to the generation of four separate, peer reviewed journal papers. These papers describe the work undertaken, both for the construction/testing and also that of the simulation work. Because of the device's commercial potential and its uniqueness, a patent application has been submitted.

The profiling of hormones is an important requirement in sports dope testing and it is increasingly being used for clinical applications. The screening of samples for the detection of steroids is usually undertaken in urine and these analyses present many challenges. Issues related to the complexity of the matrix, the separation of exogenous from endogenous species and the very low detection limits have placed increasing demands on clinical and International Olympic Commission accredited laboratories. Whilst liquid chromatography (LC) systems provide a highly sensitive detection method for targeted species, gas chromatography, especially when coupled to mass spectrometry, is considered preferable for the screening of a wider range of target and unknown species. Existing chromatography methods are not without their limitations, not least the difficulty in reproducibly derivatising the wide range of steroids that can be exogenously administered, in particular the so called ‘designer steroids’ which deliberately hinder this process. Initially, a pilot study was conducted to investigate whether aptamer-coated magnetic beads could provide a simple, low cost method for the extraction of estradiol from urine, prior to its detection and quantification with mass spectrometry. In reality, the process necessitated the use of additional solvent extraction steps to the standard method applied previously. These additional steps added complexity and were not without issue and the limit of detection was not found to be adequate for the proposed clinical purpose. The project explored the application of comprehensive gas chromatography/mass spectrometry (GC x GC/MS) coupled to bespoke molecular imprinted polymers (MIPS) as an alternative solution to the problem of the screening of multiple steroids in urine. Twelve structurally similar and commercially relevant steroids were used to develop the chromatographic method. Once optimised, these compounds were then extracted from synthetic urine using a MIP templated with testosterone and developed during the project. Significant improvements compared to commercially available C-18 materials were found. All the steroids were identified and detected when spiked at the 10 ng/ml level, as required by World Anti-Doping Agency (WADA) at the time. The method was further validated and then successfully applied to the extraction of designer steroids from synthetic urine, in the presence of the original steroids. Epistane, which has a different structure to testosterone, was not detected indicating the efficacy of the templating process.

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The fluorescence interaction of lanthanide ions with a number of amino acids, peptides and proteins has been investigated. Only Tb(III) fluorescence was enhanced by the substances tested. Tb(III) fluorescence was enhanced by tyrosine and peptides containing both tyrosine and tryptophan but not by tryptophan alone. The enhancement by tyrosine and the class A protein ribonuclease A was attributed to a collisional interaction, not binding at specific sites. Many class B proteins were shown to enhance Tb(III) fluorescence but the effect was not necessarily associated with vacant metal sites. A detailed study of the fluorescence interaction of Tb(III) with con A and porcine trypsin was made. None of the systems tested gave the huge Tb(III) fluorescence enhancement at small metal:protein ratio shown by transferrin and conalbumin. The interaction in these latter proteins involved rare earth binding at the Fe(III) sites. The interaction in the other class B proteins was probably due to a very complex interaction, possibly involving binding at a number of different sites and collisional interaction.