Return to search

The development of novel electroanalytical interfaces for point of care diagnostics

Reduced sulphydryl thiols (RSH): cysteine, homocysteine and glutathione are fundamental cellular components having important biological functions, including roles within the pathogenesis of a variety of clinical conditions. Independent analysis of these species is problematic and analytical difficulties relating to instrumental selectivity and sensitivity need to be overcome. This thesis describes the work carried out on the development and characterisation of a range of systems that could be used to facilitate thiol detection, ideally at the point-of-care, focussing largely on electrochemical techniques. Silver-thiol interactions were studied as a route to assist the sample processing. Here a novel controlled silver release mechanism was assessed. Silver release was found to be dependent upon the thiol structure. This has possible future applications to the development of methods to prevent biofilm formation, although the full mechanism of silver-thiol release requires further understanding. The development of unique molecular imprinted polymers was attempted. These would facilitate the detection of amino acids and the relevant thiol species via the amine functionality. The polymers proved unstable in the presence of hydroxylamine. However, this property makes the polymers suitable for use as protective or sacrificial polymers which can potentially be exploited in the manufacture of patterned electrodes. The nucleophilic substitution reaction between thiols and quinones, or quinone type materials, was explored as a possible route to assist selective thiol detection via electrochemical or colorimetric methods. Development of such reagentless sensing platforms would be beneficial in clinical analysis. Selectivity of thiol determination was achieved, although sensitivity issues will restrict real-world applications. A pH sensor utilising uric acid redox sensitivity was developed and was integrated within a disposable electrode assembly to enable wound pH monitoring. This platform was adapted as a prototype generic sensor for thiol analysis.

Identiferoai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:629257
Date January 2012
CreatorsNewton, L. A. A.
PublisherNottingham Trent University
Source SetsEthos UK
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Sourcehttp://irep.ntu.ac.uk/id/eprint/355/

Page generated in 0.0013 seconds