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This thesis discusses and demonstrates the utility and advantages of redox catalytic reactions and small scale synthetic applications. In particular electro-catalytic reactions are investigated along with electrogenerated chemiluminescence (ECL). ECL is used both as a probe for investigating the redox reactions and as an analytical method. The first chapter reviews the current techniques and achievements found in the area of dynamic electrochemistry and electrogenerated chemiluminescence and discusses occurrence, mechanism and potentially useful reactions worthy of further investigation for analytical applications. In Chapter 3 the electrocatalytic ECL reaction of Ru(bpy)32+ with tertiary amines in particular with codeine as a model compound was investigated. The aim of the work was to develop a portable drug testing device, that gave good sensitivity and reproducibility. The Ru(bpy)32+ was immobilized within the sol-gel matrix to develop a sensor which could be used directly for measuring tertiary amine containing drugs in buffer solution without the need to add reagents. A system of three electrodes was used in which Ru(bpy)32+ was immobilised on to a glassy carbon working electrode. Initial work involved physical entrapment of the Ru(bpy)32+ within the sol-gel matrix however, problems occurred with leaching of the reagent from this matrix. This problem was overcome by the covalent attachment of a novel Ru(bpy)32+ derivative to the sol-gel matrix. Using this approach a calibration was obtained using ECL for the determination of codeine over the range 1E-3 to 1E-7 M in aqueous buffer with a limit of detection of 2.65E-6 M for codeine. Covalent attachment, as compared to the physical entrapment of CL reagent, was advantageous as it ensured homogeneous distribution of the reagent within the matrix and prevented leaching. This reduced analysis costs, extended sensor lifetime and gave a reproducible analyte responses. This method was, however, only suitable for drugs that were soluble in aqueous solution and an alternative approach was needed for insoluble compounds. Chapter 4 describes an alternative approach for ECL reaction of tris(2,2’-bipyridyl)ruthenium(II) with tertiary amine compounds. In this approach the electrode was modified using microdroplets of a highly hydrophobic tertiary amine (trioctyamine). As well as allowing for the analysis of compounds that were insoluble in aqueous solution, this setup allowed the investigation of the electron transfer reaction occurring on liquid|liquid interfaces. This mechanism was studied in fully protonated and deprotonated conditions. The extent of the electrochemiluminescence production was shown to be dependent on the degree of the interfacial protonation. Moreover, the data obtained enabled the estimation of the biphasic pKa, which was found to be approximately 10.8. Furthermore, the mechanism was studied in fully deuterated and dedeuterated conditions, in order to investigate the effect of the deuterium on the biphasic pKa. Results suggest that the pKa increases to 13.18 when deuterium is used instead of protons. In Chapter 5 a further electrocatalytic reaction was investigated. The reaction was that of vitamin B12a with trans 1,2-dibromocyclohexane (DBCH) in a homogeneous dimethylformamide media. The reaction was studied by cyclic voltammetry. Four peaks were seen due to the two chemically reversible redox (two electron process) couples for vitamin B12a/B12r (Co(III)/CO(II)L) and B12r/B12s (Co(II)L/Co(I)). When the bulk electrocatalytic reaction was tried in a “one pot” system, the reduction could not, however, be achieved; the cathodically synthesised Co(I)L was thought to be reoxidised at the anode. A “two pot” system did not have sufficient potential control and, therefore, chemical reduction was investigated instead. Four reducing agents (Na/amalgam, NaBH4/NaOH, DL-cysteine/alkali solution and Zn dust/NH4CL) were studied to reduce B12 to B12s for a simple biphasic batch reaction of vitamin B12s with DBCH. The mild reducing agent Na/amalgam was not successful but the other three methods were shown to give 100% yield if the reaction vials were rigorously shaken. This simple type of green, surfactant free reaction has not been previously reported. The reaction was then investigated in a microfluidic system. For this work the vitamin B12 was reduced before being introduced into the microfluidic device. NaBH4/NaOH and DL-cysteine/alkali solution were selected as the most compatible reducing agents for the microfluidic device. Two types of microfluidic device were employed, one with a T-shape channel, and one with a serpentine channel. The conversions obtained with the microfluidic device were much lower (approximately 10%) than for the simple batch reactions (100%). The yield increased as the flow rate decreased, and the residence time increased. Using the serpentine channel made no noticeable difference to the conversion rate. Problems were also seen due to the use of excess reducing agent prior to introduction of the reduced vitamin B12 into the microfluidic device, as this could cause blockages and bubbles. The main problem was, however, the lack of mixing in the device. One way to overcome this would be to use an ultrasonic transducer with the microfluidic device but although preliminary experiments were carried out, there was not time to fully investigate this approach.

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Glass is one of several early modern industries where the development from small-scale workshop to large-scale industry offers a valuable insight into wider socio-economic trends. Previously, medieval and early modern forest (wood ash) glass has been studied using a range of analytical techniques. However, characterisations of production centres and exchange systems for forest glasses are difficult to verify, in part because very few examples of raw glass from furnace sites have been investigated. The necessity for an independent means of provenancing glass used in the study of exchange systems is clear. Compositional analysis can provide evidence for the raw materials used and can sometimes provide compositional groupings specific to sites. However, strontium, neodymium and oxygen isotope determinations can actually provenance the glass by linking the geological ages, or sources, of raw materials to production sites. The potential of using Sr and O isotopes in the study of plant ash glasses has recently been established (Henderson et al., J. Archaeol. Sci., 32, 2005). Using EPMA-WDS over 179 raw glass samples from 12 English production sites in operation between the 14th and 17th centuries have been analysed. These analyses have shown compositional types which are relatable to the region or, in some cases, the period of production. Over 60 archaeological glass, raw material and model glass samples from these sites have also been analysed using mass spectrometry to determine strontium, neodymium and oxygen isotope ratios. The isotopic analyses have also been very effective in showing differences between sites, even those within the same region. This thesis will argue that the combination of these techniques offers a promising new way of provenancing archaeological glass and provide an insight into the organisation of production at this time.

Novel and sensitive CE methods coupled with LIF and LINF detection using a series of separation modes have been developed for profiling organic metabolites containing amines and carbohydrates in mammalian and plant biofluids. In this study, metabolites containing an amine group were derivatized with 4-Fluoro-7-nitro- benzofurazan (NBD-F), separated by micellar electrokinetic chromatography (MEKC), and detected by argon-ion (488 nm) laser-induced fluorescence detection (LIF). Under the optimized conditions most of the amine-containing metabolites in human biofluids such as plasma, urine and saliva could be identified by reference to standard compounds and the concentrations measured were found to be in agreement with literature values. Furthermore, 17 carbohydrates including mono-, di- and oligosaccharides are also simultaneously derivatized via a two-step reaction involving reductive amination with ammonia followed by condensation with NBD-F. Under the optimized derivatization conditions all carbohydrates were successfully derivatized within 2.5 h and separated within 15 min using borate buffer (90 mmol L−1, pH 9.2). The method was applied to measure sugars in nanoliter volume samples of phloem sap obtained by stylectomy from wheat and to honeydew samples obtained from aphids feeding from wheat and willow. Finally, an on-line sample concentration technique, sweeping-micellar electrokinetic chromatography (sweeping-MEKC), in conjunction with UV laser-induced native fluorescence detection (LINF) was developed and applied to the detection of native fluorescent analytes in biofluid samples such as plant phloem sap, human plasma and urine samples. The concentration limits of detection of analytes were in the range 7–100 nmol L−1, which were 250–3600-fold improvement for dopamine, DOPA and epinephrine compared with conventional capillary zone electrophoresis (CZE). The results indicated that a long-term limitation of relatively low detection sensitivity in CE-UV analysis arisen from the small injection volume and short optical path-length could be much improved, while no apparent loss in separation efficiency occurred.

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