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The last few decades have seen a dramatic increase in the treatment options for colorectal cancer. These include adjuvant and neoadjuvant chemotherapy and radiotherapy, extended resections, local excision, and deferral of surgery amongst others. These developments are increasing the need for accurate staging of colorectal cancer through imaging; many treatment decisions are now taken before histopathology is available, optimal outcomes are achieved if the first surgical procedure is the definitive procedure, and histopathology results which have determined the need for adjuvant therapy are now frequently affected by neoadjuvant treatment. Assessment of imaging has predominantly judged its accuracy by comparing it to histopathology as a “gold standard”. However, this approach may underestimate the accuracy of imaging due to inaccuracies in histopathological assessment. It may also fail to focus on the adverse risk features which are most reliably identified on imaging. This thesis investigates the role of MRI in improving perioperative staging of both colon and rectal cancer. In a retrospective study of rectal cancer patients undergoing pre-treatment PET/CT and CT, I demonstrated that patients with high-risk features on rectal MRI have an odds ratio of 6 for synchronous metastatic disease compared to those with low-risk features. This suggests that, at least in rectal cancer, MRI is not only accurate when compared to histological staging, but can independently risk stratify patients with systemic disease. The next aim of this thesis was to determine whether it is possible to extend the benefits of local cancer staging with MRI seen in rectal cancer patients to patients with colon cancer. I, therefore, went on to develop a number of MRI sequences in healthy volunteers which allowed good visualisation of the colon. I then applied these to a cohort of colon cancer patients in an attempt to obtain more accurate local staging using 1.5T MRI and 3T than is currently achieved with CT. Overall, I was not able to demonstrate that MRI was significantly more accurate than CT in the local staging of colon cancer, but I was able to obtain a similar accuracy in T staging with 3T MRI (56-76%) to that achieved with CT (66-72%). In the best multiplanar 3T MRI scans, T-staging accuracy was greater than CT (67-79%). In the final part of this thesis, I investigated whether ex-vivo specimen MRI could improve that accuracy of histological staging by helping to select tumour blocks. I hypothesised that part of the “inaccuracy” demonstrated by imaging staging was due to sampling error in the selection of sections for histopathology, and that performing a high-resolution ex-vivo MRI of the specimen might reduce this error by helping to select tumour blocks. I was unable to demonstrate any benefit from this technique.

To explore the feasibility of utilising gallium arsenide bismide (GaAsBi) as a material for use in solar cells, undoped GaAsBi layers ranging from 50 nm to 350 nm in thickness have been grown by molecular beam epitaxy (MBE) in a p-i-n diode configuration. A growth interrupt technique was employed in order to avoid accumulation of excess surface bismuth. X-ray diffraction measurements showed that GaAs1-xBix with x~0.06 can be grown up to at least 100 nm thick with negligible strain relaxation. The GaAsBi layers are highly uniform and free from the common phenomenon of phase separation; however transmission electron diffraction measurements show the presence of CuPt-type ordering. The structures were processed into devices using a combination of photolithography and wet etching. The electrical characteristics of the devices were investigated using current-voltage and capacitance-voltage measurements. The absorption properties of the devices were systematically investigated by measuring the photocurrent both at a fixed wavelength of 1064 nm and over a range of wavelengths. The samples containing GaAsBi layers showed a photoresponse in the near-infrared up to almost 1.3 μm. The absorption coefficients of the layers were obtained from the responsivity data. Below the band gap, the absorption coefficients showed an exponential dependence on the photon energy (Urbach tailing). The electroluminescence properties of the samples were also investigated. All samples showed room-temperature emission from the GaAsBi layers at wavelengths around 1.25 μm. The presence of localized states in the band gap was evident from taking electroluminescence measurements as a function of injection current and temperature.

The ability of three different 'physical' drug delivery systems: liposomes, niosomes and starch microparticles, to increase the efficacy of sodium stibogluconate in clearing L. donovani from the liver of mice have been characterised. The efficacy of free sodium stibogluconate in this model has been used as the standard against which to measure the effectiveness of the drug delivery systems. The two vesicular systems; liposomes and niosomes, gave an approximate ten-fold increase in efficacy compared with the free drug. Modifying the properties of the vesicles by varying their cholesterol content and hence their permeability to the encapsulated drug or varying their surface charge by the inclusion of dicetyl phosphate appeared to have little effect on their efficacy as carriers of sodium stibogluconate. Surprisingly, treatment of infected mice with empty vesicles also led to a small decrease in the parasite load. Testing of the vesicular systems against Leishmania infected peritoneal exudate cells (PECs) in vitro gave results similar to those obtained using the in vivo model in that they increased the efficacy of the sodium stibogluconate. Interestingly, L. m. mexicana and L. donovani were equally susceptible to sodium stibogluconate in vesicles. Whereas L. m. mexicana is relatively unaffected by the free drug as with the in vivo model, empty vesicles had an effect on the parasites in exposed PECs, although this effect was difficult to quantify as there was also considerable toxicity to the PECs. The third drug delivery system tested in vivo, starch microparticles, resulted in a 100-fold increase in efficacy compared with the free drug, thus proving much more potent than either of the vesicular systems. This difference could be due to the mechanism of drug release within the host cell. Nevertheless, all three drug delivery systems tested show potential for the treatment of leishmaniasis. Their use ensures that less drug is required, so overcoming the problems of drug toxicity associated with sodium stibogluconate. The efficacy of tubercidin in combination with inhibitors of nucleoside transport in mammalian cells, nitrobenzoylthioinosine (NBMPR) and dipyridamole, in the treatment of experimental leishmaniasis was investigated both in vitro and in vivo. The two nucleoside transport inhibitors, at concentrations which would protect mammalian cells, did not protect promastigotes of L. donovani or L. m. mexicana from the toxic effects of tubercidin. Tubercidin, both alone or in combination with these inhibitors, was toxic to the promastigotes of the two species with approximate LD50s of 0.1 muM and 0.2 muM , respectively, and an approximate MLC of 1 muM for both species. When used alone, tubercidin proved highly toxic to PECs at all concentrations tested (1-10 muM) . These cells were protected from the toxicity of tubercidin by nitrobenzoylthioinosine and dipyridamole. Treatment of infected peritoneal exudate cells with the drug combination did not result in a reduction in total parasite numbers or the number of cells infected. In vivo studies using tubercidin alone or in combination with either dipyridamole or NBMPR confirmed that these inhibitors lessened the toxicity of tubercidin to mice although there was no reduction in the parasite load of infected animals treated with the combination. These results indicate that, unlike the situation reported for malaria parasites, Leishmania does not appear to change the mechanism of uptake of nucleosides into the host cell. Investigations of conditions prevailing in the parasitophorous vacuole of Leishmania infected cells and their importance to parasite survival were carried out by the use of methlyamine, ammonium chloride and dextran sulphate to modify them. The use of methylamine and ammonium chloride to raise the pH of the parasitophorous vacuoles did not affect the growth of L. m. mexicana in PECs but both the growth and survival of L. donovani amastigotes was greatly impaired. In similar experiments dextran sulphate affected the growth of both species of Leishmania equally, but the cause of this effect remains unclear. In a preliminary study, the effect of pH on the uptake and incorporation of adenosine and leucine by different species and stages of Leishmania was also determined. Interestingly, the optimum pH for uptake by metacyclics of L. major (pH 4-5) differed from that of the other promastigotes investigated (pH 6-7) and could represent a preadaption of these forms to life in the lysosomal system of macrophages. Taken together the results of the uptake and incorporation studies and the results of manipulating the lysosomal pH, suggest that L. m. mexicana amastigotes may be adapted for life at a higher pH than L. donovani. This may reflect differences in the survival stratagies of these two species of Leishmania.

The following thesis is an in-depth actor analysis chronicling my approach to the role of Iago in TheatreUNO’s 2019 production of Othello by William Shakespeare. This thesis will include analysis of the text, character objectives, techniques used, observations about the application of contemporary realistic acting technique to classical verse text, self-evaluation and personal reflection. This thesis will be supported by production materials including a fully scored script. This play was directed by David W. Hoover, and performed April 25- May 4, 2019,as part of the TheatreUNO 2018-2019 academic season, presented by the Department of Film and Theatre in the School of the Arts, at the University of New Orleans, New Orleans, Louisiana. Scenic Design was by Kevin Griffith, Lighting design was by Diane Baas, Costume design was by Anthony French, Vocal coaching was by L. Kalo Gow, and Alexandra Marie Rainey served as the Stage Manager.

The Surface Site Interaction Point (SSIP) model describes the non-covalent interaction properties of molecules by abstracting a discrete number of points on the van der Waals surface of molecules. Each point is assigned a value based on empirical interaction scales and the calculated Molecular Electrostatic Potential (MEP). SSIPs have been used to provide predictions of partition coefficients, solvent effects on association constants for formation of intermolecular complexes, and the probability of cocrystal formation. In this thesis, secondary electrostatic interactions are shown to be highly overestimated at the van der Waals surface and to be more accurately described on electron density isosurfaces that lie closer to the nuclei. Interaction parameters calculated with these isosurfaces successfully account for the properties of arrays of multiple H-bond donor and acceptor groups in different configurations. Three MEP isosurfaces are required to describe soft H-bond acceptors, hard H-bond acceptors, and H-bond donors. The Atomic Surface Site Interaction Point (AIP) model has been developed to obtain interaction points on these three surfaces using empirical rules for different atom types. This new approach to obtain interaction sites ensures a correct description of secondary electrostatic interactions, an accurate placement of lone pairs, a consistent description of π-systems and a representation of short H-bond contacts with hard acceptors but longer contacts with soft acceptors. Partition data between n-hexadecane and water was used to fine-tune the AIP representation of non-polar functional groups, for which it is difficult to obtain accurate empirical interaction parameters. The phase transfer data is also used to analyse the effect of H-bond cooperativity on the AIPs of functional groups that can make more than one H-bond, like alcohols, ethers and carbonyls. Finally, two methods for fast calculation of AIPs are discussed. The first method is a fragment-based approach, which assigns AIPs of large compounds from the AIP representation of small molecules with matching substructures. The second approach relies on a neural network method developed by Astex to quickly calculate the MEP surface and obtain the AIPs. These methods extend the scope of the AIP model to describing large molecules or large libraries of compounds for applications such as virtual screening and modelling host-guest systems.

Considerable progress has been made in the Hunter group towards the development of sequence oligomers equipped with H-bond donor and acceptor recognition units, which are able to assemble into duplexes by H-bonding between sequence-complementary oligomers. This thesis describes a new class of melamine oligomers composed of alternating triazine and piperazine units, which are equipped with phenol and phosphine oxide recognition groups. The order of the recognition groups defines the sequence of the oligomers. Complete sequence library of 1-mers, 2-mers and 3-mers, along with the homo 4-mers were synthesised by sequential temperature-controlled nucleophilic aromatic substitutions between cyanuric chloride and secondary amines. Complementary homo-oligomers undergo cooperative duplex formation, and hetero 3-mers form sequence-selective duplexes. H-bond templated synthesis of a similar melamine oligomer was attempted in toluene, but the template was inefficient at promoting the formation of sequence-complementary oligomers. The central H-bonding recognition unit of the melamine 3-mers was replaced by benzaldehyde or aniline side chains, giving oligomers that could assemble by imine formation as well as H- bonding. The 3-mer bearing two phosphine oxides and a benzaldehyde was converted to an imine with excess aniline, and then subjected to transimination in CDCl3 with the 3-mer bearing two phenols and an aniline. Transimination reached equilibrium at 70% conversion. The product duplex never fully assembled, indicating geometric incompatibility between the chosen H-bonding and dynamic covalent base pairs. Previously, a family of oligotriazoles equipped with phenol and benzoic acid recognition units was developed in the Hunter group, and shown to be capable of sequence information transfer by covalent templated synthesis of new oligomers. However, there are limitations associated with the choice of triazole backbone used in these systems. Here a novel strategy was developed for the rapid discovery of diazide and dialkyne building blocks for the synthesis of alternative backbones. Supramolecular scaffolds were created by mixing bidentate ligands and a metalloporphyrin appended with a dialkyne. The scaffolds were trapped by copper-catalysed azide alkyne cycloaddition with different diazides. The longest bidentate ligands gave the highest yield of linear triazole oligomers with any of the diazides used. No diazide gave the linear triazole oligomer as the major product with the dialkyne studied. A different backbone made by ring opening metathesis polymerisation was also investigated. An attempt was made for the synthesis of new oligomers from norbornenes functionalised with phenol and benzoic acid recognition units. Metathesis polymerisation gave a mixture of stereoisomers, and the monomers did not undergo successful base pair formation and cleavage cycle, making this system unsuitable for further studies.

Oxygenic photosynthesis plays a pivotal role at the very heart of global ecosystems, providing the food, fuel and oxygen that sustains virtually all life on Earth (Hohmann-Marriott and Blankenship, 2011). Despite the essential and highly intricate role that photosynthesis plays on Earth, the actual process of photosynthesis appears to be remarkably inefficient with only ~ 9-12% of useable solar energy (wavelengths between 400 – 700 nm) being converted to biomass (Zhu et al., 2010). Given the rising demands on the global food chain associated with climate change and a rising population, it is widely recognised that improvements in the efficiency of this vital process will be required to ensure food security for an ever-increasing population over the coming decades (Long et al., 2015; Zhu et al., 2010). Among the multiple targets which have been identified for potential improvement is cytochrome b6f (cytb6f), an integral membrane complex found at the heart of oxygenic photosynthesis. As well as facilitating the rate-limiting step in light dependent electron and proton transfer, the cytb6f complex also plays a key role as a redox-sensing hub in higher plants involved in the regulation of light-harvesting, electron transfer, photosynthetic gene expression and adaptation to environmental stress. Together, these characteristics make cytb6f a judicious target for genetic manipulation to enhance photosynthetic yield and promote stress tolerance in crop plants. While a number of studies show great promise in this regard (Simkin et al., 2017), further progress is hindered by the lack of a detailed understanding of the structure and function of the cytb6f complex from higher plants. Here we present the first structures of the cytb6f complex from a higher plant (Spinacia oleracea), shedding light on the internal mechanics of the Q-cycle and providing new clues as to how this extraordinary complex fulfils its various roles in photosynthetic regulation. We offer further opportunities to explore these insights by presenting a second structure, from the model cyanobacterium Synechocystis sp. 6803. Together these structures provide a number of key mechanistic insights into the cytb6f complex, many of which may now be further explored through structure-based mutagenesis of the Synechocystis complex and molecular dynamics simulations.

Nature stores biological information in form of a four-letter alphabet within the polymeric chain of DNA. Here, we have designed a series of triazine-based oligomers equipped with hydrogen bond acceptor (A)
 and donor (D) sites, which should lead to duplex assembly and template-directed synthesis, i.e. synthetic analogues of DNA. The oligomers are composed of four components: a recognition-based pairing system, backbone, linker and solubility controlling moieties. The oligomers were synthesised using the selective reactivity of trichlorotriazine. Two generations of s-triazine-based homo-sequence oligomers bearing either hydrogen-bond donor or hydrogen-bond acceptor recognition units were synthesised, and their assembly properties were studied via NMR titration experiments. The value of the association constant for the first generation homo-sequence dimers was within the range expected for a single hydrogen bond. This suggests that, in the solution state, these systems form aggregates rather than canonical duplex structures. However, the second generation of length-complementary homo-sequence dimers and trimers demonstrated the desired duplex formation. Therefore, these synthetically accessible systems are promising prototypes for stable information molecules, with the potential to encode and replicate chemical information in the same way as DNA. As the first step towards the synthesis of mixed-sequence information oligomers, an s-triazine based hetero-sequence dimer was synthesised, and the competing equilibrium between folding and duplex assembly was investigated. Strategies for the formation of branched-chain macromolecules with up to nine recognition modules were explored by attaching the second-generation homo-sequence trimers to an s-triazine core.

Cell membranes coordinate a large variety of biological processes by selectively recognising and responding to different external stimuli, and membrane-spanning proteins play a vital role in these signalling pathways. A large number of examples of synthetic membrane channels and transporters have been reported in the past four decades. However, signal transduction without mass transfer is considerably more challenging. In this dissertation, an indirect artificial transmembrane signalling mechanism which operates by controlled translocation of a synthetic transducer across the lipid bilayer was investigated. The fundamental concept of the translocation mechanism is the switching of membrane-permeability of the two head groups of the transducers. The recognition head group of the transducer becomes membrane-permeable in response to an external chemical stimulus, which leads to membrane translocation, exposing a catalytic head group to the interior of the vesicle. Catalytic hydrolysis of an internal substrate generates an amplified output signal. Previously reported examples showed that the transducer could respond to different external stimuli, such as pH (hydroxide ions) or metal ions. Herein, we present efforts towards generalising the concept and extending the scope of this mechanism into more biological systems. Firstly, a maleimide transducer was designed as a "stem transducer" to which a wide range of recognition groups could be attached in situ by using maleimide-thiol conjugation chemistry. Secondly, a carboxylic acid transducer was studied in an attempt to achieve controlled cargo-release in response to an acid input. Thirdly, a vesicle-to-vesicle communication system was assembled with a desthiobiotin transducer by leveraging the desthiobiotin-avidin-biotin system. This example represents a key step towards designing artificial cell-like compartments that communicate in a similar way to cells. Furthermore, we explored an analogue of the β-galactose transducer and the viability of using enzymatic cleavage as an input on the membrane surface. Finally, 19F NMR studies were conducted to provide insight into the positioning of the catalytic head groups of transducers in the membrane, and a fluorescence quenching assay was used to determine the ion transport ability of transducers. This work provides further understanding of the proposed membrane translocation mechanism and extends the scope of artificial transmembrane signal transduction from purely synthetic assemblies into more sophisticated biological systems. This opens up the potential for the future development of intelligent responsive vesicles in bionanotechnology.

Intermolecular interactions, including hydrogen bonding, are important for governing many processes, including solvation, protein ligand binding and crystallisation. Previously in the Hunter group, the Surface Site Interaction Point (SSIP) model of intermolecular interactions has been used to describe molecules as a set of discrete hydrogen bonding sites. In this thesis I describe the prediction of phase properties using this molecular description, after giving an introduction to the wider area of phase property prediction. Experimental equilibrium constants for formation of hydrogen bonded complexes was collated to allow for the reparameterisation of the relationship used to convert calculated electrostatic potentials into the hydrogen bond parameters used to describe the interaction properties of SSIPs, and a curated database of this information was created. An overhaul of the software infrastructure, to allow greater exploitation of automation in the workflow, was undertaken. Canonicalisation of data formats for information produced during the calculation has also been undertaken to provide a foundation for work in the following chapters. Calculation of partition coefficients for a series of molecular datasets have been used to benchmark the performance of the surface site interaction model for liquids at equilibrium (SSIMPLE) which uses the SSIP description for molecules to calculate free energies. Functional Group Interaction Profiles (FGIP) describe the energy change of two solute SSIPs interacting as a function of solute SSIP values. These profiles provide insight into the strength of interactions within different solvents. A selection of profiles for a range of solvents are included as examples. The profiles provide a useful guide for how to tune interactions when designing systems which rely on intermolecular interactions for association. Consideration of the solvation free energy of a single SSIP in a solvent as a function of SSIP value, has led to the development of a metric for solvent similarity. The comparison of solvation free energy curves for different solvents and solvent mixtures led to the construction of similarity dendrograms that can be used for solvent selection in experimental systems. Expansion of the approach to be used to examine the temperature dependence of the interactions, allowed the exploration of vapour liquid equilibria.

Nature uses multivalency as one of the most important governing principles to control selective molecular recognition and assembly. By combining a large number of weak interactions, it is possible to obtain high affinity, selective and reversible non-covalent binding processes. Multivalency has also become an important tool in the design of synthetic molecular systems. The result of multiple binding events is not just a simple sum of individual contributions due to cooperative interactions between binding sites. The main part of this thesis deals with the study of chelate cooperativity in multivalent supramolecular systems. Firstly, a well-known H-bonded rosette system was revisited and the effective molarity was determined experimentally by 1H NMR titrations to be around 2 M, which is a high chelate cooperativity compared to other supramolecular systems. Moreover, the concept of peripheral crowding in solution was revisited, since rosettes based on less bulky pyrimidines showed higher stabilities and effective molarities than the rosettes based on bulky pyrimidines. The following two chapters deal with efforts towards a supramolecular system inside a porphyrin nanoring. The porphyrin nanoring shows the highest value of effective molarity reported in the literature and is, therefore, a great system to study the cooperative behaviour when a covalent ligand is replaced with a supramolecular system. The first studied system was based on small molecules containing simple hydrogen-bond acceptors and donors. Unfortunately, solubility issues led to the termination of the project. The second system used the hydrogen-bonded rosette motif. A number of different pyridine-pyrimidine and pyridinebarbiturate ligands were synthesised and their assembly inside the porphyrin nanoring was studied in detail by UV-vis-NIR experiments. The effective molarities for the sequential binding of the rosette systems to 6-ring were determined to range from 0.23 to 3.7 M, which is significantly lower compared to the system that utilised a covalent hexadentate ligand (126 M). The final part of the thesis introduces a new class of hybrid hydrogen-bonded/metalcoordinated cages based on the rosette motif. These complexes are a rare example of architectures where both hydrogen-bonding and metal-coordination form the crucial part of the topology of the complex since if either is removed, the architecture changes drastically.

Nature has long inspired chemists to replicate the molecules produced by evolution. Arguably, the most important of these are the nucleic acids because of the ability to store and transfer information through duplex formation using Watson-Crick base pairing. Biochemists have prepared modified DNA analogues, in which the phosphate diester units used for synthesis, the bases used for recognition, and the sugar backbones have all been replaced. These systems have been found to form stable duplexes, so it is clear that the precise structure of these three modules is not crucial for information manipulation through a sequence-selective duplex formation. This non-uniqueness of the structure of the nucleic acids with respect to their function provides a challenge for synthetic chemists to design information molecules capable of directed evolution. A range of oligomeric and polymeric materials has been reported that are capable of duplex-formation and site-specific recognition, but few functional materials based on a sequence of supramolecular interactions are known. Herein, we present efforts towards a new family of oligomers that contain a sequence of hydrogen-bonding recognition sites, used as the bits for binary data encoded in an organic information molecule. Several monomer designs were implemented and investigated, and the final system uses single-point hydrogen bond recognition motifs between electron-deficient phenols (D) and electron-rich phosphine oxides (A), which provide strong interactions in non-polar solvents (K$_{A·D}$ ≈ 4000 M$^{−1}$ in toluene). Ester chemistry was employed for the synthesis of the corresponding homo- and heterodimers, exploiting the robustness of the ester bonds and the ease of their synthesis. A trifluoromethyl group incorporated into the structure of D enhanced the strength of the hydrogen bonds and provided a convenient probe to study the association through $^{19}$F NMR spectroscopy. The strongly hydrogen-bonding recognition motifs were observed to cooperatively form sequence-complementary duplexes with high fidelity and without substantial intramolecular folding. Those promising results led to the investigation of supramolecular behaviour of longer oligomers. An ADAD tetrame was successfully synthesised and its molecular structure was elucidated. Supramolecular association of the ADAD 4-mer was investigated through NMR spectroscopy and the results suggest that the room temperature ADAD exists as a stem-loop that further assembles in a manner akin to kissing interactions of single-stranded nucleic acids. These results lay strong foundations for the future development of new functional materials based on synthetic information molecules.

The nucleic acids contain chemical information in the form of a sequence of bases. This information content is expressed through sequence selective duplex formation and template directed synthesis. To date, the only programmable artificial information molecules that can truly rival the nucleic acids, in terms of their function, are structurally very similar to the nucleic acids. This thesis describes a synthetic approach to duplex forming hydrogen bonding oligomers that contain information in the form of a sequence of H-bond donor and acceptor groups, in the pursuit of a programmable material that is orthogonal to the nucleic acids. Chapter 1 is a literature review of natural and synthetic information molecules and their applications in nanotechnology, including an overview of the structurally reengineered versions of the nucleic acids, foldamers, template polymerisation and synthetic duplexes. The review highlights the absence of totally synthetic information oligomers, that are orthogonal to the nucleic acids, and Chapter 2 sets out the aims of this thesis, which is to address this gap. Chapter 3 describes the synthesis of oligomers equipped with phenol H-bond donors and phosphine oxide H-bond acceptors. Through cooperative H-bond formation, these oligomers form double stranded complexes, which were characterised by NMR titrations and thermal denaturation experiments. For each additional H-bond there is an order of magnitude increase in association constant. In Chapter 4 it is demonstrated that the modular design for the oligomers in Chapter 3 represents a general strategy to synthetic information oligomers. Two new classes of H-bond acceptor oligomer were synthesised, bearing pyridine and pyridine N-oxide groups. Both these systems also exhibit cooperative duplex formation with H-bond donor oligomers, which were characterised by NMR titration. Chapter 5 examines the ability of mixed sequence 3-mers formed of H-bond donors (phenol) and H-bond acceptors (pyridine N-oxide) to form duplexes in a sequence selective manner. All 8 combinations of donor and acceptor were synthesised, and NMR titrations were used to measure the association constants for each pairwise combination of oligomers. Sequence matched duplexes generally have the highest association constants, but there are some anomalies.

Chapter 1 – Introduction Chapter 2 – Synthesis, characterisation and manipulation of a three component self-assembled system Chapter 3 – Development and utilisation of a fluorescence displacement assay for guest screening Chapter 4 – Prediction of guest binding using molecular docking Chapter 5 – The use of pH changes to control guest binding in water Chapter 6 – Highly efficient catalysis of the Kemp Elimination in the cage cavity.