In the first part of this thesis, it was found by fibre-optic fluorescence spectroscopy, that the greening of fabrics washed in optical brighteners is due to a reabsorption effect. The quantum yield of fluorescence of the optical brighteners OB15, OB36 and OB49 in water are 0.11, 0.08 and 0.71 respectively. Their respective fluorescence natural lifetimes are 6700±109, 5971±712 and 1685±22ps. In solution, the excited state of OB15 experiences more competing relaxation processes as the solvatochromic shift increases. OB49 displays the opposite trend. A literature cellulose model surface is employed as a cotton mimic for evanescent wave fluorescence studies. Two model greases are similarly developed and used, and a third is presented for future work. These are based on surface-specific reactions with glass substrates, and the doping of a regenerated cellulose film with long chain alcohols. On doped cellulose surfaces, some low quantum yields occur compared to clean cellulose and bulk solution. Photobleaching behaviours are also observed. Both dyes physisorb rigidly to cellulose and grease models. The second part of this thesis identifies the pigment palette of the earliest Northumbrian manuscripts pre- and post-1066, by Raman and diffuse reflectance spectroscopy. It develops a suite of multispectral imaging programs in MATLAB for facile classification of pigments across a page ab initio, using data reduction and colour spaces. Raman and reflectance data are meta-analysed using symmetric permutation to split manuscripts and pigments into groups ab initio. It was also generalised, that the palette of the pre-Hastings selected manuscripts contained vergaut, indigo, orpiment, impure red lead, and copper green pigments, as well as orcein purples. Immediately post-1066 white lead, red ochre, vermilion and lapis lazuli appear in the palette in England, though vergaut and indigo disappear and the red lead used is essentially pure.

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Hydrophilic interaction chromatography (HILIC) has been the subject of a few excellent reviews in recent years and most focused on different factors which impact on the separation of compounds in HILIC mode including column temperature, mobile phase composition, pH, buffer type and concentration. However, there have not been as many studies focusing on the retention mechanism and selectivity in hydrophilic chromatography. In the light of recent development in HILIC stationary phases and their applications, the need to understand the mechanisms that govern the separation in HILIC, which is not purely due to partitioning, and the contribution of stationary surface became a subject of study. This thesis explored the possible mechanisms which might be involved in HILIC chromatography by comparing the retention of test probes on bare silica gel and on a type-C silica hydride phase. In addition, a comprehensive retention and selectivity study of some commercially available hydride-based stationary phases was carried out in the analysis of hydrophobic acids and bases in hydrophilic interaction chromatography (HILIC). The applications of HILIC technique were also addressed in the analysis of plasma and urinary metabolites, impurity profiling and in the separation of ‘Legal high’ regioisomers. An interest in the HILIC retention mechanism was mainly inspired by the need to understand how to develop the optimal HILIC conditions and the selection of a stationary phase. The retention of a series of positively charged probes on silica gel column was concluded that for this class of compounds both ion-exchange and hydrophilic partitioning were involved in retention. Ion exchange interactions were minimised by increase the ionic strength of the modifier in the mobile phase. The strength of the overall HILIC mechanism was increased with silica gel surface area. The unique properties of silica-hydride phases also assessed and are still not explained in terms of how the retention mechanism of this type of stationary phase is different from the other separation materials used in chromatography. The study confirmed the usefulness of HILIC in many analytical aspects. However, the mixed-interaction mechanisms which operate on different stationary phases for different compounds are still far from understood and more investigation is required.

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