Determination of testosterone and related compounds in body fluids is of utmost importance in doping control and the diagnosis of many diseases. Capillary electromigration techniques are a relatively new approach for steroid research. Owing to their electrical neutrality, however, separation of steroids by capillary electromigration techniques requires the use of charged electrolyte additives that interact with the steroids either specifically or non-specifically. The analysis of testosterone and related steroids by non-specific micellar electrokinetic chromatography (MEKC) was investigated in this study. The partial filling (PF) technique was employed, being suitable for detection by both ultraviolet spectrophotometry (UV) and electrospray ionization mass spectrometry (ESI-MS). Efficient, quantitative PF-MEKCUV methods for steroid standards were developed through the use of optimized pseudostationary phases comprising surfactants and cyclodextrins. PF-MEKCUV proved to be a more sensitive, efficient and repeatable method for the steroids than PF-MEKCESI-MS. We discovered that in PF-MEKC analyses of electrically neutral steroids, ESI-MS interfacing sets significant limitations not only on the chemistry affecting the ionization and detection processes, but also on the separation. The new PF-MEKCUV method was successfully employed in the determination of testosterone in male urine samples after microscale immunoaffinity solid-phase extraction (IA-SPE). The IA-SPE method, relying on specific interactions between testosterone and a recombinant anti-testosterone Fab fragment, is the first such method described for testosterone. Finally, new data for interactions between steroids and human and bovine serum albumins were obtained through the use of affinity capillary electrophoresis. A new algorithm for the calculation of association constants between proteins and neutral ligands is introduced.

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Presenting practical approaches to complex formulation problems, this outstanding reference provides a thorough overview of particulate delivery systems-emphasizing specific preparation, characterization, and evaluation methods, as well as potential applications in areas such as pharmacy, medicine, cosmetology, and agriculture.

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Self-assembly of molecules and supramolecules is one of the fundamental phenomena in chemistry, physics, biology and material science. For example biological systems, like lipid bilayers of cell membranes and tertiary protein structures are formed by spontaneous self-assembly. Conformation and properties of these assemblies can be affected by changing the local environment of the structures. In the case of biological molecules, such an example would be protonation or deprotonation by changes in pH. When changing the conformation, one often changes the collective properties of the molecular assemblies.
In this thesis, the formation of functional nanoscale devices is approached from the self-assembly of molecules and metallic monolayer capped nanoparticles into superstructures consisting of numerous nanoparticles. Stabilisation of the individual nanosized particles is based on bonding between noble metals and thiol ligands. The desired chemical characteristics and functionality of the nanoparticles is achieved by choosing the capping ligand layer and thus, directing the interactions between the nanoparticles. Both formation and functionality of the superstructures are studied in this thesis. Syntheses of silver and gold nanoparticles capped with different ligands are included. Both the individual nanoparticles and the colloidal superstructures formed by them were characterised by transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta-potential measurements and UV-vis spectroscopy. Characterisation of the electrical properties of the self-assembled structures were carried out by scanning electrochemical microscopy (SECM).