Heyne, Belinda JMKabanov, Vladimir2023-05-112021-09-24Kabanov, V. (2021). Singlet Oxygen Production and Its Kinetics in Nanoparticle-Photosensitizer Hybrid Systems (Doctoral thesis). University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca .http://hdl.handle.net/1880/11637810.11575/PRISM/dspace/41222Oxygen is inarguably among the most important molecules which sustain the majority of life as we know it. However, in its lowest excited state, singlet oxygen is a powerful cytotoxic agent capable of damaging DNA, proteins, and cell membranes. In medicinal context, production of singlet oxygen from light-activated drugs (photosensitizers) has been used to various degrees in photodynamic therapy to remove cancerous tumors, and in photodynamic inactivation of microorganisms to eliminate harmful pathogens. In the last decade, nanomaterials have emerged as a promising platform to establish control over the singlet oxygen production and advance the practical uses of photosensitization. Nevertheless, when compared to conventional chemotherapy as a means to treat diseases, or the use of common chemical agents to inhibit bacterial growth, application of nanomaterials for photodynamic processes in these areas is still in its infancy and substantial knowledge of understanding and controlling this approach is missing.The overarching goal of the work presented in this thesis is to provide molecular-level insight into the events taking place when nanomaterials are used to aid and manage photosensitized singlet oxygen production. To aid in this quest, the studies presented in this thesis looked at singlet oxygen generation from several common types of colloidal hybrid nanoparticle-photosensitizer materials. Silica- and liposome-based photosensitizing nanoparticles were employed to quantify singlet oxygen partition between the various local microenvironments inherent to each formulation, which fundamentally dictates the reactive species’ abilities to reach other substrates in solution or within the nanocarriers. Meanwhile, Ag and Au metal-based hybrid nanoparticles were used to understand how the metallic structure’s interactions with incident light can change the properties of a nearby photosensitizer and ultimately affect singlet oxygen generation.Methodologies, results, and conclusions discussed throughout the work presented herein aim to equip the research community with important layers of information to address the design of nanomaterials for photodynamic processes from the points-of-view of singlet oxygen and the photosensitizer. This in turn will enable the field to sort and tailor the countless possible hybrid nanoparticle-photosensitizer combinations for specific practical applications.EnglishPhotochemistryNanosciencePlasmonicsSinglet OxygenSpectroscopyKineticsNanomaterialsPhotodynamic ApplicationsChemistry--Physicaldoctoral thesis