Advanced polymer-based drug delivery systems for chemotherapy

The research in this thesis attempts to help reduce the side effects of current cancer treatments via targeted drug delivery. This was achieved by developing advanced polymer-based delivery systems for chemotherapeutic agents by using different techniques such as: electrohydrodynamic techniques, which include electrospinning and electrospraying, in addition to spray drying. The fabrication of fibres and particles was achieved using single fluid electospinning and electrospraying as well as to side-by-side structures and triaxial fibres. Chapter 1 is a brief introduction of cancer and its current treatments where their benefits and limitations are critically discussed. Then, the importance and advantages of drug delivery systems in cancer therapeutics are explored. Finally, the fabrication of these delivery systems by electrospinning and spray drying is reviewed. After a detailed overview of the research field, the scientific gaps are identified and the overall aims of the experimental work on this thesis are outlined. In Chapter 2, electrospinning and electrospraying techniques were used to generate drug-loaded Janus fibres and particles made of polyvinylpyrrolidone (PVP) by using a side-by-side spinneret. A photo-chemotherapeutic formulation was created by using rose bengal and carmofur, where the formulation created by electrospraying achieved a high selectivity towards lung cancer cells. Chapter 3 describes the production of formulations in the form of fibres or particles composed of a polyvinylpyrrolidone (PVP) matrix and tristearin (GTS) by electrohydrodynamic techniques. These precursor formulations were used as templates to fabricate aqueous-dispersible, drug loaded SLNs. Indomethacin (BCS class 2), and 5FU a chemotherapeutic agent were used. Chapter 4, builds on the work from Chapter 3, and details the scale-up production of the polymer-based templates to create SLNs, it also compares the electrohydrodynamic techniques with spray drying. Chapter 5 focuses on using triaxial electospinning to create a template which upon hydration self-assembles in snowman Janus nanoparticles. These Janus nanoparticles create a photo chemotherapy formulation, which constitutes of a micelle containing hematoporphyrin and a liposome entrapping carmofur