Master of Science (Nanoscience) / Neuroblastomas (NBs) are the most common solid extra-cranial tumours diagnosed in childhood and characterized by a high risk of tumour relapse. Like in other tumour types, there are major concerns about the specificity and safety of available drugs used for the treatment of NBs, especially because of potential damage to the developing brain. Many plant-derived bioactive compounds have proved effective for cancer treatment but are not delivered to tumour sites in sufficient amounts due to compromised tumour vasculature characterized by leaky capillary walls. Betulinic acid (BetA) is one such naturally-occurring anti-tumour compound with minimum to no cytotoxic effects in healthy cells and rodents. BetA is however insoluble in water and most aqueous solutions, thereby limiting its therapeutic potential as a pharmaceutical product. Liposomes are self-assembling closed colloidal structures composed of one or more concentric lipid bilayers surrounding a central aqueous core. The unique ability of liposomes to entrap hydrophilic molecules into the core and hydrophobic molecules into the bilayers renders them attractive for drug delivery systems. Cyclodextrins (CDs) are non-reducing cyclic oligosaccharides which proximate a truncated core, with features of a hydrophophilic outer surface and hydrophobic inner cavity for forming host-guest inclusion complexes with poorly water soluble molecules. CDs and liposomes have recently gained interest as novel drug delivery vehicles by allowing lipophilic/non-polar molecules into the aqueous core of liposomes, hence improving the therapeutic load, bioavailability and efficacy of many poorly water-soluble drugs. The aim of the study was to develop nano-drug delivery systems for BetA in order to treat human neuroblastoma (NB) cancer cell lines. This was achieved through the preparation of BetA liposomes (BetAL) and improving the percent entrapment efficiency (% EE) of BetA in liposomes through double entrapment of BetA and gamma cyclodextrin BetA inclusion complex (γ-CD-BetA) into liposomes (γ-CD-BetAL). We hypothesized that the γ-CD-BetAL would produce an increased % EE compared to BetAL, hence higher cytotoxic effects. Empty liposomes (EL), BetAL and γ-CD-BetAL were synthesized using the thin film hydration method followed by manual extrusion. Spectroscopic and electron microscopic characterization of these liposome formulations showed size distributions of 1-4 μm (before extrusion) and less than 200 nm (after extrusion). As the liposome size decreased, the zeta-potential (measurement of liposome stability) decreased contributing to a less stable liposomal formulation. Low starting BetA concentrations were found to be more effective in entrapping higher amounts of BetA in liposomes while the incorporation of γ-CD-BetA into liposomes enhanced the % EE when compared to BetAL, although this was not statistically significant. Cell viability studies using the WST-1 assay showed a time-and concentration-dependent decrease in SK-N-BE(2) and Kelly NB cell lines exposed to free BetA, BetAL and γ-CD-BetAL at concentrations of 5-20 ug/ml for 24, 48 and 72 hours treatment durations. The observed cytotoxicity of liposomes was dependant on the % EE of BetA. The γ-CD-BetAL was more effective in reducing cell viability in SK-N-BE(2) cells than BetAL whereas BetAL was more effective in KELLY cells at 48-72 hours. Exposure of all cells to EL showed no toxicity while free BetA was more effective overall than the respective liposomal formulations. The estimated IC₅₀ values following exposure to free BetA and BetAL were similar and both showed remarkable statistically significant decrease in NB cell viability, thus providing a basis for new hope in the effective treatment of NBs.

Capillary electrophoresis (CE) is a modern analytical technique, which is electrokinetic separation generated by high voltage and taken place inside the small capillaries. In this dissertation, several advanced capillary electrophoresis methods are presented using different approaches of CE and UV and mass spectrometry are utilized as the detection methods. Capillary electrochromatography (CEC), as one of the CE modes, is a recent developed technique which is a hybrid of capillary electrophoresis and high performance liquid chromatography (HPLC). Capillary electrochromatography exhibits advantages of both techniques. In Chapter 2, monolithic capillary column are fabricated using in situ photoinitiation polymerization method. The column was then applied for the separation of six antidepressant compounds. Meanwhile, a simple chiral separation method is developed and presented in Chapter 3. Beta cycodextrin was utilized to achieve the goal of chiral separation. Not only twelve cathinone analytes were separated, but also isomers of several analytes were enantiomerically separated. To better understand the molecular information on the analytes, the TOF-MS system was coupled with the CE. A sheath liquid and a partial filling technique (PFT) were employed to reduce the contamination of MS ionization source. Accurate molecular information was obtained. It is necessary to propose, develop, and optimize new techniques that are suitable for trace-level analysis of samples in forensic, pharmaceutical, and environmental applications. Capillary electrophoresis (CE) was selected for this task, as it requires lower amounts of samples, it simplifies sample preparation, and it has the flexibility to perform separations of neutral and charged molecules as well as enantiomers. Overall, the study demonstrates the versatility of capillary electrophoresis methods in forensic, pharmaceutical, and environmental applications.