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Pupose: Cisplatin (CDDP), while amongst the most widely used chemotherapeutic drugs currently available, is well known to have a number of limitations, such as the lack of a single treatment approach and non-specific targeted therapies. Therefore, the development of an innovative strategy that could achieve localised CDDP treatment is an urgent undertaking. Recent advances in titania nanotube arrays (TNA) technology have demonstrated promising applications for localised chemotherapeutic drug treatment. The present work investigated the efficiency of a TNA nanosystem for the localised CDDP treatment of nasopharyngeal carcinoma (NPC). Methods: Two models of the TNA nanosystem were prepared: one consisted of CDDP loaded onto the TNA nanosystem surface (CDDP-TNA) and the other consisted of chitosan-coated CDDP-TNA. CDDP release from these two systems was comprehensively tested on the NPC cell lines NPC/HK-1 and C666-1. The NPC cytotoxicity profile of the two CDDP-TNA nanosystems was evaluated after incubation for 24, 48 and 72 h. Intracellular damage profiles were studied using fluorescence staining microscopic analysis with Hoechst 33342, acridine orange and propidium iodide. Results: The half-maximal inhibitory concentrations (IC50) of CDDP at 24 h were 0.50 mM for NPC/HK-1 and 0.05 mM for C666-1. CDDP in the CDDP-TNA and chitosan-coated CDDP-TNA models presented a significant degree of NPC inhibition (p < 0.05) after 24, 48 and 72 h of exposure. Fluorescence microscopy images revealed cellular damage and shrinkage of the cell membranes after 48 h of exposure to CDDP-TNA. Conclusion: This in vitro work demonstrated the effectiveness of TNA nanosystems for the localised CDDP treatment of NPC cells. Further in vivo studies are needed to support the findings.

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Titania nanotube arrays (TNA) have high biocompatibility, less toxicity, and a large surface area per volume; thus, TNA offer great potential in biomedical applications. Interactions between micro environment and cell on the TNA surface are intensively investigated regarding cell attachment and interaction. Anodization was used to create a highly ordered nano-porous oxide layer with nano-sized pores on the surface of the titanium. This process was carried out at 30 V with a sweep rate of 1 V/sec for a different duration (10 s, 1 min, 2 min, 5 min, 10 min, 20 min, 30 min, 1 h, 2 h, 3 h and 6 h). On an anodized titanium surface, the cell adhesion of several adherence cells was observed using a field emission scanning electron microscope (FESEM). Due to its important role in controlling the morphology of the nanotube structures, extending anodization time causes the length of the nanotubes increases. Hence, the optimised anodization time on the TNA surface at 30 V with a sweep rate of 1 V/s directly impacts cell adhesion after incubating for 48 h. The anodic potential of TNA was successfully obtained at 30 V with a sweep rate of 1 V/sec for 30 min, which could modulate diverse cellular responses of cell adhesion observed by FESEM.

Annealing is a crucial functional parameter relevant to the green synthesis and bactericidal properties of TiO 2 nanocomposites (TiO 2 -NPs). In this work, the effect of the annealing temperature on the physicochemical and bactericidal properties of TiO 2 -NPs obtained from Calotropis gigantea was comprehensively studied. The synthesised TiO 2 -NPs were characterised using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energydispersive X-ray spectroscopy, UV-Vis spectrophotometer and FTIR spectroscopy. The bactericidal properties were determined via the minimum inhibitory concentration (MIC) and Kirby-Bauer disc diffusion methods. The cytocompatibility of green TiO 2 was further investigated using broblast cells lines model.Results indicated that amorphous-phase TiO 2 -NPs were transformed into the anatase phase at 500 °C with a crystallite size of 40.9 nm and MIC of 100 mg/mL towards S. aureus (colony count reduction from 4.3 log 10 to 1.01 log 10 ). Whereas TiO 2 -NPs annealed at 400 °C demonstrated no bacterial reduction, TiO 2 -NPs annealed at 500 °C showed a moderate zone of inhibition of 6.33-6.83 mm towards Escherichia coli and Pseudomonas aeruginosa. Findings from this study found that TiO-500C nanocomposites concentration at 100 mg/mL is cytocompatible to the broblast cells lines with proliferation rate/activity higher than 116% after 24 h treatment. The plant-mediated nano-sized cubic and spherical anatase TiO 2 -NPs encapsulated bioactive green elements, such as carbon, sodium, magnesium, chlorine, potassium, calcium and sulphur, from the C. gigantea extract, ultimately leading to versatile and eco-friendly bactericidal agents with wound-healing properties. Further studies are necessary to support the ndings of this work.