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Item Nanoengineered polymers and other organic materials in lung cancer treatment: Bridging the gap between research and clinical applications(Elsevier Ltd, 2024-03-25) Jin X; Heidari G; Hua Z; Lei Y; Huang J; Wu Z; Paiva-Santos AC; Guo Z; Karimi Male H; Neisiany RE; Sillanpää M; Prakash C; Wang X; Tan Y; Makvandi P; Xu YCancer remains a major global health challenge, with increasing incidence and mortality rates projected for the coming years. Lung cancer, in particular, poses significant obstacles due to late-stage diagnosis and limited treatment options. While advancements in molecular diagnostics have been made, there is a critical need to connect the dots between laboratory and hospital for better lung cancer treatment. Systemic therapy plays a crucial role in treating advanced-stage lung cancer, and recent efforts have focused on developing innovative drug delivery techniques. Nanoparticles (NPs) have emerged as a promising approach to lung cancer treatment, offering enhanced drug delivery, active targeting, and reduced toxicity. Organic-based nanomaterials, like polymeric nanoparticles, solid lipid nanoparticles, and liposomes hold great potential in this field. This review examines the application of NPs in lung cancer treatment, highlights current therapies, explores organic nanoparticle-based approaches, and discusses limitations and future perspectives in clinical translation.Item The Effect of pH and Sodium Caseinate on the Aqueous Solubility, Stability, and Crystallinity of Rutin towards Concentrated Colloidally Stable Particles for the Incorporation into Functional Foods(MDPI (Basel, Switzerland), 2022-01-14) Rashidinejad A; Jameson GB; Singh H; Papetti APoor water solubility and low bioavailability of hydrophobic flavonoids such as rutin remain as substantial challenges to their oral delivery via functional foods. In this study, the effect of pH and the addition of a protein (sodium caseinate; NaCas) on the aqueous solubility and stability of rutin was studied, from which an efficient delivery system for the incorporation of rutin into functional food products was developed. The aqueous solubility, chemical stability, crystallinity, and morphology of rutin (0.1-5% w/v) under various pH (1-11) and protein concentrations (0.2-8% w/v) were studied. To manufacture the concentrated colloidally stable rutin-NaCas particles, rutin was dissolved and deprotonated in a NaCas solution at alkaline pH before its subsequent neutralisation at pH 7. The excess water was removed using ultrafiltration to improve the loading capacity. Rutin showed the highest solubility at pH 11, while the addition of NaCas resulted in the improvement of both solubility and chemical stability. Critically, to achieve particles with colloidal stability, the NaCas:rutin ratio (w/w) had to be greater than 2.5 and 40 respectively for the lowest (0.2% w/v) and highest (4 to 8% w/v) concentrations of NaCas. The rutin-NaCas particles in the concentrated formulations were physically stable, with a size in the range of 185 to 230 nm and zeta potential of -36.8 to -38.1 mV, depending on the NaCas:rutin ratio. Encapsulation efficiency and loading capacity of rutin in different systems were 76% to 83% and 2% to 22%, respectively. The concentrated formulation containing 5% w/v NaCas and 2% w/v rutin was chosen as the most efficient delivery system due to the ideal protein:flavonoid ratio (2.5:1), which resulted in the highest loading capacity (22%). Taken together, the findings show that the delivery system developed in this study can be a promising method for the incorporation of a high concentration of hydrophobic flavonoids such as rutin into functional foods.Item Hydrothermal synthesis of inorganic nanoparticles for potential technological applications : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2021) Etemadi, HosseinIron oxide nanoparticles (IONPs) are of interest in a diverse range of environmental and biomedical applications due to their intrinsic chemical, physical and thermal features such as superparamagnetism, high surface-to-volume ratios, high biocompatibility, low toxicity and easy magnetic separation. Many technological applications necessitate small (diameter < 20 nm) nanoparticles with narrow size distributions (< 5 %) and pronounced saturation magnetisation (Ms) for uniform physical and chemical effects. Historically, the synthesis of IONPs with controlled size and size distribution without particle agglomeration has proved challenging. In this thesis, we utilised an easy hydrothermal route and successfully synthesized two common phases of IONPs, namely Fe₃O₄ (magnetite) and α-Fe₂O₃ (hematite), using Fe(acac)₃ as iron source. By controlling the reaction conditions such as time, temperature, and the concentration of surfactants such as PVP and oleic acid, the different phases were selectively synthesized. The prepared nanoparticles were fully characterized with X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), energy dispersive X-Ray spectroscopy (EDS), atomic absorption spectroscopy (AAS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating-sample magnetometry (VSM), Brunauer-Emmett-Teller (BET) surface area measurements, photoluminescence (PL) and UV–Vis diffuse reflectance spectroscopy (UV–Vis/DRS). In Part I of this thesis, Fe₃O₄ and metal-doped spinel MxFe₃−xO₄ (M = Fe, Mg, Mn, Zn) nanoferrites were synthesised as agents for cancer treatment via a method called magnetic fluid hyperthermia (MFH). In Part II, α-Fe₂O₃ nanoparticles were hybridized with tin (II) sulfide (SnS) to create p-n heterojunction photocatalysts for efficient H2 production via ethanol photoreforming.Item Structure and properties of tunable Pickering emulsions : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry, Massey University, Manawatū, New Zealand(Massey University, 2019) Munro, Benjamin ChristopherThe ability to design soft-materials with targeted rheological properties is a vital part of the modern world. One type of soft-materials that are important across a range of industries from food and consumer goods, to paints and oil products are emulsions. Generally speaking, emulsions are mixtures of oil and water, with a stabiliser which controls the interactions between the droplets. Pickering emulsions are a subset of emulsions which utilise a solid nanoparticle stabiliser to increase droplet stability. Pickering emulsions are becoming increasingly attractive due to the wide, and varied, range of stabilisers available, along with the remarkable stability that these systems can have. Recently a number of workers have demonstrated the ability to tune the interactions between high volume fraction emulsions (with modifications prior to emulsification), resulting in the changes to the bulk strength of the emulsion systems and the droplet size distribution. Additionally, some unique yielding behaviour has been uncovered in certain situations, presenting an area which can be further investigated. The work presented in this thesis has developed low volume fraction emulsion systems with interactions between the droplets that were tuned post-emulsification. This was carried out through two distinct processes, modification of the Debye length with the addition of salt, and modification of the surface charge of the Pickering emulsifier by changing the pH of the aqueous phase. The results of this have demonstrated low volume percentage emulsions with interactions ranging from highly attractive through to repulsive between the droplets while maintaining a consistent droplet size. These new systems have demonstrated interesting rheological properties, with the attractive systems demonstrating significantly higher strength than anticipated. in certain cases these low volume percentage emulsion systems were demonstrated to show multi-stage yielding behavior, something that has previously only been seen for higher volume fraction systems. In addition to these properties, this work is thought to present the first case of a titania stabilised Pickering emulsion system with tunable interactions, demonstrating a new material for future development.Item From mathematical models to quantum chemistry in cluster science : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, Albany, New Zealand(Massey University, 2019) Trombach, LukasThe structures and stabilities of hollow gold clusters are investigated by means of density functional theory (DFT) as topological duals of carbon fullerenes. Fullerenes can be constructed by taking a graphene sheet and wrapping it around a sphere, which requires the introduction of exactly 12 pentagons. In the dual case, a (111) face-centred cubic (fcc) gold sheet can be deformed in the same way, introducing 12 vertices of degree five, to create hollow gold nano-cages. This one-to-one relationship follows trivially from Euler’s polyhedral formula and there are as many golden dual fullerene isomers as there are carbon fullerenes. Photoelectron spectra of the clusters are simulated and compared to experimental results to investigate the possibility of detecting other dual fullerene isomers. The stability of the hollow gold cages is compared to compact structures and a clear energy convergence towards the (111) fcc sheet of gold is observed. The relationship between the Lennard-Jones (LJ) and sticky-hard-sphere (SHS) potential is investigated by means of geometry optimisations starting from the SHS clusters. It is shown that the number of non-isomorphic structures resulting from this procedure depends strongly on the exponents of the LJ potential. Not all LJ minima, that have been discovered in previous work, can be retrieved this way and the mapping from the SHS to the LJ structures is therefore non-injective and non-surjective. The number of missing structures is small and they correspond to energetically unfavourable minima on the energy landscape. The optimisations are also carried out for an extended Lennard-Jones potential derived from coupled-cluster calculations for the xenon dimer, and, although the shape of the potential is not too different from a regular (6,12)-LJ potential, the number of minima increases substantially. Gregory-Newton clusters, which are clusters where 12 spheres surround and touch a central sphere, are obtained from the complete set of SHS clusters. All 737 structures result in an icosahedron, when optimised with a (6,12)-LJ potential. Furthermore, the contact graphs, consisting only of atoms from the outer shell of the clusters, are all edge-induced sub-graphs of the icosahedral graph. For higher LJ exponents the symmetry of the potential energy surface breaks away from the icosahedral motif towards the SHS landscape, which does not support a perfect icosahedron for energetic reasons. This symmetry breaking is mainly governed by the shape of the potential in the repulsive region, with the long-range attractive region having little influence.Item Filamentous phage derived biological nanorods : development of a novel display system : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Microbiology at Massey University, Manawatū, New Zealand(Massey University, 2018) Davey, Georgia RoseThe Ff filamentous bacteriophage are filament-like bacterial viruses approximately 900 nm in length. The F-pilus-specific filamentous phage are resistant to heat, pH-extremes, and detergents in combination with their structural properties and amenability to DNA recombinant engineering has enabled their extensive use in modern biotechnology. However, the use of Ff-phage in vaccines and other such biological uses is controversial due to their ability to replicate in gut Escherichia coli, and the possibility of mobilisation and horizontal gene transfer of antibiotic resistance-encoding genes among the gut bacteria. As such, the novel system was established to create short, stable particles that cannot replicate, called NanoZap particles. However, this system has the disadvantage of often producing multiple-length particles, rather than the desired single-length particles; another disadvantage is that during packaging, one particle in a million packages the entire plasmid due to recombination that removes the terminator copy of the (+) ori, and given that these plasmids contain antibiotic resistance genes, this likely would spread antibiotic resistance throughout the surrounding environment. In this thesis several variations upon the original pNanoZap vector were created and tested to obtain monodisperse unit-length particles. The deletion of the complete multiple cloning site (MCS) that lied between the initiator and terminator of replication from the original pNanoZap vector achieved this aim. To eliminate rare antibiotic resistant particles that package the complete pNanoZap vector, the antibiotic resistance gene was removed from the pNanoZap 537 vector and replaced with an auxotrophic marker nadC; this vector was named pNanoZap 537N. It is yet to be seen if this new pNanoZap vector is capable of producing NanoZap particles. For high-sensitivity diagnostics it is desirable to construct high-avidity particles, containing large number of detector molecules. To achieve this a double-display (detector displayed on phage which in turn is displayed on the surface of florescent E. coli) was designed and tested. When the E. coli expressing red fluorescent protein TinselPurple were infected with the bacteriophage, the chromogenic protein was lost, thereby showing that a different method of colouring E. coli will need to be used in order to construct the double-display particles.Item The effects of nanoparticles on the physical properties of type I collagen : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Chemistry at Massey University, Palmerston North, New Zealand(Massey University, 2016) Lian, JiaxinThis thesis concerned with the interactions of surface functionalized TiO2 and ZnO NPs with type I collagen. The collagen nanocomposites formed with TiO2 and ZnO NPs may be potential candidates for some biomedical applications thanks to the synergetic effects between two materials. How the physical properties of collagen have been changed when interacting with TiO2 and ZnO NPs has been investigated in this project. The general background and research objectives of this study are introduced in Chapter 1, followed by Chapter 2 which gives details about the preparation of the samples, in addition to the characterization techniques and protocols. The TiO2 and ZnO NPs were synthesized by colloidal synthetic methods and their surfaces were functionalized with different functional groups. The physical properties of the TiO2-collagen nanocomposites and ZnO-induced collagen gels were studied by rheology, DSC, swelling ratio assay, FTIR and confocal microscopy. The mechanical studies are the main focus of this thesis. In Chapter 3, TiO2 NPs coated with chitosan and PAA were introduced into collagen solutions before fibrillogenesis was carried out. They were found to affect the linear rheology of the collagen gels as a function of their concentration. There were no significant differences in the strain-stress response in the non-linear rheology. It was found that the PAA coated TiO2 NPs promoted collagen fibrillogenesis, resulting in thin fibrils, and a dense and more crosslinked structure, while the chitosan coated TiO2 NPs slowed down the collagen fibrillogenesis and created a heterogeneous network with thick fibrils and less crosslinks. ZnO-PVP NPs were found to induce collagen gelation without the use of the conventional fibrillogenesis involving gelation buffer, as reported in Chapter 4. The hydrogel formed with this method was found to be three times as strong as the gel formed with conventional gelation buffer at the same collagen concentration. Confocal images indicated those two gels have different molecular assembly states. A group of experiments showed ZnO acted as a neutralizing agent here to raise the pH of the collagen solution to the pH close to the isoelectric point of the collagen. Both the TiO2 and ZnO NP-collagen systems have demonstrated that different collagen networks can be created by the direct or indirect interactions between collagen monomer solution and the nanoparticles. By manipulating the assembly of collagen to design different networks, it is possible to achieve the physical properties required for different applications. The results are followed by the conclusions and future perspectives of this study.Item A systematic search for the global minimum structures of Cs, Sn and Au clusters and corresponding electronic properties : a thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Massey University, Albany, New Zealand(Massey University, 2007) Assadollahzadeh, BehnamClusters of atoms or molecules form the building blocks of nanoscience and are regarded as a new type of material, as they constitute a bridge between microscopic and macroscopic forms of matter. The experimental and quantum theoretical study of structures, chemical and physical properties and reactivities of nanoclusters represents an innovative and very active field of research, which has resulted in a wide range of applications. Independent of the model used to describe the bonding in these clusters, one of the prime objectives is to find the geometrical arrangement of the atoms or molecules, for a given cluster size, which corresponds to the lowest energy on the potential energy hyper-surface, the global minimum. In order to find such an arrangement, a density functional theory based genetic algorithm code, which is rooted in the Darwinian evolution concept of the survival of the fittest, is developed and utilized to systematically search for the global minimum isomers of homo-nuclear clusters consisting of up to twenty atoms of cesium, tin, gold and of nine atoms of copper. The performance of this algorithm is excellent as numerous energetically lower-lying cluster isomers (compared to those reported in the literature) are found. Extensive valence basis sets together with energy-consistent scalar-relativistic pseudopotentials are employed to optimize the geometry of these clusters and to calculate their electronic properties accurately at the density functional level of theory. Moreover, in collaboration with the Technische Universit??t Darmstadt, the mean static polarizability of tin clusters are measured by a beam deflection method. The qualitative agreement between measured and calculated dipole moments and static electric dipole polarizabilities of tin clusters up to twenty atoms is satisfactory, thus confirming the accuracy of the theoretical models used in this work. Furthermore, the performance of density functional theory in the field of metallophilicity is investigated for dimeric and trimeric [X-M-PH3] compounds (X = Cl, Br, I; M = Cu, Ag, Au) and it is found that the metallophilicity decreases down the group 11 elements of the periodic table of elements.