Theses & Dissertations

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https://hdl.handle.net/20.500.14170/194

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Browsing Theses & Dissertations by Author "Ahmad Huzaifah Mohd Yusoff"
  • Publication
    Magnetite – Hydroxyapatite nanoparticles functionalized with Catechin for the potential treatment of cancer
    ( 2019)
    Ahmad Huzaifah Mohd Yusoff
    The use of bioactive flavonoids from herbal plant is an emerging strategy for treating cancer in overcoming myriad of toxic effects from chemotherapeutic drugs. However, the non-specific distribution of flavonoid compounds limits the therapeutic dose withincancer cells. In recent years, nanoparticles have a great interest in acting as nanocarriers to increase the concentration of drugs at the desired site. This thesis present on the development of suitable nanocarriers for catechin flavonoid delivery. A nanoscale structure composed of magnetic core of magnetite nanoparticles and multifunctional hydroxyapatite (HAp) shell were developed as a nanocarrier. It is known that the effectiveness of nanocarrier transportation is mainly governed by their size. In view of this argument, magnetite nanoparticles that were prepared using co-precipitation method were studied based on the effects of different processing conditions towards the final size. The production of magnetite were carried out by varying the stirring rate, temperature of reaction and pH of solution. In addition, a neural network named Hybrid Multi-Layered Perceptron Network (HMLP) was used to model and predict the optimum processing condition that yield smallest size of magnetite nanoparticles. It was found that the optimum processing parameters to yield smallest size of magnetite predicted by HMLP are at stirring rate of 725rpm, temperature of 60°C and pH of 12.15 with predicted size of 8.81nm. The real experimental study then revealed that magnetite production at thepredicted parameters give a size of 8.69nm, which was a very small error of 1.36%. Subsequently, that smallest magnetite obtained were introduced with HAp coating layervia rapid sol-gel route. The aim of HAp coating layer were to avoid agglomeration issue arises from bare magnetite, enhancing the safety profile of nanoparticles and improving the efficacy of catechin transportation. Incorporation of HAp onto magnetite surfaces resulted in changes in the surface morphology as well as their magnetism properties. It was observed that a core-shell structure was formed with the resulting particles having an average diameter of 48.26nm. In addition, based on structural analyses, HAp layer demonstrated a high phase purity with the phase composition close to the naturally occurring human bones. However, the magnetic saturation value were found to be slightly decrease than that of bare magnetite which due to the diamagnetic HAp layer. In order to investigate the adsorption properties of the nanocomposites, catechin, a most abundant flavonoid compound present in Ficus deltoidea leaf was selected as a therapeutic agent and adsorbate. The adsorption studies were conducted in a series of batch experiments. The adsorption isotherm studies showed that the data were best fitted to a Langmuir model indicating a monolayer adsorption of catechin onto homogenous nanocomposites surfaces had taken place. Furthermore, the adsorption kinetic studies has demonstrated a good correlation with pseudo-second-order kinetics suggesting that the rate of catechin adsorption were chemically rate controlling. Finally, in vitro studies of magnetite-HAp catechin nanocomposites (nano-MHC) were performed on breast cancer cell. Cellular toxicity of nanoparticles was significantly affected by constant magnetic field exposure. However, cellular uptake under the present of magnetic field was limited due to magnetically-induced nano-MHC aggregates on the cell surfaces.
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