Dissertations / Theses on the topic 'GREEN SYNTHESIZED'

>Magister Scientiae - MSc
Nature through billions of years of trial and error has produced an immeasurable amount of natural systems like plants, birds and animals. The intelligence of nature is hidden in these natural systems and researchers are turning towards “Nature’s intelligence” to find inspiration and advance novelty in the development of nanomaterials. Gold nanoparticles (AuNPs) have unique optical, electronic and physicochemical features which has gained them popularity and widespread exploitation in various applications. The conventional methods used for AuNPs synthesis employs toxic chemicals which makes these NPs unsafe for biomedical applications. Hence, there is a search for new, ‘green’ and more cost effective methods for AuNPs synthesis. Plant extracts are regarded as a highly desirable system for nanoparticle synthesis due to their tremendous capability to produce a wide range of phytochemicals that can act as reducing agents. The main goal of this study was to synthesize AuNPs in a cost effective manner without the use of toxic chemicals in the synthesis process. Avocado seeds which are an agricultural waste by-product were used for the biosynthesis of AuNPs. The study reports on the synthesis optimization, characterization and activities of the biogenic AuNPs. The avocado seed extract mediated - AuNPs (AvoSE-AuNPs) were optimized by varying reaction parameters and characterized by UV-visible, Dynamic Light Scattering (DLS) and High Resolution Transmission Electron Microscopy (HRTEM), Zetasizer and Fourier Transform Infrared Spectroscopy (FTIR). The formation of AvoSE-AuNPs had an absorption maximum at 534 nm. HRTEM and DLS confirmed that the NPs were polydispersed and present in different shapes. The presence of phytochemical constituents on the AvoSE-AuNPs were confirmed by FTIR. Their potential antibacterial activity was tested on bacterial strains known to exhibit resistance to a number of current antibiotics. The catalytic activity of AvoSE-AuNPs was also assessed as a means to contribute to the development of new methods aimed at alleviating organic pollutants such as nitrophenols in the environment. The AvoSE-AuNPs demonstrated excellent catalytic activity in the reduction of 4-NP by NaBH4 as shown by the rapid decrease in the nitrophenolate absorption band at 400 nm and the appearance of new absorption band at 298 nm, revealing the formation of the 4-aminophenol. Furthermore, the rate constants calculated demonstrated that the reaction occurs faster in the presence AvoSEAuNPs. The AvoSE-AuNPs showed low significant cytotoxicity. Cell cycle analysis was conducted to further investigate the apparent exhibited toxicity of the AvoSE-AuNPs. The results showed that in both cell lines treated with AvoSE-AuNPs and AvoSE there was a ii | P a g e disruption in the regulation of cell cycle. Cell cycle analysis helped improve understanding of the low cytotoxicity observed by the MTT assay results. The results presented in this study clearly demonstrate the feasibility of using AvoSE for the synthesis of AuNPs. This study demonstrated that AvoSE mediated AuNPs synthesis is a greener alternative as it abides by the green chemistry principles. Furthermore, the study outcomes contributed to minimizing environmental pollution by finding use for agricultural waste and thus ultimately adding value to the field.

>Magister Scientiae - MSc
The emergence of multiple drug resistant microorganisms poses a major threat to human life. These microorganisms have made the currently used antibiotics ineffective and therefore continue to thrive. Therefore, there is a need for development of new, broad-secptrum antibiotics which is effective against almost every infectious microorganism. These antibiotics should ensure high effectiveness against the infectious pathogens while it is less detrimental to human health. Thus the search is channelled in nanoscience and nanotechnology in order to develop antibiotics that can kill infectious microorganisms effectively and hindering the development of drug resistance by these microorganisms. Nanoscience is the study of properties of a material when reduced to it smallest size (below 100 nm). It is a newly developing field of science which includes chemistry, physics and biology and has made it easy to synthesise nanomaterials for applications in many sectors of life including in medicine. The synthesis of nanoparticles can be achieved by physical and chemical methods. However, these methods are energy and capital intensive. Additionally, chemical method of synthesis uses chemicals that may be toxic which restrict the use of resultant nanoparticles in medicine. Therefore, there is a need for the use of eco-friendly methods of nanoparticle synthesis. The synthesis of silver and gold nanoparticles in this study was carried out by a green synthesis method, at room temperature, using an aqueous extract from the endemic brown alga Sargassum incisifolium. For comparison, commercially available brown algal fucoidans were also used to synthesise these nanoparticle, in addition to conventional methods of synthesis. The formation of nanoparticles was followed by the use of UV-Vis spectrophotometry. The characterization of the nanoparticles was done by TEM, XRD, DLZ and FT-IR. The rate of nanoparticle formation varied with specific reducing agent used. The faster reaction rate was recorded with S. incisifolium aqueous extracts pretreated with organic solvents while extracts obtained without this pretreatment produced slightly slower reaction rates. However, the commercially available fucoidans were less effective and required elevated temperatures for nanoparticle formation. Sodium borohydride reduction of silver nitrate was faster than the biological methods while the reduction of auric chloride by the S. incisifolium extracts and sodium citrate proceeded at similar rates. The nanoparticles synthesised with the help of the untreated aqueous extract were bigger than those synthesised from pre-treated extracts with both giving irregular shaped of nanoparticles. Also the nanoparticles formed from commercially available fucoidans were not of the same size, with bigger sizes recorded with Macrocystis fucoidan and smaller sizes with Fucus fucoidan. The shapes of nanoparticles from these fucoidans were spherical. From the conventional method, the nanoparticle sizes were smaller compared to the green synthesised nanoparticles and were predominantly spherical. The silver nanoparticles synthesised from the Sargassum aqueous extracts showed excellent antimicrobial activity against five pathogenic microorganisms including A. baumannii, K. pneumoniae, E. faecalis, S. aureus, and C. albicans. The gold nanoparticles were much less effective. To adequately assess the antimicrobial activities of the nanoparticles, it is or paramount importance to also asses their cytotoxicity activity. Three cell lines were used in this study namely, MCF-7, HT-29 and MCF-12a. The silver nanoparticles were found to be toxic to HT-29 and MCF-7 cell lines, exhibiting sligtly less toxicity against MCF-12a cells. The gold nanoparticles showed lower toxicity but a similar trend was observed.

L’implantation de la Révolution verte a transformé les caféières, associant polyculture et élevage, en monocultures en fonction d’agrochimiques de synthèse. Pesticides, engrais et variétés hybrides à haut rendement et résistantes aux phytomaladies sont des dispositifs technoscientifiques au service du forçage des agroécosystèmes. Nous montrons comment le binôme monoculture/agrochimiques de synthèse a plongé les caféiculteurs dans une crise de valeurs, déterminée par un verrouillage technologique qui a emporté dans une spirale de dégradation la santé publique, la biodiversité des agroécosystèmes et la stabilité politique et économique des populations. Nous soulignons aussi comment les pratiques de pilotage des écosystèmes caféiers, proposées par l’agroécologie, favorisent un agencement pluraliste des valeurs et un déblocage du système technique. Cette thèse mène ainsi une analyse axiologique du sujet pluriel de la caféiculture technicisée dans le département colombien du Quindío
The Green Revolution has transformed the coffee culture, combining mixed farming and breeding, into single-crop farming depending on synthesized agrochemicals. Pesticides, fertilizers, and high yield hybrids varieties resistant to phyto-diseases are technoscientific devices aiming at forcing the agroecosystems. We show how the duo single-crop farming/synthesized agrochemicals has drowned the coffee producers into a value crisis determined by a technological lock down which took in a spiral of deterioration of public health, agroecosystem biodiversity, political and the economic stability of populations. We highlight as well how the steering practices of the coffee ecosystems, offered by agroecology, have favored a pluralist organization of values and unlocked the technical system. Thus, this PhD leads to an axiological analysis of the multi-agent technologized coffee culture in the Colombian department of Quindío

Magister Scientiae Dentium - MSc(Dent)
Candida albicans is a clinical fungal isolate that is most frequently isolated from different host niches, and is implicated in the pathogenesis of several fungal infections, including oral candidiasis. The pathogenesis and antifungal resistance mechanisms of Candida species are complex and involve several pathways and genes. Oral candidiasis incidence rates are rapidly increasing, and the increase in resistance to conventional antifungals has led to the need to develop innocuous and more efficacious treatment modalities. The purpose of this study was to explore a single pot process for phytosynthesis of zinc oxide nanoparticles (GZnO NPs) and to assess their antifungal potential.

>Magister Scientiae - MSc
Nanotechnology has emerged as a promising field in the quest to address health conditions. Green nanotechnology is a fairly new branch of nanotechnology, which aims to produce and utilize nanomaterials in a way that is safe for living organisms and their environment. Plant extracts are increasingly used in the green synthesis of gold nanoparticles (AuNPs), which involves the reduction of sodium tetrachloroaurate (III) dehydrate by phytochemicals present in the plant extract. It is probable that the green synthesised AuNPs are more biocompatible than chemically synthesised AuNPs as biomolecules of plant origin are involved in the synthesis process. Therefore, this study aimed to explore various water extracts from indigenous South African plants, which included Perlagonium capitatum, Otholobium bracteolatum, Gerbera linnae, Morrella quercifolia, Searsia lucida, Phylica bubescens, Euclea racemosa, Tetragonia fruticosa, and Searsia glauca for their potential to synthesize AuNPs and to investigate their toxicity towards several microorganisms known to cause skin infections. These organisms play a significant role in delaying the healing of wounds. The antimicrobial properties of nanoparticles are increasing exploited in the production of wound treatments.

Diatoms are unicellular, eukaryotic microalgae inhabiting nearly all aquatic habitats. They are famous for their micro- and nanopatterned silicabased cell walls, which are envisioned for various technologic purposes. Within this review article, we summarize recent in vivo modifications of diatom biosilica with respect to the following questions: (i) Which metals are taken up by diatoms and eventually processed into nanoparticles (NPs)? (ii) Are these NPs toxic for the diatoms and––if so––what factors influence toxicity? (iii) What is the mechanism underlying NP synthesis and subsequent metabolism? (iv) How can the obtained materials be useful for materials science?

For this study, biocompatible silver nanoparticles (Ag-NPs) were successfully synthesized via employing an environment friendly green approach by usage of flower extract of Plumeria obtusa. For studying the attributes of synthesized Ag-NPs, techniques such as UV-vis spectroscopy, X-Ray diffractometry (XRD), transmission electron microscopy (TEM), zeta potential and dynamic light scattering (DLS) analysis were used. The characteristic surface plasmon resonance (SPR) peak of Ag-NPs was observed around 430 nm. This peak was found to be dependent on different physicochemical parameters like amount of flower extract, reaction time, temperature and pH value. The crystal structure was studied from XRD pattern which confirmed the formation of FCC lattice with a crystallite size of 20 nm and particle size of 14 nm. TEM analysis also showed that spherical Ag-NPs of mean diameter 13 nm were formed. The stability of colloidal Ag-NPs was studied using zeta potential analysis, whose value came out to be 13 nm. The synthesized Ag-NPs were used in developing a sensing mechanism for a very harmful carcinogen, hexavalent chromium (Cr6+) and the same was tested in three different aqueous mediums. The limit of detection (LoD) came out to be 95 ± 2 pM, which is lowest reported value of LoD for a biosynthesized nanomaterials and thus, can be efficiently applied in diagnosing any contamination by cancer-causing Cr6+, in drinking water or food. Further, the enhancement in anti-bacterial action of Ag-NPs over AgNO3 was also investigated, against a gram-positive bacterium, S. Aureus. The inhibition zone came out to be much wider (10.8 mm) than that of AgNO3 (7.7 mm) or plant extract (6.7 mm). Thus, the Ag NPs synthesized in this project are non-toxic, cost-efficient and can be utilized in a variety of applications like biosensing and biomedicine.

碩士
東海大學
環境科學與工程學系
105
In this study, titanium dioxide nanotube arrays (TNAs) electrode was successfully synthesized by anodic oxidation etching method. As well as the use of green synthetic technology to add reducing agent tea or coffee to reduce metal palladium from palladium chloride. Synthesis of Palladium Titanium Dioxide Nanotube Arrays (Pd/TNAs) was conducted by Microwave Hydrothermal Method after the metal palladium was reduced。 In order to identify the surface structure, the light absorption and elemental composition, TNAs and Pd/TNAs were characterized by scanning electron microscopy (SEM), ultraviolet–visible spectroscopy (UV-vis), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). On the other hand, test the photocurrent density, electron resistance, and hydroxyl radicals by I-t plot, Electrochemistry Impedance Spectroscopy (EIS), and electron paramagnetic resonance (EPR) was investigated. Four methods, Photoelectrochemical (PEC), Photocatalytic (PC), Electrochemical (EC), and Photolysis (P) were employed to test the methyl orange degradation efficiency, the total organic carbon (TOC) removal efficiency and hydrogen production efficiency. The results show that the Pd /TNAs-C performed the best efficiency. The photocurrent (4.0 mA / cm2) of Pd /TNAs-C at 1 V (vs. Ag / AgCl) was higher than that of the uncoated TNAs (1.4 mA / cm2), indicating that Pd /TNAs-C can effectively separate photogenerated electrons and holes. Pd/TNAs is a material for promising for PEC degradation of organic pollutants in wastewater.

碩士
東海大學
環境科學與工程學系
106
A green method was developed to synthesize Cu2O/TNAs for the applications of ibuprofen oxidation and hydrogen generation. Cu2O/TNAs heterojunction was synthesized through square wave voltammetry electrochemical (SWVE) deposition method by using coffee and tea as reducing agent. SEM results illustrated that the highly ordered TNAs with an average inner diameter of 100 nm. Compared with pure TNAs and Cu2O nanoparticles were successfully depositing on the interface of TNAs, the structure of sample with no significant change after Cu2O doping. XRD analyses indicated samples were dominated by anatase phase after sintering at 450°C. In addition, the characteristic peak of Cu2O was observed at 2θ = 36.52°. XPS showed that the spectra consist of two clear peaks at 932.5 eV, 952.3 eV attributing to characteristic peaks of Cu2O. Moreover, results of UV-vis diffusion reflection spectra indicated that the absorbance edge of Cu2O/TNAs extended to the visible spectrum at approximately 600 nm examined by. The bandgap reduced to 2.1 eV after Cu2O depositing, which is lower than that of TNAs. The photocurrent of Cu2O/TNAs was 2.4 times higher than that of TNAs under irradiation. The Cu2O/TNAs was applied as a working electrode in photoelectrochemical (PEC) system for ibuprofen degradation. After 60min under 100 W Hg light irradiation, ibuprofen was complete removed in the anodic chamber and the yield amount of hydrogen was 2132 μM/cm2 in the cathodic chamber after 4 h reaction time.

No
Nanotechnology can offer new opportunities in the fight against infection. The aim of current work was to investigate an eco-friendly method for synthesis of silver nanoparticles (AgNP) which have the ability to load lipophilic compounds onto their surface. Pharmaceutically acceptable hydrophilic lipid (Gelucire® 50/13) has been used as a reducing agent for in situ reduction of silver nitrate so as to obtain silver nanoparticles. Propolis is used as model molecule for loading onto surface of AgNP owing to its well reported broad range of pharmacological activities including anti-inflammatory, antioxidant and antimicrobial activity. Propolis loaded silver nanoparticles (PLSN) were prepared and characterized for silver content, surface plasmon resonance, particle size, XRD, FTIR, TEM, antibacterial activity and burn wound healing in wistar rats. Propolis constituents were successfully loaded onto surface of AgNP using the proposed conceptual method. The formation of PLSN having size 24.3 ± 2.5 nm was confirmed using surface plasmon resonance, FTIR, XRD and TEM. The combination of propolis with AgNP significantly reduced minimum inhibitory concentration of AgNP alone when tested against Staphylococcus aureus. PLSN gel showed comparable burn wound healing in wistar rats when tested against marketed silver sulfadiazine gel. The use of Gelucire® as solubilizing agent for lipophillic drugs was effectively utilized for loading lipophillic constituents of propolis onto the AgNP. This potentially provides an effective method for the green synthesis of AgNP which can be used to load lipophillic molecules onto their surface whenever such combination is required.

碩士
東海大學
環境科學與工程學系
105
The silver nanoparticles were successfully doped on a titanium dioxide nanotube arrays (TNAs) by green synthesis. Tea and coffee extract were used as reducing agent in green synthesis, and the synthesized photocatalysts were denoted as Ag/ TNAs-t and Ag/TNAs-c, respectively. The synthesized Ag/TNAs were used as electrodes in photoelectrochemical (PEC) systems to degrade ibuprofen and produce hydrogen in the anode and cathode, respectively. Ag/TNAs-t and Ag/TNAs-c showed that silver nanoparticles were successfully deposited on titanium dioxide nanotube arrays with a diameter of about 10 nm observed by scanning electron microscope (SEM). The results of XPS showed that the amount of silver contained in Ag/TNAs-t and Ag/TNAs-c were 1.7% and 1.6%, respectively. Similar results were obtained with EDX, confirming that silver nanoparticles were successfully deposited on the surface of TNAs. The bandgap energy of Ag/TNAs-t and Ag/TNAs-c decreased from 3.2 eV to 2.7-2.8 eV after doping silver nanoparticles. In the photoelectric current measurement, Ag/TNAs-t and Ag/TNAs-c showed the photogenerated current of 2.29 and 2.50 mA/ cm2, respectively, which was 1.45 mA /cm2 higher than that of TNAs. The degradation rates of Ag/TNAs-t by electrochemical (EC), light (P), photocatalysis (PC) and photoelectrochemical (PEC) were 0.004 min-1, 0.0148 min-1, 0.0950 min-1, and 0.2132 min-1, respectively. On the other hand, the degradation rates of Ag/TNAs-c were 0.0022 min-1, 0.0639 min-1, 0.0937 min-1 and 0.2180 min-1, respectively. The results showed that the highest degradation performance were achieved in photoelectrochemical system.

碩士
東海大學
環境科學與工程學系
107
This study employed Cuprous Oxide Coated Titanium Nanotube Arrays (Cu2O/TNAs) for Photoelectrochemical degradation of the Pharmaceuticals and Personal Care Products(PPCPs) ibuprofen(IBU), diclofenac(DLC) and sulfamethoxazole(SMX). Cu2O/TNAs were green synthesized by square wave voltammetry electrochemical deposition method (SWVE). Cu2O/TNAs produced the OH radical, which could in turn oxidize pollutants effectively. Photoelectrochemical (PEC) system combined photocatalysis and electrochemical, could overcome the recombination electron-hole pair. SEM images illustrated that the diameter and the length of the Cu2O/TNAs was approximately 100 nm and 1.4 μm, respectively. The absorption wavelength of TNAs red shifted to 537 nm after Cu2O coating. The photocurrent of Cu2O/TNAs (3.87 mA/cm2) was higher than that of TNAs (1.73 mA/cm2). XRD analysis showed that the Cu2O/TNAs was dominated by anatase phase after sintering at 430℃. Results of XPS indicated that the Cu2O was successfully coated on TNAs. The EIS and Bode plot revealed that the estimated electron lifetimes, τt, of TNAs and Cu2O/TNAs were 57.6979 and 92.1596 ms, respectively. The complete removal of ibuprofen, diclofenac and sulfamethoxazole after 4 h reaction time was observed at 0.5, 0.25 and 0.25 h, respectively, under 100 W Hg light illumination at 1 V(v.s AgCl) bias potential. The TOC removal rated of ibuprofen, diclofenac and sulfamethoxazole were 42, 49 and 51％, respectively, by employed Cu2O/TNAs PEC system. The amount of hydrogen yield was 1241.7, 1159.68 and 1295.09 μM/cm2 for ibuprofen, diclofenac and sulfamethoxazole. LC/MS analysis the pathways by which Cu2O/TNAs removed ibuprofen, diclofenac and sulfamethoxazole. The chemical structures of transformation products were proposed based on using liquid chromatography mass spectrometry (LC/MS). By-products and possible degradation pathways of ibuprofen, diclofenac and sulfamethoxazole were proposed in this study.

Metal-based nanomaterials have great potential in biomedical applications due to their physiologic functions and physicochemical properties, favoring biological interactions. Magnesium is abundant in the body, mainly stored in bone, and plays a role in bone cell activities, being essential for normal bone metabolism and remodeling. Accordingly, magnesium-based materials are promising for bone-related applications. Mg(OH)2 nanoparticles appear to exert beneficial effects in bone regeneration strategies, but cellular and molecular mechanisms are poorly investigated. Upon contact with the bone, materials should allow the osteoclast-osteoblast cooperation for a normal process of bone formation and remodeling. Thus, co-culture models of osteoclastic and osteoblastic cells, allowing reciprocal communication, better mimic in vivo conditions. This work aimed two objectives. First, to establish a reproducible co-culture model of osteoblastic and osteoclastic cells, easy to implement, to provide integrated information regarding the cell response to the nanoparticles. Second, to evaluate the bone cell response to Mg(OH)2 nanoparticles in monocultured and co-cultured cells contributing to a better understanding of the involved mechanisms. MG-63 osteoblastic cell line and monocyte THP-1 cell line were selected. MG-63 cells were cultured in basal medium and osteogenic conditions. THP-1 monocytes were differentiated into macrophages with phorbol 12-myristate 13-acetate (PMA) and then into osteoclastic cells by supplementation with M-CSF and RANKL. An indirect co-culture system was set up by using Transwell® inserts to separate the cell populations. PMA-treated THP-1 monocytes were cultured on the bottom of 24-well plates, and inserts containing osteogenicinduced MG-63 cells were fitted on the well-plates. In this system, PMA-treated THP-1 cells were cultured in basal medium and with the osteoclastogenic factors. Monocultures and cocultures were maintained for 1 and 6 days, and each cell population was characterized for the respective phenotype features. Mg(OH)2 nanoparticles, synthesized in pure water or using a green synthesis process, were tested for their dose- and time-dependent effects in these culture systems. Monocultures of MG-63 cells presented high proliferation rate, synthesized ALP, expressed marker genes and were osteoblastic-induced in osteogenic conditions. Monocultured PMA-treated THP-1 macrophages differentiated into osteoclastic-like cells showed high TRAP activity, high percentage of TRAP(+) multinucleated cells and expression of marker genes. The indirect co-culture system allows the same pattern of behavior compared to the respective monocultures. However, MG-63 cells co-cultured with osteoclastdifferentiated THP-1 cells presented significantly increased ALP activity. Also, co-culture with MG-63 cells induced TRAP activity in PMA-treated THP-1 cells kept in basal medium. This shows that the cells’ reciprocal interactions have a significant effect in their phenotype behavior. Mg(OH)2 nanoparticles increased ALP of MG-63 cells, but with significantly higher induction in co-cultured cells. Nanoparticles also induced TRAP activity in THP-1 cells but, in co-cultured conditions, this effect was slightly lower than that observed in THP-1 cells supplemented with M-CSF and RANKL. These observations highlight the relevance of the cell culture model in nanoparticles testing. Summarizing, in a culture model that allows reciprocal cell paracrine interactions, Mg(OH)2 nanoparticles elicited higher inductive effect in osteoblastic behavior compared to that induced in osteoclastic behavior, suggesting an overall effect that favors osteoblastic activity.
Os nanomateriais metálicos têm enorme potencial em aplicações biomédicas devido às suas funções fisiológicas e propriedades físico-químicas, que favorecem as interações biológicas. O magnésio é abundante no organismo, está armazenado nos ossos, e desempenha um papel relevante no metabolismo e remodelação óssea. Consequentemente, os materiais à base de magnésio são promissores para aplicação óssea. As nanopartículas de Mg(OH)2 parecem exercer efeitos benéficos a nível ósseo, mas os mecanismos envolvidos têm sido pouco estudados. Após implantação, os materiais devem permitir as interações celulares garantindo a normalidade do metabolismo ósseo. Assim, os modelos de co-cultura de células osteoclásticas e osteoblásticas, que permitem uma comunicação recíproca, mimetizam as condições in vivo. Este trabalho visou dois objetivos. Primeiro, estabelecer um modelo reprodutível de co-cultura de células osteoblásticas e osteoclásticas, fácil de implementar, permitindo informação integrada sobre a resposta celular às nanopartículas. Segundo, avaliar a resposta das células ósseas às nanopartículas de Mg(OH)2 em células em monocultura e co-cultura, contribuindo para uma melhor compreensão dos mecanismos envolvidos. A linha celular MG-63 foi cultivada em meio basal e osteogénico. As células monocíticas THP-1 foram diferenciadas em macrófagos com forbol 12-miristato 13-acetate (PMA) e, depois, em células osteoclásticas por suplementação com M-CSF e RANKL. O sistema de co-cultura indireta foi implementado utilizando insertos Transwell® para separar as populações celulares. As células THP-1 foram semeadas em placas de 24 poços e diferenciadas em macrófagos, adicionando seguidamente os insertos previamente cultivados com células MG-63 induzidas em meio osteogénico. As células THP-1 foram cultivadas em meio basal ou com os fatores osteoclastogénicos. As culturas foram mantidas durante 1 e 6 dias e as populações celulares caracterizadas fenotipicamente. As nanopartículas de Mg(OH)2, sintetizadas em água pura ou por um processo de síntese verde, foram testadas nestes sistemas de cultura. As células MG-63 apresentaram uma elevada taxa de proliferação, síntese da ALP e expressão de genes específicos, parâmetros que foram induzidos em condições osteogénicas. Os macrófagos THP-1 diferenciados em células osteoclásticas mostraram elevada atividade da TRAP, células multinucleadas TRAP(+) e expressão de genes específicos. A co-cultura permitiu o mesmo padrão de comportamento comparando com as respetivas monoculturas. No entanto, as células MG-63 co-cultivadas com células THP-1 diferenciadas em osteoclastos apresentaram um aumento significativo da atividade da ALP. Além disso, a co-cultura com células MG-63 induziu a atividade da TRAP em células THP-1 mantidas em meio basal. Assim, as interações recíprocas tiveram um efeito significativo no comportamento fenotípico. As nanopartículas de Mg(OH)2 induziram a atividade de ALP das células MG-63, mas o efeito foi significativamente maior nas células co-cultivadas. As nanopartículas também induziram a atividade da TRAP em células THP-1 mas, em condições de co-cultura, este efeito foi ligeiramente inferior ao observado em células THP-1 suplementadas com M-CSF e RANKL. Estas observações realçam a relevância do modelo de cultura na avaliação das nanopartículas. Resumindo, num modelo de co-cultura que permite interações parácrinas celulares, as nanopartículas de Mg(OH)2 provocaram um maior efeito indutivo no comportamento osteoblástico em comparação com o induzido no comportamento osteoclástico, sugerindo um efeito global que favorece a atividade osteoblástica.
Dissertação de Mestrado em Biotecnologia para as Ciências da Saúde

UV radiations are the main etiological factor that contributes to the induction of skin carcinoma. The incidence of skin carcinoma is increasing at an alarming rate both in the Indian and worldwide scenario. Due to the ignorance and socioeconomic conditions, most of the non-melanoma skin cancer (NMSC) cases are not registered in the national and state cancer registry. Therefore, development of new therapeutics having higher efficacy along with skin regenerative properties is one of the important issues in today’s rapid and progressive world. In this study, novel and economic resources were selected for developing patient-friendly non-toxic therapeutics against skin carcinoma. Four chitosan formulations were prepared using silver nanoparticles (AgNPs) synthesized through biological routes and silk sericin protein. Similarly, four ethosomal formulations were prepared by encapsulating the previously prepared chitosan formulations to overcome the barrier function provided by the stratum corneum. The prepared formulations were characterized through high throughput techniques such as DLS, FE-SEM, TEM, ATR-FT-IR, and XRD. The hemolysis and hemagglutination assays proved the hemocompatibility of the prepared formulations upon incubation with RBCs. The MTT assay on A431 skin carcinoma and normal HaCaT cells showed their dose-dependent cytotoxicity. DCFH-DA, Rhodamine 123 staining provided an insight into the in vitro ROS production and mitochondrial membrane depolarizing capabilities of the prepared formulations. The morphological changes in the cell membrane, depolarization of mitochondrial membrane potential, DNA fragmentation, and annexin V-FITC staining confirms apoptosis being the primary cause of death in the chitosan and ethosomes treated samples. The time-dependent increase in intracellular production of superoxide and nitric oxide radicals confirmed that ROS are the primary source for triggering the cascade for the destruction of the cancer cells. The in vivo immune response studies in mice model showed the triggering of T cell markers in response to the exposure of prepared chitosan and ethosomal formulation.

碩士
南華大學
非營利事業管理研究所
97
September 21ST 1999, the earthquake caused houses and buildings collapsed. It not only changed the terrain and landforms, but also woke up the bright side of humanity. The victims in this calamity were forced to suffer the separation of their family and friends. Then, Puli Township Office made a deal with YWCA and Citibank of Taiwan to donate one-day salary of all their employers. With the donation, the Village of Bodhi and Evergreen, a community of 76 combined-houses, was constructed. The village received great help from Master Ii-ton, Miss Fon- tzu Chen (the current Village head), Mr. Tsu-HUA Wang (husband of Miss Chen), the government,the organizations of academic,and volunteers from Nonprofit Organization (NPO). 　 　This study uses qualitative research, documentary analysis and field study with visiting elders lived in the village. Combined with all analysis, assortments, compared with related data and SWOT analysis, we have the following findings:Compared with the features and caring system of Chang Gung Health and Culture Village and Japanese cases, it affirms the role and the importance of The Association of Serving the Elderly of Nantou County. However, the conduct of the organization is often against the laws and decrees of the society and the resource is not efficiently. 　 　We suggest that: the government has to revise or amend inappropriate laws and regulations and set a panel to work with the academic institute. The association should coordinate with the Central Government and Local Government to make all the resource efficient, combine the village with tourism and care system, and set up a new model of elder-care.

碩士
東海大學
化學工程與材料工程學系
108
In recent years, metallic nanoparticles have been widely studied and applied in various fields, but these nano materials are usually synthesied with highly toxic chemicals. Thus, the development of a cost-effective and environmentally friendly synthesis method has gradually being valued. Therefore, this study used five natural plants with good antioxidant capacity as experimental materials, including three kinds of food waste (avocado seeds, onion peel, lemon peel) and two easily available ingredients (Green tea, mung beans). Natural plant extracts are used as reducing agent to simply synthesize gold nanoparticles (AuNPs) at room temperature. 1. After the process adjustment, it is found that the onion peel extract can obtain nanoparticles with the most stable and best SERS effect, and because the plant extract contains nature stabilizing components, which increased the stability and prolonged the storage of particles. 2. The gold nanoparticles synthesized by the onion peel extract are used as a substrate for Surface-enhanced Raman Spectroscopy (SERS) which enables to detect DTNB, 4-MBA, and R6G molecules at the concentrations as low as 10-16 M; at the same time, the spectra signals of remaining pesticide on the apple peels can be measured. 3. Testing of standard and clinical microbial strains, the SERS measurement combination with principal component analysis (PCA) can be used to analyze infected microorganisms more quickly and accurately. 4. Other applications of green sybthesized gold nanoparticles, such as synergistic effect on antibiotic-antibacterial properties and cytotoxicity test, have achieved nice results, and confirmed the biocompatibility of the green synthetic gold nanoparticles. 5. The above experiments confirmed that the onion peel synthetic gold nanoparticles do have the advantages of low cost, stability, environmental friendliness and non-toxicity. For comparisions, chemical synthesis particles were prepared by using L-Ascorbic acidand the SERS ehancebility of particles were measured. The results found that the green synthesis particles showed silmilar SERS enhancebility to the chemical synthetic particles in terms of applicability, but the storage stability and non-toxicity were good in all green synthetic particles groups when compared with the chemical synthetic particles group. This study demonstrates that the green synthetic gold nanoparticle can provide a relatively low or non-toxic and prolonge storageperiod upto 7 weeks. The synthetic method is an ecologically and environmental-friendly manufacturing method, and therefore green synthesized nanoparticles may suitable for food, cosmetics, biomedical engineering, biotechnology and many other fields.

In this work, one long-chain ionic liquid (IL), 1-octyl-3-methylimidazolium chloride, was used as a template for the preparation of mesoporous silica via a modified sol-gel route. The morphology of the obtained material was characterized by scanning electron microscopy (SEM). The various vibrational modes of different functional groups in the mesoporous silica materials were revealed by Fourier transform infrared (FTIR) spectroscopy. N2 adsorption-desorption isotherms measurement was used to characterize the pore diameter and BET surface area. The adsorption capacity of malachite green dye from aqueous solution has been performed using the mesoporous silica synthesized in ionic liquid. The adsorption equilibrium of dye on mesoporous silica was found to be at 150 min. The maximum malachite green dye adsorption was found to be 97 %.

M.Sc.(Nanoscience)
The synthesis and application of gold nanoparticles (AuNPs) has been intensively studied worldwide. However, the toxicity of these nanoparticles is still a concern. We considered that various physiochemical methods used to synthesize AuNPs are energy driven, costly and require the use of harmful chemicals. Thus, this makes them not environmentally-friendly. The aim of this study was therefore to synthesize AuNPs via a greener route using Aspalathus linearis tea leaves. The AuNPs were used to coat eight commercial antifungal discs (i.e. amphotericin B, fluconazole, clotrimazole, econazole, flucytosine, ketoconazole, miconazole and nystatin) against four Aspergillus spp. for enhanced antifungal activity. The aqueous extract of A. linearis was characterized by high performance liquid chromatography and liquid chromatography–mass spectroscopy. The AuNPs were characterized using ultravioletvisible (UV-vis) spectroscopy, dynamic light scattering, nanoparticle tracking analysis, Fourier transforms infrared spectroscopy (FTIR), high-resolution transmission electron microscopy and X-ray diffraction. The toxicity of the synthesized AuNPs was studied by 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay and xCELLigence test on HepG-2 cell lines and results revealed very little to no toxicity of the AuNPs. The pristine antifungal and AuNPs coated antifungal discs were characterized by FTIR, scanning electron microscopy (SEM) and antifungal activity performed using the disc diffusion method. A strong resonance peak was observed at 529 nm of the AuNPs measured using UV-vis spectroscopy. Average size of AuNPs was ~44±1 nm and demonstrated excellent in-vitro stability under various solutions (5% NaCl, phosphate buffered saline) at varying pH levels. The SEM images revealed that the AuNPs were attached onto the coated antifungal discs when compared with the pristine antifungal discs. Antifungal results indicated that AuNPs significantly (p<0.001) enhanced the antifungal activity of the coated antifungal discs against the tested fungi when compared to the pristine antifungal discs. The AuNPs coated econazole disc exhibited the greatest (broad spectrum) activity than other antifungal agents tested. In conclusion, A. linearis can be used as a reducing agent in the synthesis of stable AuNPs. Furthermore, the AuNPs coated antifungal discs demonstrated considerable antifungal activity over the pristine antifungal discs...

博士
國立中興大學
化學工程學系所
103
In an effort to develop green processes to produce elastomeric polyurethane-urea Elastomer (PUaE) through non-isocyanate routes (NIR), highly practical methods of utilizing diphenyl carbonate (DPC) instead of diisocyanate as the carbonylation agents have been developed. The trans-esterification of several representative aliphatic diamines with DPC under different combinations and solvents has resulted in new processes which produced segmented PUaEs with consistent high molecular weights and mechanical performances. In the evolution of our NIR process developments, it began with the preparation and isolation of pure bis-carbamates from diamines such methylene dianiline (MDA) or 1,6-hexamethylene diamine (HDA) with DPC which was followed by trans-esterifications with long-chained and short-chained diamines carried out in tetramethylene sulfone (TMS) solution leading to PUaEs. Then, in the subsequent improvement, a one-pot sequential addition of three different diamines, HDA, polypropylene ether diamine of 2,000 molecular weight, and isophorone diamine were added to DPC sequentially in TMS to form the second generation PUaEs. Finally, non-VOC solvent trans-esterification processes were developed simply using the pure DPC under its molten state. The key to the present successful development lies in the realization of timing and sequence of the diamine additions to form initial biscarbamate intermediates in-situ and then in shifting the equilibrium towards polyurea product formation by phenol removal from the solution so that high molecular weight polyurea could be formed favorably. Furthermore extension of the approach through replacing partial hard segment with water dispersants groups such as ESA (3-[(2-aminoethyl) amino]-1-propane sulfonic acid sodium salt) or APTES ((3-Aminopropyl) triethoxysilane) in making water-based PUaE also have been achieved. The optimized NIR polyurea films made in this study consistently have the ηinh of over 0.6, with high performance characteristics showing tensile strength ranges of 15~30 MPa and elongation exceeding 400 %. Ultra-high molecular weight of polyurea (NS-P7) and the highest heat properties with Td of > 315 ℃ was achieved in the melt-process. Well-defined soft- and hard-segment domains were observed for the products as determined by AFM. These new improved NIR processes to produce segmented poly-aliphatic ureas thereby comply fully with the principles of green chemistry using safe and readily available chemicals.