Yes / In this study, we applied different sizes of gold nanoparticles (Au-NPs) to isoproterenol (ISO)-induced hyperthyroid heart disease rats (HHD rats). Single dose of 5, 40, 100 nm Au-NPs were injected intravenously. Cardiac safety tests were evaluated by cardiac marker enzymes in serum and cardiac accumulation of Au-NPs were measured by ICP-MS. Our results showed that size-dependent cardiac effects of Au-NPs in ISO-induced hyperthyroid rats. 5 nm Au-NPs had some cardiac protective effect but little accumulation in heart, probably due to smaller size Au-NPs can adapt to whole body easily in vivo. Histological analysis and TUNEL staining showed that Au-NPs can induce pathological alterations including cardiac fibrosis, apoptosis in control groups, however they can protect HHD groups from these harmful effects. Furthermore, transmission electron microscopy and western blotting employed on H9C2 cells showed that autophagy presented in Au-NPs treated cells and that Au-NPs can decrease LC3 II turning to LC3 I and decrease APG7 and caspase 12 in the process in HHD groups, while opposite effects on control groups were presented, which could be an adaptive inflammation reacts. As there are few animal studies about using nanoparticles in the treatment of heart disease, our in vivo and in vitro studies would provide valuable information before they can be considered for clinical use in general.

This thesis summarizes the methods of preparation and optical properties of hybrid assemblies of Au NPs and cadmium selenide (CdSe) QDs. First chap-ter deals with the literature survey and theoretical aspects of plasmonics and discussions on optical excitations of metal (plasmons) and semiconducting QDs (excitons). Variation of energy levels of CdSe QDs and its optical properties i e. absorption and emission properties under strong confinement regime have been discussed with respect to effective mass approximation (EMA) model. This is followed by the discussion on optical properties of Au NPs and rods, describing absorption properties, based on Mie theory. Size and shape depen-dent variation of absorption properties. Theoretical discussions of collective effects in QDs assemblies and plasmonic interactions with the QDs assemblies i.e. plasmonic Dicke effect and metal nanoantenna interaction with CdSe QDs arrays is provided. In the second chapter a discussion on experimental techniques used for the study is provided. It starts with a discussion on the synthesis methods for CdSe QDs and Au NPs/rods with different capping ligands. Different techniques of preparation of CdSe QDs assemblies and their hybrid with metallic nanoparti-cles has been discussed. Further discussion on optical microscopy techniques, confocal, near field scanning microscopy (NSOM), Brewster angle microscopy and electron microscopy techniques i. e transmission electron microscopy and scanning electron microscopy and thermogravimetry analysis of the samples is provided. In the third chapter the details of the different self-assembly methods of preparation of hybrid assemblies of CdSe QDs and Au NPs /rods are given. The different strategies are used for different type of hybrids. In first method of Langmuir-Blodgett (LB) , effect of different capping agents, core size, and number ratios of Au NPs/rods to CdSe QDs, effect of anisotropy of Au NPs on the LB films of CdSe QDs assemblies is discussed. In another method of dip coating several control parameters like dip time, concentration of the solution and dip speed of transferring an aligned GNRs is given. Finally a combination of LB and dip coating methods is described for transferring aligned GNRs over a compact layer of CdSe QDs. At the end, a section is devoted to hit and trials of self-assemblies of hybrid of GNRs and CdSe QDs using LB method, the failures of which resulted in devising a method which uses a combination of LB and dip coating. In fourth chapter effects of plasmons on the collective emission of CdSe QDs assemblies are investigated. A plasmonic tuning of photoluminescence from semiconducting QD assemblies using Au NP in different ratio and different packing density has been discussed. We have described how the emission from a closed pack assemblies, prepared with different packing densities depends on the packing density and extent of spectral overlap between QD photolumi-nescence and the metal nanoparticle absorbance. We have provided possible evidence for plasmon mediated coherent emission enhancement from some of these assemblies from the case of strong spectral overlap between CdSe QDs and Au nanoparticle. In fifth chapter, we have demonstrated non local far field enhancement of PL in QDs assemblies induced by isolated and partially aligned GNRs nano-antenna located on such assemblies. It is shown that the emission is also anisotropic with the maxima being near such GNRs assembly which decays to finite, nonzero and significantly large values even away from the vicinity of any such assemblies. For this novel effect it is shown to have a clear spec-tral dependence. It is shown to be maximum when the longitudinal surface plasmon resonance absorption maxima is resonant with the CdSe QD photolu-minescence maxima and the excitation wavelength and is always non-existent for the off resonant case. We have also shown that finite difference time do-main simulations could model some of the observed near field effects but the far field effects could not be modelled in such simulations.

Nanoelectrochemistry explores the differences in chemical behaviour at the nanoscale as compared to the macro-scale. This thesis is concerned with nanoelectrochemistry and aims to develop and apply novel experiments for the unambiguous identification of changed electrode kinetics at the nanoscale. This is challenging since electrochemical responses are controlled by diverse factors like enhanced mass transport and adsorption as well as electron transfer kinetics. A joint computational and experimental strategy is employed. Chapter 1, 2 and 3 cover essential introductory material and basic experimental details relevant to all experiment. Fuller descriptions and details are given in the following chapters as and when needed. Chapter 4 reports the development of an electrochemical characterization method, to achieve a fast and simple quantification of the average particle size and the number of nanoparticles deposited on a glassy carbon electrode. The method consists of surface area characterization by underpotential deposition of lead particles and the determination of the amount of gold from anodic stripping in HCl. This method is also proven to be effective by comparing the results with SEM measurements. Next, in chapter 5, a generic strategy combining computation and experimental approach is developed in order to study the electron transfer kinetics of gold nanoparticles. The modelling part considers the kinetics of the electrochemical process on the bulk materials for different regions in the electrode, that is, the substrate (glassy carbon) and the nanoparticles (gold). Comparison of experimental and theoretical results enables the detection of changes in the electrode kinetics at the nanoscale. This approach is applied into the electro-oxidations of nitrite and L-ascorbic acid for gold nanoparticles from 20 - 90 nm. In the former, analysing the system shows that no change in electron transfer kinetics is involved in the process, even though a decrease of the over-potential and an increase in the peak current are observed. But these changes reflect mass transport effects, not electrocatalysis. A case where an authentic enhanced electron transfer kinetic change occurs is shown for the ascorbic acid system. Finally, in chapter 6 , the above strategy is exploited further to apply a quantitative study of electron transfer kinetics for various sizes of gold nanoparticles in the oxygen reduction reaction system in sulphuric acid at 298 K. The latter is at the heart of energy transformation techniques (fuel cells, battery and so on). Compared with the electron transfer kinetics on macro gold electrodes, there is no change at gold nanoparticles from size 5 nm to 40 nm. However, in the presence of Pb(II), a strong enhancement of electron transfer kinetics is observed on 5 nm citrate capped gold nanoparticles for ORR. On the other hand, a significant decrease of electron transfer kinetics has been found for gold nanoparticles of size 2 nm for ORR. The latter observation of strong negative electrocatalysis is also observed for the hydrogen evolution reaction (HER). This represents the first report of such effects with the HER system. Overall the thesis has established a rigurous, theoretical basis for evaluating electrocatalysis in nanoparticulate system.

En 1971, Le Dr. Américain Judah Folkman a publié une hypothèse selon laquelle la croissance tumorale dépendait de l'angiogenèse. Le défit des recherches actuelles est de trouver un moyen pour affamer la tumeur en inhibant son angiogenèse. L'angiogenèse est un processus physiologique complexe qui fait intervenir de nombreux récepteurs, parmi lesquels se trouve le récepteur du mannose-6-phosphate / Insulin-like growth factor II (RM6P/IGFII). Le but de ce travail a donc consisté en la synthèse de nano-objets mannosylés et de nouveaux analogues du Mannose-6-Phosphate (M6P) puis en l'évaluation de leur activité angiogénique par la méthode de la « CAM » sur des embryons de poulet et dans le modèle des explants d'aorte de rat. Dans un premier temps des nanoparticules d'or ont été préparées, fonctionnalisées avec les dérivés du M6P ayant montré des résultats intéressants au cours de travaux antérieurs réalisés au sein du laboratoire. Par la suite des analogues originaux tels que un borate, un acide boronique, un pyrophosphate, un pyrophosphonate ainsi que l'analogue rétroisotère du M6P ont été synthétisés. D'autre part, il a été montré que le RM6P/IGFII pouvait lier deux molécules de M6P ou une molécule d'oligosaccharide diphosphorylée par monomère. De ce fait, des molécules bidentées, des composés de type bolaforme et des trisaccharides difonctionnalisés ont été élaborés puis leur activité biologique a été valuée. / In 1971, the American Dr. Judah Folkman published the hypothesis : tumor growth depends on angiogenesis. The challenge of current research is to find a way to starve tumors by inhibiting angiogenesis. Angiogenesis is a complex physiological process that involves many receptors, among which is the receptor for mannose-6-phosphate / Insulin-like growth factor II (RM6P/IGF-II). The aim of this work was the synthesis of mannosyl nano-devices and new analogues of Mannose-6-Phosphate (M6P). Evaluation of their angiogenic activity was made by the 'CAM essay' on embryo of chicken and in the model of the explantations of rat's aorta. First, gold nanoparticles functionnalized with M6P analogues were prepared. Those analogues have been chosen among the most interesting candidates as described previously in our laboratory. Secondly, original analogues such as a borate, a boronic acid, a pyrophosphate, a pyrophosphonate as well as the retroisotere analogue of the M6P were synthetized. The RM6P/IGFII can bind two molecules of M6P or a diphosphoryled oligosaccharide molecule by monomer (receptor). Therefore, bidentate molecules, difunctionnalized bolaform compounds and difunctionnalized trisaccharides were synthesized and their biological activity evaluated.

Tungsten oxide (WO3) is a semiconducting transition metal oxide with interesting electronic, structural, and chemical properties that have been exploited in applications including catalysis, gas sensing, electrochromic displays, and solar energy conversion. Nanocrystalline WO3 can absorb visible light to catalyze heterogeneous photooxidation reactions. Also, the acidity of the WO3 surface makes this oxide a good thermal catalyst in the dehydration of alcohols to various industrially relevant chemicals. This dissertation explores the photocatalytic and thermal catalytic reactivity of nanocrystalline porous WO3 microparticles. Furthermore, investigations into the changes in WO3 reactivity are carried out after modifying the porous WO3 particles with gold nanoparticles (Au NPs). On their own, Au NPs are an important class of materials that have had a large impact in many fields such as catalysis, biomedical imaging, and drug delivery. When combined with WO3, however, their influence as part of a composite Au/WO3 catalyst has not been widely studied. Porous WO3 microparticles were first prepared using mesoporous silica (SiO2) spheres as hard templates and the physical properties of these materials were fully characterized. A facile sonochemical method was used to deposit Au NPs on the WO3 surface. Using methylene blue (MB) as a photocatalytic probe, the reaction products and the catalytic activity of WO3 and Au/WO3 catalysts were compared. Composite Au/WO3 photocatalysts exhibited significantly greater rates of MB degradation compared to pure WO3. Interestingly, the observed mechanism of MB degradation was not vastly different between the two types of catalysts. The gas-phase photocatalytic oxidation of methanol (MeOH) was studied to further understand the role of WO3 and Au NPs in these photocatalysts. Porous WO3 showed greater photooxidation rates compared to bulk WO3 because of its increased active surface area. Pure WO3 and Au NPs on porous SiO2 (SiO2-Au) were both active MeOH photooxidation catalysts and were highly selective to formaldehyde (HCHO) and methyl formate (MF), respectively. Two different mechanisms, namely band gap excitation of WO3 and surface plasmon resonance (SPR) on Au NPs, were responsible for this result. Again, the Au/WO3 composite catalysts showed greater photocatalytic activity than WO3, which increased with Au loading. This high activity led to the complete photooxidation of MeOH to carbon dioxide (CO2) over Au/WO3 catalysts. Finally, the thermal catalytic transformation of MeOH under aerobic conditions was carried out to further characterize the acid and redox active sites of WO3 and Au/WO3 catalysts. Pure WO3 was highly selective for MeOH dehydration to dimethyl ether (DME), whereas Au/WO3 showed increased oxidation selectivity to products such as HCHO, FM, and COx. The Au NPs increased the reducibility of the WO3 species, which made surface oxygen atoms more labile and reactive towards MeOH. Also, the WO3 facilitated the formation of cationic Au (Au δ+) species. This combination of effects created through a strong Au/WO3 interaction increased the activity of WO3 species, but it decreased the activity of the Au NPs.

This Thesis reports the synthesis, purification and characterisation of gold nanoparticles (NPs) functionalised with a monolayer of hydrazone ligands in order to perform post-synthetic manipulations of the NP-bound monolayer exploiting dynamic covalent chemistry. NP post-synthetic manipulation based on reversible non-covalent interactions between oligonucleotides represents a promising approach to achieve functionalisation and self-assembly for potential applications in biology and medicine. However, the stability of these nanosystems is ensured only in a narrow window of environmental conditions. On the other hand, irreversible covalent strategies potentially allow the full range of synthetic chemistry to be exploited but they provide poor control over the manipulation of the NP-bound monolayer and can only produce kinetically controlled amorphous NP aggregates. Dynamic covalent chemistry represents an interesting and an attractive alternative approach because it would combine the reversibility of non-covalent interactions with the stability of covalent bonds. By this way, ligand-functionalised NPs could be manipulated in order to introduce a large variety of molecular functionalities on the NP surface not only to subtly tune the NP physicochemical properties but also to access an entire range of novel nanomaterials.

Cette thèse comporte trois parties principales : la première concerne la synthèse et la fonctionnalisation des nanoparticules (NPs) d’or de forme sphérique et cylindrique. Les NPs d’or sont obtenues par réduction d’un sel métallique. En faisant varier certains paramètres de synthèse tels que la concentration en sels et/ou la concentration en réducteur, on peut facilement ajuster la taille de NPs sphériques. Bien qu’il existe diverses méthodes permettant de préparer des NPs cylindriques, il subsiste un problème de reproductibilité basée sur la pureté des produits de synthèse. Les différentes analyses de CTAB nous ont permis de proposer des solutions à ce problème. La fonctionnalisation de la surface des NPs d’or permet d’apporter à ces dernières de nouvelles propriétés tout en conservant leurs propriétés intrinsèques. Le but de cette fonctionnalisation est de modifier la surface des NPs en fonction des applications visées. Nous présentons ainsi différentes études de fonctionnalisation par des polyélectrolytes (PEI et PSS), des couches oxydes de SiO2, et de TiO2 et par le TDBC. La réponse optique des NPs d’or étant sensible à l’indice de réfraction du milieu environnant, il est possible de suivre et de quantifier cette fonctionnalisation par spectroscopie d’absorption. Dans une seconde partie, nous avons développé une voie de synthèse simple permettant de préparer le cœur coquille Au@TDBC sans ajout supplémentaire de sels ou de bases et à température ambiante. Etant donné qu’il est possible de moduler la taille des particules, l’optimisation du couplage fort entre les transitions électroniques du TDBC et les modes plasmon de résonances des Nps d’Au a été obtenu correspondant à une énergie de Rabi de 220 meV valeur qui n’a pas encore été obtenue avec un tel système. Dans une troisième partie, nous avons développé une nouvelle approche basée sur la méthode de Stöber pour fonctionnaliser les NPs avec des couches d’oxyde de SiO2 et de TiO2. L’utilisation des systèmes Au@TiO2 est une perspective intéressante en photocatalyse car le contact entre le métal et le semi-conducteur devrait entrainer une nette augmentation de l’efficacité photocatalytique. En effet, le métal agit comme un réservoir de photoélectrons améliorant le transfert de charges interfaciales tout en retardant la recombinaison des paires électrons-trous photo excités du semi-conducteur. / This thesis has three main parts: the first part relates to the synthesis and the functionalization of spherical gold nanoparticles (NPs) and nanorods. Gold NPs are obtained by chemical reduction of gold salt. By varying some synthesis parameters such as gold salt concentration and or reducing agent concentration, we can easily adjust the size of gold NPs. Different methods can be used to prepare gold nanorods, but there is a problem of reproducibility. This problem is based on the purity of products used to prepare gold nanorods. Different analysis of CTAB allowed us to propose solutions to this problem. Functionalization brings to gold NPs new properties. The aim of the functionalization is to modify the surface of gold NPs based on the intended applications. We present various functionalization of Au NPs by polyelectrolytes (PEI and PSS), oxides (SiO2 and TiO2) and TDBC. The optical response of Au NPs is sensitive to the refractive indexe of the surrounding medium, it is then possible to monitor and quantify this functionalization by absorption spectroscopy. In the second part of this work, we have developed a simple synthetic route for preparing Au@TDBC core shell without additional salts or bases at room temperature. Since it is possible to vary the particle size, optimization of the strong coupling between the electronic transitions of TDBC and the resonance plasmon of Au Nps obtained correspond to Rabi energy of 220 meV value which has not yet been achieved with such a system. In the third part, we have developed a new approach based on the Stöber method to functionalize the NPs with an oxide layer of SiO2 and TiO2. The use of Au@TiO2 core shell system is an interesting perspective in photocatalysis because the contact between metal and semiconductor should cause a marked increase in the photocatalytic efficiency. Indeed, the metal acts as a reservoir of photoelectrons improving the interfacial charge transfer while retarding the recombination of electron-hole pair of the semiconductor.

Doctor of Philosophy / Department of Chemistry / Christine M. Aikens / Small silver and gold clusters (less than 2 nm) display a discrete absorption spectrum characteristic of molecular systems whereas larger particles display a strong, broad absorption band in the visible. The latter feature is due to the surface plasmon resonance, which is commonly explained by the collective dipolar motion of free electrons across the particle, creating charged surface states. The evolution between molecular properties and plasmon is investigated. Time-dependent density functional theory (TDDFT) calculations are performed to study the absorption spectrum of cluster-size silver and gold nanorods. The absorption spectrum of these silver nanorods exhibits high-intensity longitudinal and transverse modes (along the long and short axis of the nanorod respectively), similar to the plasmons observed experimentally for larger nanoparticles. These plasmon modes result from a constructive addition of the dipole moments of nearly degenerate single-particle excitations. The number of single-particle transitions involved increases with increasing system size, due to the growing density of states available. Gold nanorods exhibit a broader absorption spectrum than their silver counterpart due to enhanced relativistic effects, affecting the onset of the longitudinal plasmon mode. The high-energy, high-intensity beta-peak of acenes also results from a constructive addition of single-particle transitions and I show that it can be assigned to a plasmon. I also show that the plasmon modes of both acenes and metallic nanoparticles can be described with a simple configuration interaction (CI) interpretation. The evolution between molecular absorption spectrum and plasmon is also investigated by computing the density of states of spherical thiolate-protected gold clusters using a charge-perturbed particle-in-a-sphere model. The electronic structure obtained with this model gives good qualitative agreement with DFT calculations at a fraction of the cost. The progressive increase of the density of states with particle size observed is in accordance with the appearance of a plasmon peak. The optical properties of nanoparticles can be tuned by varying their composition. Therefore, the optical behavior of the bimetallic Au[subscript](25-n)Ag[subscript]n(SH)[subscript]18[superscript]- cluster for different values of n using TDDFT is analyzed. A large blue shift of the HOMO-LUMO absorption peak is observed with increasing silver content, in accordance with experimental results.

<p>I. Gallium-hemoglobin Coated Silver Nanoparticles for Antimicrobial Photodynamic Therapy Against Bacterial Pathogens One of the mechanisms for bacterial pathogens’ hemin acquisition is through cell-surface hemin receptors (CSHRs), which are responsible for rapid hemin recognition. GaPpIX, as a hemin analog, can be rapidly taken up by CSHR-expressing bacteria, such as <i>Staphylococcus aureus</i> (<i>S.aureus)</i>. Previous works shown that GaPpIX has aPDI activity at micromolar level of concentration following 10 seconds of 405-nm light exposure using LED array. The photosensitizing ability of GaPpIX can be further enhanced by incorporating with hemoglobin (GaHb) and 10 nm silver nanoparticles (AgNP). The results suggested a higher aPDI activity of GaHb-AgNP than any of its components against MRSA strains and neglectable cytotoxicity against keratinocytes. GaHb-AgNPs were also found having aPDI activity against intracellular MRSA and <i>Mycobacterium abscessus </i>but not effective against <i>S. aureus</i> biofilm. GaHb-AgNPs have no significant toxicity toward macrophages with concentrations lower than 22.64 μg/mL.</p> <p> </p> <p>II. Synthesis and Properties of Magnetic Gold Nanoparticles</p> <p> Superparamagnetic gold nanoparticles support hybrid magnetic and plasmonic properties that can be exploited for a variety of applications. In this paper we present new insights on the synthesis of magnetic gold nanoparticles (MGNPs) with an emphasis on efficiency, scalability, and waste reduction, supported by a comprehensive analysis of their physical and materials properties. Aqueous suspensions of colloidal Fe₃O₄ are conditioned with 5-kDa polyethylene glycol and L-histidine to mediate the nucleation and growth of gold by a mild reducing agent. Isotropic MGNPs on the order of 100 nm can be synthesized using scalable reaction conditions with Au:Fe mole ratios as low as 1:2 and cleansed with generally regarded as safe (GRAS) chemicals for the removal of residual iron oxide. High-resolution energy-dispersive x-ray imaging of individual MGNCs revealed these to be ultrafine composites of gold and SPIO rather than core–shell structures. The attenuated total reflectance infrared (ATR-IR) spectroscopy and Raman spectroscopy indicated that the cleansing step does change the optical properties of the synthesized MGNPs. Magnetometry of MGNCs in bulk powder form confirmed their superparamagnetic nature, with bulk moments between 6 to 7 emu/g.</p>

Esse trabalho teve como objetivo a produção e a caracterização elétrica de filmes finos de telureto com nanopartículas de ouro, depositados pela técnica sputtering, para aplicação em dispositivos de memória. Os filmes finos foram produzidos a partir de alvos cerâmicos de telureto (TeO2-ZnO) e foram nucleadas nanopartículas de ouro para observar sua influência no comportamento de memória. Foi desenvolvida metodologia adequada para a nucleação das nanopartículas por meio de tratamento térmico. Foram produzidos filmes com diferentes concentrações e tamanhos de nanopartículas e diferentes fluxos de oxigênio durante a deposição. Os filmes foram caracterizados por técnicas como Microscopia Eletrônica de Transmissão (TEM), Perfilometria, Espectrometria por Retroespalhamento de Rutherford (RBS) e extração de curvas de Corrente x Tensão (I-V). Por meio das medidas I-V foi possível identificar as melhores condições para aplicações em memória e correlacioná-las com as variáveis de processo estudadas. Resultados obtidos mostraram que a melhor condição para aplicações em memória não volátil foi encontrada em filmes com 100 nm de espessura e depositados com fluxo de oxigênio de 1 sccm, abertura do shutter em 50 e tratados termicamente por 10 ou 20 horas à 325 ºC. Nesses casos, foi observado um abrupto aumento na corrente (4 ordens de grandeza) em aproximadamente 6,5 V para 10 horas de tratamento térmico e 3,5 V para 20 horas de tratamento térmico, indicando a transição do estado inicial de baixa condutividade para outro de alta condutividade. As nanopartículas de ouro proporcionam maior capacidade de armazenamento de elétrons e não favorecem o transporte de corrente através do isolante; elas atuam como armadilhas para as cargas elétricas, o que reduz a corrente de fuga para níveis mais baixos. Foi estudada a influência do diâmetro e da concentração volumétrica das nanopartículas de ouro no valor da tensão elétrica associada à transição abrupta da corrente. Este parâmetro desempenha um papel importante no efeito de memória, pois determina a facilidade/dificuldade em se preencher e saturar as armadilhas (nanopartículas de ouro) com elétrons. Os materiais estudados neste trabalho mostraram-se promissores para aplicações em dispositivos de memória não volátil e possuem características semelhantes aos materiais orgânicos usados para o referido fim. / This work has the objective to fabricate and characterize electrically tellurite thin films containing gold nanoparticles, deposited by the sputtering technique, for application in memory devices. Thin films were produced from ceramic tellurite targets and gold nanoparticles were nucleated in order to observe their influence on memory behavior. An appropriate method was developed for the nucleation of the nanoparticles by means of heat treatment. Films with different nanoparticles sizes and concentration and different oxygen fluxes during the deposition, were produced. The films were characterized by techniques such as Transmission Electron Microscopy (TEM), Profilometry, Rutherford Backscatter Spectrometry (RBS) and current x voltage (I-V) curves. Using I-V measurements, it was possible to identify the best conditions for memory applications and correlate them with the process variables studied. The results showed that the best condition for memory applications was found in films with 100 nm thickness and deposited with oxygen flow of 1 sccm, opening shutter in 50 and heat treated for 10 or 20 hours at 325 ºC. In these cases, current abrupt increase (4 orders of magnitude) was observed at about 6.5 V for 10 hours of heat treatment and 3.5 V for 20 hours of heat treatment, indicating the transition from high impedance state to low impedance state. Gold nanoparticles provide a larger electron storage capability, and do not favor the electric transport through the insulator; they act as traps for electrical charges, which reduces the leak current to lower levels. It was studied the influence of the gold nanoparticles diameter and volumetric concentration on the voltage associated to the abrupt current. These parameters played an important role in the memory effect, as they determined the facility/difficulty to fill and saturate the traps (Au nanoparticles) with electrons. The materials studied in the present work, based on TeO2-ZnO thin films with Au nanoparticles, are promising for applications in nonvolatile memory device with similar characteristics to organic materials used for the same purpose.