16^th World Nano Conference June 05-06, 2017 Milan, Italy

Biography:

Manfred George Krukemeyer completed his study of Medicine at University of Vienna, University of Kiel and University of Bonn, Germany. He completed his Resident of Surgery in 1991. He is a board approved certified Surgeon, Emergency Medicine Physician and Nutritionist. His research focuses on Oncology, Nanomedicine and Transplantation. He has more than 50 publications.

Abstract:

Therapies of liver tumors display diverse treatment alternatives. The administration of cytostatic coupled with and without iron oxides (Fe3O4) has been presented in an experimental series with 36 animals with prior implantation of an R1H rhabdomyosarcoma in the liver, since iron undergoes selective phagocytosis in the liver. In group I, mitoxantrone is injected into the lateral tail vein of the animals (n=12) in a dosage of 1 mg/kg of body weight. Group III (n=12 animals) received mitoxantrone coupled with iron oxide (Fe3O4), and group II (n=12 animals) received NaCl, in the same dosage for all groups. In the sonography and in the measurement of the volume, a significantly smaller tumor growth is found in group II compared with group I and III. The volume was measured manually postmortally in mm3 (length x breadth x height). The tumor volume showed the lowest growth in group II, which was treated with mitoxantrone-coupled iron oxides. Three animals from group II died. The autopsy revealed no indication of the cause of death. There were neither thromboses nor allergic reactions in any of the animals. It can be clearly seen that group I has a smaller mean volume and less scatter than group II. The mean of group I is below group II.

Biography:

Claudia Cabella completed her Graduation in Chemistry and PhD in Biochemistry. Since 2001, she works at Centro Ricerche Bracco (CRB, Bracco Imaging SpA) being involved mainly in the field of Magnetic Resonance Imaging and Optical Imaging. Her main skills are preparation of cell cultures and related tumoral animal models and use of MRI and OI scanners. She worked on MRI and OI projects focused on tumoral targeting with different paramagnetic and fluorescent probes and in particular, she worked as a partner in the European research project NanoAthero on a specific task aimed at identifying blood pool agents for atherosclerotic plaque stratification.

Abstract:

Introduction: Atherosclerosis is a progressive disease characterized by accumulation of lipids and fibrous elements in the large arteries, causing the formation of atherosclerotic lesions. With the progression of the disease, plaques can become increasingly complex, showing different elements of dangerousness as thin fibrous cap, lipidic necrotic core, ulcerations at the luminal surface and haemorrhages. Currently, several imaging techniques are able to identify plaques in humans but not to clearly define composition as a predictor of an acute event, causing difficulties on the definition of a proper treatment. In particular, a diagnostic tool aimed to stratify plaques with respect to different permeability (i.e. different dangerousness) could help clinicians to predict the response to a drug-loaded nanosystem based therapy.

Aim: The aim of this study was to investigate the plaque endothelial local permeability in the ApoE-/- mouse model with optical imaging using fluorescent blood pool agents.

Methods: A human serum albumin conjugated with Cy5 (HSA-Cy5) and an albumin binder conjugated with IrDye800 (B26170) were administered to ApoE-/- mice at different weeks of feeding with high fat diet. Arterial trees were removed, imaged with a fluorescence microscope system and then histologically processed.

Results & Conclusions: Plaques developed in different districts of the arterial tree were classified through a grading index (between one and three) with respect to their morphology and displayed higher macrophage content at the early stage of development. Both the fluorescent probes showed higher permeation in early plaques than in more advanced ones, thus correlating with a high inflammatory state. The proof of concept that nano-based systems are able to probe permeability of atherosclerotic plaques, defining which ones are suitable for an anti-inflammatory therapy based on drug-loaded nanoparticles, was reached through OI and could be relatively easily translated in a clinical tool for MRI with the use of a proper Gd-based blood pool agent.

Biography:

Akbar S Khan has completed his PhD at University of Oklahoma, USA and Post-doctoral studies at University of Colorado School of Medicine at Denver, USA. He is the Senior Scientist, Program Director and Policy Advisor for a Defense Threat Reduction Agency linked with Pentagon and Office of Secretary of Defense. He has published more than 75 manuscripts in top journals including Science and Nature, six patents and has been serving as an Editorial Board Member of Journa of Microbiology and Experimentation and Global Security: Health, Science and Policy.

Abstract:

Nanotechnology is science, engineering, and technology conducted at the nanoscale, which is about 1 to 100 nanometers. All things, both living and non-living, are constructed of atoms. The nano-scale sparks so much interest because when a substance is artificially created, structured atom by atom; it can have different or enhanced properties compared with the same substance as it occurs naturally, which includes increased chemical reactivity, optical, magnetic, or electrical properties. Nanotechnologies aim to exploit these properties to create devices, systems, and structures with new characteristics and functions. For example, researchers hope to construct from the very bottom (that is to say, atom by atom) a substance as strong as diamond, but more flexible and far less expensive. It would also be possible to manufacture a substance in the shape and size needed such as a thin string as strong as steel. So far, nanotechnology is applied in various areas: Applied design a water filtration system on the nano-scale that is so efficient, it only lets water molecules through it; used to create filters and sensors to screen out toxins or adjust flavors, and packaging to sense when the food inside is spoiling and alert the customer; the ability to assemble nano-scale particles that could be targeted at certain parts of the body or certain viruses in the blood; economical solar cells to make solar power economical and diminish our dependency on coal, oil, nuclear fuel and fuel wood and; to clean up the environment. To clean up oil spills, imagine a scrubber built from tiny nanotubes that could manipulate the atoms in an oil spill to render it harmless. Just like any new technology, there are varieties of health, environmental and safety risks to this technology from free rather fixed manufactured nanoparticles. In initial studies, manufactured nanoparticles have shown toxic properties. They can enter the human body in various ways, reach vital organs via the blood stream, and possibly damage tissue. Due to their small size, the properties of nanoparticles not only differ from bulk material of the same composition but also show different interaction patterns with the human body. These promises and challenges of nanotechnology will be presented here.

Biography:

Giulio Sancini is an Assistant Professor of Human Physiology and Specialist in Applied Pharmacology. He has focused his research activity mainly on Neurosciences, Nanomedicine, and Nanotoxicology. His research has been funded by European FP7 (NAD Project, Nanoparticles for diagnosis and therapy of Alzheimer’s disease and FP6 (BONSAI project, Bio-imaging with Smart Functional Nanoparticles). He has published more than 45 papers in reputed journals and has been serving as an Editorial Board Member of repute. He is Head of the Physiology Unit in Department of Medicine and Surgery at University of Milano-Bicocca.

Abstract:

Pharmacological treatment of brain diseases is still a difficult task. Many potential therapeutic compounds fail to reach their molecular targets in the brain parenchyma limiting the development of clinically relevant therapeutics. Indeed the concentration of therapeutic compounds into the brain parenchyma depends on various factors but it is clear that the capability to cross the blood brain barrier (BBB) is of paramount importance. The difficulties encountered in the treatmen of brain disease with conventional pharmacological tools have created the need for alternative and innovative strategies. Nanotechnology-based approaches might improve the unfavorable pharmacokinetic of molecules unable to overcome the BBB. Recent applications in nanomedicine focus on nanoparticles (NP) as they are promising tools for site-specific delivery of drugs and diagnostic agents, through the possibility to functionalize their surface with target-specific ligands. Treatment options for Alzheimer’s disease (AD) are limited because of the inability of drugs to cross the BBB. Previously, we showed that intraperitoneal administration of liposomes functionalized with phosphatidic acid and an ApoE-derived peptide (mApoEPA-LIP) reduces brain beta-amyloid (Aβ) burden and ameliorates impaired memory in AD mice. Among the different administration routes, pulmonary delivery is a field of increasing interest not only for the local treatment of airway diseases but also for the systemic administration. We investigated lung administration as an alternative, non-invasive NP delivery route for reaching the brain. Our results show that mApoE-PA-LIP were able to cross the pulmonary epithelium in vitro and reach the brain following in vivo intratracheal instillations. Lung administration of mApoE-PA-LIP to AD mice significantly decreased total brain Aβ (–60%; p<0.05) compared to untreated mice. These results suggest that pulmonary administration could be exploited for brain delivery of NP designed for AD therapy.

Biography:

Isabel Montero is currently a Professor at Spanish National Research Council (CSIC), Madrid, Spain. She is the Head of Group Surface Nano-structuring for Space and Terrestrial Communications, Materials Science at Institute of Madrid (ICMM-CSIC), Madrid. She is also Director of Spanish Laboratory on secondary electron emission, CSIC.

Abstract:

The secondary electron emission yield (SEY) from materials used in vacuum in high-power RF devices in space missions is the feedback mechanism of the resonant discharge of electrons or multipactor discharge. The maximum work power of those RF systems is unavoidably limited by this effect. Here, we report low-secondary electron emission yield from mixtures of powdered graphite, graphene and carbon nanowires. The samples were tested for SEY, scanning probe microscopies and X-ray photoemission spectroscopy analysis. Insertion and reflection losses measurements of carbon nanoparticles coated RF filters are also critical measurements to analyze the influence of the anti-multipactor coating on the performance quality. Thus, while skin depth at 12 GHz for a typically used material in space borne devices like silver is around 600 nm, coatings of les than 10 nm thickness have demonstrated an improved system overall performance. This is because despite the superior coating materials’ resistivity compared to silver, with its inherent worsening on RF losses, the extremely thinness of the covering layer make that worsening almost negligible, meanwhile SEY properties clearly move on the right direction (Fig.1). The SEY experiments were performed in an UHV chamber also equipped with XPS for surface analysis. The SEY was measured over the primary electron energy range of 0 to 1000 eV. The shape of the SEY curve as a function of primary energy seems to be the inverted image of the typical universal SEY curve. The effect of point sources exhibiting low threshold electron emission due to local field enhancement at the oxidized tip emitters was reduced because the roughening the surface leads to lower secondary electron yields. It was achieved that the emitted secondary electrons are reduced to 70%.

Biography:

Tomer Zidki has completed his PhD in 2009 at Ben-Gurion University of the Negev and has his expertise in “Mechanistic studies of catalytic reactions at nanoparticles surfaces”. His studies show that radicals react extremely fast with metal and supported metal nanoparticles. The products of these reactions are long-lived metalcarbon intermediates in which their lifetime depends on the metal nature. He also has interest in “Catalytic water splitting reactions” and developed very efficient water oxidation catalysts based on co-hydrous-oxide nanoparticles supported on SiO2 nanoparticles. Recently, he developed new metal-alloys nanoparticles which show superior catalytic activity as well as TiO2 based nanocomposites which will be used for various catalytic and photocatalytic reactions.

Abstract:

Radicals reactions are of importance due to their formation near surfaces in a variety of processes, e.g. in catalytic processes, in electrochemistry, in photo-catalytic processes, in environmental processes, etc. It was therefore decided to study the mechanisms and kinetics of reaction of M°-NPs, M=Ag; Au; Cu; Pt; Pd, Pt/Au-alloy-NPs and TiO2-NPs with methyl radicals. (All the M°-NPs were prepared by reduction of the corresponding salts with NaBH4). These reactions are very fast, approaching the diffusion-controlled limit, forming long-lived transients with (M°-NP)-(CH3)n σ bonds. These transients decompose yielding C2H6 for Ag°-, Au°- and TiO2-NPs, CH4 for Cu°-NPs, for Pt°- and Pd°-NPs most methyl remain bound to the NPs, and are released as methane when H2 is added to the suspension, though some C2H6, C2H4 and oligomerization products are formed. The reaction of .C(CH3)2OH radicals with SiO2 supported metal-NPs (M°-SiO2-NCs, NCs=nanocomposites) is more complicated. At low [M°-SiO2-NCs], the NCs catalyze the reduction of water by these radicals, for M=Pt the NCs are clearly a catalyst while the Pt°-NPs are not; For M=Ag the NCs catalyze the reduction of water but considerably less than the Ag°-NPs; for M=Au both the MPs and the NCs catalyze the reduction of water. At high [M°-SiO2-NCs] the reduction of water is considerably decreased and at high doses of radicals the Pt°- and Ag°-NCs do not catalyze the reduction of water by the .C(CH3)2OH radicals and induce their disproportionation, and their reduction by H2, on the NCs surfaces. Thus, the SiO2 support affects considerably the properties of the M°-NPs and the nature of this effect depends on the nature of the M°-NPs.

Biography:

Modan Wu is currently pursuing her PhD in Department of Physics at Dublin Institude of Technology, Ireland. Currently, she is working in the area of Nanotechnology with a focus on “Double encapsulation chitosan nanoparticle preparation, chitosan nanoparticle surface modification and antibacterial abilities”.

Abstract:

Crohn’s disease (CD) is a chronic inflammatory bowel disease that presents as discontinuous transmural inflammation in any portion of gastrointestinal tract. Currently, there is no cure for CD, drug treatment typically prioritizes reducing the inflammation that triggers the symptoms, improving long-term prognosis by limiting associated complications. The predominant form of treatment is a combination of anti-inflammatory and immune system suppresser drugs, in addition to antibiotics such as prednisone (PD) and ciprofloxacin (CPX). In this study, double-layered chitosan (Cs) nanoparticles (NPs) were formulated through crosslinking with tripolyphosphate (TPP) in the presence of PD and CPX via ionotropic gelation method. The physicochemical properties (size and zeta potential) of the nanoparticles were determined by dynamic light scattering, and morphology through scanning electron microscopy. Firstly, PD was encapsulated within the Cs nanoparticle matrix, with average sizes presenting at 150-200 nm, followed by secondary coating with CPX which gave rise to final nanoparticle sizes of 350-450 nm. The maximum drug encapsulation efficiency (EE %) for PD and CPX was 20% and 70%, respectively. EE% was found to be affected by the drug loading concentration, pH value and ratio of chitosan to TPP. The optimal ratio between chitosan and TPP is 3. Release studies on the optimum formulations showed that 30% of CPX released after 3 h on incubation in simulated gastric fluid (SFG, pH 1.2) followed by 60% after 20 h in simulated intestinal fluid (SIF, pH 6.8). The antibacterial activity of PD: CPX loaded NPs and native PD and CPX were assessed against E. coli and S. aureus via zone inhibition, minimum inhibitory concentration and minimum bactericidal concentration (MBC). The results showed that PD: CPX loaded Cs NPs could inhibit the growth of various bacteria tested. Live/dead staining flow cytometry was used as an alternative to traditional MBC assay to confirm the bactericidal nature of NPs.

Biography:

Kepsutlu Burcu is a PhD student and has her expertise in “Evaluation of morphological and functional effects of biologically relevant nanoparticles on cells via X-ray tomography”. With this technique, she showed that nanoparticles induce a significant remodeling of cellular organelle composition within non-apoptotic cells. She also utilized this relatively beneficial technique to track nanoparticle distribution within individual organelles and define the endocytosis pathway of nanoparticles. She found out that nanoparticles are localized in lipid droplets which may be the reason for nanoparticle localization within liver. She also found out that multivesicular bodies may exist without a limiting membrane. All these findings provide invaluable knowledge in the drug delivery field and can be utilized for investigation of different types of drugs with cells.

Abstract:

Polyethylenimine (PEI) is commonly utilized as a non-viral gene delivery vector because it destabilizes vesicle membranes enabling release of genes to their site of action in the cytoplasm or nucleus. However, the precise mechanism of cytoplasmic release remains unclear. Possibilities include either pore formation or vesicle rupture of either endosomes or lysosomes. Identifying the escape route is critical because lysosomes have digestive enzymes which may impair the gene once inside, and furthermore release of lysosomal contents to the cytoplasm can be detrimental to the cell. To investigate cytoplasmic escape of PEI, we utilized X-ray tomography which can monitor 3D volumes of vitrified cells at 40 nm spatial resolutions without chemical fixation, staining or slicing. With this technique, we find that the mechanism of PEI-nanoparticle (PEI-np) escape to the cytoplasm is concentration dependent. At standard concentrations, PEI-np escapes by rupturing lysosomes. This release mechanism is relatively inefficient with limited nuclear entry of PEI, and with most PEI-np encapsulated within endosomes. Furthermore, we observe morphological signs of apoptosis such as extended mitochondria and chromatin condensation. However, at a ten-fold lower concentration of PEI-np, we detect no ruptured lysosomes and no PEI-np within lysosomes, and importantly we find a higher efficiency of escape to the cytoplasm and nucleus. At these concentrations, we find no mitochondrial elongation and significantly reduced chromatin condensation. In sum, simply by reducing the PEI-np concentration, it appears that PEI-np are directed to a different pathway in which lysosomes are not ruptured, endosomal escape and nuclear entry are more efficient and the adverse effects of PEI-np are reduced. Our results suggest that lower concentrations of PEI-np have multiple benefits for cellular gene delivery.

Biography:

Alexis Gonon is a 3rd year PhD student at Institute of Advanced Biosciences (IAB) of Grenoble, France. After a Bachelor degree in Biology at University Joseph Fourier, he completed his Master’s degree in Animal Genetics at Paris Diderot University. He has expertise in Mouse Experimentation at Pasteur Institute, France. He is involved in partnerships between IAB and several French and international companies of nanomedicine to test immune safety of these new innovative drugs.

Abstract:

Gold nanoparticles (AuNP) are increasingly used for therapeutic and diagnostic applications. Due to their small size (<200 nm), NP can increase the diffusion and effectiveness of drugs while facilitating modes of administration. Nevertheless, the potential risks for human health associated to NP exposure remain poorly documented especially about their effects on the immune system. Antigen presenting cells (APC), such as macrophages and dendritic cells, participate in the maintenance of body integrity, engulfing foreign pathogens and delivering signals to other components of the immune system. In this study, we investigated whether these functions could be altered by NP exposures. Using the macrophage cell line J774 and primary bone marrow derived dendritic cells, we have demonstrated that AuNP highly accumulate in APC. Notably, this accumulation did not alter phagocytosis capacity of macrophages. Then, analyzing expression of surface markers CD-86 and MHC-II, we established that NP exposure did not activate bone marrow derived DC. Moreover, further activation of these cells by known activators such as bacterial lipopolysaccharide (LPS) was not impaired by NP. However, in this case, the cytokine response was altered, showing reduced inflammatory cytokine production such as IL-6, IL-12 and IL-23. In a model of antigen presentation in vitro, this cytokine profile resulted into an altered development of specific immune responses. AuNP exposure led to an increase in T cell specific cytokines: IL-13 and IL-4 (indicating a shift of classical Th1/Th2 balance towards Th2) and IL-17 (standing for an alteration of T-cell fate towards Th17). All together, these results demonstrated that NP did not alter phagocytosis and DC activation. However, these NP changed cytokine responses after such activation, leading specific T cell fate towards Th2 and Th17 phenotypes. These modifications could impair the immune system physiology and contribute to chronic diseases or autoimmunity.

Biography:

Ewelina Grabowska has her expertise in “Heterogeneous photocatalysis, preparations of nanoparticles and nanomaterials, nanotechnology, functional materials, photocatalytic oxidation in presence of titanium dioxide, water and wastewater treatment, remediation technology and chemical technology evaluation”.

Abstract:

In recent years, photocatalytic processes have been intensively investigated for destruction of pollutants, hydrogen evolution, disinfection of water, air and surfaces, for the construction of self-cleaning materials (tiles, glass, fibers, etc.). Titanium dioxide (TiO2) is the most popular material used in heterogeneous photocatalysis due to its excellent properties, such as high stability, chemical inertness, non-toxicity and low cost. It is well known that morphology and microstructure of TiO2 significantly influence the photocatalytic activity. These characteristics as well as other physical and structural properties of photocatalysts, i.e., specific surface area or density of crystalline defects, could be controlled by preparation route. In this regard, TiO2 particles can be obtained by sol-gel, hydrothermal, sonochemical methods, chemical vapor deposition and alternatively, by ionothermal synthesis using ionic liquids (ILs). In the TiO2 particles synthesis, ILs may play a role of a solvent, soft template, reagent, and agent promoting reduction of the precursor or particles stabilizer during synthesis of inorganic materials. Ionic liquids (ILs) are widely applied to prepare metal nanoparticles and 3D semiconductor microparticles. Generally, they serve as a structuring agent or reaction medium (solvent); however, it was also demonstrated that ILs can play a role of a co-solvent, metal precursor, reducing as well as surface modifying agent. Based on the literature data and preliminary own investigation, it could be concluded that application of ionic liquids in semiconductors synthesis provide a modification of the morphology and enhanced the photocatalytic activity of obtained structures. In this regard, ionic liquids may play a role of a solvent, soft template, reagent, and agent promoting reduction of the precursor or particles stabilizer during preparation of inorganic material. In addition, presence of the IL on the TiO2 surface probably results in absorption of the photons and excitation of the electrons from HOMO to LUMO orbitals. Mechanism of the photo excitation could be therefore related with transfer of the electron from the LUMO level of IL to the TiO2 semiconductor conduction band. In this work, the effect of selected ILs structure and amount, as well as conditions of hydrothermal synthesis on the morphology and photoactivity of TiO2 is presented. The preparation of TiO2 microparticles with spherical structure was successfully achieved by solvothermal method, using tetra-tert-butyl orthotitanate (TBOT) as the precursor. Various molar ratios of all ILs to TBOT (IL:TBOT) were chosen. For comparison, reference TiO2 was prepared using the same method without IL addition. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller surface area (BET), NCHS analysis, and FTIR spectroscopy were used to characterize the surface properties of the samples. The photocatalytic activity of IL-assisted TiO2 photocatalysts was estimated by measuring the rate of phenol decomposition in aqueous solution as well as formation of hydroxyl radicals based on detection of fluorescent product of coumarin hydroxylation. Phenol was selected as a model contaminant because it is a non-volatile and common organic pollutant found in various types of industrial wastewater.

Biography:

Riny Yolandha Parapat has her expertise in “Synthesis of nano-crystal via microemulsions technique”. Her great passion is to create and develop nanomaterial especially in the field of Catalysis. She is also concerned about the environment; her research is now heading to the field of Green Synthesis and Biofuel Production. Her advance knowledge and experience in microemulsions making her able to synthesize and design the super active nano-catalysts in a greener way. She has discovered a new method to synthesize highly active supported nano-catalysts, so-called thermo-destabilization of microemulsions. She is a Lecturer in the course of Kinetic and Catalysis, Experimental Design, Process Control, and Plant Design.

Abstract:

In improving the catalytic activity of the noble metals, the surface morphology has become an area of investigation over the past decades. The shape control of metal particles during synthesis, that is to direct the crystallographic planes, coordination of surface atoms and bounding facets of the nanocrystals, is important. These parameters determine the number of atoms located at the edges or corners and accordingly control the surface chemistry which holds the key for improving their catalytic performance. The shape that possesses high-index planes (low-coordinated atoms) is preferable because generally it has high surface energies and thus exhibits high activity. To produce nanoparticles which have high-index planes, the preferred growth direction during synthesis is anisotropic growth. Our first attempt is to produce platinum (Pt) nanocrystals with a small size (2.5 nm) of an isotropic structure i.e., truncated octahedral and deposit them well on support materials. We followed the strategy to keep the small size but change the shape to anisotropic structure of Pt nanocrystals which produces more active sites by means of a weaker reducing agent. We found that the catalysts of anisotropic structure are more active than those of the isotropic ones and even show potential to be applied in a challenging reaction such as hydrogenation of levulinic acid. We continue our effort not only in improving the performance of the nano-catalyst, but also making it in a greener way by using natural reductant such as green tea and grape seed. We found that the produced Pt nano-catalysts are also anisotropic and active at a very mild condition in hydrogenation of levulinic acid which usually is conducted at high pressure and temperature.

Biography:

Ana Isabel Becerro completed her Degree in Pharmacy at University of Seville in 1992, Degree in Optics at University of Barcelona in 1993 and Doctor in Chemistry in 1997. She completed her Post-doctoral degree at Forschung Institut für Geochemie und Geophysik (Bayreuth, Germany) from 1998 to 2000, with a Marie Curie Research Training Network contract. In 2001, she came back to the Material Science Institute of Seville [Spanish Research Council (CSIC) - University of Seville (US)]. She has published more than 75 scientific papers in SCI journals and presented more than 50 contributions to scientific meetings. She has supervised 4 PhD students and a number of master degree students.

Abstract:

In the past few years, lanthanide (Ln)-doped rare earth (RE)-based nanoparticles (NPs) have emerged as an alternative to current imaging and sensing probes based on organic dyes or quantum dots due to the advantageous optical characteristics of Ln3+ ions. Among Ln, Nd3+ is particularly interesting because it is excited and emits within the first and second biological windows, in which the radiation is weakly attenuated by tissues. Thus, improving the sensitivity of the assays and lowering tissue damage. Among the Ln3+-doped RE-based NPs, fluoride-based matrices are preferred because they show a high luminescent efficiency due to their low phonon energies. Particularly, Ba1-xLnxF2+x nanoparticles have shown to be excellent up conversion bio probes as well as optimal contrast agents for X-ray computed tomography. The few reported methods for the synthesis of uniform Ba1-xLnxF2+x-based NPs required the use of high T (~300 ºC) and oleic acid as capping agent, which led to hydrophobic particles and needed therefore a second step to make them water dispersible. The purpose of this study is to find a synthetic route of Nd3+-doped Ba, Lu fluoride NPs using a one-step process in the absence of any capping agents to render hydrophilic uniform nanoparticles at much lower temperatures than the methods cited above. Findings: Uniform, 50 nm diameter, hydrophilic Nd3+-doped Ba0.3Lu0.7F2.7 NPs were synthesized using a simple precipitation method consisting in the aging of an ethylene glycol solution containing Lu acetate, Ba(NO3)3 and a fluoride-based ionic liquid. The composition and crystal structure of the un-doped NPs were analyzed with ICP and XRD, which revealed a BaF2 cubic crystal structure that is able to incorporate 70 mol% of Lu3+ ions. This finding contrasts with the reported phase diagram of the system, where the maximum solubility is around 30 mol%. Nd3+ ions up to, at least 2.5 mol%, entered the Ba0.3Lu0.7F2.7 cubic structure without altering the morphology of the un-doped NPs. The Nd-doped NPs exhibited NIR luminescence when excited at 810 nm and absorbed X-ray photons, thus demonstrating to be useful as contrast agents in both bio-imaging and X-ray computed tomography.

Biography:

Crismar Patacsil completed his MS in Physics at University of Philippines Diliman, Quezon in 2004 and is currently a PhD student at Ateneo de Manila University under Dr. Rapahel Guerrero as his dissertation adviser. Currently, he is an Assistant Professor in Department of Physical Sciences, College of Science at University of Philippines Baguio, Baguio City.

Abstract:

We present results of electrowetting experiments employing droplets formed from aqueous suspensions of gold nanoparticles. A planar electrowetting system, consisting of a platinum wire electrode and a bottom copper electrode with an insulating silicone (polydimethylsiloxane) layer, is used to observe changes in droplet contact angle when an external electric field is applied. The equilibrium contact angle at 0 V decreases with increasing nanoparticle concentration, dropping from 100.40 for pure deionized water to 94.70 for a 0.5 μM nanofluid. Increasing the nanoparticle content also lowers the required voltage for effective actuation. With actuation at 15 V, contact angle decreases by 9% and 35% for droplets formed from pure water and a 0.5 μM nanoparticle suspension, respectively. Contact angle saturation is observed with nanofluid droplets, with the threshold voltage decreasing as nanoparticle concentration rises. Maximum droplet actuation before contact angle saturation is achieved at only 10 V for a concentration of 0.5 μM. A proposed mechanism for the enhanced electrowetting response of a nanofluid droplet involves a reduction in surface tension of the droplet as nanoparticles accumulate at the liquidvapor interface.

Biography:

Laleh Alisaraie is an Assistant Professor at School of Pharmacy, Memorial University of Newfoundland, Canada.

Abstract:

Carbon nanotubes (CNTs) can play key roles in small molecule transportations. They can cross through the cell membrane while maintaining interactions with their cargos. There are a wide range of molecules that can be carried by these nanoparticles which include both small chemicals and proteins. In this talk, I will discuss our recent findings regarding some of the possible modifications of CNTs structures for their application as efficient nano-carriers for certain biomolecular cargos.

Biography:

Iva Rezić is the Head of Department of Applied Chemistry at University of Zagreb where she leads the group for synthesis and characterization of metallic nanoparticles. She has two PhDs and expertise in Material Science and Characterization, Nanotechnology, Chemical Trace Elements Analysis and Statistical Modeling of Complex Mixtures. She is an Editor-in-Chief of TEDI journal, Editor of four and Reviewer of 33 journals. She actively participates as a member of various associations, commissions and committees.

Abstract:

Statement of the Problem: Limited natural resources and the exponential growth of the population lead to dramatic changes in production, consumption, transportation and storage of food. The application of nanoparticles in packaging affects its antibacterial, mechanical, thermal and barrier properties, but also increases the safety of food and shelf life of the product. This work therefore, presents the methodology of synthesis, characterization and application of metallic nanoparticles as antimicrobial components for application on biodegradable polymers foreseen as the future packaging materials.

Methodology & Theoretical Orientation: We apply enzymes to synthesize metallic nanoparticles, reveal the kinetics and mechanism of reactions, and characterize nanoparticles by classical (SEMEDX, FTIR, ICPOES, GFAAS) and beyond-stateof- the-art (GEMMA, PDMA, MALDI-TOF-MS/MS) instrumental methods. After synthesis and characterization, the antimicrobial activity of nanoparticles was tested against model microorganisms (Staphylococcus aureus, Escherichia coli, Candida albicans) using statistical method design of experiment. Antimicrobial mixtures of nanoparticles were further applied with dip-coating on polymers by sol-gel process using 3-glycidyloxypropyltrimethoxysilane (GLYMO) precursor.

Findings: We produced metallic nanoparticles, optimized their antimicrobial activity and characterized polymers with antimicrobial layers. Enzymatic synthesis of nanoparticles at moderate temperatures ensured mild production conditions and enabled lower energy consumption. In our future work, we plan to produce a prototype of antibacterial biodegradable packaging using additive technology (3D-printing).

Conclusion & Significance: This multidisciplinary research work is significant for different scientific, industrial and technological applications: Enzymatic synthesis of nanoparticles is economically and ecologically favorable approach; usage of biodegradable polymers with metallic nanoparticles is the priority of food and packaging industry; optimization of highest antimicrobial activity of NPs mixture using design of experiment offers an innovation in formulation and; prototyping by 3D printing enables wide variety of additional applications. Therefore, we expect a significant outcome of this project and strengthening further collaboration with our industrial and academic partners.

Biography:

Francesca Frascella completed her degree in Advanced Chemical Methodologies at University of Torino in 2005 and PhD in Materials Science and Technology at Politecnico di Torino in 2009. During her PhD, she spent four months at Center for Photonics and Photonic Materials, Department of Physics of University of Bath (UK). Since 2009, she is a Post-doc Researcher at Politecnico di Torino. Her past activities concerned the preparation and surface chemical modification of porous silicon-based materials for applications in sensing. Furthermore, she was devoted to the chemical modification of several materials surface, both inorganic and polymeric, especially by means of plasma-assisted techniques. Currently, her research activity is focused on “New azo-polymer materials for reversible patterning of substrates hosting living cell cultures”. She is author of more than 25 peer-reviewed papers in international journals.

Abstract:

In recent years, micro and nano-structured polymeric films have attracted significant interest because of their promising potential application in many areas; including micro-fluidics, smart surfaces, photonics and tissue engineering. Nowadays, a plethora of processing technologies are available for fabricating complex polymeric architectures which are mostly static in nature, i.e., they cannot be morphologically modified once fabricated. Light-responsive materials such as azobenzene polymeric compounds (generally referred to as azopolymers) can overcome such a limitation opening the opportunity to active manipulate in terms of morphology, physical and mechanical properties a pre-patterned architectures, which are intrinsically static once fabricated. In azopolymeric films, a directional mass-migration effect can be triggered depending on the radiation wavelength, intensity, polarization state and topological charge, e.g. in vortex beams. Despite the underlying mechanism is still unclear to some extent, mass-migration in azopolymers has been widely exploited in the past for fabricating large-area periodic microstructures also known as Surface Relief Gratings (SRG) by exploiting intensity and/or polarization interference. In such a situation, lithographed azopolymeric patterns that could be subsequently modified by irradiation in controlled conditions are particularly attractive. For instance, irradiation with a linearly polarized light can elongate circular micro-pillars resulting in an ellipsoidal shape, wherein the elongation is along the polarization direction of the illumination beam. The light-induced contraction and expansion reshaping strategy of a polymeric structure shows exciting potential for a number of applications including microfluidics, lithography and tissue engineering. Tuning cells behavior in response to material manipulation cues
is a promising goal in biology.

Biography:

Emre Seker completed his PhD at Ankara University and Near East University respectively. He is a Lecturer and Clinical Specialist at Eskisehir Osmangazi University, Department of Prosthodontics. He has published more than 30 papers and presentations and continues to study on “Surface treatment techniques of dental materials, CADCAM implant dentistry and plasma technology”.

Abstract:

Since Co-Cr alloy is the most widely used base material for constructing dental prosthesis, many different efforts have been provided to enhance their surface energy and wettability with various surface modification procedures. Adhesion capability and surface activation of restorative materials remain as a goal for reliable clinical performance of dental restorations. Durable and strong adhesive bonding between the frameworks or between different materials in the structure of prosthesis is necessary to withstand the varied challenges in the oral environment. The acceptable bond strength depends on the wettability between the adhered surfaces and adhesive, which is necessary to ensure adhesion. Wetting is the first condition for providing adhesion. Titanium nitride (TiN) is a member of the refractory transition metal nitrides family which exhibits properties characteristic of both covalent and metallic compounds. TiN has many advantages such as including intrinsic biocompatibility, sufficient corrosion resistance, reduction of bacteria, and its suitability for use in patients who have a metal allergy to vanadium, nickel and cobalt. TiN is also a suitable material for the hard coating of various dental materials and dental surgical instruments in order to improve their surface properties. In particular, the TiN coating that provides a diffusion barrier and biocompatible surface has been applied using a metal sputtering technique in order to fabricate biocompatible prostheses. Seven Co-Cr discs were machined and smoothed with silicon polishing discs. The RF sputtering system was used for the depositions of TiN. An RF power supply of 13.56 MHz was used. Mechanical polishing was performed to reduce the surface roughness. The samples were cleaned in 96% ethanol and distilled water. The dental samples were coated with a thickness of 100 nm TiN. The surface roughness was evaluated in a control group and in groups with different plasma-jet exposure application times (30-60-120 seconds). Kinpen 09 plasma jet was used in this study. The distance between nozzle and sample surface was approximately 5 mm. Argon gas was used as carrier gas at a flow of 5l/min at 2.5 bar pressure. The average surface roughness (Ra) and contact angle (CA) measurements were recorded via an atomic force microscope (AFM) and tensiometer, respectively. According to the results with an increase in the application time, an apparent increment was observed for Ra and a remarkable reduction in CA was observed in all groups. It is concluded that the argon plasma-jet technology could enhance the roughening and wetting performance of Co-Cr dental material.

Biography:

Basak Kusakci Seker has completed her PhD at Hacettepe University and Near East University respectively. She is a Lecturer and Clinical Specialist at Eskisehir Osmangazi University, Department of Periodontology. She has published more than 20 papers and presentations and continues to study on “Dental implant surgery, dental laser applications, plasma disinfection and wound healing and bone regeneration techniques”.

Abstract:

The collagen membrane is used in guided tissue regeneration which include the regeneration of lost tissues that surround the teeth or implants by forming new bone, new cementum, and (around teeth) a new periodontal ligament. Collagen membranes should be biodegradable, biocompatible, have high porosity in the nano-size range for cell attachment and have adequate mechanical strength. The aim of this pilot study was to evaluate the effect of non-thermal atmospheric pressure plasma (NTAP) jet application on the wettability and contact angle (CA) of collagen membrane by tensiometer. Four collagen membrane specimens were prepared and cut with area of 5x5 mm. Plasma jet (kinpen 09) was used in this study. The plasma stream had a length of 11 mm. The distance between nozzle and membrane was approximately 5 mm. Argon gas was used as carrier gas at a flow of 5l/min at 2.5 bar pressure. Roughly 15 mm2 of membrane surface was treated for 30 second, 60 second and 120 second with plasma jet. Tear tests (tensiometer) give a better comparison among different materials as they provide information on the energy or force required to propagate a tear through the material. The test was initiated with a 7 mm long central cut. Tear propagation was monitored as a function of the vertical displacement at the constant rate of 1 mm/min, up to a maximum displacement of 10 mm. According to results of this study, a remarkable reduction in CA was observed in all groups and it can be assumed that NTAP application improve the wettability over previous collagen membranes which is an important benefit because of the porous structure of membrane support cell attachment and proliferation.

Biography:

Gurpreet Kaur has completed her PhD in Physics at Indian Institute of Technology, Roorkee, India in 2016. She has been working as an Assistant Professor in Department of Physics at Dr. B. R. Ambedkar National Institute of Technology, Jalandhar since 2016. Her current research area of interest is “Synthesis of nanomaterials for optical device applications”.

Abstract:

Cuprous oxide, (Cu2O) is a promising p-type semiconductor, finds applicability in a wide range of photo conversion devices. Pulsed laser deposition technique is employed to grow doped Cu2O thin films. Doping mechanism of silver (Ag), aluminium (Al) and (Ag+Al) in Cu2O thin films is illustrated in this report. The Al, Ag doped and (Al+Ag) co-doped Cu2O targets are prepared by the solid state reaction method by mixing Cu2O powder with Al2O3 and Ag2O, powders respectively, in stoichiometric ratios. The doping profile of both Al and Ag in Cu2O is kept 5%. For co-doped, it is 2.5% Al and 2.5% Ag in Cu2O. An Nd:YAG laser operating at wavelength 355 nm and energy 100 mJ/pulse is used to ablate the targets of (Cu2O:Al), (Cu2O:Ag) and (Cu2O:Al:Ag). X-ray diffraction analysis depicts the polycrystalline nature of the films, with a cubic crystal structure and having small crystallite size. UV-visible optical transmittance versus wavelength spectrum of these films describes low transmission i.e. 10-20%, due to the large absorption coefficient (α) for Cu2O material. The large values of absorption coefficient enable the photovoltaic and optical applications of the Cu2O films. The energy band gap of the films is determined using the Tauc’s plot relation, shown in figure 1. The optical band gap is increased with doping and it varies in the range of 2.65−2.84 eV. The increased band gap of doped thin films is attributed to the substitution of Al and Ag ions for the oxygen ions. Due to this substitution, width of the valence band is reduced to enlarge the band gap. Room temperature current voltage (I-V) plot indicates low resistivity (ρ~10-2 Ω-cm) of the films. The obtained results are of high relevance and indicate potential applications of the grown thin films in devices such as solar cells, photo detectors and optical sources.

Biography:

Peng-Sheng Wei completed his PhD in Mechanical Engineering department at University of California, Davis, in 1984. He has been a Professor in Department of Mechanical and Electro-Mechanical Engineering of National Sun Yat-Sen University, Kaohsiung, Taiwan, since 1989. He has contributed to advancing the understanding of and to the applications of electron and laser beam, plasma, and resistance welding through theoretical analyses coupled with verification experiments. He has published more than 80 journal papers and given keynote or invited speeches in international conferences more than 70 times. He was a Fellow of American Welding Society (AWS) in 2007 and a Fellow of American Society of Mechanical Engineers (ASME) in 2000. He has been the Xi-Wan Chair Professor at National Sun Yat-sen University (NSYSU) since 2009.

Abstract:

This study numerically investigates transport processes during the melting of an array of nanoparticles on a surface subject to an electromagnetic wave or laser beam in a transverse magnetic (TM) mode. The TM mode represents magnetic field to be perpendicular to the incident plane of electrical field. A systematical investigation of heating and melting of an array of nanoparticles on a surface is essentially required to understand 3-D printing and different types of plasma processing and nanotechnology. The results show that electromagnetic wave propagating along the boundary between two media leads to a distributed heat input and magnetic force on the surface. Fluid flow and heat transfer associated with surface deformation result in complicated transport phenomena between nanoparticles, especially for different frequencies and radii of incident electromagnetic wave.

Biography:

Norberto Arzate has been involved in theoretical studies of the linear and nonlinear optical response of surfaces and nanostructures. In particular, he has performed numerical calculations of spectra of dielectric function, second order nonlinear susceptibilities. Besides, he has applied the optical techniques of reflectance anisotropy and second harmonic generation in order to study surfaces. Recently, he has been interested in coherent control phenomena such as optical spin and current injection in surfaces and atomic monolayers .

Abstract:

Statement of the Problem: Two-dimensional materials have recently attracted great attention from the scientific community due to their interesting and quiet different properties from their bulk counterparts. For instance, the band gap value depends on the number of atomic monolayers that the material has. In addition, some materials might have spin-polarized states, which is favorable for studies of spintronics. Here, we have studied theoretically the phenomenon of optical spin injection which is generated when incident circularly-polarized light creates spin-polarized electrons into the conduction bands of the atomic system. We analyze the respective one-photon optical spin injection spectra some 2D systems. In particular, we discuss corresponding results for the atomic transition-metal dichalcogenide monolayers of molybdenum disulfide MoS2.

Methodology & Theoretical Orientation: We present calculations for spectra of the degree of spin polarization that is calculated in a full-band structure scheme. In order to obtain wave functions and eigenvalues of the quantum mechanical system, we have employed density functional theory. In order to correct the band gap energy, the quasiparticle GW approximation is applied.

Findings: It has been obtain the maximum value of 1 for the absolute value of the degree of spin polarization of the electrons for the one monolayer structure at the K valley.

Conclusion & Significance: It is possible to inject spin-polarized electrons to the conduction bands of atomic semiconducting monolayers by the incidence of circularly polarized light. This effect might be useful for the coherent control of the spin of the electron in spintronic devices.