Nanotechnology Commons^™

Multigenerational Genomic And Epigenetic Effects Of Manufactured Silver Nanomaterials In Caenorhabditis Elegans, Anye Wamucho

Theses and Dissertations--Toxicology and Cancer Biology

There has been an increase in the incorporation of silver nanomaterials into consumer products due to their antimicrobial properties. Therefore there is potential for silver nanoparticles (Ag-NPs) to leach out into the environment during different life-cycle stages of these nanomaterial-containing products. Concern about the toxicity of Ag-NPs has led to investigations into their toxic effects on a variety of organisms mainly using acute and sub-chronic, single-generation exposures. The focus of this project was to understand the effects of long-term continuous multigenerational exposure to AgNO₃ and Ag-NPs in both pristine and environmentally transformed forms, on the model organism, Caenorhabditis elegans …

Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller

Electronic Theses and Dissertations

The inherent heterogeneity of tumor tissue presents a major challenge to nanoparticle-medicated drug delivery. This heterogeneity spans from the molecular to the cellular (cell types) and to the tissue (vasculature, extra-cellular matrix) scales. Here we employ computational modeling to evaluate therapeutic response as a function of vascular-induced tumor tissue heterogeneity. Using data with three-layered gold nanoparticles loaded with cisplatin, nanotherapy is simulated with different levels of tissue heterogeneity, and the treatment response is measured in terms of tumor regression. The results show that tumor vascular density non-trivially influences the nanoparticle uptake and washout, and the associated tissue response. The drug …

Challenges In Characterizing The Environmental Fate And Effects Of Carbon Nanotubes And Inorganic Nanomaterials In Aquatic Systems, Peter Laux, Christian Riebeling, Andy M. Booth, Joseph D. Brain, Josephine Brunner, Cristina Cerrillo, Otto Creutzenberg, Irina Estrela-Lopis, Thomas Gebel, Gunnar Johanson, Harald Jungnickel, Heiko Kock, Jutta Tentschert, Ahmed Tlili, Andreas Schäffer, Adriënne J. A. M. Sips, Robert A. Yokel, Andreas Luch

Pharmaceutical Sciences Faculty Publications

The current lack of commonly used protocols for dispersion, characterization, and aquatic toxicity testing of nanomaterials (NMs) has resulted in inconsistent results, which make meaningful comparisons difficult. The need for standardized sample preparation procedures that allow the reproducible generation of relevant test conditions remains a key challenge for studies of the environmental fate and aquatic toxicity of NMs. Together with the further development of optimized and cost-effective analytical techniques for physicochemical characterization that depend on reproducible sample preparation, such methods have the potential to overcome the current uncertainties with regard to NM dispersion properties, effective dose, and particle dissolution. In …

Effects Of Carboxylated Nanodiamonds On Macrophages During And After Differentiation, Maisoun E. Bani Hani

Biological Sciences Theses & Dissertations

Nanodiamonds (ND) are a carbon-based nanomaterial that are increasingly being proposed for developing novel imaging techniques, as carriers of biomolecules and therapeutic drugs, as coatings for implants, and for other biomedical applications. The exceptional chemical, mechanical, and optical properties of ND make this material suitable in a wide range of fields. The application of ND in the biomedical field is attractive but requires more in-depth investigation into the safety of ND and its interactions with different cells and systems. The effects of ND on the immune system are not fully understood or investigated and there are several controverting reports regarding …

Biokinetics Of Nanomaterials: The Role Of Biopersistence, Peter Laux, Christian Riebeling, Andy M. Booth, Joseph D. Brain, Josephine Brunner, Cristina Cerrillo, Otto Creutzenberg, Irina Estrela-Lopis, Thomas Gebel, Gunnar Johanson, Harald Jungnickel, Heiko Kock, Jutta Tentschert, Ahmed Tlili, Andreas Schäffer, Adriënne J. A. M. Sips, Robert A. Yokel, Andreas Luch

Pharmaceutical Sciences Faculty Publications

Nanotechnology risk management strategies and environmental regulations continue to rely on hazard and exposure assessment protocols developed for bulk materials, including larger size particles, while commercial application of nanomaterials (NMs) increases. In order to support and corroborate risk assessment of NMs for workers, consumers, and the environment it is crucial to establish the impact of biopersistence of NMs at realistic doses. In the future, such data will allow a more refined categorization of NMs. Despite many experiments on NM characterization and numerous in vitro and in vivo studies, several questions remain unanswered including the influence of biopersistence on the toxicity …

Use Of A Modified Greenscreen Tool To Conduct A Screening-Level Comparative Hazard Assessment Of Conventional Silver And Two Forms Of Nanosilver., Jennifer Sass, Lauren Heine, Nina Hwang

Environmental and Occupational Health Faculty Publications

BACKGROUND: Increased concern for potential health and environmental impacts of chemicals, including nanomaterials, in consumer products is driving demand for greater transparency regarding potential risks. Chemical hazard assessment is a powerful tool to inform product design, development and procurement and has been integrated into alternative assessment frameworks. The extent to which assessment methods originally designed for conventionally-sized materials can be used for nanomaterials, which have size-dependent physical and chemical properties, have not been well established. We contracted with a certified GreenScreen profiler to conduct three GreenScreen hazard assessments, for conventional silver and two forms of nanosilver. The contractor summarized publicly …

Size Dependent Translocation And Fetal Accumulation Of Gold Nanoparticles From Maternal Blood In The Rat., Manuela Semmler-Behnke, Jens Lipka, Alexander Wenk, Martin Schäffler, Furong Tian, Günter Schmid, Günter Oberdörster, Wolfgang G. Kreyling

Articles

Background

There is evidence that nanoparticles (NP) cross epithelial and endothelial body barriers. We hypothesized that gold (Au) NP, once in the blood circulation of pregnant rats, will cross the placental barrier during pregnancy size-dependently and accumulate in the fetal organism by 1. transcellular transport across the hemochorial placenta, 2. transcellular transport across amniotic membranes 3. transport through ~20 nm wide transtrophoblastic channels in a size dependent manner. The three AuNP sizes used to test this hypothesis are either well below, or of similar size or well above the diameters of the transtrophoblastic channels.

Methods

We intravenously injected monodisperse, negatively …

Toxicological Effects Of Cerium Oxide Nanoparticle Aggregates On Caenorhabditis Elegans, Steven N. Rogers

Theses, Dissertations and Capstones

Assessing the toxicity and unique reactivity of nanoparticles in biological systems has become an relevant and quickly growing area of environmental toxicology research. The broad use of nanoparticles in industrial and commercial commodities results in exposure of these nano-compounds to the environment, the ecosystems, and humans. While previous data has suggested that cerium oxide (CeO₂) nanoparticles are relatively safe to cultured cells much less is known about the potential toxicity of these materials at the organismal level. In this study we employed transgenic Caenorhabditis elegans (C. elegans) strains to assess the toxicity of CeO₂ nanoparticles under “real-world” …

Using Photoactive Vitamin Nanoparticles As Photodynamic Antimicrobial Chemotherapeutic (Pact) Agents To Treat Chronic Wounds, Rahul A. Khanke

All Capstone Projects

The objective of the proposed study is to develop new materials and methods to manage microbial growth in chronic wounds using phototherapy. Chronic wounds are considered as a worldwide health problem. The most common chronic wounds can be classified into three categories: venous ulcers, diabetic ulcers, and pressure ulcers. Venous ulcers, which usually occur in the legs, account for about 70% to 90% of chronic wounds and can become infected easily. Venous ulcers are sores that develop after veins in the legs have been damaged. These ulcers can penetrate deeply into the skin. Occasionally, if a venous ulcer persists for …

Three Models Of Anthrax Toxin Effects On The Map-Kinase Pathway And Macrophage Survival, Daniel J. Schneider

Theses and Dissertations

Lethal factor (LF), a component of anthrax toxin, is the primary virulence factor that allows Bacillus anthracis to evade the immune response by blocking the activation of mitogen-activated protein kinase (MAPK) enzymes. This research modifies three published MAPK models to reflect this signal inhibition and to estimate a first-order reaction rate by fitting the models to published viability data for two macrophage cell lines cultured with the LF-producing Bacillus anthracis-Vollum1B strain. One model appears to be ill-suited for this purpose because not all relevant MAPK components could be integrated into the inhibition equations. Despite different underlying parameters and values, the …