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Development of targeted formulations for the delivery of a cytochrome c-based drug for application in cancer therapy
(2021-05-13)
The progression of a cell toward apoptosis, upon cellular stress, is accompanied by a set of characteristic events which includes permeabilization of the mitochondrial outer membrane and release of cytochrome c into the ...
Cross-linked cytochrome c-based nanoparticles for targeted and controlled cancer therapy
(2022-05-06)
Cancer is a major public health problem worldwide and is the second leading cause of death in the United States. The persistent need to develop cancer therapeutics with improved safety and efficacy provides constant fuel ...
Pickering liquid crystal emulsions: Influence of mixed-monolayer protected gold nanoparticles on colloidal stability and surfactant-induced ordering transitions
(2021-04-13)
Liquid crystal (LC) droplets dispersed in aqueous phases (e.g., LC-in-water emulsions) provide a versatile platform for the design of droplet-based LC sensors that can respond to the presence of chemical and biological ...
Synthesis and evaluation of alginate coated magnetite nanoparticles for the removal of dyes from wastewater
(2020-12-11)
The discharge of wastewater from the dyeing industry is an environmental concern across the
world. These effluents are considered highly toxic since they contain high concentrations of synthetic
dyes, which are a great ...
Bisphosphonate-based coordination complexes and immobilization thereof in titanium dioxide nanoparticles
(2022-05-02)
Coordination complexes (CCs), as well as inorganic nanoparticles, present several advantages towards nanotechnology-based cancer therapy applications. Both types of materials provide stability, specificity, low cytotoxicity, ...
Mortar mix design with fly ash and nano-silica for structural patchment
(2020-07-24)
Mortars with sufficient bonding and mechanical strength are alternative remedies to restore the original resistance of a failed structural element, prolonging its longevity. The present thesis proposed the analysis of ...
Titanium oxide nanoparticles in the freshwater ecosystem: Atya lanipes shrimp as a nanotoxicological model
(2023-05-16)
This dissertation specializes in studying and determining the environmental concentrations of an emerging pollutant of which we do not fully know, titanium oxide nanoparticles (TiO<sub>2</sub> NPs). Although we are aware of the extensive use and commercial production of this nanoparticle in the US and that there are various sources of contamination and their entry into rivers, we are almost completely unaware of the environmental concentrations that exist in Puerto Rico. There is little knowledge of the toxicological effects that could be associated with ecologically susceptible species. To date, there are no federal or state regulations for acceptable environmental concentrations in our rivers. This study aims to determine the actual status of urban and rural rivers in Puerto Rico related to the presence/absence of TiO<sub>2</sub> NPs and the specific fate and behavior in a laboratory-controlled environment. Also, we want to understand and measure how the presence of these nanoparticles in the freshwater ecosystem results in lethal and sublethal effects due to the toxicity of the TiO<sub>2</sub> NPs, on the life cycle of an endemic shrimp in Puerto Rico, Atya lanipes. The objectives of this dissertation are: 1) Determine the environmental concentrations of titanium oxide nanoparticles and the fate and behavior laboratory assessment, 2) Describe the early larval development description of the freshwater shrimp Atya lanipes Holthuis, 1963 (Decapoda: Caridea: Atyidae), 3) Establish titanium oxide nanoparticles as emerging aquatic pollutants evaluating the nanotoxicity in the freshwater shrimp larvae Atya lanipes, and 4) Determine the neurotoxicity and oxidative stress development in adult Atya lanipes shrimp exposed to titanium oxide nanoparticles. Through field and laboratory studies, we obtained for the first time the concentrations of titanium oxide nanoparticles in sediment and dissolved titanium in water from the Rio Piedras and Sabana rivers. Also, we were able to elucidate the first nine (9) larval stages of the Atya lanipes shrimp. Then, after acute and chronic exposures, we evaluated lethal and sublethal toxic effects in both larval and adult stages of the Atya lanipes shrimp. This study is an innovative one that contributes significantly to our scientific knowledge of the magnitude of the concentration of TiO<sub>2</sub> NP that we are facing. It provides a starting point to begin public policy and better management in the use and discharge of this type of nanomaterial....