Physical Sciences and Mathematics Commons^™

Synthesis Of Gold Nanoparticles Via Pulsed Liquid Ablation For Use In The Photodynamic Therapy Of Bacteria, Justice Ben Yosef

Masters Theses & Specialist Projects

With the ever-increasing threat of antibiotic resistant bacteria, alternative treatment methods have been developed including photodynamic therapy (PDT). Within the PDT process, photosensitizers are used to generate reactive oxygen species (ROS) and facilitate the cell termination process. This work lays the conceptual foundation for the functionalization of the photosensitizer methylene blue (MB) with gold nanoparticles (AuNPs) and INF-55 as a potential inhibitor of the AcrAB-TolC efflux pump to enhance the effectivity of the PDT process.

AuNPs were synthesized using pulsed laser ablation in an aqueous citrate solution. Both nanosecond and picosecond pulse durations, as well as both 532 nm and …

Quantification Of Spent Coffee Ground Extracts By Roast And Brew Method, And Their Utility In A Green Synthesis Of Gold And Silver Nanoparticles, Brian G Yust, Niny Z Rao, Evan T Schwarzmann, Madisyn H Peoples

College of Life Sciences Faculty Papers

Nanotechnology has become increasingly important in modern society, and nanoparticles are routinely used in many areas of technology, industry, and commercial products. Many species of nanoparticle (NP) are typically synthesized using toxic or hazardous chemicals, making these methods less environmentally friendly. Consequently, there has been growing interest in green synthesis methods, which avoid unnecessary exposure to toxic chemicals and reduce harmful waste. Synthesis methods which utilize food waste products are particularly attractive because they add value and a secondary use for material which would otherwise be disposed of. Here, we show that spent coffee grounds (SCGs) that have already been …

Characterization Of Extracellular Vesicles Derived From Mesenchymal Stromal Cells By Surface-Enhanced Raman Spectroscopy., Nina M Ćulum, Tyler T Cooper, Gillian I Bell, David A Hess, François Lagugné-Labarthet

Chemistry Publications

Extracellular vesicles (EVs) are secreted by all cells into bodily fluids and play an important role in intercellular communication through the transfer of proteins and RNA. There is evidence that EVs specifically released from mesenchymal stromal cells (MSCs) are potent cell-free regenerative agents. However, for MSC EVs to be used in therapeutic practices, there must be a standardized and reproducible method for their characterization. The detection and characterization of EVs are a challenge due to their nanoscale size as well as their molecular heterogeneity. To address this challenge, we have fabricated gold nanohole arrays of varying sizes and shapes by …

Characterization Of Extracellular Vesicles Derived From Mesenchymal Stromal Cells By Surface-Enhanced Raman Spectroscopy., Nina M Ćulum, Tyler T Cooper, Gillian I Bell, David A Hess, François Lagugné-Labarthet

Chemistry Publications

Extracellular vesicles (EVs) are secreted by all cells into bodily fluids and play an important role in intercellular communication through the transfer of proteins and RNA. There is evidence that EVs specifically released from mesenchymal stromal cells (MSCs) are potent cell-free regenerative agents. However, for MSC EVs to be used in therapeutic practices, there must be a standardized and reproducible method for their characterization. The detection and characterization of EVs are a challenge due to their nanoscale size as well as their molecular heterogeneity. To address this challenge, we have fabricated gold nanohole arrays of varying sizes and shapes by …

Characterization Of Extracellular Vesicles Derived From Mesenchymal Stromal Cells By Surface-Enhanced Raman Spectroscopy., Nina M. Culum, Tyler T. Cooper, Gillian I. Bell, David A. Hess, François Lagugné-Labarthet

Chemistry Publications

Extracellular vesicles (EVs) are secreted by all cells into bodily fluids and play an important role in intercellular communication through the transfer of proteins and RNA. There is evidence that EVs specifically released from mesenchymal stromal cells (MSCs) are potent cell-free regenerative agents. However, for MSC EVs to be used in therapeutic practices, there must be a standardized and reproducible method for their characterization. The detection and characterization of EVs are a challenge due to their nanoscale size as well as their molecular heterogeneity. To address this challenge, we have fabricated gold nanohole arrays of varying sizes and shapes by …

Nanoscale Building Blocks: Bridging The Gap Between Potential And Realized Applications, Nicole Ritter

Theses and Dissertations (Comprehensive)

The vast potential of nanoparticles and nanotechnology remains largely untapped; the crucial bottleneck being the knowledge gap between making and using nanoparticles (NPs). This PhD work bridges this gap by focusing on synthesizing nanoparticles with applications at the forefront. Four peer-reviewed publications are presented in Chapters 3-6, a safety and toxicological perspective is given in Chapter 7, and current work and future progress are summarized in Appendix 1. Bimorphic silver nanoparticles were prepared, presenting an innovative method to synthesize diverse nanostructures using polymeric surface blocking to break symmetry in seeded regrowth (Chapter 3).¹ Silver stars with D_5h symmetry …

Environmentally Friendly Synthesis Of Transition Metalorganic Hybrid Nanocomposites, Aubrey N. Penn

Masters Theses & Specialist Projects

Research on metal nanoparticles (MNPs) synthesis and their applications for optoelectronic devices has been a recent interest in the fields of nanoscience and nanotechnology Photovoltaics are one of such systems in which MNPs have shown to be quite useful, due to unique physical, optical, magnetic, and electronic properties, including the metal nanoparticles synthesized in this research.

Owing to the challenges with the most common physical and chemical methods of preparing MNPs, including the use of high temperatures, toxic reducing agents, and environmentally hazardous organic solvents, there is a critical need for a benign synthesis procedure for MNPs. In this work, …

Cost Effective Surface Functionalization Of Gold Nanoparticles With A Mixed Dna And Peg Monolayer For Nanotechnology Applications, Risheng Wang, Isabella Bowling, Wenyan Liu

Chemistry Faculty Research & Creative Works

A cost effective and generally applicable co-functionalization of gold nanoparticles with a mixed DNA and PEG polymers is reported. Compared to the pure DNA functionalization method, this protocol uses a much smaller amount of thiol-DNA to achieve a similar binding efficacy of gold nanoparticles with DNA origami nanostructures. The lower consumption of DNA provides a scaling-up potential for the application of DNA-nanoparticle conjugates in nanotechnology.

Metal-Organic Hybrid Nanocomposites For Energy Harvesting Applications, Thulitha Madawa Abeywickrama

Masters Theses & Specialist Projects

Various synthetic methods have been developed to produce metal nanostructures including copper and iron nanostructures. Modification of nanoparticle surface to enhance their characteristic properties through surface functionalization with organic ligands ranging from small molecules to polymeric materials including organic semiconducting polymers is a key interest in nanoscience. However, most of the synthetic methods developed in the past depend widely on non-aqueous solvents, toxic reducing agents, and high temperature and high-pressure conditions. Therefore, to produce metal nanostructures and their nanocomposites with a simpler and greener method is indeed necessary and desirable for their nano-scale applications. Hence the objective of this thesis …

Au Nanostructured Surfaces For Electrochemical And Localized Surface Plasmon Resonance-Based Monitoring Of Α-Synuclein-Small Molecule Interactions., Xin R Cheng, Gregory Q Wallace, François Lagugné-Labarthet, Kagan Kerman

Chemistry Publications

In this proof-of-concept study, the fabrication of novel Au nanostructured indium tin oxide (Au-ITO) surfaces is described for the development of a dual-detection platform with electrochemical and localized surface plasmon resonance (LSPR)-based biosensing capabilities. Nanosphere lithography (NSL) was applied to fabricate Au-ITO surfaces. Oligomers of α-synuclein (αS) were covalently immobilized to determine the electrochemical and LSPR characteristics of the protein. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were performed using the redox probe [Fe(CN)6](3-/4-) to detect the binding of Cu(II) ions and (-)-epigallocatechin-3-gallate (EGCG) to αS on the Au-ITO surface. Electrochemical and LSPR data were complemented by Thioflavin-T (ThT) …

Au Nanostructured Surfaces For Electrochemical And Localized Surface Plasmon Resonance-Based Monitoring Of Α-Synuclein-Small Molecule Interactions., Xin R Cheng, Gregory Q Wallace, François Lagugné-Labarthet, Kagan Kerman

Chemistry Publications

In this proof-of-concept study, the fabrication of novel Au nanostructured indium tin oxide (Au-ITO) surfaces is described for the development of a dual-detection platform with electrochemical and localized surface plasmon resonance (LSPR)-based biosensing capabilities. Nanosphere lithography (NSL) was applied to fabricate Au-ITO surfaces. Oligomers of α-synuclein (αS) were covalently immobilized to determine the electrochemical and LSPR characteristics of the protein. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were performed using the redox probe [Fe(CN)6](3-/4-) to detect the binding of Cu(II) ions and (-)-epigallocatechin-3-gallate (EGCG) to αS on the Au-ITO surface. Electrochemical and LSPR data were complemented by Thioflavin-T (ThT) …

Energy Transfer From Fluorescent Proteins To Metal Nanoparticles, Suraj Saraswat, Anil Desireddy, Desheng Zheng, Lijun Guo, H. Peter Lu, Terry P. Bigioni, Dragan Isailovic

Chemistry Faculty Publications

Energy transfer plays a significant role in numerous chemical, physical, and biological processes. While the use of fluorescent proteins in Forster resonance energy transfer (FRET) studies of biomolecules is common, energy transfer between fluorescent proteins and inorganic nanoparticles has not been explored in detail. In this study, energy transfer from fluorescent phycobiliproteins to noble metal nanoparticles was analyzed. Solutions of B-phycoerythrin (B-PE) were mixed with colloidal Au and Ag nanoparticles and were characterized by steady-state and time-resolved fluorescence spectroscopy to determine the magnitude and mechanism of the energy transfer. It was found that the protein fluorescence was quenched after the …