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Title: EXTRACTION, CONCENTRATION, AND DETECTION OF FOODBORNE PATHOGENS USING GLYCAN-COATED MAGNETIC NANOPARTICLES AND A GOLD NANOPARTICLE COLORIMETRIC BIOSENSOR
Creator: Dester, Emma Faith
Date: 2022
Collection: Electronic Theses & Dissertations
Description: In this work, a rapid method for foodborne pathogen extraction and concentration using magnetic nanoparticles (MNPs) was integrated with a gold nanoparticle (GNP) colorimetric DNA biosensor for fast and accessible detection of target bacteria. Experiments for both extraction and detection were conducted first using pure cultures without interfering food matrix components and followed by testing in food matrices commonly associated foodborne outbreaks. Magnetic concentration was tested with...
Show moreIn this work, a rapid method for foodborne pathogen extraction and concentration using magnetic nanoparticles (MNPs) was integrated with a gold nanoparticle (GNP) colorimetric DNA biosensor for fast and accessible detection of target bacteria. Experiments for both extraction and detection were conducted first using pure cultures without interfering food matrix components and followed by testing in food matrices commonly associated foodborne outbreaks. Magnetic concentration was tested with three bacterial species: Listeria spp., Escherichia coli O157, and Staphylococcus aureus. Then, a colorimetric GNP biosensor was developed and tested for E. coli O157. Glycan-coated MNPs are ideal for foodborne pathogen concentration due to their low cost, simple storage conditions, and bacteria binding capabilities. Meanwhile, GNPs visibly change color upon aggregation, which allows for easy use in colorimetric biosensors without the need for expensive analytical equipment. Results from this study indicate concentration of bacteria to up to 60 times its initial concentration in buffer solution and 11 times in select food matrices. In addition, the colorimetric biosensor was capable of differentiating between target and non-target DNA from pure cultures at concentrations as low as 2.5 ng/μL. Finally, the integrated extraction and detection assay was capable of detecting E. coli O157 from contaminated flour. This assay shows immense promise for rapid foodborne pathogen detection, and evidence-based recommendations for continued optimization have also been identified.
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Title: Gas-phase synthesis of semiconductor nanocrystals and its applications
Creator: Rajib, Md, 1983-
Date: 2016
Collection: Electronic Theses & Dissertations
Description: Luminescent nanomaterials is a newly emerging field that provides challenges not only to fundamental research but also to innovative technology in several areas such as electronics, photonics, nanotechnology, display, lighting, biomedical engineering and environmental control. These nanomaterials come in various forms, shapes and comprises of semiconductors, metals, oxides, and inorganic and organic polymers. Most importantly, these luminescent nanomaterials can have different properties...
Show moreLuminescent nanomaterials is a newly emerging field that provides challenges not only to fundamental research but also to innovative technology in several areas such as electronics, photonics, nanotechnology, display, lighting, biomedical engineering and environmental control. These nanomaterials come in various forms, shapes and comprises of semiconductors, metals, oxides, and inorganic and organic polymers. Most importantly, these luminescent nanomaterials can have different properties owing to their size as compared to their bulk counterparts. Here we describe the use of plasmas in synthesis, modification, and deposition of semiconductor nanomaterials for luminescence applications.Nanocrystalline silicon is widely known as an efficient and tunable optical emitter and is attracting great interest for applications in several areas. To date, however, luminescent silicon nanocrystals (NCs) have been used exclusively in traditional rigid devices. For the field to advance towards new and versatile applications for nanocrystal-based devices, there is a need to investigate whether these NCs can be used in flexible and stretchable devices. We show how the optical and structural/morphological properties of plasma-synthesized silicon nanocrystals (Si NCs) change when they are deposited on stretchable substrates made of polydimethylsiloxane (PDMS). Synthesis of these NCs was performed in a nonthermal, low-pressure gas phase plasma reactor. To our knowledge, this is the first demonstration of direct deposition of NCs onto stretchable substrates.Additionally, in order to prevent oxidation and enhance the luminescence properties, a silicon nitride shell was grown around Si NCs. We have demonstrated surface nitridation of Si NCs in a single step process using non‒thermal plasma in several schemes including a novel dual-plasma synthesis/shell growth process. These coated NCs exhibit SiNx shells with composition depending on process parameters. While measurements including photoluminescence (PL), surface analysis, and defect identification indicate the shell is protective against oxidation compared to Si NCs without any shell growth.Gallium Nitride (GaN) is one of the most well-known semiconductor material and the industry standard for fabricating LEDs. The problem is that epitaxial growth of high-quality GaN requires costly substrates (e.g. sapphire), high temperatures, and long processing times. Synthesizing freestanding NCs of GaN, on the other hand, could enable these novel device morphologies, as the NCs could be incorporated into devices without the requirements imposed by epitaxial GaN growth. Synthesis of GaN NCs was performed using a fully gas-phase process. Different sizes of crystalline GaN nanoparticles were produced indicating versatility of this gas-phase process. Elemental analysis using X-ray photoelectron spectroscopy (XPS) indicated a possible nitrogen deficiency in the NCs; addition of secondary plasma for surface treatment indicates improving stoichiometric ratio and points towards a unique method for creating high-quality GaN NCs with ultimate alloying and doping for full-spectrum luminescence.
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Title: Physical properties and transformations of low-dimensional systems
Creator: Liu, Dan (Graduate of Michigan State University)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Evolving from the macroscopic scale to the nanometer scale, inparticular by reducing the dimensionality, fundamental properties(such as electronic and mechanical properties) of certain systemsexhibit dramatic changes, which not only give rise to a wide rangeof emergent phenomena, but also boost technology developmentincluding nanoelectronics, optoelectronics and catalysis. In thisthesis, I utilized combined techniques including densityfunctional theory (DFT), molecular dynamic simulations (MD...
Show moreEvolving from the macroscopic scale to the nanometer scale, inparticular by reducing the dimensionality, fundamental properties(such as electronic and mechanical properties) of certain systemsexhibit dramatic changes, which not only give rise to a wide rangeof emergent phenomena, but also boost technology developmentincluding nanoelectronics, optoelectronics and catalysis. In thisthesis, I utilized combined techniques including densityfunctional theory (DFT), molecular dynamic simulations (MD),continuum elasticity approach, and the tight-binding model toconduct a systematic study on low-dimensional nanostructuresregarding their electronic and mechanical properties as well asunderlying microscopic transformation mechanisms between differentstructural allotropes.First, I briefly introduce the motivation and background of thisthesis. Then, in Chapter 2, I describe the computationaltechniques, mainly the DFT approach, on which most of my thesis isbased.In Chapters 3 and 4, I apply the continuum elasticity method tostudy the phonon spectrum of two-dimensional (2D) andone-dimensional (1D) systems. My results highlight advantages ofthe continuum elasticity approach especially for the flexuralacoustic phonon modes close to the $\Gamma$ point, which areotherwise extremely hard to converge in atomistic calculationsthat use very large supercell sizes.From Chapter 5 to Chapter 7, I focus on allotropes of groupIII, V and VI elements and study boththeir stability and microscopic transformation mechanisms from oneallotrope to another. First, I predicted a stable phosphorus coilstructure, which may form by reconstruction of red phosphorous,and which was synthesized by filling a carbon nanotube withsublimed red phosphorus. Second, I proposed two stable 2Dallotropes of Se and Te. I also suggested and evaluated apromising fabrication approach starting from natural 1D structuresof these elements. After considering low-dimensional chargeneutral systems, I changed my focus to study the effect of netcharge on the equilibrium structure. Considering a heterostructureof alternating electron donor layers an monolayers of boron, Ihave identified previously unknown stable 2D boron allotropes thatmay change their structure under different levels of chargetransfer.From Chapter 8 to Chapter 10, I focus mainly on carbon-basednanomaterials and their properties. In Chapter 8, I proposed a wayto enhance the density of states at the Fermi level in dopedC60 crystals in order to increase their superconductingcritical temperature to room temperature. In Chapter 9, I haveinvestigated a shear instability twisted bilayer graphene usingthe tight binding model. This system is susceptible to very smallstructural changes, since it becomes superconducting in a verynarrow range of twist angles near the 'magic angle'. In Chapter10, I introduced the cause of an unusual negative Poisson ratioand a shape-memory behavior in porous graphene with anartificially designed pattern.In Chapter 11, I finally present general conclusions of my PhDThesis.
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Title: Nanorobotic end-effectors : design, fabrication, and in situ characterization
Creator: Fan, Zheng (Of Michigan State University)
Date: 2015
Collection: Electronic Theses & Dissertations
Description: Nano-robotic end-effectors have promising applications for nano-fabrication, nano-manufacturing, nano-optics, nano-medical, and nano-sensing; however, low performances of the conventional end-effectors have prevented the widespread utilization of them in various fields. There are two major difficulties in developing the end-effectors: their nano-fabrication and their advanced characterization in the nanoscale. Here we introduce six types of end-effectors: the nanotube fountain pen (NFP), the...
Show moreNano-robotic end-effectors have promising applications for nano-fabrication, nano-manufacturing, nano-optics, nano-medical, and nano-sensing; however, low performances of the conventional end-effectors have prevented the widespread utilization of them in various fields. There are two major difficulties in developing the end-effectors: their nano-fabrication and their advanced characterization in the nanoscale. Here we introduce six types of end-effectors: the nanotube fountain pen (NFP), the super-fine nanoprobe, the metal-filled carbon nanotube (m@CNT)-based sphere-on-pillar (SOP) nanoantennas, the tunneling nanosensor, and the nanowire-based memristor. The investigations on the NFP are focused on nano-fluidics and nano-fabrications. The NFP could direct write metallic "inks" and fabricating complex metal nanostructures from 0D to 3D with a position servo control, which is critically important to future large-scale, high-throughput nanodevice production. With the help of NFP, we could fabricate the end-effectors such as super-fine nanoprobe and m@CNT-based SOP nanoantennas. Those end-effectors are able to detect local flaws or characterize the electrical/mechanical properties of the nanostructure. Moreover, using electron-energy-loss-spectroscopy (EELS) technique during the operation of the SOP optical antenna opens a new basis for the application of nano-robotic end-effectors. The technique allows advanced characterization of the physical changes, such as carrier diffusion, that are directly responsible for the device's properties. As the device was coupled with characterization techniques of scanning-trasmission-electron-microscopy (STEM), the development of tunneling nanosensor advances this field of science into quantum world. Furthermore, the combined STEM-EELS technique plays an important role in our understanding of the memristive switching performance in the nanowire-based memristor. The developments of those nano-robotic end-effectors expend the study abilities in investigating the in situ nanotechnology, providing efficient ways in in situ nanostructure fabrication and the advanced characterization of the nanomaterials.
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Title: Sensing and manipulation in a nano-bio environment using atomic force microscopy based robotic system
Creator: Li, Guangyong
Date: 2006
Collection: Electronic Theses & Dissertations

Title: Equilibrium geometry and electronic properties of nanostructures
Creator: Kwon, Young-Kyun
Date: 1999
Collection: Electronic Theses & Dissertations

Title: Electronic and structural properties of functional nanostructures
Creator: Yang, Teng
Date: 2009
Collection: Electronic Theses & Dissertations

Title: Modeling and control for micro and nano manipulation
Creator: Wejinya, Uchechukwu C.
Date: 2007
Collection: Electronic Theses & Dissertations

Title: Characterization of the thermodynamics and deformation behavior of styrene-butadiene-styrene grafted with polyhedral oligomeric silsesquioxanes
Creator: Drazkowski, Daniel B.
Date: 2007
Collection: Electronic Theses & Dissertations

Title: A compact fully on-chip impedance spectroscopy system
Creator: Rairigh, Daniel J.
Date: 2007
Collection: Electronic Theses & Dissertations

Title: Polyelectrolyte multilayer coatings for conductive nanomaterials patterning and anti-wrinkling applications
Creator: Hendricks, Troy Richard
Date: 2008
Collection: Electronic Theses & Dissertations

Title: Fabrication of nanostructures and nanostructure based interfaces for biosensor application
Creator: Srivastava, Devesh
Date: 2008
Collection: Electronic Theses & Dissertations

Title: Fundamental electronic and structural properties of carbon onions in extreme environments
Creator: Al-Duhileb, Raied A.
Date: 2010
Collection: Electronic Theses & Dissertations

Title: Thermoset polymer-layered silicic acid nanocomposites
Creator: Wang, Zhen
Date: 1997
Collection: Electronic Theses & Dissertations

Title: Structural transitions in nanoscale systems
Creator: Yoon, Mina
Date: 2004
Collection: Electronic Theses & Dissertations

Title: Effects of nanoscale inclusions on the dynamics and properties of polymer melts
Creator: Tuteja, Anish
Date: 2006
Collection: Electronic Theses & Dissertations

Title: Multiscale modeling and computation of nano-electronic transistors and transmembrane proton channels
Creator: Chen, Duan
Date: 2010
Collection: Electronic Theses & Dissertations
Description: The miniaturization of nano-scale electronic transistors, such as metal oxide semiconductor field effect transistors (MOSFETs), has given rise to a pressing demand in the new theoretical understanding and practical tactic for dealing with quantum mechanical effects in integrated circuits. In biology, proton dynamics and transport across membrane proteins are of paramount importance to the normal function of living cells. Similar physical characteristics are behind the two subjects, and model...
Show moreThe miniaturization of nano-scale electronic transistors, such as metal oxide semiconductor field effect transistors (MOSFETs), has given rise to a pressing demand in the new theoretical understanding and practical tactic for dealing with quantum mechanical effects in integrated circuits. In biology, proton dynamics and transport across membrane proteins are of paramount importance to the normal function of living cells. Similar physical characteristics are behind the two subjects, and model simulations share common mathematical interests/challenges. In this thesis work, multiscale and multiphysical models are proposed to study the mechanisms of nanotransistors and proton transport in transmembrane at the atomic level.For nano-electronic transistors, we introduce a unified two-scale energy functional to describe the electrons and the continuum electrostatic potential. This framework enables us to put microscopic and macroscopic descriptions on an equal footing at nano-scale. Additionally, this model includes layered structures and random doping effect of nano-transistors.For transmembrane proton channels, we describe proton dynamics quantum mechanically via a density functional approach while implicitly treat numerous solvent molecules as a dielectric continuum. The densities of all other ions in the solvent are assumed to obey the Boltzmann distribution. The impact of protein molecular structure and its charge polarization on the proton transport is considered in atomic details. We formulate a total free energy functional to include kinetic and potential energies of protons, as well as electrostatic energy of all other ions on an equal footing.For both nano-transistors and proton channels systems, the variational principle is employed to derive nonlinear governing equations. The Poisson-Kohn-Sham equations are derived for nano-transistors while the generalized Poisson-Boltzmann equation and Kohn-Sham equation are obtained for proton channels. Related numerical challenges in simulations are addressed: the matched interface and boundary (MIB) method, the Dirichlet-to-Neumann mapping (DNM) technique, and the Krylov subspace and preconditioner theory are introduced to improve the computational efficiency of the Poisson-type equation. The quantum transport theory is employed to solve the Kohn-Sham equation. The Gummel iteration and relaxation technique are utilized for overall self-consistent iterations.Finally, applications are considered and model validations are verified by realistic nano-transistors and transmembrane proteins. Two distinct device congurations, a double-gate MOSFET and a four-gate MOSFET, are considered in our three dimensionalnumerical simulations. For these devices, the current uctuation and voltage threshold lowering effect induced by discrete dopants are explored. For proton transport, a realistic channel protein, the Gramicidin A (GA) is used to demonstrate the performance of the proposed proton channel model and validate the efficiency of the proposed mathematical algorithms. The electrostatic characteristics of the GA channel is analyzed with a wide range of model parameters. Proton channel conductances are studied over a number of applied voltages and reference concentrations. Comparisons with experimental data are utilized to verify our model predictions.
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Title: Sensing and actuation of bead-tagged biomaterials on standard CMOS substrates
Creator: Abu-Nimeh, Faisal T.
Date: 2011
Collection: Electronic Theses & Dissertations
Description: Magnetic molecular-level sensing and manipulation are emerging as lab-on-chip platforms. These platforms entail low-cost, low-power, high efficiency, and portable implementations. Biomaterials are usually attached to magnetic beads and used in bio-analysis applications such as sorting, counting, purification, and assembly. Some of the potential applications are 2D biological or artificial tissue assembly at the micro-scale level.Here, we present the design and demonstration of a self...
Show moreMagnetic molecular-level sensing and manipulation are emerging as lab-on-chip platforms. These platforms entail low-cost, low-power, high efficiency, and portable implementations. Biomaterials are usually attached to magnetic beads and used in bio-analysis applications such as sorting, counting, purification, and assembly. Some of the potential applications are 2D biological or artificial tissue assembly at the micro-scale level.Here, we present the design and demonstration of a self-contained device for sensing and manipulating biomaterials tagged with magnetic beads. The core elements of the device consist of all-integrated programmable magnetic coil arrays for pseudo-parallel sensing and actuation, which are capable of maneuvering small (bead-bound) bio-objects individually and larger ones collaboratively. Our design does not require any external magnetic sources. It relies on the magnetic field generated by planar on-chip coil arrays. The coil arrays are selectively and dynamically controlled. Each element, composed of the coil and its logical control circuitry, can detect bio-objects in the order of 1$\mu$m diameter, or manipulate them using eight-level programmable AC or DC magnetic fields. All array sensing and actuation components are shared and multiplexed to reduce the overall imprint. The components are isolated and tuned to work at 900MHz by incorporating high-speed switching (up to 40MHz) for seamless pseudo-parallel execution.In addition, we present a new and unique on-chip biomedical proof-of-concept application. Adopting trends in neuroscience, we employ the magnetic beads to initiate and elongate neuronal axons in vitro on-chip. This application domain will assist in better understanding and studying the process of neuroregeneration, propel future clinical applications, and provide the foundation of techniques needed to wire ``neuronal circuits'' using living cells.
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Title: Simulation study of lipid bilayer/nanoparticle interactions
Creator: Musolff, Corey Evan
Date: 2013
Collection: Electronic Theses & Dissertations
Description: A coarse-grained model is used to simulate lipid bilayers (LB) interacting with nanoparticles (NP). Different equilibrium states are observed as the size of the NP is varied along with the interaction strength between the NP and LB. Sufficient attraction causes the NP to become wrapped by the LB. Large NP are able to form pores in the LB. These various outcomes are explained using a continuum theory.The same model is used to simulate pore healing in LB. It is observed that the area of the...
Show moreA coarse-grained model is used to simulate lipid bilayers (LB) interacting with nanoparticles (NP). Different equilibrium states are observed as the size of the NP is varied along with the interaction strength between the NP and LB. Sufficient attraction causes the NP to become wrapped by the LB. Large NP are able to form pores in the LB. These various outcomes are explained using a continuum theory.The same model is used to simulate pore healing in LB. It is observed that the area of the pore decreases linearly with time as explained by Allen-Cahn theory. Bulk properties of the LB can be used to predict the closing time of a pore as well as the amount of charge able to flow through the pore while it is open.
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Title: Balanced improvement of high performance concrete material properties with modified graphite nanomaterials
Creator: Peyvandi, Amirpasha
Date: 2014
Collection: Electronic Theses & Dissertations
Description: Graphite nanomaterials offer distinct features for effective reinforcement of cementitious matrices in the pre-crack and post-crack ranges of behavior. Thoroughly dispersed and well-bonded nanomaterials provide for effective control of the size and propagation of defects (microcracks) in matrix, and also act as closely spaced barriers against diffusion of moisture and aggressive solutions into concrete. Modified graphite nanomaterials can play multi-faceted roles towards enhancing the...
Show moreGraphite nanomaterials offer distinct features for effective reinforcement of cementitious matrices in the pre-crack and post-crack ranges of behavior. Thoroughly dispersed and well-bonded nanomaterials provide for effective control of the size and propagation of defects (microcracks) in matrix, and also act as closely spaced barriers against diffusion of moisture and aggressive solutions into concrete. Modified graphite nanomaterials can play multi-faceted roles towards enhancing the mechanical, physical and functional attributes of concrete materials. Graphite nanoplatelets (GP) and carbon nanofibers (CNF) were chosen for use in cementitious materials. Experimental results highlighted the balanced gains in diverse engineering properties of high-performance concrete realized by introduction of graphite nanomaterials. Nuclear Magnetic Resonance (NMR) spectroscopy was used in order to gain further insight into the effects of nanomaterials on the hydration process and structure of cement hydrates. NMR exploits the magnetic properties of certain atomic nuclei, and the sensitivity of these properties to local environments to generate data which enables determination of the internal structure, reaction state, and chemical environment of molecules and bulk materials. 27Al and 29Si NMR spectroscopy techniques were employed in order to evaluate the effects of graphite nanoplatelets on the structure of cement hydrates, and their resistance to alkali-silica reaction (ASR), chloride ion diffusion, and sulfate attack. Results of 29Si NMR spectroscopy indicated that the percent condensation of C-S-H in cementitious paste was lowered in the presence of nanoplatelets at the same age. The extent of chloride diffusion was assessed indirectly by detecting Friedel's salt as a reaction product of chloride ions with aluminum-bearing cement hydrates. Graphite nanoplatelets were found to significantly reduce the concentration of Friedel's salt at different depths after various periods of exposure to chloride solutions, pointing at the benefits of nanoplatelets towards enhancement of concrete resistance to chloride ion diffusion. It was also found that the intensity of Thaumasite, a key species marking sulfate attack on cement hydrates, was lowered with the addition of graphite nanoplatelets in concrete exposed to sulfate solutions. Experimental evaluations were conducted on scaled-up production of concrete nanocomposite in precast concrete plants. Full-scale reinforced concrete pipes and beams were produced using concrete nanocomposites. Durability and structural tests indicated that the use of graphite nanoplatelets, alone or in combination with synthetic (PVA) fibers, produced significant gains in the durability characteristics, and also benefited the structural performance of precast reinforced concrete products. The material and scaled-up structural investigations conducted in the project concluded that lower-cost graphite nanomaterials (e.g., graphite nanoplatelets) offer significant potentials as multi-functional additives capable of enhancing the barrier, durability and mechanical performance of concrete materials. The benefits of graphite nanomaterials tend to be more pronounced in higher-performance concrete materials.
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