Nanotechnology Commons^™

Engineering Hyaluronic Acid For Biomedical Applications, Deep S. Bhattacharya

Theses & Dissertations

This work presents research using the naturally available non- sulfated carbohydrate glycosaminoglycan hyaluronic acid (HA) for the synthesis of different chemical derivatives of HA for evaluation of binding kinetics with CD44 and P- selectin proteins for applications in fluorescence image-guided surgery. Chemical derivatives of HA such as deacetylated HA (deHA), sulfated HA (sHA), and deacetylated and sulfated HA (s-deHA) were synthesized by modulating sulfating and deacetylating reagents to alter binding specificities to CD44. Modified HA derivatives and CD44 biophysical interactions were assessed by fluorescence polarization. In silico techniques were also used to determine binding using molecular docking and MM-PBSA approaches. …

Theranostics For Antiretroviral Biodistribution And Pharmacokinetics, Brendan M. Ottemann

Theses & Dissertations

RATIONALE: Our laboratories birthed the field of human immunodeficiency virus (HIV) theranostics. The new field allows simultaneous detection (diagnostics) and treatment (therapeutic) for the identification, treatment and inevitable elimination of virus in cell and tissue compartments. By employing theranostics, antiretroviral drugs (ARVs) can be tracked in lymph nodes, gut, spleen and liver. Cellular viral reservoirs including CD4+ T cell populations and mononuclear phagocytes (MP; monocytes, macrophages, microglia and dendritic cells) along with subcellular endosomal structures can now be targeted for drug delivery bringing therapeutics to areas where virus replicates. The overarching idea rests in improving precision targeted ARV delivery. …

Performance Study Of The Membrane Based Layered Double Hydroxides ‘Znal-Gh’ In The Purification Of Groundwater, Jaouad Zerhouni, Omar Qabaqous, Fouzia Rhazi Filali, Mohammed Naciri Bennani, Najib Tijani

Karbala International Journal of Modern Science

The objective of this work is focused on the preparation and characterization of plan microfiltration membrane Zn₃Al-Gh and the study of their efficiency in the treatment of ground water. This membrane was carried by using the support of the clay such as Ghassoul ‘Gh’ prepared by using dry uniaxial compaction method. The layered double hydroxides (LDH) based on Zn₃Al-CO₃with molar ratio (Zn²⁺/Al³⁺=3) was deposited on support by direct co-precipitation method.

The characterizations of the membrane LDH-Gh ‘Zn₃Al-Gh’ and deposited layer Zn₃Al-CO_3, was done by scanning …

Electrospun Fibers And Nanoparticles For The Prevention Of Sexually Transmitted Infections., Kevin Michael Tyo

Electronic Theses and Dissertations

Human immunodeficiency virus-1 (HIV-1) and herpes simplex virus 2 (HSV-2) affect hundreds of millions of people worldwide, with women disproportionately impacted by these infections. Currently, only oral pre-exposure prophylaxis (PrEP) is approved specifically for the prevention of HIV-1, but is challenged with adverse side effects associated with long-term use. Topical delivery platforms, such as gels and films, deliver agents directly to the female reproductive tract, but are limited in providing transient-release. The technology of polymeric electrospun fibers may serve as alternative topical delivery platform to the female reproductive tract. In these studies, we fabricated electrospun fibers comprised of different polymers …

Identification And Molecular Analysis Of Dna In Exosomes, Jena Tavormina

Dissertations and Theses (Open Access)

Exosomes are heterogeneous nanoparticles 50-150nm in diameter. Exosomes contain many functional cargo components, such as protein, DNA, and RNA. While protein and RNA exosome content has been extensively studied, very little work has been done to characterize exosomal DNA. Here, we demonstrate that exosomal DNA is heterogeneous and its packaging into exosomes is dependent on the cell of origin. Furthermore, through a rigorous assessment of various isolation methods, we identify Size Exclusion Chromatography (SEC) as the best method for the isolation of exosomal DNA for downstream applications. Additionally, we evaluate the methylation status of exosomal DNA and demonstrate that exosomal …

Gemcitabine Combination Nano Therapies For Pancreatic Cancer, Kamalika Samanta, Saini Setua, Sonam Kumari, Meena Jaggi, Murali Yallapu, Subhash C. Chauhan

School of Medicine Publications

Pancreatic cancer is one of the deadliest causes of cancer-related death in the United States, with a 5-year overall survival rate of 6 to 8%. These statistics suggest that immediate medical attention is needed. Gemcitabine (GEM) is the gold standard first-line single chemotherapy agent for pancreatic cancer but, after a few months, cells develop chemoresistance. Multiple clinical and experimental investigations have demonstrated that a combination or co-administration of other drugs as chemotherapies with GEM lead to superior therapeutic benefits. However, such combination therapies often induce severe systemic toxicities. Thus, developing strategies to deliver a combination of chemotherapeutic agents more securely …

Synthesizing Galactose Modified Polymeric Nanoparticles For Biofilm Inhibition Of Pseudomonas Aeruginosa, Tyler R. Flockton

Theses and Dissertations

Treating patients with antibiotics is becoming harder with the increase in antibiotic resistance. This is due to the widespread antibiotic use in clinical and agricultural settings. With antibiotic resistance outpacing new drugs making it to the market, developing new options to treat bacterial infections is and will be important. We created sugar modified nanoparticles to inhibit the biofilm formation of Pseudomonas aeruginosa.

P. aeruginosa is a gram-negative opportunistic pathogen that infects its host that has a compromised immune system. This makes it one of the most significant bacterial infection in hospitals. P. aeruginosa uses biofilms as an attack mechanism …

Developing A Dissociative Nanocontainer For Peptide Drug Delivery, Michael Patrick Kelly

Dissertations, Theses, and Capstone Projects

The potency and specificity of bioactive peptides have propelled these agents to the forefront of pharmacological research. However, delivery of peptides to their molecular target in cells is a major obstacle to their widespread application. A Trojan Horse strategy of packaging a bioactive peptide within a modified protein cage to protect it during transport, and releasing it at the target site, is a promising delivery method. Recent work has demonstrated that the viral capsid of the P22 bacteriophage can be loaded with an arbitrary, genetically-encoded peptide, and externally decorated with a cell-penetrating peptide, such as HIV-Tat, to translocate across in …

Characteristics Of Nanoparticles Emitted From Kanthal A1 And Nichrome Heaters Used In Electronic Cigarettes, Kaushal Arvind Prasad

The Journal of Purdue Undergraduate Research

No abstract provided.

Synthesis And Characterization Of Long-Acting Rilpivirine Prodrugs, James R. Hilaire

Theses & Dissertations

Antiretroviral therapy (ART) requires lifelong daily dosing to suppress viral replication, restore or maintain immune function and improve quality of life. As an alternative, long-acting (LA) antiretrovirals (ARVs) aim to deliver therapeutic drug concentrations over an extended period, ultimately requiring monthly or even more extended dosing intervals. Specifically, the success of recent clinical trials examining LA cabotegravir and rilpivirine (CAB and RPV LA) highlight the advent of these novel HIV-1 therapeutics. Further optimization of LA dosage forms are required and rests upon improving dosing frequency, injection volumes and tissue distribution to viral compartments. To this end, we report the synthesis …

Nanoporous Gold And Other Related Materials, Keith Stine

Chemistry & Biochemistry Faculty Works

No abstract provided.

Synthesis Of New Aliphatic Pseudo-Branched Polyester Co-Polymers For Biomedical Applications, Zachary Shaw

Electronic Theses & Dissertations

In this study, a hyperbranched polyester co-polymer was designed using a proprietary monomer and diethylene glycol or triethylene glycol as monomers. The synthesis was carried out using standard melt polymerization technique and catalyzed by p-Tolulenesulfonic acid. The progress of the reaction was monitored with respect to time and negative pressure, with samples being subjected to standard characterization protocols. The resulting polymers were purified using the solvent precipitation method and characterized using various chromatographic and spectroscopic methods including GPC, MALDI-TOF, and NMR. We have observed polymers with a molecular weight of 29,643 kDa and 33,996 kDa, which is ideal to be …

Behavioral Responses To Gold Nanoparticle Exposure And H2o2-Induced Oxidative Stress In Caenorhabditis Elegans, Rachel Pride, Ashley Wagner

DePaul Discoveries

Gold nanoparticles (AuNPs) have been utilized in many biomedical disciplines, most notably cancer therapy and drug delivery. Recent research suggests that with specific peptide manipulation, AuNPs can deliver drugs across the blood-brain barrier (BBB), allowing for treatment of neurodegeneration and other neurological afflictions. Neurodegeneration has been shown to be caused by oxidative stress. The present experiment aimed to assess the effects of AuNPs on C. elegans behavior that had undergone H₂O₂-induced oxidative stress. It was predicted that worms exposed to both H₂O₂ and AuNPs would have higher survival, mechanosensation, and thrashing rates than …

A Robust Delivery System For Rna Therapeutics, Suleyman Bozal

University Scholar Projects

The field of RNA therapeutics is currently undergoing both transformation and expansion. Specifically, research in lipid nanoparticle (LNP) based RNA therapeutics is gaining significant traction. Other research into mechanisms of gene regulation and manipulation, including siRNA and the CRISPR/Cas9 system have demonstrated the potential of RNA-based disease treatment. This work identifies a delivery system which can regulate expression of green fluorescent protein (GFP) in human embryonic kidney cells (HEK293) stably expressing GFP.

Analysis of siRNA-induced gene knockdown demonstrates that the current siRNA-LNP formulation is equally as effective as a commercially available transfection reagent, Lipofectamine RNAiMAX (RNAiMAX), which is designed specifically …

A Robust Delivery System For Rna Therapeutics, Suleyman Bozal

Honors Scholar Theses

The field of RNA therapeutics is currently undergoing both transformation and expansion. Specifically, research in lipid nanoparticle (LNP) based RNA therapeutics is gaining significant traction. Other research into mechanisms of gene regulation and manipulation, including siRNA and the CRISPR/Cas9 system have demonstrated the potential of RNA-based disease treatment. This work identifies a delivery system which can regulate expression of green fluorescent protein (GFP) in human embryonic kidney cells (HEK293) stably expressing GFP.

Analysis of siRNA-induced gene knockdown demonstrates that the current siRNA-LNP formulation is equally as effective as a commercially available transfection reagent, Lipofectamine RNAiMAX (RNAiMAX), which is designed specifically …

Polymeric Chloroquine: Modifying An Old Drug To Make It A Little Sweeter, Richard Sleightholm

Theses & Dissertations

Hydroxyethyl starch (HES) is a clinically used polysaccharide colloidal plasma volume expander. The goal of this study was to synthesize HES modified with hydroxychloroquine (HCQ) as a novel polymeric drug with the ability to inhibit the invasive character of pancreatic cancer (PC) cells. HES was conjugated with HCQ using a simple carbonyldiimidazole coupling to prepare Chloroquine-modified HES (CQ-HES). CQ-HES with various degrees of HCQ substitution were synthesized and characterized. In vitro studies showed CQ-HES to have a similar toxicity profile as HCQ. Confocal microscopy revealed the propensity of CQ-HES to localize to lysosomes, and mechanistic studies confirmed the ability of …

Long-Acting Nanoformulated Small Molecule Inhibitor Prodrugs For Antiviral Treatment And Prevention, Nathan Smith

Theses & Dissertations

Over 30 years of antiretroviral therapy (ART) has transformed human immunodeficiency virus type one (HIV-1) outcomes from certain death to a nearly complete and normal life. Though disease growth has slowed, the virus still creates substantial co-morbid diseases as well as social and economic burdens worldwide. Lack of success with curative efforts combined with shortcomings in global treatment remain to be properly addressed. The requirement for daily use of combination antiretroviral drugs (ARVs) in low to middle income countries - where the majority of the HIV-1 positive population resides - can lead to breaks in regimen adherence due to a …

Synthesis And Characterization Of A Long-Acting Emtricitabine Prodrug Nanoformulation, Ibrahim M. Ibrahim

Theses & Dissertations

The introduction of highly active antiretroviral therapy led to a paradigm shift in the management of HIV/AIDS changing a disease considered “a death sentence” to “a manageable chronic disease”. Nevertheless, challenges exist for successful treatment of HIV, including patient adherence to the complex daily regimens and the inability of current formulations to target viral sanctuaries. Introduction of nanoformulated antiretroviral therapy (ART) is a promising alternative to tackle these challenges. Our laboratory has been focusing on developing long-acting (LA) nanoformulated antiretrovirals and has succeeded in developing LA integrase inhibitors. However, challenges for this approach extend to a range of short-acting hydrophilic …

Development Of A Long-Acting Nanoformulation Of Dolutegravir For Prevention And Treatment Of Hiv-1 Infection, Brady Sillman

Theses & Dissertations

Dolutegravir (DTG) is a potent human immunodeficiency virus type 1 (HIV-1) integrase strand-transfer inhibitor (INSTI) with a high barrier to viral drug resistance. However, opportunities to improve its profile abound. These include extending the drug’s apparent half-life, increasing penetrance to “putative” viral reservoirs, and reducing inherent toxicities. These highlight, in part, the need for long-acting, slow effective release antiretroviral therapy (LASER ART) delivery schemes. A long-acting (LA) DTG was made by synthesizing a hydrophobic and lipophilic prodrug encased with poloxamer (P407) surfactant. This modified DTG (MDTG) reduced systemic metabolism and polarity, increased lipophilicity and membrane permeability, improved encapsulation, and formed …

Using Green Emitting Ph-Responsive Nanogels To Report Environmental Changes Within Hydrogels: A Nanoprobe For Versatile Sensing, Mingning Zhu, Dongdong Lu, Shanglin Wu, Qing Lian, Wenkai Wang, L. Andrew Lyon, Weiguang Wang, Paulo Bártolo, Brian R. Saunders

Engineering Faculty Articles and Research

Remotely reporting the local environment within hydrogels using inexpensive laboratory techniques has excellent potential to improve our understanding of the nanometer-scale changes that cause macroscopic swelling or deswelling. Whilst photoluminescence (PL) spectroscopy is a popular method for such studies this approach commonly requires bespoke and time-consuming synthesis to attach fluorophores which may leave toxic residues. A promising and more versatile alternative is to use a pre-formed nanogel probe that contains a donor/acceptor pair and then “dope” that into the gel during gel assembly. Here, we introduce green-emitting methacrylic acid-based nanogel probe particles and use them to report the local environment …

Development Of Bar-Peptide Nanoparticles And Electrospun Fibers For The Prevention And Treatment Of Oral Biofilms., Mohamed Yehia Mahmoud

Electronic Theses and Dissertations

Background: Periodontal diseases are globally prevalent inflammatory disorders that affect ~47% of U.S adults. Porphyromonas gingivalis (Pg) has been identified as a “keystone” pathogen that disrupts host-microbe homeostasis and contributes to the initiation and progression of periodontitis. Pg associates with oral streptococci in supragingival plaque and this interaction represents a potential target for therapeutic intervention. Previously our group developed a peptide (designated BAR), that potently inhibits Pg/Streptococcus gordonii (Sg) adherence in vitro and Pg virulence in a murine model of periodontitis. While efficacious, BAR (SspB Adherence Region) provided transient inhibition and required higher concentrations of BAR to disrupt established …

Facile Fabrication Of Superhydrophobic And Superolephilic Materials For Effective Oil Absorbtion And Oil-Water Separation, Ali Tawfeeq Abdulhussein

Theses and Dissertations

Surfaces that have a water contact angle (WCA) above 150° and a negligible difference between the receding and advancing contact angles are superhydrophobic, meaning that a simple, minimal tilt will cause water droplets to roll off the surfaces. Superhydrophobic surfaces are found in nature and can possess several fascinating properties, including the ability to self-clean. A typical superhydrophobic surface has micro/nanostructure roughness and low surface energy, which combine to give it its unusual anti-wetting properties. Because of their unique capabilities, superhydrophobic surfaces have interested scientists in research and industry fields for years. In recent decades, researchers have developed a number …

All-Optical Control Of Lead Halide Perovskite Microlasers, Nan Zhang, Yubin Fan, Kaiyang Wang, Zhiyuan Gu, Yuhan Wang, Li Ge, Shumin Xiao, Qinghai Song

Publications and Research

Lead halide perovskites based microlasers have recently shown their potential in nanophotonics. However, up to now, all of the perovskite microlasers are static and cannot be dynamically tuned in use. Herein, we demonstrate a robust mechanism to realize the alloptical control of perovskite microlasers. In lead halide perovskite microrods, deterministic mode switching takes place as the external excitation is increased: the onset of a new lasing mode switches off the initial one via a negative power slope, while the main laser characteristics are well kept. This mode switching is reversible with the excitation and has been explained via cross-gain saturation. …

Å-Indentation For Non-Destructive Elastic Moduli Measurements Of Supported Ultra-Hard Ultra-Thin Films And Nanostructures, Filippo Cellini, Yang Gao, Elisa Riedo

Publications and Research

During conventional nanoindentation measurements, the indentation depths are usually larger than 1–10 nm, which hinders the ability to study ultra-thin films (<10 >nm) and supported atomically thin two-dimensional (2D) materials. Here, we discuss the development of modulated Å-indentation to achieve sub-Å indentations depths during force-indentation measurements while also imaging materials with nanoscale resolution. Modulated nanoindentation (MoNI) was originally invented to measure the radial elasticity of multi-walled nanotubes. w, by using extremely small amplitude oscillations (<<1 Å) at high frequency, and stiff cantilevers, we show how modulated nano/Å-indentation (MoNI/ÅI) enables non-destructive measurements of the contact stiffness and indentation modulus of ultra-thin ultra-stiff films, including CVD diamond films (~1000 GPa stiffness), as well as the transverse modulus of 2D materials. Our analysis demonstrates that in presence of a standard laboratory noise floor, the signal to noise ratio of MoNI/ÅI implemented with a commercial atomic force microscope (AFM) is such that a dynamic range of 80 dB –– achievable with commercial Lock-in amplifiers –– is sufficient to observe superior indentation curves, having indentation depths as small as 0.3 Å, resolution in indentation <0.05 Å, and in normal load <0.5 nN. Being implemented on a standard AFM, this method has the potential for a broad applicability.

Fabrication Of Polyelectrolyte Nanoparticles Through Hydrophobic Interaction, Ruginn Porce Catarata

Electronic Theses and Dissertations

Anticancer drugs like gemcitabine (GEM) are used to treat cancers such as, pancreatic ductal adenocarcinoma (PDAC). However, the use of free gemcitabine yields challenges including cytotoxicity to healthy cells and poor circulation time. By encapsulating GEM in nanoparticles these challenges can be overcome. In this study poly(acrylic acid) (PAA)-GEM nanoparticles are fabricated by coupling GEM onto PAA. The particle formation is driven by the hydrophobic interaction of GEM, which collects in the core of the nanoparticle, forming a PAA shell. The nanoparticles were optimized by studying the PAA/GEM ratio and pH during fabrication. Characteristics of the nanoparticles including size, morphology …

Development Of 3d Printed And 3d Metal-Based Micro/Nanofabricated, And Nano-Functionalized, Microelectrode Array (Mea) Biosensors For Flexible, Conformable, And In Vitro Applications, Charles Didier

Electronic Theses and Dissertations

Emerging fields such as "Organs on a Chip", disease modeling in vitro, stem cell manufacturing and wearable bioelectronics are demanding rapid development of 3D Microelectrode Arrays (MEAs) for electrical interfacing with biological constructs. The work reported in this thesis focuses on two developmental tracks: "Dynamic 3D MEAs" and metal microfabrication for 3D MEAs. In the first part of the thesis, we explore the capabilities and limitations of 3D printed microserpentines (µserpentines) and utilize these structures to develop dynamic 3D microelectrodes. Analytical modeling of µserpentines flexibility followed by integration into a flexible Kapton® package and PDMS insulation are demonstrated. These 3D …

Nutritional Transporter Mediated Drug Delivery For Cancer, Siddharth S. Kesharwani

Electronic Theses and Dissertations

Recent advancements in nanotechnology have unfolded novel opportunities in medicine, especially in targeted therapeutics and imaging for cancer. However, the majority of the existing nanotechnologies for cancer suffer from shortcomings such as (i) rapid elimination from the systemic circulation before reaching the cancer tissue. (ii) poor tumor accumulation, targeting, and penetration due to inadequate vasculature and extensive extracellular matrix in the tumor. Thus, overcoming these two limitations of nanotechnology is of considerable interests for cancer researchers. In this dissertation, we demonstrate the feasibility of glucose-modified nanoparticles (GLU-NPs) as an efficient cancer targeted-delivery system for enhancing the systemic circulation time and …

Preparation And Characterization Of Multimodal Hybrid Organic And Inorganic Nanocrystals Of Camptothecin And Gold, Christin P. Hollis, Alan K. Dozier, Barbara L. Knutson, Tonglei Li

Pharmaceutical Sciences Faculty Publications

We demonstrate a novel inorganic-organic crystalline nanoconstruct, where gold atoms were imbedded in the crystal lattices as defects of camptothecin nanocrystals, suggesting its potential use as simultaneous agents for cancer therapy and bioimaging. The incorporation of gold, a potential computed tomography (CT) contrast agent, in the nanocrystals of camptothecin was detected by transmission electron microscope (TEM) and further quantified by energy dispersive X-ray spectrometry (EDS) and inductively coupled plasma-optical emission spectrometers (ICP-OES). Due to gold's high attenuation coefficient, only a relatively small amount needs to be present in order to create a good noise-to-contrast ratio in CT imaging. The imbedded …

Therapeutic Delivery Technology And Its Economic Impact, Paul E. Savas Jr.

Senior Honors Theses

Therapeutic delivery technology is a current area of high interest in both university and industrial settings. These technologies are being developed in order to deliver therapeutic agents, such as genes, proteins, and drugs, to patients more efficiently. Nanoscale delivery vehicles have proven to be useful for these applications; these vehicles may either be naturally produced or chemically synthesized. The physical properties of these nanomaterials must be characterized correctly using instrumentation that evaluates their size, morphology, and potential for agglomeration. These technologies represent a high-growth economic area that fosters entrepreneurship and innovation. Because of this innovative spirit, research and economic interest …

Mechanisms And Thermodynamics Of The Influence Of Solution-State Interactions Between Hpmc And Surfactants On Mixed Adsorption Onto Model Nanoparticles, Salin Gupta Patel

Theses and Dissertations--Pharmacy

Nanoparticulate drug delivery systems (NDDS) such as nanocrystals, nanosuspensions, solid-lipid nanoparticles often formulated for the bioavailability enhancement of poorly soluble drug candidates are stabilized by a mixture of excipients including surfactants and polymers. Most literature studies have focused on the interaction of excipients with the NDDS surfaces while ignoring the interaction of excipients in solution and the extent to which the solution-state interactions influence the affinity and capacity of adsorption. Mechanisms by which excipients stabilize NDDS and how this information can be utilized by formulators a priori to make a rational selection of excipients is not known.

The goals of …