Nanotechnology Commons^™

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 …

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 …

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 …

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. …