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A Novel Device And Nanoparticle-Based Approach For Improving Diagnosis And Treatment Of Pelvic Inflammatory Disease, Natasha Faith Cover

USF Tampa Graduate Theses and Dissertations

Pelvic Inflammatory Disease (PID) is one of the most common causes of morbidity in women. PID is a polymicrobial infection of the female reproductive tract, and is associated with pelvic pain, abnormal uterine bleeding, and tubal damage that can lead to ectopic pregnancies and infertility. It is curable but the effects of PID can be permanent if not properly diagnosed and treated. PID presents as a spectrum of disease and is often missed at early stages; even acute PID can be difficult to diagnose, as there is no single conclusive diagnostic test. Currently, PID is identified and treated syndromically because …

In Vitro Evaluation Of Electrospun Chitosan Mats Crosslinked With Genipin As Guided Tissue Regeneration Barrier Membranes, Peter A. Norowski Jr.

Electronic Theses and Dissertations

Guided tissue regeneration (GTR) is a surgical technique commonly used to exclude bacteria and soft tissues from bone graft sites in oral/maxillofacial bone graft sites by using a barrier membrane to maintain the graft contour and space. Current clinical barrier membrane materials based on expanded polytetrafluoroethylene (ePTFE) and bovine type 1 collagen are non-ideal and experience a number of disadvantages including membrane exposure, bacterial colonization/biofilm formation and premature degradation, all of which result in increased surgical intervention and poor bone regeneration. These materials do not actively participate in tissue regeneration, however bioactive materials, such as chitosan, may provide advantages such …

Design And Evaluation Of A Novel Composite Chitosan-Poly(Lactide-Co-Glycolide) Microsphere Based System For Bone Tissue Engineering Applications, Marvin Magan Mecwan

Electronic Theses and Dissertations

Nearly 60% to 67% of all injuries that occur annually within the US are due to musculoskeletal injuries, with over a million people requiring implants and bone grafting materials to reconstruct bone defects. Our lab has previously developed composite chitosan/nano-hydroxyapatite microsphere based bone grafts that had good compressive strengths, supported bone cell growth and mineralization in vitro, demonstrated biocompatibility and osteoconductivity in a rat calvarial defect model, and when loaded with rhBMP-2 was osteoinductive in a rat muscle pouch model. However, degradation of these scaffolds was very slow which may have limited the amount of new bone formed in vivo. …

Preparations And Characters For Acetamiprid Of Molecular Imprinted Polymer Electrochemical Sensors, Bin Liu, Yong-Xing Huang, Hui-Ting Lian, Hong-Mei Wu

Journal of Electrochemistry

A novel molecularly imprinted membranes electrochemical sensor with good memory capacity to acetamiprid was developed. Based on electrodeposition technique, chitosan was deposited onto the surface of gold electrode as a functional polymer matrix along with aimed molecules acetamiprid and glutaraldehyde as a crosslinking agent. Cationic probe Ru(NH3)6Cl3 was employed to indirectly investigate the electrochemical characteristics as well as the imprinted effect of the sensors. The results showed that the sensors had a specific recognition to acetamiprid compared to the structural similarity midacloprid and other pesticide. There is more sensitive response to acetamiprid at imprinted sensors than that at nonprinted sensors …

Self-Repairable Polymeric Networks: Synthesis And Network Design, Biswajit Ghosh

Dissertations

This dissertation describes the design, synthesis and development of a new class of polymeric networks that exhibit self-repairing properties under UV exposure. It consists of two parts: (a) modification and synthesis of oxetane (OXE), and oxolane (OXO) substituted chitosan (CHI) macromonomer, and (b) design, and synthesis of self-repairing polyurethane (PUR) networks consisting of modified chitosan. Unmodified CHI consisting of acetamide (-NHCOCH₃), primary hydroxyl (-OH), and amine (-NH₂) functional groups were reacted with OXE or OXO compounds under basic conditions in order to substitute the 1° –OH groups, and at the same time, convert -NHCOCH₃ functionalities …

Effectiveness Of Different Molecular Weights And Concentrations Of Chitosan On Enteric Viral Surrogates, Robert Hamilton Davis

Masters Theses

Chitosan is known to be antibacterial and antifungal, but information on its effectiveness against foodborne viruses is limited. Enteric viruses are a major concern in food safety, especially human noroviruses which are the leading cause of nonbacterial gastroenteritis. The overall goal of this research was to determine the antiviral effectiveness of chitosan. The specific objectives were to determine the effects of molecular weight (MW) and concentration of chitosan against the cultivable enteric viral surrogates, feline calicivirus (FCV-F9), murine norovirus (MNV-1), and bacteriophages (MS2 and phiX174). Purified chitosans (53, 222, 307, 421, ~1,150kDa) were dissolved in water, 1% acetic acid, or …

Depolymerization Of Chitosan By High-Pressure Homogenization And The Effect On Antimicrobial Properties, Deidra Shannon Lyons

Masters Theses

The focus of this study was to look at relationship between polydispersity caused by high pressure homogenization and molecular weight dependent antimicrobial activity of chitosan. It has been shown that chitosan has antimicrobial activity against bacteria, fungi, and viruses. Chitosan is obtained by partial de-N-acetylation of chitin which, consists of a ß 1-4 copolymer of glucosamine and N-acetylglucosamine residues. In this experiment we compared chitosan of sixteen different molecular weights after being processed through a high pressure homogenizer. Processed chitosan (420 kDa average molecular weight, 30% of acetylation) was dissolved in a 1% (v/v) acetic acid in water to a …

Design And Preliminary Investigation Of Crosslinked Chitosan Sponges For Tailorable Drug Delivery And Infection Control, Ashley Cox Parker

Electronic Theses and Dissertations

Musculoskeletal wound infections can be difficult to treat, often resulting in multiple surgeries and increased costs, and can be complicated by antibiotic resistant bacteria. The aim of this study was to use genipin, alone or with poly(n-isopropylacrylamide) (PNIPAM), to crosslink chitosan sponges for a tailorable, degradable local drug delivery system to treat known musculoskeletal pathogens. Lyophilized uncrosslinked, genipin crosslinked, and PNIPAM/ genipin crosslinked chitosan sponges were evaluated in vitro for degradation, antibiotic uptake, elution, biologic activity, and biocompatibility. Crosslinked chitosan sponges exhibited decreased degradation and increased antibiotic uptake and elution. PNIPAM/genipin crosslinked sponges had the highest and prolonged release of …

Development Of An Inverse Liquid Chromatographic Technique To Measure Adsorption Of Amino Acid Sorbates Onto Chitosan, Yamama Hafeez

Biological and Agricultural Engineering Undergraduate Honors Theses

Drug delivery is described as the localized sustained delivery of a pharmaceutical agent to the systemic blood circulation and hence to the site of action to produce a desired pharmacological effect [1]. There are three principle ways of drug delivery, first being the injection of the drug loaded on microspheres in this method of drug delivery, microspheres are formed using a combination of ink-jet technology and single emulsion-solvent evaporation techniques. Microspheres of a certain size are produced such as to administer the desired route of administration and the rate of the drug release [1]. Another form of drug delivery commonly …

Pembuatan Sediaan Tablet Mengapung Famotidin Menggunakan Kompleks Polielektrolit Kitosan-Pektin Sebagai Bahan Matriks, Erny Sagita, Effionora Anwar, Silvia Surini

Majalah Ilmu Kefarmasian

Floating tablet is one of the drug delivery system retained in the stomach which aims to prolong the lag time of the drug in the stomach. This principle can be used to improve the efficacy of famotidine in treating diseases in the stomach The purpose of this research is to develop dosage form afloat by using Chitosan Pectin Electrolytes (PEC) as matrix then used as the matrix in tablet dosage form with famotidine as a drug model. PEC also combined with hydroxypropylmethylcellulose (HPMC) with different. PEC was also combined with hydroxypropilmethylcellulose (HPMC) in different concentrations. The results of the dissolution …

Biofuel Cell Anode For Nad-Dependent Enzymes, Ovalles Rosalba Rincón

Chemical and Biological Engineering ETDs

Enzymatic biofuel cells are a very attractive young technology based on utilization of natural, renewable and plentiful resources that offer an alternative energy source. Most fuel cells run on hydrogen; but it is extremely expensive and difficult to obtain, which is why research has moved to target fuels that are already available in nature, avoiding high costs of production, both economically and environmentally. Several biofuels with very high energy densities are available to us in abundance, but the challenges to make use of them are plenty. These biofuels contain several carbon-to-carbon bonds which make their oxidation processes significantly more complex …

Efficacy Of Organically Certifiable Materials And Natural Compounds Against Foliar Hemibiotrophic And Necrotrophic Fungi In Cantaloupe And Tomato, Merari Feliciano-Rivera

University of Kentucky Doctoral Dissertations

Kentucky reported a solid 13.1% growth in certified organic land from 1997 to 2002. The relative lack of research on disease management practices in Kentucky consistent with organic regulations is an issue that needs to be addressed to provide more reliable information to local farmers. Thus, the first objective of this research was to investigate the potential disease control obtained with natural, organically certifiable spray materials against Colletotrichum orbiculare in vitro and in vivo. The second objective was to test certifiable spray materials in combinations to identify synergistic interactions. The third objective was to evaluate Organic Material Review Institute …

Reinforced Chitosan-Based Heart Valve Scaffold And Utility Of Bone Marrow-Derived Mesenchymal Stem Cells For Cardiovascular Tissue Engineering, Mohammad Z. Albanna

Wayne State University Dissertations

Recent research has demonstrated a strong correlation between the differentiation profile of mesenchymal stem cells (MSCs) and scaffold stiffness. Chitosan is being widely studied for tissue engineering applications due to its biocompatibility and biodegradability. However, its use in load-bearing applications is limited due to moderate to low mechanical properties. In this study, we investigated the effectiveness of a fiber reinforcement method for enhancing the mechanical properties of chitosan scaffolds. Chitosan fibers were fabricated using a solution extrusion and neutralization method and incorporated into porous chitosan scaffolds. The effects of different fiber/scaffold mass ratios, fiber mechanical properties and fiber lengths on …

Chitosan Adhesive Films For Photochemical Tissue Bonding, Antonio Lauto, Damia Mawad, Matthew Barton, Sabine C. Piller, Leonardo Longo

Australian Institute for Innovative Materials - Papers

Photochemical tissue bonding (PTB) is a promising sutureless technique for tissue repair. PTB is often achieved by applying a solution of rose bengal (RB) between two tissue edges, which are irradiated by a green laser to crosslink collagen fibers with minimal heat production. In this study, RB has been incorporated in chitosan films to create a novel tissue adhesive that is laser-activated. Materials and Methods. Adhesive films, based on chitosan and containing ∼0.1wt% RB were manufactured and bonded to calf intestine by a solid state laser (wavelength =532nm, Fluence ∼110J/cm2, spot size ∼5 mm). A single-column tensiometer, interfaced with a …

Polyelectrolyte Complex Materials From Chitosan And Gellan Gum, Khairul Anuar Mat Amin

University of Wollongong Thesis Collection 1954-2016

The demand for wound management treatment especially advanced and active wound care products are huge. Polyelectrolyte complex (PEC) materials have been reported as a promising and novel way to develop wound dressings. The research presented in this thesis aimed to utilise the biopolymers chitosan (CH) and gellan gum (GG) in the preparation of PEC films. These films were prepared by dipping free-standing CH and GG films into oppositely charged solutions. Studies on PEC films showed that the mechanical characteristics depend on the solution and film pH, as well as the order of addition of the biopolymers. GG films immersed into …

Synthesis And Spectral Characterization Of A Decavanadate/Chitosan Complex, Violeta Dimitrova Kassabova Zhetcheva, Lilyana Parvanova Pavlova

Turkish Journal of Chemistry

A decavanadate/chitosan complex was synthesized by crosslinking chitosan with decavanadate anions at a pH of 3. The materials were characterized by Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), absorption spectroscopy (UV-Vis), and transmission electron microscopy (TEM). The spectroscopic results indicated that the decavanadate/chitosan complex was successfully obtained as result of an ionic crosslinking of the chitosan with decavanadate anions.

Biopharmaceutical Approaches For Improved Drug Delivery Across Ocular Barriers, Ketan Hippalgaonkar

Electronic Theses and Dissertations

The eye is protected from the external environment by various physiological and anatomical barriers. These barriers through there protective actions drastically diminish the ocular bioavailability of drugs. The corneal epithelium acts as a major barrier towards the permeation of hydrophilic agents, whereas poor aqueous solubility presents a formulation challenge for lipophilic compounds. Additionally, P-glycoprotein (P-gp) expressed on the retinal pigmented epithelium (RPE P-gp) limits the penetration of substrates, in therapeutically relevant concentrations, into the back-of-the-eye.

In the present research, use of penetration enhancers (chitosan, benzalkonium chloride (BAK) and ethylenediaminetetraacetic acid (EDTA)) and formulation approaches (cyclodextrins and solid lipid nanoparticles (SLNs)) …

Nose To Brain Delivery Of Therapeutic Agents, Siva Ram Kiran Vaka

Electronic Theses and Dissertations

The potential treatment approaches for various disorders associated with central nervous system are invasive and do not allow frequent administration. Brain targeting of drugs by intranasal route is a safe and noninvasive method of drug delivery which allows frequent administration and is certainly more patient compliant than the currently folloinvasive methods. In this study, the plausibility of delivering neurotrophins [nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF)], neurotrophinogenic agents (ex: carnosic acid) and antibiotics (ex: cefotaxime) to brain via nose-brain pathway using chitosan as barrier modulating agent was investigated. In vitro permeation studies of fluorescein isothiocyanate dextran (FD40k) …

Supercritical Fluid Aided Microencapsulation Of Dry Powders, Raquel Carvallo

USF Tampa Graduate Theses and Dissertations

Coating of fine particles to produce tailored surface properties is currently a key development for supercritical fluids applications, in different areas such as: pharmaceutical, nutraceutical, cosmetic, agrochemical, electronic and specialty chemistry industries. During the encapsulation process the particles surface can be designed with specific properties by spreading a thin film coating material over the surface of the particles.

Chitosan, a natural polymer, was used in this work as the encapsulant material. Chitosan is biocompatible, biodegradable to normal body constituents, safe, non-toxic, bacteriostatic, anticancerogen, and versatile polymer. These attributes are among the properties that make Chitosan an attractive component of pharmaceutical …

Comparison Of Disk Diffusion, Agar Dilution, And Broth Microdiultion For Antimicrobial Susceptibility Testing Of Five Chitosans, Lin Jiang

LSU Master's Theses

Chitosan is a polysaccharide biopolymer with excellent biocompatibility, biodegradability, and low toxicity, which allows for potential wide applications. Recently, antimicrobial activities of chitosan against foodborne pathogens have been studied; many used disk diffusion to determine the activity. However, this method is unable to obtain minimal inhibitory concentrations (MICs), i.e., not quantitative. The objective of this study was to compare disk diffusion with agar dilution and broth microdilution, two quantitative methods used routinely in clinical laboratories, to determine MICs of chitosan against foodborne pathogens. Five chitosan compounds with molecular weights ranging between 43 and 1,100 kDa were tested against 36 representative …