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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Chitosan microspheres for controlled drug delivery

He, Ping January 1997 (has links)
No description available.
2

Polysaccharide decoration of complexation hydrogel networks for oral protein delivery

Phillips, Margaret Ann 12 October 2011 (has links)
Polysaccharide-decorated complexation hydrogels were investigated for use as oral insulin delivery systems. Several different polysaccharide modifications of poly(methacrylic acid-grafted-ethylene glycol) hydrogels were developed using dextran and pullulan. Polymerizable groups were added to the polysaccharides, dextran and pullulan, by methacrylation. These macromers were then copolymerized with methacrylic and poly(ethylene glycol) to form P(MAA-g-EG-co-Dextran) and P(MAA-g-EG-co-Pullulan) gels using a UV-initiated free radical polymerization. The synthesis of these materials was confirmed using Fourier transform-infrared spectroscopy. The pH-responsive swelling of these systems was investigated using dynamic and equilibrium swelling measurements. Swelling of polysaccharide-modified hydrogels occurred with increasing pH. In acidic conditions, these materials were in a collapsed state while in neutral conditions these materials were swollen. The ability to load insulin into these hydrogels using was demonstrated with loading efficiencies as high as 88% were observed for P(MAA-g-EG-co-Dextran 6000) hydrogel microparticles. Almost zero release of insulin occurred in acidic conditions while an increase in pH was shown to trigger release. The use of dextran and pullulan-modified complexation hydrogels for oral delivery applications was investigated using in vitro cellular viability assays and mucoadhesion experiments. These systems were shown to cause little cytotoxicity to an intestinal epithelium Caco-2 cell model over a range of concentrations as high as 1 mg/ml. The adherence of polysaccharide-modified hydrogels to reconstitituted mucin gels was quantified with the P(MAA-g-EG-co-Dextran 6000) performing the best. Further evaluation of polysaccharide-modified complexation hydrogels for oral insulin delivery was evaluated through in vitro insulin drug transport studies using a mucus-producing Caco-2/HT29-MTX co-culture model. The results showed that the P(MAA-g-EG-co-Dextran 6000) allowed transport of insulin across the cell monolayers and did not adversely affect the integrity of the epithelial monolayer. / text
3

Design, synthesis, characterization, and evaluation of a cationic poly-amido-saccharide towards biocompatible nucleic acid delivery

Balijepalli, Anant Shankar 29 January 2020 (has links)
Carbohydrates are central components of biological systems, with roles ranging from metabolism to immune signaling, and are utilized as antibiotics, anti-coagulants, and biomaterials. Carbohydrate polymers with ionic functionality, such as alginic acid and chitosan, are used in hydrogels, tissue engineering, drug delivery, and as nucleic acid vectors. The clinical translation of polysaccharide biomaterials is hindered by the poor chemical definition, poor batch-to-batch consistency, and demanding purification process of naturally-obtained material. Additionally, there are few synthetic methods yielding enantiopure, water-soluble carbohydrate polymers with high molecular weight. To address the need for translatable carbohydrate biomaterials, our group recently introduced bioinspired Poly-Amido-Saccharides (PASs) as enantiopure, water-soluble, and well- defined carbohydrate polymers. These previously reported PAS polymers, however, mimic polysaccharides with primarily metabolic roles due to the lack of charged functional groups important for biomaterial applications. In this thesis, I describe the synthetic methodology of a regioselectively amine-functionalized β-lactam carbohydrate monomer, the subsequent synthesis of enantiopure, water-soluble amine-functional PASs (AmPAS), an evaluation of AmPAS biocompatibility and mucoadhesivity for pharmaceutical formulations, and the use of AmPAS for biocompatible nanoparticulate delivery of nucleic acids. Protecting group choices and regioselective modification are key to the synthesis of the AmPAS monomer via [2+2] cycloaddition with electron-deficient isocyanates. The results of a combined experimental and theoretical study indicate that bulky protecting groups of the 6’-OH enforce a 5H4 glycal conformation and favorable overlap of ring σC-O* with the glycal allyloxocarbenium system that enhances negative hyperconjugation effects due to electron withdrawing protecting groups. These data inform AmPAS monomer synthesis, where bulky, electron-withdrawing groups are required for regioselective glycal functionalization and intermediate protecting group stability is necessary to obtain cationic, water-soluble AmPAS. These polymers exhibit minimal cytotoxicity and immunogenicity, and, through single molecule force spectroscopy and ex vivo methods, significant mucoadhesivity important for pharmaceutical application. AmPAS are obtained with tunable molecular weight distributions to allow for nanoscale size- and charge-matched supramolecular assemblies with single stranded RNA and DNA oligonucleotides. These nanoparticles are stable in high serum conditions, exhibit high cell uptake, and are shown to successfully deliver anti-miR-21 oligonucleotides to mediate miR-21 knockdown in vitro. These promising results motivate the future application of AmPAS in small molecule and antisense oligonucleotide delivery formulations. / 2022-01-28T00:00:00Z
4

Ophthalmic Biomaterials

Muirhead, Ben 11 1900 (has links)
This thesis will explore, both generally and very specifically, the role of biomaterials in drug delivery and tissue engineering applications. A novel therapeutic conjugate to treat dry eye disease using hyaluronic acid and sulfadiazine was created and tested using a benzalkonium chloride induced dry eye model. Thermoresponsive hydrogels based around poly(n-isopropylacrylamide) were synthesized to create a potential in situ gelling cell scaffold for cell delivery to the subretinal space. Finally, a mucoadhesive micelle was developed as a platform delivery system to increase bioavailability of drug in anterior segment therapeutics. / Thesis / Doctor of Philosophy (PhD)
5

Research on nanodelivery systems for nasal vaccine / Recherche sur les systèmes de nanotransporteurs pour les vaccins nasaux

Le, Minh Quan 25 October 2018 (has links)
L'administration nasale a un grand avantage pour stimuler l'immunité protectrice locale et systémique. Cependant, des systèmes d'administration et des adjuvants sont souvent nécessaires pour améliorer l'efficacité du vaccin intranasal. Nous avons appliqué la technologie des nanoparticules en tant que système universel de délivrance de vaccins contre la grippe dans le projet européen FP7 appelé UniVacFlu.Nous avons évalué différentes nanoparticules (NP) pour rechercher le meilleur nanovecteur. Pour cela, nous avons comparé 5 types de nanoparticules avec différentes charges de surface (anioniques ou cationiques) et diverses compositions internes comme vecteurs potentiels: des liposomes cationiques ou anioniques, des NP de PLGA cationique ou anionique (poly acide lactique co-glycolique) et une NP cationique composée de maltodextrine fonctionnalisée par un agent cationisant avec un coeur de lipides anioniques (NPL). Nous avons d'abord quantifié leur temps de résidence nasale après l'administration nasale chez la souris en utilisant l'imagerie in vivo et les NPL ont montré le plus long temps de résidence. L'endocytose in vitro sur des cellules muqueuses (cellules épithéliales des voies respiratoires, macrophages et cellules dendritiques) en utilisant des nanoparticules marquées a été réalisée par cytométrie de flux et microscopie confocale. Parmi les 5 nanoparticules, les NPL ont été majoritairement captées par 3 lignées cellulaires différentes représentatives d’un épithélium respiratoire et les mécanismes d'endocytose ont été caractérisés. Afin d’évaluer le meilleur vecteur en tant que véhicules, le chargement d'antigènes et la délivrance intracellulaire ont été évalués dans des cellules de la muqueuse des voies respiratoires (cellules épithéliales des voies aériennes, macrophages et cellules dendritiques) par cytométrie de flux. Nous montrons que les NPL sont les meilleurs candidats capables de délivrer la plus grande quantité de protéines dans les cellules. Pris ensemble, notre étude a révélé que parmi 5 nanoparticules, la NPL était le meilleur nanovecteur en termes de temps de résidence nasale, d'endocytose par les cellules et de délivrance de protéines dans l'épithélium des voies respiratoires. Les NPL ont donc été sélectionnées comme nanovecteurs pour le projet UniVac Flu.Les antigènes de la grippe CTA1-3M2e-DD et HA ont été formulés avec les NPL. Le CTA1-3M2e-DD est un antigène chimérique adjuvanté et ciblé. Il est composé de la sous-unité A1 de la toxine du choléra et un épitope conservé du virus grippal A (M2e), ainsi que le dimère de l'analogue synthétique de la protéine A de Staphylococcus aureus (DD) utilisé comme agent de ciblage des lyphocytes B. Pour améliorer l'effet antigénique, l’HA recombinant de H1N1 a été combinée avec CTA1-3M2e-DD. Ces formulations ont été évaluées chez la souris par le consortium UniVacFlu. Les résultats ont montré que CTA1-3M2e-DD et HA chargé dans les NPL formeraient un vaccin intranasal prometteur contre la grippe. Ce travail de thèse montre que les NPL sont des nanovecteurs d’intérêt pour le vaccin nasal. / Nasal administration has great advantage for stimulating the immune system, such as stimulating local and systemic protective immunity. However, delivery systems and adjuvants are often necessary to improve the efficacy of the intranasal vaccine. We applied nanoparticle technology to deliver a universal influenza vaccine via the nasal route in a European FP7 project called UniVacFlu.We evaluated different nanoparticles to search the best nanocarrier for an intranasal vaccine. Here we compared 5 types of nanoparticles with different surface charges (anionic or cationic) and various inner compositions as potential vectors: cationic and anionic liposomes, cationic and anionic PLGA (Poly Lactic co-Glycolic Acid) nanoparticles and zwitterionic maltodextrin nanoparticles (cationic surface with an anionic lipid core: NPL). We first quantified their nasal residence time after nasal administration in mice using in vivo live imaging and NPL showed the longest residence time. In vitro endocytosis on mucosal cells (airway epithelial cells, macrophages and dendritic cells) using labeled nanoparticles were performed by flow cytometry and confocal microscopy. Among the 5 nanoparticles, NPL were taken up to the greatest extent by the 3 different cell lines and the endocytosis mechanisms of NPL were characterized. In order to compare different nanoparticles as vaccine carriers, antigen loading and cell delivery were evaluated. In this study, we compared the loading and delivery of labeling ovalbumin with airway mucosa cells (airway epithelial cells, macrophages and dendritic cells) by flow cytometry. Our data showed that NPL were the best candidate that can payload with highest amount of protein and eventually the most efficient cellular protein delivery capacity. Taken together, our study revealed that among 5 nanoparticles, NPL were the best nanocarrier that own longer nasal residence time, efficiently uptake and deliver protein into airway epithelium. NPL were then selected as nanocarrier for the UniVac Flu project.The flu antigens CTA1-3M2e-DD and HA were formulated with NPL. The CTA1-3M2e-DD is an adjuvanted antigen composed of the A1 subunit of cholera toxin and a conserved epitope of influenza A virus (M2e), as well as the dimer of the synthetic analogue of Staphylococcus aureus protein A (DD) used to target B cells. To improve antigenic effect, recombinant HA from H1N1 was combined with CTA1-3M2e-DD. These formulations were evaluated in mice by the UniVacFlu consortium. We observed that CTA1-3M2e-DD and HA loaded into NPL could be a promising universal intranasal influenza vaccine.
6

Efeitos da formulação mucoadesiva com extrato de Curcuma longa L. em animais portadores de mucosite intestinal induzida por 5-fluorouracil

Santos Filho, Edvande Xavier dos 20 March 2014 (has links)
Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-09-22T17:08:11Z No. of bitstreams: 2 Santos Filho, Edvande-2014-dissertação.pdf: 3465269 bytes, checksum: fd50a85f70b6b596e0c5c4fb5fd18cb9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-09-22T18:45:16Z (GMT) No. of bitstreams: 2 Santos Filho, Edvande-2014-dissertação.pdf: 3465269 bytes, checksum: fd50a85f70b6b596e0c5c4fb5fd18cb9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-22T18:45:16Z (GMT). No. of bitstreams: 2 Santos Filho, Edvande-2014-dissertação.pdf: 3465269 bytes, checksum: fd50a85f70b6b596e0c5c4fb5fd18cb9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-03-20 / Introduction: Intestinal mucositis is a frequent limiting factor in antineoplastic therapy. There is no truly effective treatment targeted to cure this side effect. Curcuma longa L. has been reported to have antioxidant, antitumor and anti-inflammatory properties. Objective: This study aimed to evaluate the effects of a mucoadhesive formulation with Curcuma longa L. extract (MCL) in mice bearing intestinal mucositis induced by 5-FU. Methods: Swiss male adult mice (35-40g) were randomly allocated into three experimental groups of 5 animals each: control (mucoadhesive formulation 0.6mL/animal, via gavage, from day 1-6); exposed to 5-fluorouracil (5-FU 200mg/kg, i.p., in days 4-6); treated prophylactically and throughout mucositis with FMCL and exposed to 5-FU (MCL 15mg/kg, via gavage, from day 1-6, plus 5-FU 200mg/kg, i.p., in days 4-6). In the 7th day, animals were anesthetized by xylazine-ketamine followed by cervical dislocation. Duodenal samples, 10 cm after pyloric sphincter were removed to perform the essays. The parameters evaluated were: body weight assessment, morphometrics and histo-pathological analysis, apoptosis (p53/Bax, Bcl-2), cell proliferation (Ki-67), myelo-peroxidase (MPO) and malondialdehyde (MDA). Results: 5-FU induced intestinal mucositis characterized by villus shortening, crypt deepening, intense inflammatory infiltration, vacuolization and mucosal edema. Besides, 5-FU induced severe mice body mass reduction, apoptosis in cells of villus and crypts (p<0.001), increase in MPO activity and MDA formation (p<0.05), when compared to the control group. Treatment with MCL attenuated body mass loss, protected intestinal mucosa from villus shortening and crypt deepening, decrease MPO activity and MDA formation (p<0.05). In this group of animals was also observed high expression of the cell proliferation marker Ki-67 in epithelial cells lining of villus and crypts. Conclusion: Our data confirm the therapeutic potential of MCL for the treatment of intestinal mucositis in mice. Further studies are needed to assess this formulation potential for human use. / Introdução: A mucosite intestinal é um dos efeitos adversos limitantes das terapias antineoplásicas. Não existe tratamento realmente efetivo direcionado a cura deste efeito colateral grave. A Curcuma longa L. tem sido proposta como candidata ao tratamento de várias doenças por possuir propriedades antioxidante, antitumoral e anti-inflamatória. Objetivo: Este estudo objetivou avaliar os efeitos da formulação mucoadesiva com extrato de Curcuma longa L. (FMCL) em animais portadores de mucosite intestinal induzida por 5-FU. Métodos: Camundongos Swiss adultos, machos (35-40g) foram aleatoriamente alocados em três grupos experimentais de 5 animais cada: [1] controle (formulação mucoadesiva 0.6mL/animal, via gavagem, do dia 1-6); [2] exposto ao 5-fluorouracil (5-FU 200mg/kg, i.p., dos dias 4-6), [3] tratado profilaticamente e ao curso da mucosite com FMCL e exposto ao 5-FU (FMCL 15mg/kg, via gavagem dos dias 1-6, mais 5-FU 200mg/kg, i.p., dos dias 4-6). No sétimo dia, os animais foram anestesiados por xilazina-ketamina seguido por deslocamento cervical. Amostras de duodeno, 10 cm após o esfíncter pilórico, foram coletadas para realização dos ensaios. Os parâmetros avaliados foram: avaliação de massa corporal, análise morfométrica e histopatológica, apoptose (p53/Bax; Bcl-2), proliferação celular (Ki-67), mieloperoxidase (MPO) e malondialdeído (MDA) Resultados: A administração de 5-FU induziu mucosite intestinal caracterizada por encurtamento das vilosidades, aprofundamento das criptas, intenso infiltrado infla-matório, vacuolização e edema na mucosa. Além disso, o 5-FU induziu grave redução de massa corporal nos camundongos e apoptose nas células das vilosida-des e criptas, quando comparado ao grupo controle (p<0,001). Foi observado ainda aumento na atividade de MPO e formação de MDA, quando comparado ao grupo controle (p<0,05). Por outro lado, o tratamento com a FMCL atenuou a perda de massa corporal dos animais com mucosite. Ademais, protegeu a mucosa intestinal da redução no tamanho das vilosidades e criptas induzidas pelo 5-FU. Neste grupo de animais foi observado ainda aumento na expressão do marcador de proliferação celular Ki-67 nas células epiteliais de revestimento das vilosidades e criptas intestinais. O tratamento também diminuiu significantemente a atividade de MPO e formação de MDA (p<0,05). Conclusão: Os dados confirmam o potencial terapêutico da FMCL no tratamento da mucosite intestinal em camundongos. Estudos adicionais são necessários para que esta formulação possa se tornar uma alternativa segura para uso em seres humanos.
7

MUCOADHESIVE FILMS FOR TREATMENT OF LOCAL ORAL DISORDERS: DEVELOPMENT, CHARACTERIZATION AND <em>IN VIVO</em> TESTING

Ramineni, Sandeep K 01 January 2014 (has links)
Mucoadhesive drug delivery systems which are being used from 1980’s to avoid first pass metabolism of drugs, commercially exist for only systemic drug delivery with fast erosion times (15-60 min), that may not be appropriate for local oral disorders. The goal of this research was to develop and characterize mucoadhesive films with flexibility of carrying different drugs and proteins and provide sustained release for local treatment of oral disorders. Mucoadhesive films composed of polyvinylpyrrolidone (PVP) and carboxymethlycellulose (CMC) were formulated with imiquimod, an immune response modifier. Problems such as solubilization of imiquimod to increase drug loading, uniformity in films and total amount of drug released into supernatants were addressed by use of acetate buffer after investigating multiple methods. Subsequently, other relevant properties of mucoadhesive systems, such as adhesion (shear, pull-off), tensile properties, swelling profiles, transport kinetics, and subsequent changes in release profiles as a function of film composition were characterized. The potential of the system for local retention of imiquimod, determined in oral mucosa of hamsters showed time dependent decrease in imiquimod amount through 12 hours, with no traces of drug in blood. Further testing in humans revealed that the residence time of the mucoadhesive films depended on the application site, increasing in the order of tongue < cheek < gingiva. In parallel, mucoadhesive films loaded with epidermal growth factor (EGF) were developed to promote treatment of oral mucosal wounds. Bioactivity was tested in vitro on buccal tissues by creating a wound followed by application of films. Although EGF-loaded films did not accelerate wound healing, but rather elicited a hyperparakeratotic response. In vitro buccal tissues may not be appropriate for testing the effects of EGF in wound healing without incorporation of other biochemical factors. Overall, a mucoadhesive system capable of delivering bioactive small molecules and proteins in sustained manner was developed in this work. A thorough understanding of the system properties was achieved to further tune for future applications. In vitro studies and in vivo studies in hamsters and humans clearly showed the potential and usefulness of the system to translate in to clinic for treatment of oral precancerous lesions.
8

Adhezivní a reologické vlastnosti směsí na bázi chitosanu / Adhesive and rheological properties of chitosan-based mixtures

Korpasová, Marie January 2020 (has links)
CHARLES UNIVERSITY IN PRAGUE Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Name and surname: Marie Korpasová Title of diploma thesis: Adhesive and rheological properties of mixtures based on chitosan Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Diploma thesis deals with evaluation of rheological and adhesive properties of compounds for matrix tablets formulation, based on Chitosan with addition of retardant compound. The retardant compound consists of Sodium Alginate and Hypromellose in concentrations of 30 %, 40 % and 50 %. Theoretical part describes Chitosan, Sodium Alginate and Hypromellose. As next is division of matrix tablets. Theoretically is also described evaluation of rotational, oscillational and adhesive testing which was used in practical part. From viscosity curves can be seen, that viscosity is decreasing with increasing stress. Viscosity increases with increasing concentration of Sodium Alginate and Hypromellose. Oscillational testing is better for gel characterization, because it provides lower stress on test samples. Samples of given compound were prepared by hydrating with phosphate buffer of pH 6,8. Coefficient of consistency K and index flow rate n characterize rheological behaviour of gels. Viscoelastic compounds behave like solids with plastic...
9

Reologické chování směsí pro lyofilizaci / Rheological behaviour of mixtures for freeze-drying

Vavřich, Dominik January 2020 (has links)
CHARLES UNIVERSITY Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Name of author: Dominik Vavřich Title of diploma thesis: Rheological behaviour of mixtures for freeze-drying Supervisor: PharmDr. Eva Šnejdrová, Ph.D. The diploma thesis deals with the evaluation of rheological properties of aqueous dispersions of fish gelatin and carrageenans intended for lyophilization. Theoretical part of this work is dedicated to the characterization of fish gelatin and carrageenans which were used for preparation of the mixtures in experimental part of this work. Characterization of an oral cavity from an application of medicaments point of view and an orally disintegrating tablets of the medicine with a focus on the lyophilized tablets are also presented. Mixtures of the fish gelatin and the carrageenans were prepared in the experimental part of the work. Their rheological behaviour employing an absolute rotational rheometer Kinexus Pro+ was measured and evaluated. Also, the testing of the rheological characteristics of these materials transformed into the freeze-dried tablets was performed. Nonlinear viscous curves were obtained, and they were mathematically evaluated by the Power law model. Pseudoplastic behaviour of the mixtures can be derived from the results of acquired...
10

Obtenção de gel mucoadesivo de nistatina para o tratamento da candidíase oral. Desenvolvimento e caracterização de dispersões sólidas de nistatina / Mucoadhesive gel obtaining nystatin for the treatment of oral candidiasis. Development and characterization of solid dispersions of nystatin

Aguiar, Michelle Maria Gonçalves Barão de 04 April 2016 (has links)
A nistatina (NYS) é o fármaco de primeira escolha no tratamento da candidíase oral, que frequentemente acomete mais os indivíduos imunocomprometidos e pacientes com outras desordens (diabetes não tratada, neoplasias, imunodeficiências). No mercado brasileiro, a NYS é encontrada na forma de suspensão oral aquosa, onde o procedimento para sua administração consiste em bochechar o medicamento. Apesar de haver a indicação de que se mantenha o contato direto entre fármaco e a mucosa oral, na qual se encontra a Candida spp., o que aumentaria expressivamente o sucesso terapêutico, a suspensão não apresenta tal propriedade. Assim, a NYS que é fármaco com ação efetiva contra a candidíase oral, é considerada pertencente à Classe IV do Sistema de Classificação Biofarmacêutica, ou seja, apresenta baixa solubilidade e baixa permeabilidade. A baixa solubilidade pode comprometer sua disponibilidade na cavidade oral, e consequentemente, sua ação farmacológica. Diante desse quadro, o objetivo do presente trabalho foi o desenvolvimento de dispersões sólidas de NYS para o tratamento da candidíase oral, e sua posterior incorporação em gel mucoadesivo oral, favorecendo a formulação no local de ação. As dispersões sólidas são sistemas farmacêuticos, onde um fármaco pouco solúvel em água encontra-se dispersado em um carreador, no estado sólido. Os carreadores normalmente são hidrofílicos, o que permite que esses sistemas sejam empregados para aumentar a solubilidade aquosa do fármaco. Assim, foram desenvolvidas as dispersões sólidas de NYS, pelo método de eliminação do solvente, empregando como carreadores, lactose, HPMC, poloxamer 407 e poloxamer 188. Essas foram submetidas à caracterização por análise térmica, usando os ensaios de calorimetria exploratória diferencial (DSC) e termogravimetria/termogravimetria derivada (TG/DTG). Dentre essas dispersões sólidas, aquelas que se mostraram com comportamento térmico sugerindo a formação de um novo \"sistema\", foram analisadas por meio de ensaio de solubilidade. Dessa forma, a formulação NYS DS G2 (49) se destacou, pois apresentou maior solubilidade em água (4,484 mg/mL); em pH 5,5 (4,249 mg/mL) e em pH 7,0 (4,293 mg/mL), ou seja, houve um aumento de 1,426 vezes em água; 4,227 vezes em pH 5,5; e 2,743 vezes em pH 7,0. Essa formulação foi, por fim avaliada por difração de raio-X e espectroscopia de infravermelho com transformada de Fourier, técnicas que corroboraram com a análise térmica quanto à indicação de formação da dispersão sólida. Por sua vez, essa dispersão sólida foi incorporada em 4 bases de géis mucoadesivos de carbopol ® 934 PNF, alterando apenas a concentração do polímero (0,5; 1,0; 1,5; 2,0 %p/p). Foi observado que a liberação de NYS DS G2 (49) foi superior, quando comparada à liberação de NYS MP a partir do gel, e através do ensaio de mucoadesão, percebeu-se que os géis desenvolvidos apresentaram propriedades mucoadesivas compatíveis com relatos na literatura, independentemente da quantidade de carbopol ® empregada. As características reológicas foram distintas, e foi observado que as formulações Gel A e Gel B, que possuem menor quantidade de polímero, tiverem um indicativo de comportamento de fluido newtoniano, diferente dos demais, o que pode não ser desejado para esse tipo de forma farmacêutica tópica e semi-sólida. Ao final desse trabalho, pode-se concluir que foi possível desenvolver um sistema farmacêutico na forma de dispersão sólida com maior solubilidade que a NYS pura, e sua incorporação em uma forma farmacêutica mucoadesiva, e que a liberação da NYS na forma DS foi muito superior que o fármaco na forma \"convencional\", o que permite que a NYS esteja mais disponível na cavidade oral, e também junto à mucosa bucal, o que levaria a efeito farmacológico mais efetivo do antifúngico. / Nystatin (NYS) is the drug of first choice in the treatment of oral candidiasis that most often affect immunocompromised individuals, and patients with other disorders. In the Brazilian market, NYS is found in the form of aqueous oral suspension, a medication used in the form of mouthwash. Although there is an indication to maintain direct contact between the drug and the oral mucosa, where Candida spp. is found, as well as where therapeutic success would significantly be increased, the suspension has no such property. Thus, the NYS is an effective drug against oral candidiasis, and belongs to Class IV of the Biopharmaceutical Classification System, it has low solubility and low permeability. The low solubility can compromise its availability in the oral cavity, and consequently, its pharmacological action. Given this situation, the objective of this work was the development of solid dispersions of NYS for the treatment of oral candidiasis, and its subsequent incorporation into oral mucoadhesive gel, in order to facilitate its action. Solid dispersions are pharmaceutical systems, in which a solid drug poorly soluble in water is dispersed in a carrier. These carriers are usually hydrophilic, and this allows the systems to be employed in order to increase the aqueous solubility of the drug. Thus, the solid NYS dispersions were developed by the solvent evaporation method, employing lactose, HPMC, poloxamer 407 and poloxamer 188 as carrier. These samples were subjected to characterization by thermal analysis, using differential scanning calorimetry (DSC) and thermogravimetry / derivative thermogravimetry (TG / DTG). Among these solid dispersions, those samples which showed a specific thermal behavior suggesting the formation of new \"system\" were analyzed by solubility test. Thus, the NYS DS G2 formulation (49) stood out, once it showed greater solubility in water (4.484 mg/mL); at pH 5.5 (4.249 mg/mL) and pH 7.0 (4.293 mg/mL), in other words, an increase of 1,426 times in water; 4,227 times at pH 5.5; and 2,743 times at pH 7.0. This formulation was finally evaluated by X-ray diffraction, infrared spectroscopy with Fourier transform, techniques that corroborate the thermal analysis, indicating the formation of the solid dispersion. On the other hand, this solid dispersion was incorporated into 4 Carbopol ® 934 PNF mucoadhesive gels, with a variation of the polymer concentration. It was observed that NYS is improved of delivery from the gels, employing mucoadhesion test, and was also observed that the gels have mucoadhesive properties consistent with reports in the literature. However, the rheological characteristics are different, and it was observed that the Gel A and Gel B formulations, which has a lower amount of polymer behaved as a Newtonian fluid, which may not be desired for this type of topical gel. As conclusion, it was possible to develop a pharmaceutical system in the form of solid dispersion with greater solubility than the pure NYS, and their incorporation in a mucoadhesive dosage form and the release of NYS as DS was far superior wherein the drug in the \"conventional\" manner, which allows the NYS is longer available in the oral cavity, and also adjacent to the buccal mucosa, leading to more effective pharmacological effect of the antifungal agent.

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