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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.
51

香港中藥飮片的炮製加工特色研究

張楝健, 01 January 2010 (has links)
No description available.
52

SCF - Engineered powders for delivery of budesonide from passive DPI devices

York, Peter, Lobo, J.M., Palakodaty, S., Schiavone, H., Clark, A., Tzannis, S.T. January 2005 (has links)
No / The objective of this study was to develop SEDS-engineered budesonide particles suitable for dry powder inhalation delivery and to evaluate their aerosol performance across a range of passive dry powder inhalers (DPI). SEDS budesonide powders were manufactured in Nektar's SCF manufacturing plant and compared to the micronized drug and commercial powder (Pulmicort Turbuhaler, AstraZeneca). Aerosol performance was evaluated by determining emitted dose (ED) by a variation of the USP method and fine particle fraction (FPF) using Andersen cascade impaction. The SCF powder dispersed best in the Turbospin and Eclipse devices, exhibiting high EDs (70%-80%) and relatively low variability (RSD 8%-13%). Regardless of the device, the SEDS material outperformed both the micronized drug and the commercial powder, while exhibiting good batch-to-batch reproducibility (RSD <5%). All powders exhibited flow rate-dependent ED, albeit for the SEDS material it was minimized at reduced fill weights. This was attributed to inadequate and variable powder clearance from the capsules at low inspiratory flow rates, which was more pronounced in the Eclipse and Cyclohaler. The results demonstrate that SEDS is an attractive particle-engineering process that may enhance pulmonary performance of budesonide and possibly facilitate development of other small molecule pulmonary products in passive DPI.
53

Supercritical fluid processing of proteins: lysozyme precipitation from aqueous solution.

Moshashaee, S., Bisrat, M., Forbes, Robert T., Quinn, Ellis A., Nyqvist, H., York, Peter January 2003 (has links)
No / Aqueous solutions of hen egg lysozyme (3% w/v) were dispersed and precipitated by a homogenous mixture of supercritical carbon dioxide-ethanol using the Solution Enhanced Dispersion by Supercritical fluid (SEDS) process. The effects of different working conditions, such as temperature, pressure and the flow rates of the solution and ethanol, on the particle-formation process were studied The morphology, particle size and size distribution and biological activity of the protein were determined The precipitates were examined with high-sensitivity differential scanning calorimetry (HSDSC) and high-performance cation-exchange chromatography Particle size measurements showed the precipitates to be aggregates with primary particles of size 1-5 ¿m. The similarity of HSDSC data for unprocessed and processed samples indicated that the different physical forces that stabilise the native form of lysozyme are unchanged after SEDS processing. From FT-Raman spectroscopic studies secondary structural changes were observed in certain SEDS-produced lysozyme, with most processed samples displaying a slightly more disordered secondary structure than the unprocessed sample However, SEDS samples produced at 200 bar and 40 C exhibited negligible disturbance Thus the SEDS process utilising aqueous solution was able to bring about size reduction of lysozyme with minimal loss of biological activity.
54

Determination of the permeability of biological membranes to various chemical markers, including anti-HIV drugs

Pretorius, Erina 12 1900 (has links)
Thesis (PhD (Pathology. Medical Microbiology))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Due to modern high-throughput technologies, large numbers of compounds are produced by parallel synthesis and combinatorial chemistry. The pharmaceutical industry therefore requires rapid and accurate methods to screen new drugs leads for membrane permeability potential in the early stages of drug discovery. Around 50 % of all investigational new drugs fail in pre-clinical and clinical phases of development due to inadequate absorption/permeation, distribution, metabolism, excretion and/or unacceptable toxicity. This may be decreased by applying in vitro screening methods early in the discovery process. Reliable in vitro models can be applied to determine permeation of the test compounds, which will help avoid the wasting of valuable resources for the development of drugs that are destined to fail in preclinical and clinical phases due to insufficient permeability properties. It is important to decide as early as possible on the most promising compound and physical formulation for the intended route of administration. With awareness of the increasing importance of in vitro models in the investigations of the permeability properties of drug compounds, this research project was specifically devoted to determine the suitability of our in vitro model to evaluate and predict drug permeability. A continuous flow-through diffusion system was employed to evaluate the permeability of nine different compounds/drugs with different chemical properties, across three biological membranes. The biological membranes chosen for the present study were human vaginal mucosa, human skin tissue and human small intestine mucosa. The continuous flow-through diffusion system was furthermore utilised to investigate the effects of de-epithelialisation of mucosal surfaces, chemical enhancers, temperature, permeant concentration and formulation on the permeability of the test compounds/drugs. The in vitro permeability information and data from the flow-through diffusion model were compared to in vitro and in vivo literature studies and drug profile. An in vitro model that is able to reliably predict in vivo data will shorten the drug development period, economise resources and may potentially lead to improved product quality. In this thesis research results are reported on the permeability of the mentioned biological membranes to the various chemical markers, including anti-HIV (human immunodeficiency virus) drugs. The permeability studies will be discussed in three sections: vaginal mucosa, skin tissue, small intestine mucosa. The results of the vaginal permeability studies showed that the three peptides (MEA- 5, MDY-19 and PCI) readily penetrated the vaginal mucosa. MDY-19 had a higher flux rate than MEA-5, commensurate with its smaller molecular size (weight). The surfactant enhanced the flux rate of MDY-19 approximately 1.3 times and decreased the lag time of the peptide. Removal of the vaginal epithelium increased the flux rates of the peptides across the mucosa and may have implications for a more rapid uptake of these and other microbicides in vivo. The permeability of 1 mM MDY-19 and PCI at 37 °C were significantly (p<0.05) higher than at 20 °C. At 37 °C the AUCs of the overall mean flux values of MDY-19 and PCI increased with concentration according to well-established diffusion theory. The experiments on the permeability of different terbinafine hydrochloride formulations through human skin demonstrated that the terbinafine hydrochloride formulations used in this study, readily diffused into the skin tissue. However, no flux values for any of the terbinafine hydrochloride formulations through the skin into the acceptor fluid were found. The mean terbinafine concentrations in the skin after 24 h exposure to the three commercial, terbinafine hydrochloride formulations were 3.589, 1.590 and 4.219 μg/ml respectively. The mean terbinafine concentration in the skin exposed to the 10 mg/ml PBS/Methanol solution was higher than those from the three commercial formulations. The results of the temperature study demonstrated that an increase of 5 ºC caused a significant increase in flux values of tritiated water across skin. The flux values for tritiated water across skin at 37 ºC were on average double those at a temperature of 32 ºC. The permeability of excised human small intestine mucosa to different oral dosage drugs was investigated over a 24 h period. The four drugs selected were zidovudine, propranolol hydrochloride, didanosine and enalapril maleate. They were selected as representative model compounds of drug classes 1 (high solubility, high permeability) and 3 (high solubility, low permeability) according to the Biopharmaceutics Classification System. The flux rates of the four chosen test drugs were influenced by the length of the experiment. Between the time periods 2-4 h and 4-6 h, zidovudine’s mean flux values across small intestine tissue were respectively 1.8 and 2.0 times higher than didanosine and 2.3 and 2.2 times higher than enalapril. Propranolol’s mean flux values were respectively 1.2 and 1.4 times higher than didanosine and 1.6 higher than enalapril during both the 2-4 and 4-6 h time periods. Between both the time periods 2-4 and 4-6 h AZT’s mean flux values were 1.4 times higher than propranolol and didanosine’s mean flux values were respectively 1.3 and 1.1 times higher than enalapril during the mentioned time periods. Class 1 drugs showed a significantly higher flux rate across the jejunal mucosa compared to the class 3 drugs and these results are in line with their Biopharmaceutics Classification System classification. The in vitro model has proved to be reliable to predict permeability of class 1 and 3 drugs and also showed correlation with human in vivo data. It seems that the in vitro flow-through diffusion model used in the present study have the potential to overcome some of the problems and limitations demonstrated by other in vitro techniques and may potentially serve as a future tool for pharmaceutical companies to predict the diffusion characteristics of new drugs and different formulations, across different biological membranes. Furthermore, it may serve as a prospective method for assessing the bioequivalence of alternative (generic) vehicles or formulations containing the same drug/compound. / AFRIKAANSE OPSOMMING: As gevolg van moderne hoë spoed tegnologie kan groot hoeveelhede middels vervaardig word deur ooreenkomende sintese en kombinasieleer chemie. Die farmaseutiese industrie benodig dus vinnige en akkurate metodes om nuwe geneesmiddels te evalueer t.o.v. membraan deurlaatbaarheid. Hierdie evaluasie moet verkieslik so vroeg moontlik in die geneesmiddel se ontwikkelingsproses geskied. Ongeveer 50 % van alle potensiële geneesmiddels misluk in pre-kliniese en kliniese fases van geneesmiddelontwikkeling. Die mislukte pogings kan toegskryf word aan onvoldoende absorbsie/deurlaatbaarheid, distribusie, metabolisme, ekskresie en/of onaanvaarbare middel toksisiteit. Dit is daarom belangrik om so vroeg moontlik in die geneesmiddelontwikkelingsproses te besluit op die mees belowende middel, asook die geskikte formulasie vir die spesifieke roete van toediening van die middel. Die farmaseutiese industrie benodig tans in vitro modelle met die potensiaal om die deurlaatbaarheid van geneesmiddels te bepaal en te voorspel. Betroubare in vitro modelle kan aangewend word om die deurlaatbaarheid van potensiële geneesmiddels te toets. Sodoende sal die onnodige uitgawes op die ontwikkkeling van geneesmiddels wat in elk geval later gaan faal in pre-kliniese en kliniese fases van geneesmiddelproewe a.g.v. deurlaatbaarheidseienskappe, vermy word. Hierdie navorsingsprojek was dus spesifiek onderneem om die waarde en toepaslikheid van ‘n in vitro deurlopende-vloei perfusie model te ondersoek. Die model se potensiaal om geneesmiddels se deurlaatbaarheid en absorpsie te voorspel was geëvalueer. Die deurlopende-vloei perfusie apparaat was gebruik om die deurlaatbaarheidsvloede van drie verskillende biologiese membrane t.o.v. nege chemiese stowwe (MEA-5, MDY-19, PCI, terbinafien hidrochloried, getritieerde water, zidovudien, propranolol, hidrochloried, didanosien, enalapril maleaat) te bepaal. Die drie biologiese membrane wat gebruik was, was vaginale weefsel, vel en klein intestinale weefsel. Al drie weefsel tipes was van menslike oorsprong. Die deurlopende-vloei perfusie apparaat was ook gebruik om die effek wat verwydering van die mukosa se epiteellaag op deurlaatbaarheidsvloede het, te ondersoek. Verder was navorsing gedoen op die effek van temperatuur en die konsentrasie en formulasie van die toetsmiddels op hulle diffusie vloedwaardes. Daar was ook gekyk na die invloed van ander chemiese stowwe op die toetsmiddels se diffusie vloedwaardes. Die in vitro deurlaatbaarheidsinformasie en -gegewens was vergelyk met ander in vitro en in vivo literatuurstudies en geneesmiddel databasisse. ‘n In vitro model wat in staat is om in vivo resultate betroubaar te voorspel, het die potensiaal om die tyd wat dit neem om geneesmiddels te ontwikkel, te verkort, finansiële uitgawes te besnoei en om geneesmiddelkwaliteit te verseker. In die tesis word dan die resultate gerapporteer van die deurlaatbaarheidsvloede van die verskillende tipes weefsel ten op sigte van verskeie chemiese stowwe, insluitende anti-MIV (menslike immuniteitsgebreksvirus) middels. Die deurlaatbaarheidstudies word bespreek in drie afdelings: vaginale mukosa, vel en klein intestinale mukosa. Die resultate van die deurlaatbaarheidstudies op die vaginale weefsel dui daarop dat die drie peptiede (MEA-5, MDY-19 and PCI) die vaginale mukosa goed penetreer. Soos verwag, het MDY-19 hoër diffusie vloedwaardes as MEA-5 gehad. Dit kan toegeskryf word aan MDY-19 se kleiner molekulere grootte (gewig). Surfaktant het die diffusie vloedwaardes van MDY-19 1.3 keer vergroot en het ook die tyd na vaste vlak verminder. Die verwydering van die vaginale epiteel het die diffusie vloedwaardes van die peptiede verhoog en mag dus dui op die vinniger opname van peptiede en moontlike ander mikrobisiede in vivo, wanneer die belyning van die epiteel onderbreek. Die deurlaatbaarheid van 1 mM MDY-19 en PCI by 37 °C was satisties beduidend (p<0.05) hoer as teem 20 °C. Die area onder die kurwe (AOK) van die gemiddelde vloedwaardes van MDY-19 en PCI by 37 °C, het toegeneem met ‘n toename in die konsentrasie van hierdie peptiede. Die toename vloedwaardes ondersteun dus die alombekende diffusie teorie. Die transdermale diffusie eksperimente van verskillende terbinafien formulasies het getoon dat terbinafien geredelik vrygestel word vanuit hierdie formulasies na die vel. Geen terbinafien vloedwaardes, van enige van die formulasies, was egter gevind in die ontvangselle van die deurlopende-vloei perfusie apparaat nie. Die gemiddelde terbinafien konsentrasies in die vel na 24 h se blootstelling aan drie kommersiële terbinafien hidrochloried formulasies was onderskeidelik 3.589, 1.590 en 4.219 μg/ml. Die gemiddelde terbinafien konsentrasie in die vel wat aan 10 mg/ml PBS/metanol blootgestel was, was hoër as die konsentrasies in die vel wat aan die drie kommersiële formulasies blootgestel was. Die resultate van die temperatuurstudie op vel het aangetoon dat ‘n temperatuur toename van 5 ºC ‘n statisties beduidende toename in vloedwaardes van getritieerde water oor vel veroorsaak. Die vloedwaardes van die getritieerde water oor vel teen ‘n temperatuur van 37 ºC was gemiddeld dubbeld so veel as teen 32 ºC. Die deurlaatbaarheidsvloede van klein intestinale mukosa ten opsigte van verskillende geneesmiddels (wat oraal toegedien word) was ondersoek gedurende ‘n 24 h eksperiment. Die vier geneesmiddels wat gebruik was, was zidovudine, propranolol hidrochloried, didanosien en enalapril maleaat. Hierdie geneesmiddels is verteenwoordigers van die Biofarmaseutiese Klassifikasie Sisteem se klas 1 (hoë oplosbaarheid, hoë deurlaatbaarheid) en klas 3 (hoë oplosbaarheid, lae deurlaatbaarheid) geneesmiddels. Die vloedwaardes van die vier geneesmiddels het gewissel na aanleiding van die tydsverloop in die eksperiment. Zidovudien se gemiddelde vloedwaardes tussen 2-4 en 4-6 h was onderskeidelik 1.8 en 2.0 keer hoër as didanosien se gemiddelde vloedwaardes vir hierdie tyd periodes en onderskeidelik 2.3 en 2.2 keer hoër as enalapril se gemiddelde vloedwaardes. Tydens hierdie selfde periodes was propranolol se gemiddelde vloedwaardes 1.2 en 1.4 keer hoër as didanosien en vir beide periods 1.6 keer hoër as enalapril se gemiddelde vloedwaardes. Gedurende beide genoemde tyd periodes was zidovudien se gemiddelde vloedwaardes 1.4 keer hoer as propranolol en didanosien se gemiddelde vloedwaardes was onderskeidelik 1.3 en 1.1 keer hoër as enalapril tydens 2-4 en 4-6 h. Die klas 1 geneesmiddels het statisties beduidende hoër vloedwaardes gehad as die klas 3 geneesmiddels. Hierdie resultate stem ooreen met die geneesmiddels se Biofarmaseutiese Klassifikasie Sisteem klassifikasie. Dit wil dus voorkom asof die in vitro model wat gebruik was in die studie, gebruik kan word om die deurlaatbaarheidsvloede van klas 1 en 3 te voorspel. Die resultate van hierdie studie stem ooreen met ander in vivo studies. Dit wil voorkom asof die in vitro deurlopende-vloei perfusie apparaat die potensiaal het om sommige van die probleme en tekortkominge van ander in vitro modelle te oorkom en dat dit moontlik die potensiaal het om die diffusie-eienskappe van nuwe geneesmiddels en verskillende formulasies oor verskillende biologiese membrane te voorspel. Die model kan verder moontlik dien as ‘n potensiële toestel om biogelykbaarheid van alternatiewe (generiese) formulasies, wat dieselfde geneesmiddel/chemiese stof bevat, te bepaal.
55

Síntese e avaliações físico-químicas de quitosanas quimicamente modificadas pela inserção de radicais de anidrido succínico / Synthesis and physico-chemical evaluations of chitosan chemically modified by the insertion of succinic anhydride radicals

Karine Gargioni Pereira Correa de Mello 01 September 2005 (has links)
A N-succinil-quitosana é um derivado quimicamente modificado do polímero quitosana. A inserção de radicais de anidrido succínico nas aminas protonadas presentes ao longo da cadeia do polímero quitosana, conferem diferentes características físico-químicas à molécula de quitosana. Esta modificação química possibilitou à quitosana, solubilidade em pHs que variam do ácido (2.0) até alcalino (14.0). Estas propriedades são atribuídas ao alongamento da cadeia alquílica, que afasta a ponte hidrofílica da cadeia fechada da D-glicosamina, facilitando o acesso da água, a qual irá estabelecer uma interação mais forte com a molécula de quitosana. Esta propriedade não está presente em amostras de quitosana pura, a qual sabe-se que solubiliza-se apenas em pHs abaixo de 5.5. / The N-succinil-chitosan is a chemically modified derivative of the biopolymer chitosan. The succinic anhydride attached to the free amino groups presented along the chitosan\'s polymer chain imparts to the molecule different physicochemical properties not exhibited before the modification. These chemical modifications enhance chitosan\'s solubility in slightly acid, neutral and alkaline media. These properties are related to the long alkyllic chains attached to hydrophilic parts. In this case the hydrophilic part of D-¬glucosamine promotes stronger interactions with the water molecules, and consequently, enhances the solubility of the chitosan polymer. It is worthy mentioning that non-modified free chitosan is soluble only in acidic medium (pH &#8804;5.5).
56

Proposição de nova rota de síntese do megazol / Proposition new synthesis route of megazol

Amaro, Cecilia Rodrigues de Silva 13 January 2004 (has links)
Em 1968, um composto do tipo 5-nitroimidazol, o megazol, foi sintetizado por Berkelhammer e Asato e demonstrou largo espectro de ação biológica. Em 1980, pesquisadores brasileiros determinaram excelente atividade desta molécula contra o Tripanosoma cruzi, em ratos, por via oral. Constam da literatura quatro rotas para a obtenção deste fármaco, que podem ser otimizadas no tocante ao aumento da produtividade e minimização dos riscos. A nova rota, ora proposta, é uma alternativa para a síntese do megazol, realizada somente em três etapas de fácil execução, abrindo caminho para obtenção de seus análogos estruturais. / In 1968, Berkelhammer and Asato synthesized a compound of the 5-nitroimidazole group, called megazol. This compound demonstrated a high biological activity. In 1980, brazilian researchers tested the megazol in mices and they discovered an excellent activity of this against Chagas\' disease. There are four routes to synthesize these compound indicated in the literature. Actually, these routes can be optimized to achieve the yield and minimization of the risks involved in the unitary processo The new route proposed is an alternative to obtain the megazol in only three stages of easy perform. This method makes way to structural analogues of this drug.
57

Associação da 3-0-metilquercetina com beta-ciclodextrina : avaliação da complexação e penetração cutânea / 3-O-methylquercetin association with ß-cyclodextrin : evaluation of complexation and skin permeation

Schwingel, Liege Cassia January 2007 (has links)
No presente trabalho foi realizado o isolamento da 3-O-metilquercetina, a partir de produto seco do extrato de inflorescências de Achyrocline satureioides, e sua caracterização. Em etapa farmacotécnica, foi realizado o estudo da associação deste flavonóide com b-ciclodextrina, bem como testes preliminares de permeação cutânea das associações, incorporadas ou não em gel de hidroxipropilmetilcelulose. As técnicas espectroscópicas, infravermelho e ressonância magnética de hidrogênio, confirmaram a estrutura do flavonóide isolado. Para o doseamento da 3-Ometilquercetina, realizou-se a validação de metodologia analítica por cromatografia líquida de alta eficiência, obtendo-se linearidade, na faixa de concentração de 0,05 a 1,5 μg/mL, precisão e exatidão adequadas. A análise da associação da 3-Ometilquercetina com b-ciclodextrina por infravermelho, ressonância magnética de hidrogênio e a análise pelo método empírico de Mecânica Molecular (MM2) do software Chem3D Ultra (Versão 9.0, CambridgeSoft) indicam possível inclusão do anel B da 3-O-metilquercetina na cavidade da b-ciclodextrina, sendo a inserção do flavonóide pela borda das hidroxilas secundárias mais favorável do que pela borda das hidroxilas primárias. A b-ciclodextrina e o gel de hidroxipropilmetilcelulose promoveram a permeação do flavonóide através da pele. A realização de ensaios in vivo para a seleção da melhor formulação constitui-se na principal perspectiva de continuidade de investigação científica do tema. / 3-O-methylquercetin (3-OMQ) was isolated from spray dried powder of Achyrocline satureioides and characterized by IR and 1H NMR. The study of association of this flavonoid with b-cyclodextrin (bCD) was performed, as well as preliminary skin permeation tests of these associations, incorporated or not in hydroxypropyl methylcellulose (HPMC) hydrogel. A LC method for 3-OMQ assay was validated in the concentration range from 0.05 to 1.5 μg/mL, with suitable precision and accuracy. The complexation of 3-OMQ with bCD was analyzed by IR, 1H NMR and Molecular Mechanics (Chem3D Ultra 9.0, CambridgeSoft) and the results indicated the possible insertion of B ring of the flavonoid into the bCD cavity, being the insertion through the secondary OH rim more favorable than through the primary OH rim. bCD and HPMC promoted the permeation of the flavonoid through the skin. In vivo assay is required to select the appropriate formulation.
58

Síntese e avaliações físico-químicas de quitosanas quimicamente modificadas pela inserção de radicais de anidrido succínico / Synthesis and physico-chemical evaluations of chitosan chemically modified by the insertion of succinic anhydride radicals

Mello, Karine Gargioni Pereira Correa de 01 September 2005 (has links)
A N-succinil-quitosana é um derivado quimicamente modificado do polímero quitosana. A inserção de radicais de anidrido succínico nas aminas protonadas presentes ao longo da cadeia do polímero quitosana, conferem diferentes características físico-químicas à molécula de quitosana. Esta modificação química possibilitou à quitosana, solubilidade em pHs que variam do ácido (2.0) até alcalino (14.0). Estas propriedades são atribuídas ao alongamento da cadeia alquílica, que afasta a ponte hidrofílica da cadeia fechada da D-glicosamina, facilitando o acesso da água, a qual irá estabelecer uma interação mais forte com a molécula de quitosana. Esta propriedade não está presente em amostras de quitosana pura, a qual sabe-se que solubiliza-se apenas em pHs abaixo de 5.5. / The N-succinil-chitosan is a chemically modified derivative of the biopolymer chitosan. The succinic anhydride attached to the free amino groups presented along the chitosan\'s polymer chain imparts to the molecule different physicochemical properties not exhibited before the modification. These chemical modifications enhance chitosan\'s solubility in slightly acid, neutral and alkaline media. These properties are related to the long alkyllic chains attached to hydrophilic parts. In this case the hydrophilic part of D-¬glucosamine promotes stronger interactions with the water molecules, and consequently, enhances the solubility of the chitosan polymer. It is worthy mentioning that non-modified free chitosan is soluble only in acidic medium (pH &#8804;5.5).
59

Associação da 3-0-metilquercetina com beta-ciclodextrina : avaliação da complexação e penetração cutânea / 3-O-methylquercetin association with ß-cyclodextrin : evaluation of complexation and skin permeation

Schwingel, Liege Cassia January 2007 (has links)
No presente trabalho foi realizado o isolamento da 3-O-metilquercetina, a partir de produto seco do extrato de inflorescências de Achyrocline satureioides, e sua caracterização. Em etapa farmacotécnica, foi realizado o estudo da associação deste flavonóide com b-ciclodextrina, bem como testes preliminares de permeação cutânea das associações, incorporadas ou não em gel de hidroxipropilmetilcelulose. As técnicas espectroscópicas, infravermelho e ressonância magnética de hidrogênio, confirmaram a estrutura do flavonóide isolado. Para o doseamento da 3-Ometilquercetina, realizou-se a validação de metodologia analítica por cromatografia líquida de alta eficiência, obtendo-se linearidade, na faixa de concentração de 0,05 a 1,5 μg/mL, precisão e exatidão adequadas. A análise da associação da 3-Ometilquercetina com b-ciclodextrina por infravermelho, ressonância magnética de hidrogênio e a análise pelo método empírico de Mecânica Molecular (MM2) do software Chem3D Ultra (Versão 9.0, CambridgeSoft) indicam possível inclusão do anel B da 3-O-metilquercetina na cavidade da b-ciclodextrina, sendo a inserção do flavonóide pela borda das hidroxilas secundárias mais favorável do que pela borda das hidroxilas primárias. A b-ciclodextrina e o gel de hidroxipropilmetilcelulose promoveram a permeação do flavonóide através da pele. A realização de ensaios in vivo para a seleção da melhor formulação constitui-se na principal perspectiva de continuidade de investigação científica do tema. / 3-O-methylquercetin (3-OMQ) was isolated from spray dried powder of Achyrocline satureioides and characterized by IR and 1H NMR. The study of association of this flavonoid with b-cyclodextrin (bCD) was performed, as well as preliminary skin permeation tests of these associations, incorporated or not in hydroxypropyl methylcellulose (HPMC) hydrogel. A LC method for 3-OMQ assay was validated in the concentration range from 0.05 to 1.5 μg/mL, with suitable precision and accuracy. The complexation of 3-OMQ with bCD was analyzed by IR, 1H NMR and Molecular Mechanics (Chem3D Ultra 9.0, CambridgeSoft) and the results indicated the possible insertion of B ring of the flavonoid into the bCD cavity, being the insertion through the secondary OH rim more favorable than through the primary OH rim. bCD and HPMC promoted the permeation of the flavonoid through the skin. In vivo assay is required to select the appropriate formulation.
60

Associação da 3-0-metilquercetina com beta-ciclodextrina : avaliação da complexação e penetração cutânea / 3-O-methylquercetin association with ß-cyclodextrin : evaluation of complexation and skin permeation

Schwingel, Liege Cassia January 2007 (has links)
No presente trabalho foi realizado o isolamento da 3-O-metilquercetina, a partir de produto seco do extrato de inflorescências de Achyrocline satureioides, e sua caracterização. Em etapa farmacotécnica, foi realizado o estudo da associação deste flavonóide com b-ciclodextrina, bem como testes preliminares de permeação cutânea das associações, incorporadas ou não em gel de hidroxipropilmetilcelulose. As técnicas espectroscópicas, infravermelho e ressonância magnética de hidrogênio, confirmaram a estrutura do flavonóide isolado. Para o doseamento da 3-Ometilquercetina, realizou-se a validação de metodologia analítica por cromatografia líquida de alta eficiência, obtendo-se linearidade, na faixa de concentração de 0,05 a 1,5 μg/mL, precisão e exatidão adequadas. A análise da associação da 3-Ometilquercetina com b-ciclodextrina por infravermelho, ressonância magnética de hidrogênio e a análise pelo método empírico de Mecânica Molecular (MM2) do software Chem3D Ultra (Versão 9.0, CambridgeSoft) indicam possível inclusão do anel B da 3-O-metilquercetina na cavidade da b-ciclodextrina, sendo a inserção do flavonóide pela borda das hidroxilas secundárias mais favorável do que pela borda das hidroxilas primárias. A b-ciclodextrina e o gel de hidroxipropilmetilcelulose promoveram a permeação do flavonóide através da pele. A realização de ensaios in vivo para a seleção da melhor formulação constitui-se na principal perspectiva de continuidade de investigação científica do tema. / 3-O-methylquercetin (3-OMQ) was isolated from spray dried powder of Achyrocline satureioides and characterized by IR and 1H NMR. The study of association of this flavonoid with b-cyclodextrin (bCD) was performed, as well as preliminary skin permeation tests of these associations, incorporated or not in hydroxypropyl methylcellulose (HPMC) hydrogel. A LC method for 3-OMQ assay was validated in the concentration range from 0.05 to 1.5 μg/mL, with suitable precision and accuracy. The complexation of 3-OMQ with bCD was analyzed by IR, 1H NMR and Molecular Mechanics (Chem3D Ultra 9.0, CambridgeSoft) and the results indicated the possible insertion of B ring of the flavonoid into the bCD cavity, being the insertion through the secondary OH rim more favorable than through the primary OH rim. bCD and HPMC promoted the permeation of the flavonoid through the skin. In vivo assay is required to select the appropriate formulation.

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