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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.
41

The effect of filler, active ingredient and Kollidon® VA64 sollubility on the release profile of the active ingredient from wet granulation tablet formulations

Claassen, Petrus Jacobus January 2012 (has links)
There are mainly two manufacturing processes used in the pharmaceutical industry, namely direct compression and granulation of which granulation can be subdivided into wet granulation and dry granulation. Wet granulation is a process still widely used in the pharmaceutical industry and provides better control of drug content uniformity and compactibility at low drug concentrations. Lactose monohydrate and microcrystalline cellulose (MCC) were used as fillers in this study. Both these fillers possess unacceptable powder flow properties and the use of wet granulation may improve this property. One of the advantages of lactose monohydrate over MCC is that it is partially water soluble. A fractional factorial design was used in this study. Twelve tablet formulations were formulated containing different combinations of active ingredients (furosemide or pyridoxine hydrochloride), fillers (lactose monohydrate or MCC) and a binder (Kollidon® VA64) in three different concentrations (0.75, 1.5 or 3.0% w/w). The binder was used to produce granules by means of wet granulation, using ethanol as granulating fluid. The granules were dried in an oven and screened through different sized sieves to produce the final granulated powder formulations ready for tableting. A disintegrant (Ac-di-sol®) and lubricant (magnesium stearate) were incorporated into the granulated powder formulations extra-granular (0.5% w/w) and were kept as a constant in this study throughout all the formulations. A Turbula® mixer was used to mix the granulated powder formulations for a constant 5 minutes. During the first phase of the study, tablets were compressed using 2 compression settings (22 and 24). These compression settings were used to determine what effect different external pressures would have on the different tablet properties. Tablet weight for all the formulations was kept constant at 250 mg, although the volume of the matrix differed for each tablet formulation. The physical properties of the tablets were evaluated with regard to weight variation, mechanical strength (crushing strength and friability) and disintegration. Tablet formulation 12 yielded unsatisfactory tablets, due to poor powder flow into the die. Tablet formulations that contained the highest binder concentration (3.0% w/w) and were compressed at the highest compression setting (24) (formulations 4 and 9), exhibited the highest mechanical strength. The disintegration results revealed that the tablet formulations containing MCC as filler disintegrated faster compared to those containing lactose monohydrate. The increase in binder concentration caused an increase in mechanical strength, possibly decreasing tablet porosity, therefore prolonging disintegration time due to impeded water penetration into the tablet matrix. During the final phase of the study, dissolution studies were conducted on the different tablet formulations in 0.1 M HCl for 120 minutes. In terms of dissolution results, the initial dissolution rate (DRi) and extent of dissolution (AUC) were compared. It was found that the tablet formulations containing pyridoxine hydrochloride as active pharmaceutical ingredient (API) exhibited faster drug dissolution (higher DRi and AUC-values) compared to those tablet formulations containing furosemide. The faster dissolution exhibited by the pyridoxine hydro- chloride containing formulations can possibly be attributed to the fact that pyridoxine hydrochloride is good water soluble whereas furosemide is practically insoluble in water. The effect of the filler depended on the aqueous solubility of the filler and the concentration of the binder (Kollidon VA64) employed. An increase in binder concentration led to a decrease in the initial rate of dissolution as well as the extent of drug dissolution. In the case of the pyridoxine hydrochloride containing formulations, formulation 9 exhibited the slowest DRi and lowest extent of drug dissolution (1.40 ± 0.03 µg.cm-3.min-1 and 2396.52 ± 26.43 µg.cm-3.min respectively). In the case of the furosemide containing formulations, formulation 4 exhibited the slowest DRi and lowest extent of drug dissolution (0.22 ± 0.07 µg.cm-3.min-1 and 1018.62 ± 59.74 µg.cm-3 min respectively). In both cases, the formulations contained Kollidon VA64 in a concentration of 3% w/w and were compressed at compression setting 24. The disintegration process of tablets goes hand in hand with the dissolution process and results have shown that by establishing rapid contact between drug particles and the surrounding medium proves to be a necessity for rapid drug dissolution. Disintegration does not assure drug dissolution, but when prolonged, slower dissolution rates can be obtained, implying a slow rate and low extent of drug dissolution. The disintegrant in this study was incorporated extra-granular ensuring rapid tablet disintegration. However, due to binder concentration of 3% w/w, granule disintegration was probably negatively affected resulting in a lower drug surface area exposed to the surrounding dissolution medium, leading to a slower initial rate and extent of drug dissolution. From the results obtained during this study it was evident that formulation variables such as the type of filler, the concentration of the binder and compression setting employed during tablet manufacturing can have a ronounced effect on the pharmaceutical availability of the active ingredient. However, the extent of the effect was dependent on the aqueous solubility of the active ingredient. / Thesis (MSc (Pharmaceutics))--North-West University, Potchefstroom Campus, 2013.
42

Influence of particle size on solubility of active pharmaceutical ingredients / E.C. Lubbe

Lubbe, Elizabeth Cornelia January 2012 (has links)
The aqueous solubility of an active pharmaceutical ingredient (API) is an important property that requires evaluation during early development and prior to formulation of the final product. With general, experimental, solubility testing of different APIs, the question always arises as to whether particle size had been determined beforehand or not. All available literature suggests that particle size, for pharmaceutical powders, does not significantly affect equilibrium solubility. The dissolution rate will differ according to different particle sizes, but the overall results should be identical after equilibrium is established. This study was therefore planned to investigate as to whether different particle size fractions of the same API, dissolving at different rates, would all reach solubility equilibrium within 24 hours. Also, APIs from different solubility classes were investigated, because poorly soluble substances would most likely require a longer period of time to equilibrate. The time period of 24 hours was selected, because many published solubility studies report using that interval and is it the standard for our research group also. Available APIs were selected to determine the influence (if any) of particle size on their equilibrium solubilities and the time required for attaining that status. For the purpose of this investigation, five APIs were selected from compounds at our disposal in-house, ranging from freely soluble to poorly soluble in the order: chloroquine phosphate > pyrazinamide > mefloquine hydrochloride > closantel sodium > roxithromycin. Solubility studies were successfully completed on four of the five APIs selected. For closantel sodium, pyrazinamide and roxithromycin it was demonstrated that the 24 hour test period was sufficient for the attainment of equilibrium solubility, regardless of the particle size fractions tested. Surprisingly, the only API in this study for which 24 hours was an insufficient test period was mefloquine HCl, which was not the least soluble compound tested. Further testing would be required to clarify this anomaly. What was evident from the outcomes of this investigation was that although the ubiquitous 24 hour solubility test may work well in many cases, its suitability should be reviewed on a case-by-case basis and not just for the most poorly soluble compounds. Researchers testing solubility at temperatures lower than 37°C should be especially cautious of using a standardised test period, because equilibrium solubility would take longer to achieve with less energy available to the system. / Thesis (MSc (Pharmaceutics))--North-West University, Potchefstroom Campus, 2013
43

The effect of filler, active ingredient and Kollidon® VA64 sollubility on the release profile of the active ingredient from wet granulation tablet formulations

Claassen, Petrus Jacobus January 2012 (has links)
There are mainly two manufacturing processes used in the pharmaceutical industry, namely direct compression and granulation of which granulation can be subdivided into wet granulation and dry granulation. Wet granulation is a process still widely used in the pharmaceutical industry and provides better control of drug content uniformity and compactibility at low drug concentrations. Lactose monohydrate and microcrystalline cellulose (MCC) were used as fillers in this study. Both these fillers possess unacceptable powder flow properties and the use of wet granulation may improve this property. One of the advantages of lactose monohydrate over MCC is that it is partially water soluble. A fractional factorial design was used in this study. Twelve tablet formulations were formulated containing different combinations of active ingredients (furosemide or pyridoxine hydrochloride), fillers (lactose monohydrate or MCC) and a binder (Kollidon® VA64) in three different concentrations (0.75, 1.5 or 3.0% w/w). The binder was used to produce granules by means of wet granulation, using ethanol as granulating fluid. The granules were dried in an oven and screened through different sized sieves to produce the final granulated powder formulations ready for tableting. A disintegrant (Ac-di-sol®) and lubricant (magnesium stearate) were incorporated into the granulated powder formulations extra-granular (0.5% w/w) and were kept as a constant in this study throughout all the formulations. A Turbula® mixer was used to mix the granulated powder formulations for a constant 5 minutes. During the first phase of the study, tablets were compressed using 2 compression settings (22 and 24). These compression settings were used to determine what effect different external pressures would have on the different tablet properties. Tablet weight for all the formulations was kept constant at 250 mg, although the volume of the matrix differed for each tablet formulation. The physical properties of the tablets were evaluated with regard to weight variation, mechanical strength (crushing strength and friability) and disintegration. Tablet formulation 12 yielded unsatisfactory tablets, due to poor powder flow into the die. Tablet formulations that contained the highest binder concentration (3.0% w/w) and were compressed at the highest compression setting (24) (formulations 4 and 9), exhibited the highest mechanical strength. The disintegration results revealed that the tablet formulations containing MCC as filler disintegrated faster compared to those containing lactose monohydrate. The increase in binder concentration caused an increase in mechanical strength, possibly decreasing tablet porosity, therefore prolonging disintegration time due to impeded water penetration into the tablet matrix. During the final phase of the study, dissolution studies were conducted on the different tablet formulations in 0.1 M HCl for 120 minutes. In terms of dissolution results, the initial dissolution rate (DRi) and extent of dissolution (AUC) were compared. It was found that the tablet formulations containing pyridoxine hydrochloride as active pharmaceutical ingredient (API) exhibited faster drug dissolution (higher DRi and AUC-values) compared to those tablet formulations containing furosemide. The faster dissolution exhibited by the pyridoxine hydro- chloride containing formulations can possibly be attributed to the fact that pyridoxine hydrochloride is good water soluble whereas furosemide is practically insoluble in water. The effect of the filler depended on the aqueous solubility of the filler and the concentration of the binder (Kollidon VA64) employed. An increase in binder concentration led to a decrease in the initial rate of dissolution as well as the extent of drug dissolution. In the case of the pyridoxine hydrochloride containing formulations, formulation 9 exhibited the slowest DRi and lowest extent of drug dissolution (1.40 ± 0.03 µg.cm-3.min-1 and 2396.52 ± 26.43 µg.cm-3.min respectively). In the case of the furosemide containing formulations, formulation 4 exhibited the slowest DRi and lowest extent of drug dissolution (0.22 ± 0.07 µg.cm-3.min-1 and 1018.62 ± 59.74 µg.cm-3 min respectively). In both cases, the formulations contained Kollidon VA64 in a concentration of 3% w/w and were compressed at compression setting 24. The disintegration process of tablets goes hand in hand with the dissolution process and results have shown that by establishing rapid contact between drug particles and the surrounding medium proves to be a necessity for rapid drug dissolution. Disintegration does not assure drug dissolution, but when prolonged, slower dissolution rates can be obtained, implying a slow rate and low extent of drug dissolution. The disintegrant in this study was incorporated extra-granular ensuring rapid tablet disintegration. However, due to binder concentration of 3% w/w, granule disintegration was probably negatively affected resulting in a lower drug surface area exposed to the surrounding dissolution medium, leading to a slower initial rate and extent of drug dissolution. From the results obtained during this study it was evident that formulation variables such as the type of filler, the concentration of the binder and compression setting employed during tablet manufacturing can have a ronounced effect on the pharmaceutical availability of the active ingredient. However, the extent of the effect was dependent on the aqueous solubility of the active ingredient. / Thesis (MSc (Pharmaceutics))--North-West University, Potchefstroom Campus, 2013.
44

Anger and anxiety in patients with primary aldosteronism treated with amiloride hydrochloride or spironolactone or adrenalectomy

Armstrong, Robin Sherill January 2007 (has links)
In Primary Aldosteronism (PAL) excessive amounts of aldosterone cause sodium and water retention and, in many individuals, this leads to moderate to severely high blood pressure. Although the chemistry and physiology are increasingly well understood, including the outcomes of treatment on physical health, there has been no systematic study of the psychological dimension of PAL. Anecdotally, patients exhibit symptoms such as angry outbursts, irritability, anxiety and defensiveness, and partners of these patients sometimes mention poor anger control and brittle or unpredictable moods. This thesis reports a systematic study of anger and anxiety among patients undergoing treatment for PAL. Eighty-three patients were recruited over an 11-month period to a prospective, pre-post design study to determine if treatment was associated with change in psychological state. Participants completed the State-Trait Anger Expression Inventory (STAXI-2), State-Trait Anxiety Inventory (STAI) and Psychosocial Adjustment to Illness Scale (PAIS) questionnaires. Adrenal Vein Sampling confirmed overproduction of aldosterone in one or both adrenal glands. Patients with Aldosterone Producing Adenoma (APA) were offered adrenalectomy. As per usual treatment protocols, patients with Bilateral Adrenal Hyperplasia (BAH) were prescribed spironolactone or amiloride depending predominantly on severity of blood pressure and potassium levels. Post-test questionnaires were completed after 6-8 months. Analysis was by mixed design (between-within subjects) ANOVA. Participant numbers in the adrenalectomy group fell far short of expectations. Fourteen past patients who had undergone unilateral adrenalectomy completed a retrospective semi-structured questionnaire. This qualitative data was analysed to identify themes similar to quantitative data. At baseline, 'non-completers' (ie those who did not complete the post-test; n=19), were significantly more angry than 'completers' (n=50) in State Anger (p< .01), Trait Anger (p< .05) and Anger Expression Index (p< .001). Trait Anxiety was also higher (p< .05), as was Psychological Distress (p< .05). Among those who participated at both interviews, there was small but statistically significant adverse treatment effect with higher scores for State Anger (p< .05), and Feeling Angry (p< .05). However for Trait Anger (p< .01), and 2 of its 3 sub-scales Angry Temperament (p< .05) and Angry Reaction (p< .01) there was a slight to moderate decrease in negative affect with treatment. Psychological Distress scores also improved (p< .05). Across all ANOVAs, there were no significant interaction effects, suggesting that any treatment effect was equivalent for the two drugs. Qualitatively collected data elucidated participants' changes in approach to life and relationships since adrenalectomy. Themes that emerged in the data included improved ability to cope with external stress, better control of emotions, more relaxed relationships and attitude to work, and a greater vitality and quality of life. Generally the comments were consistent with the drug treatments; there was noticeable benefit, including perceived better anger control and less anxiety. Positive psychological effects of treatment observed in the two drug groups were triangulated with data from a qualitative study. The combined evidence suggests that when excess circulating aldosterone is reduced (adrenalectomy), or blocked (spironolactone), or aldosterone's salt and water retaining effects are minimised (amiloride), then nervous irritability and its subsequent psycho-behavioural manifestations are reduced. The effect however is slight and the conclusions are weakened by an apparent attrition bias, and the absence of a control group. Implications for further research are discussed.
45

Avaliação da atividade antifúngica do Cloridrato de Verapamil frente a leveduras do gênero Candida / Evaluation of the antifungal activity of Verapamil Hydrochloride against yeasts of the genus Candida

Oliveira, Priscila dos Santos 06 August 2018 (has links)
Submitted by Priscila dos Santos Oliveira (priscilaspitty@hotmail.com) on 2018-08-29T22:43:22Z No. of bitstreams: 1 Merged_Priscila Oliveira.pdf: 1205779 bytes, checksum: 2ed8db0dfdefdc0a97d7a31fad8acaa9 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-09-03T14:47:25Z (GMT) No. of bitstreams: 1 Oliveira_mp_me_sjc.pdf: 1205779 bytes, checksum: 2ed8db0dfdefdc0a97d7a31fad8acaa9 (MD5) / Made available in DSpace on 2018-09-03T14:47:25Z (GMT). No. of bitstreams: 1 Oliveira_mp_me_sjc.pdf: 1205779 bytes, checksum: 2ed8db0dfdefdc0a97d7a31fad8acaa9 (MD5) Previous issue date: 2018-08-06 / Resumo: A epidemiologia das infecções causadas por Candida sofreu mudanças nos últimos anos. Embora Candida albicans ainda seja o principal patógeno causador de candidíase, relatos recentes reportam o aumento da incidência de infecções causadas por espécies de Candida não-albicans. A toxicidade dos fármacos antifúngicos utilizados juntamente com o desenvolvimento da resistência tem se tornado um sério problema clínico. Com isso, atualmente existe a urgência na descoberta de novos compostos com atividades antifúngicas. Objetivos: avaliar a atividade antifúngica do fármaco Cloridrato de Verapamil, determinar a Concentração Inibitória Mínima (CIM) e a Concentração Fungicida Mínima (CFM), frente à Candida albicans ATCC 18804, Candida krusei ATCC 6258, Candida parapsilosis ATCC 90018 e Candida glabrata ATCC 9030. Além de avaliar a citotoxicidade do fármaco em queratinócitos humanos (HaCaT). Metodologia: a determinação da CIM foi realizada pela técnica de microdiluição de acordo com The European Committee on Antimicrobial Susceptibility Testing (EUCAST). A CFM foi determinada por plaqueamento em ágar Sabouraud de alíquotas provenientes das diluições do ensaio de microdiluição. A avaliação da citotoxicidade foi realizada pela técnica de redução da resazurina, sendo possível avaliar a atividade mitocondrial das células HaCaT. Resultados: o fármaco Cloridrato de Verapamil demonstrou atividade antifúngica contra as quatro espécies patogênicas de Candida, com o valor de CIM de 1250 µM; valor de CFM maior que 1250 µM, sendo assim este fármaco foi considerado fungistático. Além disso, o Cloridrato de Verapamil não apresentou citotoxicidade nas concentrações avaliadas no estudo, pois, a redução de células viáveis nas concentrações mais elevadas não ultrapassa 30%. Com relação à redução de biomassa em biofilme de Candida, após tratamento com Cloridrato de Verapamil, houve redução (de 10 a 20%) para as quatro espécies de Candida em estudo, quando utilizadas concentrações de fármaco correspondentes a CIM; quando utilizadas concentrações de fármaco correspondentes a cinco vezes o valor de CIM, houve um aumento significativo na redução de biomassa (de 25% a 60%) em biofilme formado pelas quatro espécies de Candida. Conclusão: o fármaco Cloridrato de Verapamil apresentou atividade antifúngica para Candida albicans e Candida não-albicans, sendo considerado um fármaco fungistático, além de não apresentar citotoxicidade em queratinócitos humanos, e demonstrar atividade na redução de biomassa em biofilme formado pelas quatro espécies de Candida. Demais estudos são necessários para verificar a ação desse fármaco em diferentes mecanismos de virulência frente a células de Candida spp. / Abstract: The epidemiology of Candida infections has changed in recent years. Although Candida albicans is still the main pathogen causing candidiasis, recent reports have reported an increase in the incidence of infections caused by nonalbicans Candida species. The toxicity of the antifungal drugs used together with the development of resistance has become a serious clinical problem. With this, there is now an urgency in the discovery of new compounds with antifungal activities. Objectives: To evaluate the antifungal activity of the drug Verapamil Hydrochloride, to determine the Minimum Inhibitory Concentration (MIC) and the Minimum Fungicidal Concentration (CFM) against Candida albicans ATCC 18804, Candida krusei ATCC 6258, Candida parapsilosis ATCC 90018 and Candida glabrata ATCC 9030 In addition to evaluating the cytotoxicity of the drug in human keratinocytes (HaCaT). Methodology: MIC determination was performed by the microdilution technique according to The European Committee on Antimicrobial Susceptibility Testing (EUCAST). The CFM was determined by plating on Sabouraud agar from aliquots from the dilutions of the microdilution assay. The evaluation of cytotoxicity was performed using the resazurin reduction technique, and it was possible to evaluate the mitochondrial activity of HaCaT cells. Results: The drug Verapamil Hydrochloride demonstrated antifungal activity against the four pathogenic species of Candida, with MIC value of 1250 μM; CFM value greater than 1250 μM, so this drug was considered fungistatic. In addition, Verapamil Hydrochloride did not present cytotoxicity in the units evaluated in the study, because the reduction of viable cells in the most cells is not exceeded by 30%. Regarding the biomass reduction in Candida biofilm, after treatment with Verapamil Hydrochloride, there was a reduction (from 10 to 20%) for the four Candida species in study, when the use of drug corresponding to MIC; when the use of drug corresponding to 5 times of MIC, there was a significant increase in the biomass reduction (from 25% to 60%) in the biofilm molded by the four Candida species. Conclusion: Thus, the drug Verapamil Hydrochloride led to the antifungal activity of Candida albicans and non-albicans Candida species, being considered a fungicidal drug, besides not presenting cytotoxicity in human serotonizers, and were submitted to biomass reduction in biofilm molded by four Candida species. More studies are needed to verify the action of the drug on different mechanisms of virulence against Candida spp cells.
46

Determinação de pressão de sublimação de cloridratos de amina através da técnica termogravimétrica

Belusso, Anne Caroline January 2017 (has links)
A presença de sais no petróleo ocasiona grandes problemas operacionais relacionados à corrosão, uma vez que estes acabam formando ácido clorídrico no processo de separação do óleo bruto. Com o intuito de amenizar os efeitos de corrosão ácida, aminas podem ser adicionadas no topo das colunas para agir como neutralizantes. Porém, dependendo das condições operacionais e da quantidade de amina adicionada, pode ocorrer a deposição de cloridratos de aminas, promovendo a corrosão sob depósito. Assim, o conhecimento da pressão de sublimação desses sólidos é de extrema importância para especificar as condições de operação e o melhor desempenho destes aditivos no processo. Dentro desse contexto, o objetivo deste trabalho é determinar as pressões e entalpias de sublimação de cloridratos de aminas com a técnica termogravimétrica. Devido às dificuldades encontradas para obtenção de dados precisos de pressão em baixas temperaturas, uma extensão ao método termogravimétrico foi proposta, tornando possível medir pressões na ordem de 1 0,5 Pa. As substâncias estudadas foram: brometo de amônio, cloreto de amônio, cloridrato de etanolamina, cloridrato de metilamina, cloridrato de piridina, cloridrato de trimetilamina e dicloridrato de n-(1- naftil)etilenodiamina. Resultados de pressão e entalpia de sublimação alcançados com ácido benzoico, brometo de amônio e cloreto de amônio foram validados com dados da literatura Para os demais sólidos estudados, não há muitos dados disponíveis na literatura. No entanto, como a reação de sublimação do cloreto de amônio é análoga à dos demais cloridratos de amina, as entalpias de sublimação puderam ser comparadas e os resultados encontrados foram satisfatórios. Por fim, para uma melhor aplicabilidade dos resultados obtidos, uma equação de Clausius-Clapeyron modificada foi utilizada para correlacionar os dados medidos. Uma ótima correlação foi possível para todos os sais estudados, com coeficiente de correlação sempre superior a 0,97. / The presence of salts in petroleum causes operational problems related to corrosion, due to the fact that they end up forming hydrochloric acid in the crude oil separation process. In order to mitigate the effects of acid corrosion, amines can be added at the top of the columns to act as neutralizers. However, depending on the operational conditions and the amount of amine added, a deposition of amine hydrochlorides may occur, promoting under-deposit corrosion. Thus, the knowledge of the sublimation pressure of these salts has an extreme importance in trying to predict and to optimize the performance of the additives in the process. Within this context, the purpose of this study is to determine pressure and enthalpy of sublimation of amine hydrochlorides with the thermogravimetric technique. Due to the difficulties encountered to obtain precise pressure data at low temperatures, an extension of the thermogravimetric method was proposed, enabling to measure sublimation pressures in the order of 1 0,5 Pa. The substances studied were: ammonium bromide, ammonium chloride, ethanolamine hydrochloride, methylamine hydrochloride, pyridine hydrochloride, trimethylamine hydrochloride and n-(1-naphthyl)ethylenediamine dihydrochloride. Results of pressure and enthalpy of sublimation obtained with benzoic acid, ammonium bromide and ammonium chloride were validated using literature data. For other solids investigated in this study, experimental data is scarce in the literature. However, as the sublimation reaction of ammonium chloride is analogous to the others amine hydrochlorides, enthalpies of sublimation could be compared with the results found. Since similar values were observed, the results were considered satisfactory. Finally, the measured data were correlated using a modified Clausius-Clapeyron equation. A good correlation was possible for all salts studied, with correlation coefficient always higher than 0.97.
47

Análise químico-farmacêutica de cloridrato de ciprofloxacino em solução oftálmica

Cazedey, Edith Cristina Laignier [UNESP] 02 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-02Bitstream added on 2014-06-13T20:33:02Z : No. of bitstreams: 1 cazedey_ecl_me_arafcf.pdf: 802368 bytes, checksum: 7af4d6526e6d1c491bb231f706185aea (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O cloridrato de ciprofloxacino, um antibacteriano quinolônico, apresenta amplo espectro de ação e é eficaz in vitro contra praticamente todos os patógenos Gram-negativos, incluindo Pseudomonas aeruginosa. Mostra-se também eficaz contra microrganismos Gram-positivos, como estafilococos e estreptococos. A importância de desenvolver e validar métodos analíticos para este fármaco é justificada por seu potencial terapêutico, grande emprego em terapias microbianas e baixo custo, assim como pelo conhecimento de que a baixa qualidade dos produtos anti-infecciosos está relacionada ao desenvolvimento de cepas resistentes, como consequência da administração de doses subterapêuticas. Por tal razão, é de enorme importância o desenvolvimento de métodos analíticos eficazes e confiáveis para o controle de qualidade dos medicamentos comercializados. Neste trabalho foram desenvolvidos métodos de análise para o cloridrato de ciprofloxacino em solução oftálmica. Os métodos desenvolvidos e validados foram: (i) doseamento microbiológico, método turbidimétrico na faixa de concentração de 14,0 a 56,0 μg/mL, utilizando Staphylococcus epidermidis ATCC 12228 IAL 2150, com exatidão de 99,71% e teor de 102,27%; (ii) método espectrofotométrico na região do UV a 275 nm com faixa de concentração de 2,0 a 7,0 μg/mL, utilizando água como solvente, com exatidão de 101,51% e teor de 99,79%; (iii) método espectrofotométrico derivativo na região do visível a 386,4 nm, na primeira derivada, com faixa de concentração de 50,0 a 100,0 μg/mL, utilizando cloreto férrico 1,0% como reagente, com exatidão de 99,83% e teor de 106,72%; (iv) método por cromatografia líquida de alta eficiência com detector UV a 275 nm, com fase móvel composta por ácido acético 2,5% v/v, metanol e acetonitrila (70:15:15, v/v/v) e faixa de concentração de 1,0 a 6,0 μg/mL, exatidão... / Ciprofloxacin hydrochloride, a quinolone antibiotic, presents a wider spectrum of activity and is effective against practically all Gram-negative pathogens, including Pseudomonas aeruginosa. It is potent against Grampositive microorganisms, as Staphylococcus and Streptococcus. Analytical methods for quantitative determination of ciprofloxacin hydrochloride is important due to its therapeutic potential, wide use in antimicrobial therapy and low cost. Moreover, it is known that the poor quality antibiotic product is direct related development of resistant strains, as consequence of subtherapeutic doses administration. Thus, it is important to develop efficient analytical methods for quality control commercialized products. In this work, analytical methods for determination of ciprofloxacin hydrochloride were validated: (i) microbiological assay, turbidimetric method at concentration range 14.0 to 56.0 μg/mL, using Staphylococcus epidermidis ATCC 12228 IAL 2150 as indicator microorganism, accuracy 99.71% and quantitation of 102.27; (ii) UV spectrophotometry at 275 nm with concentration range of 2.0 to 7.0 μg/mL, using water as solvent, with accuracy of 101.51% and quantitation of 99.79%; (iii) Derivative visible spectrophotometric method at 386.4 nm, in first derivate, with concentration range of 50.0 a 100.0 μg/mL, using 1.0% ferric chloride as reagent, with accuracy of 99.83% and quantitation of 106.72%; (iv) HPLC method with UV detector at 275 nm using 2.5 M acetic acid (v/v), methanol and acetonitrile (70: 15: 15, v/v/v) as mobile phase and concentration range of 1.0 to 6.0 μg/mL, accuracy of 100.11%, quantitation 103.25% and mean retention time of 2.6 minutes; (v) Indirect titrimetric method using bromate/bromide solution in acid medium as reagent in concentration range of 1.0 to 11.0 mg/mL, with accuracy of 100.28% and quantitation of 98.97%.
48

Desenvolvimento e estudo de materiais híbridos siloxano-poli(óxipropileno) para liberação prolongada do cloridrato de propranolol / Study and development of siloxane-Poly(propylene oxide) hybrid materials for prolonged drug delivery of propranolol hydrochloride

Silva, Ranielle de Oliveira [UNESP] 09 May 2016 (has links)
Submitted by RANIELLE DE OLIVEIRA SILVA null (ranielleborges@yahoo.com.br) on 2016-06-14T16:20:17Z No. of bitstreams: 1 DissertaçãoMestrado_Ranielle_Silva 2.pdf: 11995453 bytes, checksum: abf2ac6021bf67009b8af99fe28a0026 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-06-16T14:40:09Z (GMT) No. of bitstreams: 1 silva_ro_me_araiq_par.pdf: 1314893 bytes, checksum: 9254863d01a93bf48fa2f06ae37a9209 (MD5) / Made available in DSpace on 2016-06-16T14:40:09Z (GMT). No. of bitstreams: 1 silva_ro_me_araiq_par.pdf: 1314893 bytes, checksum: 9254863d01a93bf48fa2f06ae37a9209 (MD5) Previous issue date: 2016-05-09 / Híbridos Siloxano-PPO obtidos pela síntese sol-gel foram utilizados como matrizes carreadoras do fármaco cloridrato de propranolol com interesse de se aumentar a disponibilidade do fármaco em meio aquoso. Foram preparados amostras contendo teores de 5 e 30% do fármaco. A eficiência na formação da rede híbrida foi confirmada por análises FTIR, RMN e SAXS. A cinética de liberação mostrou que ela ocorre de forma prolongada (superior a 1200 h) com regimes intermitentes de aceleração e desaceleração da taxa de liberação. Foram aplicados ajustes matemáticos a cada regime utilizando a equação de Korsmayer-Peppas que demonstraram que a saída do fármaco ocorre por diferentes mecanismos. Observou-se que o acesso da água na amostra durante a liberação não é homogêneo, mas sim gradual da superfície ao centro. Devido a esses fenômenos as caracterizações foram feitas em diferentes regiões da amostra (periferia e centro) e em diferentes períodos da liberação, visando acompanhar a difusão da água para o interior da amostra e a cinética de saída do fármaco. As análises estruturais de DRX e as térmicas por TGA e DSC mostraram que o fármaco é incorporado na matriz híbrida na forma solubilizada e na forma cristalina. As medias realizadas em função do tempo mostraram que a velocidade de saída do fármaco e de entrada da água na matriz híbrida é maior na superfície em relação ao volume, confirmando o acesso gradual da água. Essas análises indicam a correlação entre as fases cristalina do fármaco com os primeiros regimes e da parte solubilizada com a liberação mais lenta. As medidas de DSC mostraram que o acesso da água em regiões mais internas da amostra resultaram no comportamento de confinamento da água, indicado pelo fenômeno de super congelamento. Foi detectado por medias de SAXS a existência de espalhadores secundários presentes em todas as amostras, inclusive nas matrizes híbridas sem a adição de fármaco, que foram atribuídos a agregados formados por domínios com maior densidade de nanopartículas de sílica. A evolução no tamanho desses agregados foi correlacionada aos regimes de liberação. Conclui-se, que a cinética de liberação tem uma forte dependência da evolução da matriz híbrida causadas por mudanças estruturais favorecidas pela mobilidade da cadeia polimérica e pela interação do fármaco com a água. / Siloxane-PPO hybrids obtained by sol-gel synthesis have been used as drug delivery systems for propranolol hydrochloride with the intent to increase the drug availability in the aqueous medium. Samples with 5% and 30% of drug have been prepared. The efficiency related to the formation of the hybrid network has been confirmed by means of FTIR, RMN and SAXS analyses. The drug delivery kinetics showed that it occurs in a prolonged form (more that 1200h) with increasing and decreasing intermediate release rates. The Korsmayer-Peppas equation has been used for each release rate with mathematical adjustments that displayed how the drug release occurred through different mechanisms. It has been observed that the water intake inside the sample during the drug release was not homogeneous but gradual, from the surface to the centre. Due to these phenomena, the characterizations have been carried out in different regions of the samples (exterior and interior) and at different drug delivery periods, aiming at accompanying the water diffusion to the sample centre and the drug release kinetics. The XRD structural analyses and the thermal analyses by means of TGA and DSC showed that the drug is incorporated in the hybrid matrix in a solubilized form and in a crystalline form. The tests done as function of time displayed that the drug release velocity and water intake inside the hybrid matrix is greater at the surface in relation to its volume, confirming the gradual access of water. These analyses point to the correlation between the drug crystalline phase with the first release regimes and between the solubilized form with the slower release. The DSC tests showed that the water intake inside more internal regions of the sample resulted in the water confinement, demonstrated by the super-cooling phenomenon. By means of SAXS, the existence in all the samples, including those without drug, of secondary scatterings has been observed and these have been attributed to aggregates formed by domains with a higher silica nanoparticle density. The size evolution of these aggregates has been correlated to the drug release regimes. It has been concluded that the drug release kinetics has a strong dependence with the hybrid matrix evolution caused by structural changes facilitated by polymer chain mobility and by drug/water interaction.
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Influência do treinamento de força associado ou não ao raloxifeno sobre o perfil transcricional e microestrutural ósseo de ratas Wistar naturalmente envelhecidas / Effects of strength trainingandraloxifeneon femoral neck metabolism and microarchitectureof aging female Wistar rats

Stringhetta-Garcia, Camila Tami [UNESP] 04 May 2017 (has links)
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Agradecemos a compreensão. on 2017-06-21T17:35:29Z (GMT) / Submitted by CAMILA TAMI STRINGHETTA GARCIA null (camilatami@foa.unesp.br) on 2017-06-21T17:47:05Z No. of bitstreams: 2 tese repositório.pdf: 1861224 bytes, checksum: e17a22f7d33f2afe16fcac0d6dca069c (MD5) Doutorado Camila Tami Stringhetta Garcia Ciências Fisiológicas.docx: 15609 bytes, checksum: 1a9fbbec0628b5693a09bbde2e6ed1d2 (MD5) / Rejected by Luiz Galeffi (luizgaleffi@gmail.com), reason: Solicitamos que realize uma nova submissão seguindo a orientação abaixo: A ficha catalográfica deve ser inserida na página subsequente à folha de rosto, de acordo com as normas de sua unidade. Corrija esta informação e realize uma nova submissão com o arquivo correto. Agradecemos a compreensão. on 2017-06-21T17:51:49Z (GMT) / Submitted by CAMILA TAMI STRINGHETTA GARCIA null (camilatami@foa.unesp.br) on 2017-06-21T18:26:14Z No. of bitstreams: 1 Tese repositório.pdf: 1864307 bytes, checksum: 332fcd04d3149c9d08b518d67f80556d (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-06-21T18:38:07Z (GMT) No. of bitstreams: 1 stringhettagarcia_ct_dr_araca.pdf: 1864307 bytes, checksum: 332fcd04d3149c9d08b518d67f80556d (MD5) / Made available in DSpace on 2017-06-21T18:38:07Z (GMT). No. of bitstreams: 1 stringhettagarcia_ct_dr_araca.pdf: 1864307 bytes, checksum: 332fcd04d3149c9d08b518d67f80556d (MD5) Previous issue date: 2017-05-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A ocorrência de doenças crônicas e degenerativas é significativamente maior nos organismos durante o envelhecimento, dentre elas, a osteoporose, que resulta em aumento no número de fraturas. As fraturas são as consequências mais dramáticas da osteoporose, sendo que do colo do fêmur é a mais severa, com maior incidência de morbidades e mortalidade. A menor concentração plasmática de estrogênio nas mulheres menopausadas, exerce ação primordial no desenvolvimento desta doença. Desta maneira, o objetivo deste estudo foi estudar a prevenção da osteoporose em decorrência do envelhecimento reprodutivo feminino, especificamente no período de periestropausa, utilizando treinamento de força (TF), raloxifeno (Ral) ou combinação de TF e Ral. Durante 120 dias, ratas Wistar no período do envelhecimento (18 a 21 meses) realizaram TF em escada três vezes por semana, receberam Ral (1mg/Kg/dia) por gavagem, ou realizaram TF associado ao tratamento com Ral. Microarquitetura óssea cortical e trabecular, densidade mineral óssea areal (DMOa), força óssea, imunoistoquímica (OCN, TRAP e SOST) e superfície de osteoclastos do colo do fêmur foram avaliadas, além de PCR (Runx2, Sp7, Alp, Bsp, Ocn, Rank, Rankl, Opg, Trap e Ctsk) e Western Blot (p-ERα e TRAP) do tecido ósseo de todo o fêmur. Os resultados demonstram que os tratamentos modularam o ciclo de remodelamento ósseo de maneiras diferentes: TF estimulou RNAm de marcadores osteoblásticos e osteoclásticos, enquanto Ral diminuiu marcadores osteoclásticos e TF associado a Ral aumentou marcadores osteoblásticos e diminuiu osteoclásticos. Ambos tratamentos resultaram em melhora da microarquitetura trabecular do colo do fêmur de ratas na periestropausa, todavia, apenas o TF foi capaz de melhorar além da microarquitetura trabecular, a cortical e força óssea. Desta maneira, sugerimos que a realização de TF, utilização de Ral ou a associação de TF e Ral durante a periestropausa são intervenções válidas na prevenção de osteoporose em decorrência do envelhecimento reprodutivo feminino, porém os efeitos do TF parecem ser superiores. Levando em consideração que a carga mecânica gerada pelo TF age também em tecidos não esqueléticos, concluímos que TF pode ser intervenção sistêmica para osteoporose. Esses resultados adicionam novas informações à literatura sobre terapêuticas preventivas para osteoporose e fornecem informações relevantes para estudos pré-clínicos. / The association of aging with osteoporosis results in an increased number of fractures. In these fractures, the femoral neck is involved in 75% of affected women and is one of the most dramatic possible consequences. The aim of this study was to prevent female osteoporosis using strength training (ST), raloxifene (Ral) or a combination of ST plus Ral during the natural female aging process, specifically in the periestropause period. For 120 total days, aging female Wistar rats at 18-21 months of age performed ST on three times per week, and Ral was administered daily by gavage (1mg/kg/day). Bone microarchitecture, areal bone mineral density (aBMD), bone strength of the femoral neck, immunohistochemistry, western blotting (p-ERα and TRAP) and RT-PCR were assessed. We found that the treatments modulate the bone remodeling cycle in different ways. Both ST and Ral treatment resulted in improved bone microarchitecture in the femoral neck of rats in late periestropause. However, only ST improved cortical microarchitecture and bone strength in the femoral neck. In addition, ST stimulated mRNA levels of osteoclastic and osteoblastic markers, while Ral decreased mRNA levels of osteoclastic markers. The combined ST plus Ral therapy increased osteoblastic markers and decreased osteoclast markers. In this way, we suggest that SF, the use of Ral or the association of ST and Ral during periestropause are valid interventions in the prevention of osteoporosis due to female reproductive aging, but the effects of ST seem to be superior, taking into account that the mechanical load generated by ST also acts on nonskeletal tissues, we conclude that ST can be a systemic intervention for osteoporosis. These results add new information to the literature on preventive therapies for osteoporosis and provide relevant information for preclinical studies.
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Análise químico-farmacêutica de cloridrato de ciprofloxacino em solução oftálmica /

Cazedey, Edith Cristina Laignier. January 2009 (has links)
Orientador: Hérida Regina Nunes Salgado / Banca: Magali Benjamin de Araújo / Banca: Hérida Regina Nunes Salgado / Banca: Greici Cristina Gomes Tozo / Resumo: O cloridrato de ciprofloxacino, um antibacteriano quinolônico, apresenta amplo espectro de ação e é eficaz in vitro contra praticamente todos os patógenos Gram-negativos, incluindo Pseudomonas aeruginosa. Mostra-se também eficaz contra microrganismos Gram-positivos, como estafilococos e estreptococos. A importância de desenvolver e validar métodos analíticos para este fármaco é justificada por seu potencial terapêutico, grande emprego em terapias microbianas e baixo custo, assim como pelo conhecimento de que a baixa qualidade dos produtos anti-infecciosos está relacionada ao desenvolvimento de cepas resistentes, como consequência da administração de doses subterapêuticas. Por tal razão, é de enorme importância o desenvolvimento de métodos analíticos eficazes e confiáveis para o controle de qualidade dos medicamentos comercializados. Neste trabalho foram desenvolvidos métodos de análise para o cloridrato de ciprofloxacino em solução oftálmica. Os métodos desenvolvidos e validados foram: (i) doseamento microbiológico, método turbidimétrico na faixa de concentração de 14,0 a 56,0 μg/mL, utilizando Staphylococcus epidermidis ATCC 12228 IAL 2150, com exatidão de 99,71% e teor de 102,27%; (ii) método espectrofotométrico na região do UV a 275 nm com faixa de concentração de 2,0 a 7,0 μg/mL, utilizando água como solvente, com exatidão de 101,51% e teor de 99,79%; (iii) método espectrofotométrico derivativo na região do visível a 386,4 nm, na primeira derivada, com faixa de concentração de 50,0 a 100,0 μg/mL, utilizando cloreto férrico 1,0% como reagente, com exatidão de 99,83% e teor de 106,72%; (iv) método por cromatografia líquida de alta eficiência com detector UV a 275 nm, com fase móvel composta por ácido acético 2,5% v/v, metanol e acetonitrila (70:15:15, v/v/v) e faixa de concentração de 1,0 a 6,0 μg/mL, exatidão... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Ciprofloxacin hydrochloride, a quinolone antibiotic, presents a wider spectrum of activity and is effective against practically all Gram-negative pathogens, including Pseudomonas aeruginosa. It is potent against Grampositive microorganisms, as Staphylococcus and Streptococcus. Analytical methods for quantitative determination of ciprofloxacin hydrochloride is important due to its therapeutic potential, wide use in antimicrobial therapy and low cost. Moreover, it is known that the poor quality antibiotic product is direct related development of resistant strains, as consequence of subtherapeutic doses administration. Thus, it is important to develop efficient analytical methods for quality control commercialized products. In this work, analytical methods for determination of ciprofloxacin hydrochloride were validated: (i) microbiological assay, turbidimetric method at concentration range 14.0 to 56.0 μg/mL, using Staphylococcus epidermidis ATCC 12228 IAL 2150 as indicator microorganism, accuracy 99.71% and quantitation of 102.27; (ii) UV spectrophotometry at 275 nm with concentration range of 2.0 to 7.0 μg/mL, using water as solvent, with accuracy of 101.51% and quantitation of 99.79%; (iii) Derivative visible spectrophotometric method at 386.4 nm, in first derivate, with concentration range of 50.0 a 100.0 μg/mL, using 1.0% ferric chloride as reagent, with accuracy of 99.83% and quantitation of 106.72%; (iv) HPLC method with UV detector at 275 nm using 2.5 M acetic acid (v/v), methanol and acetonitrile (70: 15: 15, v/v/v) as mobile phase and concentration range of 1.0 to 6.0 μg/mL, accuracy of 100.11%, quantitation 103.25% and mean retention time of 2.6 minutes; (v) Indirect titrimetric method using bromate/bromide solution in acid medium as reagent in concentration range of 1.0 to 11.0 mg/mL, with accuracy of 100.28% and quantitation of 98.97%. / Mestre

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