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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.
31

Towards a mechanistic understanding of pharmaceutical protein stabilization in solution and the solid state /

Katayama, Derrick S. January 2006 (has links)
Thesis (Ph.D. in Pharmaceutical Sciences) -- University of Colorado at Denver and Health Sciences Center, 2006. / Typescript. Includes bibliographical references (leaves 159-173). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
32

Preparation of two-strain lyophilized lactic starters

Snudden, Birdell Harry, January 1964 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1964. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 75-81).
33

Desenvolvimento de forma farmacêutica sólida associação em dose fixa à base do extrato liofilizado de baccharis trimera (less.) Dc. E do sulfato de hidroxicloroquina como alternativa terapêutica para o tratamento da artrite reumatoide

SANTOS, Fabiana Lícia Araujo Dos 25 May 2015 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-04-10T19:15:40Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Fabiana Licia Araujo dos Santos.pdf: 3305306 bytes, checksum: e915bed6750342cef5b377cd2e10834e (MD5) / Made available in DSpace on 2017-04-10T19:15:41Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Fabiana Licia Araujo dos Santos.pdf: 3305306 bytes, checksum: e915bed6750342cef5b377cd2e10834e (MD5) Previous issue date: 2015-05-25 / CNPQ / Associação em Dose Fixa (ADF) é uma combinação de dois ou mais princípios ativos em uma razão fixa de doses em uma mesma forma farmacêutica. Comodidade para o paciente e consequente incremento na adesão ao tratamento são razões aventadas para estimular desenvolvimento de ADF, sendo estas particularmente importantes no tratamento de doenças crônicas. Assim, por associar atividade antiinflamatória, imunomoduladora e antiartritica, Baccharis trimera (Less.) DC. é uma planta promissora para compor uma ADF com o sulfato de hidroxicloroquina (HCQ), como alternativa inovadora para o tratamento da artrite reumatoide. O sulfato de HCQ integra a relação de fármacos recomendados no consenso brasileiro de doenças reumáticas, podendo inclusive ser utilizado durante o período de amamentação. Sendo assim, o objetivo desse estudo é a obtenção de uma forma farmacêutica ADF (cápsulas), utilizando como agentes terapêuticos o extrato seco liofolizado de B. trimera e o fármaco sulfato de HCQ. O extrato foi obtido por infusão e seco por processo de liofilização, apresentando rendimento de 9% (p/p). A técnica de cromatografia líquida de alta eficiência (CLAE) foi utilizada no ensaio de doseamento da droga vegetal e do extrato seco. As amostras apresentaram valores de 9 e 0,2 mg.g-1 de ácidos cafeicos, respectivamente. A técnica de termogravimetria (TG) revelou a eficiência do processo de liofilização, uma vez que não foi observado na curva TG do extrato seco o evento de perda de água na faixa de 27-100ºC, presente no perfil da droga vegetal. Em relação às propriedades de fluxo e tamanho de partícula, o extrato liofilizado apresentou-se como um pó fino, de elevada área superficial e presença de mesoporos, com baixa capacidade de fluxo, demonstrando a necessidade da adição de excipientes que possibilitem a utilização do insumo para a obtenção da forma farmacêutica. Na sequência, o sulfato de HCQ foi caracterizado por diversas técnicas, com destaque para a polarimetria, Microscopia Eletrônica de Varredura (MEV) e Difração de raios-X (DRX), comprovando a proporção equimolar dos isômeros da HCQ na mistura racêmica e a existência de cristais de tamanhos irregulares com formatos predominantemente hexagonais. A partir de um estudo de planejamento fatorial, otimizou-se o método analítico para doseamento do sulfato de HCQ por CLAE, com base na metodologia descrita na Farmacopeia Americana. O novo método provou ser mais rápido e mais eficiente em relação ao método de referência, por promover redução no tempo de retenção e redução no fluxo da fase móvel. Além disso, o método permitiu a quantificação do sulfato de HCQ a partir de um pico de alta resolução, apresentando valor de 1,087 para o fator de cauda, assegurando uma quantificação precisa da matéria-prima enquanto mistura racêmica. Através da obtenção de cinéticas de degradação dinâmica e isotérmica, o sulfato de HCQ revelou um prazo de validade estimado de 622 dias. A compatibilidade do fármaco-excipiente foi avaliada através de calorimetria exploratória diferencial (DSC), seguida de análises complementares, evidenciando incompatibilidade do fármaco com o glicolato de amido sódico e com a lactose. Diante de todos os dados obtidos durante os estudos de pré-formulação, foi possível desenvolver uma forma farmacêutica ADF que apresentou boas propriedades de fluxo e baixo teor de umidade, situação ideal para manter a estabilidade de formulações que contém extrato de origem vegetal. Esse produto inovador pode surgir como um alívio ao desconforto do paciente que muitas vezes utiliza diferentes classes de medicamentos para o controle de doenças crônicas, como a artrite reumatoide. / Fixed-dose combination (FDC) is an association of two or more active ingredients in a fixed ratio of doses in the same pharmaceutical form. Convenience for the patient and consequent increase in treatment adherence are reasons to stimulate development of FDC, which are particularly important in the treatment of chronic diseases. Thus, by associating anti-inflammatory, immunomodulatory and anti-arthritic activity, Baccharis trimera (Less.) DC is a promising plant to compose a FDC with hydroxychloroquine (HCQ ) sulfate, as an innovative alternative for the treatment of rheumatoid arthritis. The HCQ sulfate integrates the list of drugs recommended in the Brazilian consensus of rheumatic diseases, and it can even be used during breastfeeding. Therefore, the aim of this study is to obtain a pharmaceutical form (capsules) of a FDC, using as therapeutic agents the dry extract of B. trimera and the drug HCQ sulfate. The extract was obtained by infusion and dried by lyophilization process, with yield of 9% (w / w). The high-performance liquid chromatography (HPLC) was used in the assay of the herbal drug and its dry extract. The samples exhibited values of 9 and 0.2 mg.g-1 of cafeic acids, respectively. The thermogravimetry (TG) showed the efficiency of the lyophilization process, since it was not observed in the TG curve of the dry extract a water loss event from 27 to 100°C that is present in the herbal drug profile. Whereas flow properties and particle size, the lyophilized extract was characterized as a fine powder with a high surface area and the presence of mesopores, with low flowability, demonstrating the need for the addition of excipients that enable its use as an active pharmaceutical ingredient to obtaining the pharmaceutical form. Further, the HCQ sulfate was characterized by several techniques, especially polarimetry, Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD), proving the equimolar ratio of the isomers of HCQ in the racemic mixture and the existence of irregular crystal sizes predominantly in hexagonal shapes. The analytical method for determination of HCQ sulfate by HPLC was also optimized using factorial design. The new method has proved to be faster and more efficient compared to the reference method described at United States Pharmacopeia, by promoting a reduction in the retention time and reducing the flow of mobile phase. Furthermore, the method allows the quantification of HCQ sulfate from a peak of high resolution, presenting value of 1.087 for the tailing factor, assuring a precise quantification of the raw material as the racemic mixture. By obtaining dynamic and isothermal kinetics of degradation, HCQ sulfate revealed an estimated shelf life of 622 days. The drug-excipient compatibility was evaluated by differential scanning calorimetry (DSC), followed by complementary tests, highlighting drug incompatibility with sodium starch glycolate and lactose. Considering all the data obtained during the pre-formulation studies, it was possible to develop a FDC pharmaceutical dosage form which showed good flow properties and low moisture content, ideal situation to maintain the stability of formulations containing herbal extract. This innovative product may come as a relief to the discomfort of the patient who often uses different classes of drugs for the control of chronic diseases such as rheumatoid arthritis.
34

Preparation of Porous Materials with Aligned Pores by Unidirectional Freezing and Freeze-Drying / 一方向凍結乾燥法による配向制御された多孔構造体の形成

Kim, Jin Woong 23 March 2010 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15334号 / 工博第3213号 / 新制||工||1484(附属図書館) / 27812 / 京都大学大学院工学研究科化学工学専攻 / (主査)教授 大嶋 正裕, 教授 田門 肇, 教授 宮原 稔 / 学位規則第4条第1項該当
35

The thiamine, riboflavin, and niacin content of chicken muscles as affected by freeze-drying /

Rowe, Dorothy Marie January 1961 (has links)
No description available.
36

Microwave freeze-drying of aqueous solutions

Dolan, James P. 05 December 2009 (has links)
The freeze-drying process has been plagued with problems, such as long drying times and inefficiency. Microwave freeze-drying has proven its potential as way of reducing long drying times associated with freeze-drying, and as a result, there has been a considerable amount of work done to increase its use in industrial applications. However, it is not widely utilized for drying of pharmaceuticals, which appear to be better suited to microwave freeze-drying than foods. This paper discusses the results of applying microwave freeze-drying to an aqueous solution, as well as how various freezing rates affect freeze-drying characteristics. Results show that microwave freeze-drying can greatly reduce the time required to freeze-dry an aqueous solution while maintaining a high product quality. The investigation into the effects of different freezing conditions shows that different physical characteristics in the dried product can be achieved through varying the freezing rate. / Master of Science
37

Sistemas microestruturados contendo extratos de Chamomilla recutita L. para aplicações dermocosméticas / Microstructured systems containing Chamomilla recutita L. extract for dermocosmetic applications

Pereira, Simone Vieira 24 April 2015 (has links)
A Chamomilla recutita L. é uma das plantas medicinais mais cultivadas no Brasil e no mundo. Os extratos da C. recutita são de interesse para as indústrias farmacêuticas e cosméticas, visto que estes apresentam atividades anti-inflamatória, antioxidante e adstringente. A ação terapêutica do extrato pode ser mais pronunciada que a ação terapêutica de um de seus ativos isolados. No entanto, a incorporação de um extrato em uma formulação pode ser difícil devido à baixa estabilidade dos extratos, bem como à possibilidade de gerarem instabilidade das formulações. Microencapsulando o extrato com um carreador é possível aumentar estabilidade do extrato quanto evitar instabilidade na formulação. Além disso, a microencapsulação é capaz de fornecer outras vantagens, como uma liberação controlada. Dois processos foram estudados como alternativas para a microencapsulação do óleo essencial e do extrato hidroalcoólico da C. recutita usando quitosana como carreador: o spray drying e o spray freeze drying. Planejamentos fatorais foram utilizados para determinar os fatores que mais influenciaram no diâmetro médio das micropartículas, eficiência de encapsulação e teor dos marcadores e rendimento do processo. A apigenina e a apigenina-7-glicosídeo foram usadas como marcadores do extrato hidroalcoólico e o óxido de bisabolol A foi usado como marcador do óleo essencial. Os processos de spray drying e spray freeze drying dos dois extratos foram otimizados e as micropartículas resultantes foram caracterizadas com relação ao diâmetro médio, rendimento do processo, teor e eficiência de encapsulação dos marcadores, atividade antioxidante in vitro, densidade, índice de Carr, fator de Hausner, umidade, morfologia, perfil de liberação n vitro e estabilidade. Os resultados mostraram que o processo de spray drying apresentou os melhores resultados para eficiência de encapsulação, com valores de aproximadamente 98%, 95% e 80% para apigenina, apigenina-7-glicosídeo e óxido de bisabolol A, respectivamente. As eficiências de encapsulação obtidas no processo de spray freeze drying foram de aproximadamente 59%, 58% e 38% para os mesmos marcadores, respectivamente. As micropartículas produzidas por spray freeze drying apresentaram formato irregular e poroso, enquanto as produzidas por spray drying apresentaram formato esférico e superfícies mais lisas, sem poros ou fissuras. Ao contrário do que ocorreu com o extrato hidroalcoólico, a perda do marcador do óleo foi elevada no processo de spray drying, com teor final de 35%. Os teores dos marcadores ficaram acima de 80% para o processo de spray freeze drying do óleo e acima de 90% para o extrato hidroalcoólico. As micropartículas produzidas por spray drying do extrato hidroalcoólico e do óleo e por spray freeze drying do extrato hidroalcoólico e do óleo apresentaram diâmetro médio de 5,1 ?m, 5,0 ?m, 31,0 ?m e 96,4 ?m, respectivamente. Ensaios de liberação in vitro mostraram que as micropartículas foram capazes de sustentar a liberação dos respectivos marcadores. Os estudos de permeação in vitro das micropartículas produzidas por spray drying do extrato hidroalcoólico também mostraram que estas foram capazes de sustentar a liberação. A microencapsulação proporcionou em todos os casos um aumento considerável da estabilidade. As micropartículas produzidas por spray drying do extrato hidroalcoólico apresentaram teores de marcadores no mínimo 50% maiores que o extrato puro após 90 dias. O spray freeze drying se mostrou como a melhor alternativa para produção de micropartículas de quitosana contendo o óleo essencial de C. recutita, enquanto o processo de spray drying se mostrou como uma ótima alternativa para microencapsulação do extrato hidroalcoólico da C. recutita. / Chamomilla recutita L. is one of the most cultivated medicinal plants in Brazil and around the world. Its extracts are important to both the pharmaceutical and cosmetics industries due to its therapeutic applications, such as an anti-inflammatory, antioxidant, and astringent. The therapeutic effects of an extract may be more pronounced than those of an isolated active compound. However, the incorporation of an extract in a formulation is difficult due to the low stability of extracts and the potential instabilities they may cause in formulations. Microencapsulating an extract in a carrier is a potential way of increasing the stability of an extract and avoiding instabilities in a formulation. Compound microencapsulation also brings other advantages, such as controlled release rates. Two processes were studied as alternatives to microencapsulating C. recutita essential oil and C. recutita hydroalcoholic extract using chitosan as a carrier: spray drying and spray freeze drying. Factorial designs were used to determine which process factors most influence the mean diameter, encapsulation efficiency and content of the chemical markers, and process yield. Apigenin and apigenin-7-glucoside were used as chemical markers for the hydroalcoholic extract and bisabolol oxide A was used as the chemical marker for the essential oil. The spray drying and spray freeze drying processes for both the oil and hydroalcoholic extract were optimized and the resulting microparticles were further characterized to determine mean diameter, process yield, marker encapsulation efficiency and content, in vitro antioxidant activity, density, Carr index, Hausner factor, water content, morphology, in vitro release profiles and stability. The results showed spray drying had the best encapsulation efficiency results, with about 98%, 95% e 80% of the apigenin, apigenin-7-glucoside and bisabolol oxide A content, respectively, inside the microparticles. The encapsulation efficiencies obtained in the spray freeze drying process were about 59%, 58% e 38% for the same chemical markers, respectively. Microparticles produced by spray freeze drying were irregular and porous, whereas microparticles produced by spray drying were spherical and fairly smooth, without porous or cracks. Contrary to what happened with the hydroalcoholic extract, oil marker content was low for spray dried microparticles, with final content at 35%. Chemical markers contents were above 80% for the oil and above 90% for the hydroalcoholic extract in spray freeze dried microparticles. Spray dried microparticles containing extract and oil and spray freeze dried microparticles containing extract and oil had mean diameter of 5.1 ?m, 5.0 ?m, 31.0 ?m and 96.4 ?m, respectively. In vitro release profiles showed all microparticles were able to sustain their respective marker release rates. In vitro permeation studies of spray dried microparticles containing hydroalcooholic extract also showed sustained release rates for the corresponding markers. Microencapsulation also provided considerable increase in C. recutita hydroalcoholic extract stability and C. recutita essential oil stability. After 90 days spray dried microparticles containing hydroalcoholic extract presented marker content 50% higher than the pure hydroalcoholic extract. Spray freeze drying was the best alternative to produce chitosan microparticles containing C. recutita essential oil, while spray drying was shown to be an excellent way to microencapsulate C. recutita hydroalcoholic extract in chitosan.
38

Sistemas microestruturados contendo extratos de Chamomilla recutita L. para aplicações dermocosméticas / Microstructured systems containing Chamomilla recutita L. extract for dermocosmetic applications

Simone Vieira Pereira 24 April 2015 (has links)
A Chamomilla recutita L. é uma das plantas medicinais mais cultivadas no Brasil e no mundo. Os extratos da C. recutita são de interesse para as indústrias farmacêuticas e cosméticas, visto que estes apresentam atividades anti-inflamatória, antioxidante e adstringente. A ação terapêutica do extrato pode ser mais pronunciada que a ação terapêutica de um de seus ativos isolados. No entanto, a incorporação de um extrato em uma formulação pode ser difícil devido à baixa estabilidade dos extratos, bem como à possibilidade de gerarem instabilidade das formulações. Microencapsulando o extrato com um carreador é possível aumentar estabilidade do extrato quanto evitar instabilidade na formulação. Além disso, a microencapsulação é capaz de fornecer outras vantagens, como uma liberação controlada. Dois processos foram estudados como alternativas para a microencapsulação do óleo essencial e do extrato hidroalcoólico da C. recutita usando quitosana como carreador: o spray drying e o spray freeze drying. Planejamentos fatorais foram utilizados para determinar os fatores que mais influenciaram no diâmetro médio das micropartículas, eficiência de encapsulação e teor dos marcadores e rendimento do processo. A apigenina e a apigenina-7-glicosídeo foram usadas como marcadores do extrato hidroalcoólico e o óxido de bisabolol A foi usado como marcador do óleo essencial. Os processos de spray drying e spray freeze drying dos dois extratos foram otimizados e as micropartículas resultantes foram caracterizadas com relação ao diâmetro médio, rendimento do processo, teor e eficiência de encapsulação dos marcadores, atividade antioxidante in vitro, densidade, índice de Carr, fator de Hausner, umidade, morfologia, perfil de liberação n vitro e estabilidade. Os resultados mostraram que o processo de spray drying apresentou os melhores resultados para eficiência de encapsulação, com valores de aproximadamente 98%, 95% e 80% para apigenina, apigenina-7-glicosídeo e óxido de bisabolol A, respectivamente. As eficiências de encapsulação obtidas no processo de spray freeze drying foram de aproximadamente 59%, 58% e 38% para os mesmos marcadores, respectivamente. As micropartículas produzidas por spray freeze drying apresentaram formato irregular e poroso, enquanto as produzidas por spray drying apresentaram formato esférico e superfícies mais lisas, sem poros ou fissuras. Ao contrário do que ocorreu com o extrato hidroalcoólico, a perda do marcador do óleo foi elevada no processo de spray drying, com teor final de 35%. Os teores dos marcadores ficaram acima de 80% para o processo de spray freeze drying do óleo e acima de 90% para o extrato hidroalcoólico. As micropartículas produzidas por spray drying do extrato hidroalcoólico e do óleo e por spray freeze drying do extrato hidroalcoólico e do óleo apresentaram diâmetro médio de 5,1 ?m, 5,0 ?m, 31,0 ?m e 96,4 ?m, respectivamente. Ensaios de liberação in vitro mostraram que as micropartículas foram capazes de sustentar a liberação dos respectivos marcadores. Os estudos de permeação in vitro das micropartículas produzidas por spray drying do extrato hidroalcoólico também mostraram que estas foram capazes de sustentar a liberação. A microencapsulação proporcionou em todos os casos um aumento considerável da estabilidade. As micropartículas produzidas por spray drying do extrato hidroalcoólico apresentaram teores de marcadores no mínimo 50% maiores que o extrato puro após 90 dias. O spray freeze drying se mostrou como a melhor alternativa para produção de micropartículas de quitosana contendo o óleo essencial de C. recutita, enquanto o processo de spray drying se mostrou como uma ótima alternativa para microencapsulação do extrato hidroalcoólico da C. recutita. / Chamomilla recutita L. is one of the most cultivated medicinal plants in Brazil and around the world. Its extracts are important to both the pharmaceutical and cosmetics industries due to its therapeutic applications, such as an anti-inflammatory, antioxidant, and astringent. The therapeutic effects of an extract may be more pronounced than those of an isolated active compound. However, the incorporation of an extract in a formulation is difficult due to the low stability of extracts and the potential instabilities they may cause in formulations. Microencapsulating an extract in a carrier is a potential way of increasing the stability of an extract and avoiding instabilities in a formulation. Compound microencapsulation also brings other advantages, such as controlled release rates. Two processes were studied as alternatives to microencapsulating C. recutita essential oil and C. recutita hydroalcoholic extract using chitosan as a carrier: spray drying and spray freeze drying. Factorial designs were used to determine which process factors most influence the mean diameter, encapsulation efficiency and content of the chemical markers, and process yield. Apigenin and apigenin-7-glucoside were used as chemical markers for the hydroalcoholic extract and bisabolol oxide A was used as the chemical marker for the essential oil. The spray drying and spray freeze drying processes for both the oil and hydroalcoholic extract were optimized and the resulting microparticles were further characterized to determine mean diameter, process yield, marker encapsulation efficiency and content, in vitro antioxidant activity, density, Carr index, Hausner factor, water content, morphology, in vitro release profiles and stability. The results showed spray drying had the best encapsulation efficiency results, with about 98%, 95% e 80% of the apigenin, apigenin-7-glucoside and bisabolol oxide A content, respectively, inside the microparticles. The encapsulation efficiencies obtained in the spray freeze drying process were about 59%, 58% e 38% for the same chemical markers, respectively. Microparticles produced by spray freeze drying were irregular and porous, whereas microparticles produced by spray drying were spherical and fairly smooth, without porous or cracks. Contrary to what happened with the hydroalcoholic extract, oil marker content was low for spray dried microparticles, with final content at 35%. Chemical markers contents were above 80% for the oil and above 90% for the hydroalcoholic extract in spray freeze dried microparticles. Spray dried microparticles containing extract and oil and spray freeze dried microparticles containing extract and oil had mean diameter of 5.1 ?m, 5.0 ?m, 31.0 ?m and 96.4 ?m, respectively. In vitro release profiles showed all microparticles were able to sustain their respective marker release rates. In vitro permeation studies of spray dried microparticles containing hydroalcooholic extract also showed sustained release rates for the corresponding markers. Microencapsulation also provided considerable increase in C. recutita hydroalcoholic extract stability and C. recutita essential oil stability. After 90 days spray dried microparticles containing hydroalcoholic extract presented marker content 50% higher than the pure hydroalcoholic extract. Spray freeze drying was the best alternative to produce chitosan microparticles containing C. recutita essential oil, while spray drying was shown to be an excellent way to microencapsulate C. recutita hydroalcoholic extract in chitosan.
39

Freeze-drying and solubility studies.

Patel, Suresh Dahyabhai. January 1988 (has links)
The medium offering the greatest resistance to heat transfer from the freeze-drying shelf to the moving and subliming surface is the space between the flat shelf top and the concave vial bottom. The resistance to heat transfer can be greatly reduced by improving the thermal conductivity of the intervening space. Several heat transfer augmentation devices, including a multilayered corrugated aluminum quilt and a conformable fluid cushion device, which fill this gap are described. The devices are inexpensive and easy to use. Experimental data show that the resistance of the intervening space is reduced appreciably and the drying rate is greatly increased. The fluid cushion device is superior to the aluminum quilt as it reduces the consequences of spillage of solution and provides greater intervial uniformity among the same batch of vials. Drying times obtained in experiments with and without the fluid cushion device are compared here for different sizes and different types of vials. Product evaluation is conducted by measuring the reconstitution time and observing the product under a microscope. The solubilities of two univalent electrolytes, sodium chloride and potassium chloride, have been measured in eight cosolvent-water binary systems. The solubility of both the solutes has been found to be adequately described by the log-linear solubility equation, log S(m) = log S(w) + fσ. The rank order of the desolubilization slopes obtained for the electrolyte solutes is compared with the solubilization of nonelectrolyte solutes. These results indicate that a cosolvent which is most effective in solubilizing a nonelectrolyte is also most effective in desolubilizing an electrolyte. The solubility of oxacillin sodium in methanol-water mixtures has been determined at various temperatures ranging from +21 to -26 degrees centigrade. The data has been fitted to the log-linear relationship as proposed by Yalkowsky et. al. The heat of solution is determined using the van't Hoff equation and was found to be nearly constant at 1.2 Kcal/mole. There appears to be no dependency of the slope of the log S(m) vs. fraction cosolvent plot to the temperature. The data suggests that there is a polymorphic or amorphic transition of oxacillin at -14.5 degrees centigrade.
40

A novel dielectric technique for monitoring the lyophilisation of globular proteins

Suherman, Phe Man January 2001 (has links)
No description available.

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