Influence of cooling rate on the structural and phase changes during lyophilization of bovine serum albumin

A liofilização é o método mais comumente utilizado para a preparação de proteínas desidratadas, as quais devem apresentar estabilidade adequada por longo período de armazenagem em temperaturas ambientes. Entretanto, estudos recentes com espectroscopia no infravermelho têm documentado que os problemas relacionados com o congelamento e a desidratação induzidos pela liofilização podem levar ao desdobramento molecular da proteína. Através de análises por espectroscopia Raman, associadas com análise térmica por calorimetria exploratória diferencial (DSC), estudou-se a influência da taxa de congelamento no comportamento físico-químico e estrutural da albumina sérica bovina submetida ao processo de liofilização. Observou-se que a albumina liofilizada com taxa de congelamento de 2,5 °C/min apresentou maior alteração estrutural quando comparada à albumina liofilizada com taxa de congelamento de 30 °C/min, a qual apresentou menores oscilações espectrais nas regiões da amida I, III e pontes de dissulfeto, favorecendo a manutenção da conformação estrutural da proteína.Lyophilization (freeze-drying) is the most commonly method used to prepare dehydrated proteins, which should have the desired long-term stability at ambient temperatures. However, recent infrared spectroscopic studies have documented that the acute freezing and dehydration stresses of lyophilization can induce protein unfolding. Through Raman spectroscopy associated with thermal analysis using differential scanning calorimetry (DSC), it was studied the influence of cooling rate on the structural and phase changes during lyophilization of bovine serum albumin. It was observed that bovine serum albumin (BSA) lyophilized under slow freezing (2.5 ºC/min) presented higher structure damage than the BSA lyophilized under fast freezing (30 ºC/min) However, the lyophilization process using cooling rate of 30 ºC/min presented fewer spectra alterations on the Amide I, III and disulfide bridges, supporting the maintenance of protein structural conformation

Gestão de Componentes em Dinâmico

A crescente evolução das tecnologias de informação e comunicação, aliadas ao desenvolvimento industrial, proporcionou um aumento de competitividade entre as indústrias, originando uma subida do nível da relação qualidade preço. Esta premissa causou uma maior preocupação com a procura contínua pela melhoria dos processos, de forma a aumentar as actividades de valor acrescentado, eliminando todo o tipo de desperdícios. Nesta conjuntura, a Grohe Portugal Componentes Sanitários, Lda propôs uma melhoria no âmbito da gestão de stocks de componentes existentes em dinâmico. Esta acção de melhoria passa pela definição e implementação de um método de gestão destes componentes, acompanhado por um conjunto de regras de identificação de actividades e respectivos intervenientes, por forma a optimizar os meios existentes e evitar a ocorrência de falhas de componentes nas linhas. Trata-se de um método baseado no cálculo das necessidades das linhas, que através da procura média semanal e constituição dos produtos finais define um nível de prioridade entre os componentes, identificando quais os mais requisitados pelas linhas e possibilitando a gestão do dinâmico. Na contínua tentativa de combater possíveis falhas, desenvolveu-se um sistema de gestão do tipo Kanban com a capacidade de gerir o produto semi-acabado para consumo interno. Foram, ainda, criadas melhorias que permitem um acréscimo de eficiência na gestão dos componentes em estante dinâmica, diminuindo o capital imobilizado investido em stocks, levando a um rearranjo de layouts, proporcionando melhores condições de trabalho e optimizando percursos e recursos. Descreve-se detalhadamente o processo de (i) actualização, definição e implementação do método de gestão de componentes em dinâmico, acompanhado pelo respectivo conjunto de regras, (ii) a implementação de um sistema do tipo Kanban orientado às reais preocupações da empresa, (iii) a redefinição de layouts em conformidade com a actualização dos dinâmicos e (iv) a identificação e execução de um conjunto de melhorias. Todas estas actividades acompanhadas pelo impacto financeiro na organização. Por fim, efectua-se o balanço deste projecto e sugerem-se oportunidades de melhoria.The growing evolution of information and communication technologies, allied to the industrial development, provided an increase of competitive edge between the industries, originating a rise in the level of quality price relationship. This premise caused a bigger concern with the continuous search for processes improvement, in order to increase the activities of added value, eliminating all kind of waste. In this conjuncture, Grohe Portugal Componentes Sanitários, Lda proposed na improvement in the scope of stocks management of existing components in dynamic shelfs. This action of improvement goes by the definition and implementation of a management method of these components, accompanied by a set of rules of activity identification and respective stakeholders, in such a way to optimize the existing means and avoid the shortage of the components in the production lines. It is a method based in the calculation of the lines needs, that through the weekly average search and final products constitution defines a priority level between components, identifying which is the most required by the lines and allowing the dynamics management. In the continuous attempt to counter possible failures, it was developed a management system of Kanban type with the capacity of managing the semi-finished product for internal consumption. There were, still, created improvements that allow an increase of efficiency in the management of components in a dynamic shelf, decreasing the immobilized capital invested in stocks, leading to a rearrangement of layouts, providing better working conditions and optimizing pathways and resources. It is described in detail the process of (i) update, definition and implementation of the management method of dynamic shelfs components, accompanied by the respective set of rules, (ii) the implementation of a Kanban type system guided to the real concerns of the company, (iii) the redefinition of layouts in conformity with the dynamics update and (iv) the identification and execution of a set of improvements. All of these activities are accompanied by the financial impact on the organization. Lastly, the balance of this project is done and are suggested some opportunities to improve it

Polymer matrix sensitizing effect on photoluminescence properties of Eu(3+)-beta-diketonate complex doped into poly-beta-hydroxybutyrate (PHB) in film form

In this work is reported the sensitization effect by polymer matrices on the photoluminescence properties of diaquatris(thenoyltrifluoroacetonate)europium(III), [Eu(tta)(3)(H(2)O)(2)], doped into poly-beta-hydroxybutyrate (PHB) with doping percentage at 1, 3, 5, 7 and 10% (mass) in film form. TGA results indicated that the Eu(3+) complex precursor was immobilized in the polymer matrix by the interaction between the Eu(3+) complex and the oxygen atoms of the PHB polymer when the rare earth complex was incorporated in the polymeric host. The thermal behaviour of these luminescent systems is similar to that of the undoped polymer, however, the T(onset) temperature of decomposition decreases with increase of the complex doping concentration. The emission spectra of the Eu(3+) complex doped PHB films recorded at 298 K exhibited the five characteristic bands arising from the (5)D(0) -> (7)F(J) intraconfigurational transitions (J = 0-4). The fact that the quantum efficiencies eta of the doped film increased significantly revealed that the polymer matrix acts as an efficient co-sensitizer for Eu(3+) luminescent centres and therefore enhances the quantum efficiency of the emitter (5)D(0) level. The luminescence intensity decreases, however, with increasing precursor concentration in the doped polymer to greater than 5% where a saturation effect is observed at this specific doping percentage, indicating that changes in the polymeric matrix improve the absorption property of the film, consequently quenching the luminescent effect.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Rede de Nanotecnologia Molecular e de Interfaces (RENAMI)Instituto do Milenio de Materiais Complexos (IM<SUP>2</SUP>C

Influência da taxa de congelamento no comportamento físico-químico e estrutural durante a liofilização da albumina bovina Influence of cooling rate on the structural and phase changes during lyophilization of bovine serum albumin

A liofilização é o método mais comumente utilizado para a preparação de proteínas desidratadas, as quais devem apresentar estabilidade adequada por longo período de armazenagem em temperaturas ambientes. Entretanto, estudos recentes com espectroscopia no infravermelho têm documentado que os problemas relacionados com o congelamento e a desidratação induzidos pela liofilização podem levar ao desdobramento molecular da proteína. Através de análises por espectroscopia Raman, associadas com análise térmica por calorimetria exploratória diferencial (DSC), estudou-se a influência da taxa de congelamento no comportamento físico-químico e estrutural da albumina sérica bovina submetida ao processo de liofilização. Observou-se que a albumina liofilizada com taxa de congelamento de 2,5 &deg;C/min apresentou maior alteração estrutural quando comparada à albumina liofilizada com taxa de congelamento de 30 &deg;C/min, a qual apresentou menores oscilações espectrais nas regiões da amida I, III e pontes de dissulfeto, favorecendo a manutenção da conformação estrutural da proteína.<br>Lyophilization (freeze-drying) is the most commonly method used to prepare dehydrated proteins, which should have the desired long-term stability at ambient temperatures. However, recent infrared spectroscopic studies have documented that the acute freezing and dehydration stresses of lyophilization can induce protein unfolding. Through Raman spectroscopy associated with thermal analysis using differential scanning calorimetry (DSC), it was studied the influence of cooling rate on the structural and phase changes during lyophilization of bovine serum albumin. It was observed that bovine serum albumin (BSA) lyophilized under slow freezing (2.5 ºC/min) presented higher structure damage than the BSA lyophilized under fast freezing (30 ºC/min) However, the lyophilization process using cooling rate of 30 ºC/min presented fewer spectra alterations on the Amide I, III and disulfide bridges, supporting the maintenance of protein structural conformation

The influence of crucible material on the DSC thermal analysis compared to freeze-drying microscopy results

The aim of this study was to investigate the influence of different crucible materials on the thermal analysis of binary systems. The thermal properties of two distinct solutions were measured both by Differential Scanning Calorimetry (DSC) and freeze-drying microscopy and the results were compared. The glass transition of the maximally freeze-concentrate (T (g)`) and the eutectic melting temperature (T (eut)) were not influenced by the crucible material. However the heat of fusion (Delta H) involved during the T (eut) as well as the Delta C (p) involved during the T (g)` of the solutions were affected.FAPESP (The State of Sao Paulo Research Foundation)CNPq (National Council for Scientific and Technological Development

Calorimetric investigations of luminescent films polycarbonate (PC) doped with europium complex [Eu(TTA)(3)(H(2)O)(2)]

Polymers doped with rare earth complexes are advantaged in film production for many applications in the luminescent field. In this luminescent polycarbonate (PC) films doped with diaquatris(thenoyltrifluoroacetonate)europium(III) complex [Eu(TTA)(3)(H(2)O)(2)] were prepared and their calorimetric and luminescent properties in the solid state are reported. The thermal behavior was investigated by utilization of differential scanning calorimetry (DSC) and thermogravimetry (TG). Due of the addition of rare earth [Eu(TTA)(3)(H(2)O)(2)] into PC matrix, changes were observed in the thermal behavior concerning the glass transition and thermal stability. Characteristic broadened narrow bands arising from the (5)D(0) -> (7)F(J) transitions (J = 4-0) of Eu(3+) ion indicate the incorporation of the Eu(3+) ions in the polymer. The luminescent films show enhancement emission intensity with an increase of rare earth concentration in polymeric matrix accompanied by decrease in thermal stability.IPEN/CNEN-SP (Nuclear and Energetic Research Institute, National Commission of Nuclear Energy)IPEN/CNEN-SP (Nuclear and Energetic Research Institute, National Commission of Nuclear Energy)Eleosmar Gasparin, Department of Fundamental Chemistry from Chemistry Institute, University of Sao Paulo (USP), BrazilEleosmar Gasparin, Department of Fundamental Chemistry from Chemistry Institute, University of Sao Paulo (USP), BrazilConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPQ[303322/2006

Solid–liquid equilibrium of binary and ternary systems formed by ethyl laurate, ethyl palmitate and n-decane: Experimental data and thermodynamic modeling

The solid liquid equilibrium phase diagrams of binary and ternary mixtures formed by n-decane and the fatty acid ethyl esters ethyl laurate and ethyl palmitate were studied through differential scanning calorimetry (DSC). Phase change properties of polymorphs were obtained by resolving the thermograms into the corresponding overlapping peaks through a fitting analysis with a Gaussian function. The binary systems show immiscibility in solid phase. The system formed by ethyl laurate and n-decane presents two peritectic transformations, which were also observed in the ternary phase diagram. Equilibrium data were thermodynamically modeled using different models for liquid phase non-ideality and considering different polymorphs in solid phase. The results of modeling are in good agreement with the eutectic behavior of the system formed by ethyl palmitate and n-decane. However, higher discrepancies were observed if no peritectic behavior for the binary system formed by ethyl laurate and n-decane is considered. The results obtained in this work constitute another step forward to enhance the understanding and description of the complex behavior of biodieselidiesel mixtures at low temperatures426SI8394CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP150950/ 2014-42010/18355-1; 2008/56258-810th Iberoamerican Conference on Phase Equilibria and Fluid Properties for Process Design (EQUIFASE)2015Alicante, Espanh