Thesis (Ph.D.) - University of St Andrews, January 2008.

Orientador: Prof.Dr.Arnaldo Rodrigues dos Santos Jr / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Biotecnociência, 2016. / A rotofiação é uma técnica recente que surgiu para melhorar a taxa de produção de fibras que podem ser usadas na regeneração ou cicatrização tecidual. Existe um interesse crescente no desenvolvimento de matrizes poliméricas com o objetivo de auxiliar a cicatrização.Foi utilizadas soluções poliméricas compostas por PCL/PLLA (50/50%) com e sem tetraciclina (TC), nas concentrações de 3%, 5%, 7%(m/v) dissolvidos em clorofórmio e uma variação produzida com 5% (m/v) utilizando 20% de acetona e 80% de clorofórmio como solventes, que denominamos de 20:80(v/v). As soluções foram padronizadas em volume de 10ml para serem rotofiadas e formaram fibras e membranas, fato não relatado na literatura. Constatou-se que a produção aumenta juntamente coma utilização de soluções poliméricas mais concentradas, visto que a solução 3% não produziu fibras e a 7% foi a que resultou em maior quantidade. O teste de viscosidade demonstrou a relação direta entre o aumento da viscosidade com o aumento da concentração de polímero. A TC interferiu na morfologia das membranas e fibras, tanto na porosidade quanto na espessura. Na análise de espessura das membranas foi verificado que as soluções mais viscosas produzem membranas mais espessas. A espectroscopia no infravermelho por transformada de Fourier (FTIR) no módulo de refletância total atenuada (ATR) demonstrou picos característicos de PCL/ PLLA e TC. O microscópio invertido de fluorescência foi utilizado para análise de incorporação e quantificação da TC, a incorporação da TC foi confirmada pela emissão de fluorescência somente nas amostras contendo TC. A análise microbiológica foi realizada em cultura de bactérias Staphylococcus aureus em todas as membranas e somente na fibra 7%, no teste em placas de Petri a formação de halo de inibição representou a atividade antibacteriana em todas as amostras, um teste de diluição em caldo foi realizado e confirmou o resultado somente nas membranas com TC, as fibras não mostraram capazes de matar as bactérias.Foram feitos 2 testes de citotoxicicidade, o primeiro com células inoculadas diretamente sobre o material por um período de 48h mostrou que as amostras com TC eram tóxicas, o segundo foi realizado um tratamento retirando o excesso de TC sobrenadante e apresentou resultado oposto nas membranas, com formação de tapete celular em todas as amostras, exceto nas fibras 7%T, indicando que a morte celular ocorria pelo excesso de TC liberada num primeiro momento nas membranas, porém, nas fibras esse tratamento não foi eficaz. A análise citoquímica mostrou a presença de células em todas as membranas e nas fibras 7% controle, porém, notamos ausência de células nas fibras 7%T corroborando com a citotoxicidade apresentada. Os resultados indicam que a técnica de rotofiação produz fibras e membranas com alta porosidade utilizando baixas concentrações de polímeros, em quantidades satisfatórias para as fibras a partir da concentração de 7%. A concentração de TC necessita de ajuste para excluir a citotoxicidade. As amostras controles não apresentaram citotoxicidade sendo indicadas para testes in vivo. Este trabalho pretende colaborar com as poucas informações sobre a técnica de rotofiação. / The centrifugal spinning is a recent technique that has emerged for improving the production of fibers which can be used in tissue regeneration or healing. There is growing interest in the development of polymer matrices in order to promote the wound healing mainly due to the limitations of available products. Polymer solutions composed of PCL/PLLA (50/50%) with and without tetracycline (TC) were used in the concentrations of 3%, 5%, 7% (m/v) dissolved in chloroform and a variation produced with 5% (m/v) using 20% acetone and 80% chloroform as solvents, which we call 20:80 (v/v). The solutions were standardized in 10 ml volume to be rotofied and formed fibers and membranes, which has not yet been reported in the literature. It was found that the production increases along with the use of more concentrated polymer solutions, since the 3% solution did not produce fibers and 7% resulted in higher amounts. The viscosity test demonstrated a direct relationship between increasing viscosity with increasing polymer concentration. CT interfered in the morphology of membranes and fibers, both in porosity and thickness. In the analysis of the thickness of the membranes it was verified that the more viscous solutions produce thicker membranes. Fourier transform infrared spectroscopy (FTIR) in the attenuated total reflectance (ATR) module demonstrated characteristic peaks of PCL/PLLA and TC. The fluorescence inverted microscope was used for CT incorporation and quantification analysis, the TC incorporation was confirmed by the emission of fluorescence only in samples containing TC. Microbiological analysis was performed on culture of Staphylococcus aureus bacteria in all membranes and only on 7% fiber, in the Petri dish test the inhibition halo formation represented antibacterial activity in all samples, a broth dilution test was Performed and confirmed the result only on TC membranes, the fibers were not able to kill the bacteria. Two cytotoxicity tests were performed, the first with cells inoculated directly on the material for a period of 48h showed that the TC samples were toxic, the second was a treatment removing the excess TC presented opposite result in the membranes, with Cell carpet formation in all samples, except for the 7%T fibers, indicating that cell death occurred due to the excess of TC released at the first moment in the membranes, but in the fibers this treatment was not effective. Cytochemical analysis showed the presence of cells in all membranes and in the 7% control fibers, however, there were no cells in the fibers 7% T corroborating with the presented cytotoxicity. The results indicate that the rotofiation technique produces membranes and fibers with high porosity using low concentrations of polymers, in quantities satisfactory to the fibers from the concentration of 7%. TC concentration needs adjustment to exclude cytotoxicity. Control samples did not show cytotoxicity being indicated for in vivo testing. This work intends to collaborate with the few information about rotofiação technique.

Orientador: Prof. Dr. Jean-Jacques Bonvent / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Biotecnociência, 2017.

A indústria têxtil tem sido responsável pela criação de novos materiais e pela busca de modernização dos seus processos. A utilização do pelo de poodle trata-se de uma alternativa para diminuir a quantidade de pelos descartados em pet shops, por meio da reciclagem desses resíduos. A coleta dos pelos deve seguir certas normas criadas pela Vigilância Sanitária, que obriga os pet shops a pagarem pelo seu descarte. A utilização desse pelo, além de criar a possibilidade de uma engenharia reversa, também permitiria um descarte mais útil e sustentável. O objetivo deste trabalho foi apresentar procedimentos para verificar a viabilidade de utilização das fibras de pelo de poodle na fabricação de fios têxteis. As fibras de poodle foram coletadas na cidade de São Paulo e separadas em três lotes: claro, castanho e escuro. Visando simular as condições de mercado, parte dos três lotes de fibras foram homogeneizados, manualmente, em um único lote, que recebeu o nome de mescla. Através dos ensaios de microscopia das fibras de poodle, foi possível verificar a semelhança destas com a lã do carneiro. Para tornar possível a comparação entre as fibras, foram selecionadas no mercado dois tipos de lã 36s e 56s e realizados, nos seis tipos de fibras, os ensaios físicos de finura, módulo de Young, tenacidade e alongamento. A análise dos resultados foi feita utilizando as ferramentas estatísticas análise de variância (ANOVA), com intervalo de confiança de 95%, e o box plot. Os resultados obtidos indicam a viabilidade tanto do uso do pelo de poodle para a fabricação de fios têxteis, quanto da aplicação da metodologia proposta / The textile industry has been responsible for the creation of new materials and for the search for streamlining their processes. The use of the poodle hair is an alternative to reduce the amount of the dog hair discarded in pet stores, through recycling of the waste. The collection of this kind of waste must follow certain standards developed by the Health Surveillance, requiring the pet shops to pay for the disposal service. The use of this kind of dog hair, in addition to create the possibility of reverse engineering, would also provide a more useful and sustainable disposal of it. The aim of this paper is to present procedures to verify the feasibility of poodle hair fibers in the manufacture of textile yarn. The poodle fibers were collected in São Paulo and separated into three lots: clear, brown and dark. In order to simulate the market conditions, the three lots of fibers were homogenized by hand in a single batch, which was named mixture. Through microscopy testing of poodle fibers was possible to verify the similarity of these fibers with sheep\'s wool. To allow comparison between the fibers, two types of wool have been selected in the market 36\'s and 56\'s and it have been performed, on six types of fibers, the physical tests of fineness, Young\'s modulus, toughness and elongation. The analysis was conducted by using the statistical tools of analysis of variance (ANOVA), with a 95% confidence interval, and the box plot. The results indicate the feasibility of both the poodle hair for the manufacture of textile yarns, and the use of the proposed methodology

Today, there are only a limited number of surveys of the sky at 1 to 20 GHz. These frequencies lie below the all-sky surveys of WMAP and Planck, but are critical in constraining the spectral slope of Galactic synchrotron emission. Knowledge of the large-scale spectral morphology of Galactic synchrotron emission is critical in the understanding of the interstellar medium and the weak signal from the polarised cosmic microwave background. Recently, ground based observations from S-PASS, C-BASS and the QUIJOTE Multifrequency Instrument (MFI) have been populating these missing frequencies. This thesis presents the first QUIJOTE MFI maps of the Northern sky in total intensity at 11, 13, 17 and 19 GHz, and the first single-dish mapping observations of Lynds dark cloud, LDN1622 at 5 and 13.7GHz. The observations from both instruments are used to probe the nature of spinning dust emission on degree and arcminute scales within the Galaxy. A full data reduction and calibration pipeline for QUIJOTE MFI time-ordered-data is described. The absolute flux density scale uncertainty of the MFI data is between 2 and 3 per cent. The pipeline characterises key properties of the MFI, such as the RFI sources, beams, bandpasses, 1/f noise and more. A key part of the pipeline was the development of an MPI ready Destriping map-maker and a maximum-likelihood map-maker. The map-making code can be applied to a range of different single-dish instruments and is used to reduce both the QUIJOTE MFI wide-survey maps of the Northern sky, and the GBT arcminute resolution raster observations of LDN 1622. A detailed discussion is given on the simulations used to test the integrity of the map-making implementation. Parametric model fitting to the SEDs of four spinning dust emission regions is performed. The MFI wide-survey maps are used in conjunction with existing multifrequency 1degree survey data. The addition of MFI maps is used to confirm the previously tentative spinning dust emission source LDN 1582/84. The mean peak frequency of spinning dust emission over the four spinning dust sources is found to be ⟨νsp⟩ = 27.2 +/- 0.7 GHz, and the mean ratio of the peak spinning dust brightness over the dust optical depth is ⟨Asp/τ250⟩ = 1.24 +/- 0.18 × 104 Jy/τ250. Spectral index maps are derived from the MFI wide-survey data in combination with 408 MHz and WMAP 23 GHz data. These maps are used to further quantify the ubiquity of spinning dust emission throughout the Galaxy. The results show that the median flux density spectral index within the inner Galactic disk for |b| < 2° is 0.24 +/- 0.07. This implies that at 23 GHz, spinning dust emission contributes 25 +/- 5 per cent of the total integrated emission within the inner disk of the Galaxy.

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The presented dissertation thesis deals with the polymer polyhydroxybutyrate and other biopolymers as a basic building block for the construction of micro- and nanoscopic structures and materials used in food and cosmetics. In the theoretical part, current literary review is prepared to introduce the basics of this application field. The practical part of the work is composed of three blocks developed during the doctoral study. In the first and most important part are summarized comments to the academic and patent outputs, where among the academic ones it is possible to find two peer-reviewed articles dealing with the electrostatic and wet spinning of PHB and properties of prepared materials. The patent outputs consist of several accepted and applied projects, which summarize results on both PHB spinning methods, but also on general approaches enabling the processing of PHB into forms enabling many applications in food and cosmetics. Second part was focused on the patented composition of the UV protection cream based on the prepared nanoscopic and micro- morphologies of PHB. The third block summarizes results focused predominantly on the electrostatic spinning of PHB and other biopolymers. Finally, a short chapter containing a brief description of projects that were in a way related to the dissertation topic, but rather practical development work in Central Tanzania and West Africa, which draw on knowledge and contacts gained during studies at FCH BUT Brno.

Diplomová práca je zameraná na mikrovlákna na báze biopolyméru poly(3-hydroxybutyrátu) a ich využitie v medicínskych aplikáciách. Teoretická časť práce sa zaoberá štúdiom procesu tvorby vláken pomocou technológie odstredivého zvlákňovania, jeho kinetikou a faktormi ovplyvňujúcimi vznik a vlastnosti vláken. Teoretická časť sa následne orientuje na krátky prehľad biopolymérov používaných v tejto technológii, charakteristiku materiálu poly(3-hydroxybutyrátu) a taktiež prezentuje návrh potenciálnej cieľovej aplikácie daných mikrovláken. Praktická časť sa koncentruje sa prípravu mikrovláken zo spomínaného poly(3-hydroxybutyrátu). Sledované a optimalizované sú viaceré parametre vedúce k lepšej zvlákniteľnosti materiálu. Praktická časť je rozšírená o modifikáciu polymérneho roztoku prídavkom iných biopolymérov a zmäkčovadiel a prípravu mikrovláken z takto modifikovanej polymérnej zmesi. Pozornosť je venovaná taktiež optimalizácii procesných parametrov. Pripravené mikrovlákna sú následne analyzované a charakterizované viacerými metódami a vzájomne porovnávané s cieľom vyvinúť alternatívu k súčasne používaným substrátom pre rast buniek v 3D.

The thesis deals with the principal heating design of the electrospinning electrode. These electrodes are fed with high voltage (tens of kV), which is an essential part of the device for the nanofibres production. This thesis presents the research of possible solutions of the heating and also it analyzes some principles of the nanofibre production. Furthermore, the work presents electrical schematics and PCB of the heating module. The aim of this work is to propose such a solution of heating that makes spinning from melt realizable in the device for 4SPIN ® nanofibres production.