Desenvolvemos um instrumento capaz de provocar uma lesão muscular aguda por mecanismo de impacto, no músculo gastrocnêmio de ratas, através de um trauma direto e não-invasivo. Após a produção da lesão experimental avaliamos os efeitos do ultra-som terapêutico (UST), adicionado ou não à imobilização gessada, como forma de tratamento imediato à lesão muscular pela análise das propriedades mecânicas deste músculo. Foram utilizadas 68 ratas da raça Wistar, sendo divididas em 7 grupos experimentais da seguinte forma: Grupo 1 – Controle intacto; Grupo 2 – Sem tratamento efetivo, Grupo 3 – Imobilização gessada por 24 horas; Grupo 4 – Imobilização gessada por 72 horas; Grupo 5 – Estimulação com UST sem presença de imobilização; Grupo 6 – Imobilização gessada por 24 horas associada à estimulação com UST; Grupo 7 – Imobilização gessada por 72 horas associada à estimulação com UST tratadas durante 6 dias consecutivos com UST, durante 5 minutos diários. Avaliamos as propriedades mecânicas obtidas através de ensaios mecânicos de tração longitudinal e os resultados foram analisados estatisticamente. O estudo evidenciou que a propriedade de alongamento no limite de proporcionalidade não foi um bom parâmetro de correlação para avaliar a efetividade dos tratamentos empregados junto ao processo de reparação muscular. A utilização isolada do UST como técnica de tratamento apresentou melhores resultados em relação às propriedades mecânicas de carga no limite de proporcionalidade, rigidez, resiliência, carga e alongamento máximo. No entanto, a utilização da imobilização gessada por 72 horas associada ou não a estimulação ultra-sônica foi capaz de proporcionar melhorias somente em relação ao alongamento máximo. Sugere-se ainda, que a utilização da imobilização gessada por períodos de 24 horas associada ou não ao uso do UST não foi capaz de apresentar resultados benéficos para as propriedades mecânicas avaliadas / We developed an instrument capable to provoke a muscular injury acute for impact mechanism, in the muscle gastrocnemius of female rats, through a direct and non-invasive. After the production of experimental injury we evaluate the effects of the therapeutic ultrasound (UST), added or not to the cast immobilization, as form of immediate treatment to the muscular injury, for the analysis of the mechanical properties of this muscle. Sixty eight female Wistar rats were used and being divided in seven experimental groups: Group 1 – Intact Control; Group 2 – Without treatment; Group 3 -Immobilization in spica cast for 24 hours; Group 4 - Immobilization in spica cast for 72 hours; Group 5 – Stimulation with UST without immobilization presence; Group 6 - Immobilization in spica cast for 24 hours associated to the stimulation with UST and Group 7 - Immobilization in spica cast for 72 hours associated to the stimulation with UST, treated during six consecutive days with UST, for five minutes daily. We evaluted properties we carry through assays of logitudinal traction in the universal machine of assays and the gotten results had been analyzed statical test. The study it evidenced that the property of proportional limit strength in the was not a good parameter of correlation to evaluate the effectiveness of the employed treatments together to the process of muscular repairing. The isolated use of the UST as treatment technique presented better resulted in relation to the mechanical load properties in the proportional limits, stiffness, resilience, load and strength maximum. However, the use of the spica cast for periods of 72 hours associated or not ultrasound stimulation was not capable to only provide improvements in relation to the maximum strength. One still suggests, that the use of the spica cast in the immobilization for 24 hours periods associate or not to the use of the UST was not capable to present resulted beneficial for the evaluated mechanical properties

Melanina é um polímero constituído por uma grande heterogeneidade de monômeros tendo como característica comum a presença de grupos indóis. Por outro lado, a eumelanina produzida pela oxidação enzimática da tirosina é um polímero mais simples constituído principalmente de monômeros 5,6-dihidroxindol (DHI) e de indol-5,6-quinona (IQ). Tirosinase é a enzima chave na produção de melanina, sendo que a sua atividade cinética é medida em função da formação do intermediário dopacroma. Nanopartículas (NPs) de sílica são partículas nanométricas compostas de oxido de silício e são obtidas pelo processo sol-gel desenvolvido por Stöber de hidrólise e condensação de tetraetilortosilicato (TEOS), usando etanol como solvente em meio alcalino. As NPs foram funcionalizadas com 3-Aminopropiltrietoxissilano (ATPES) e depois com glutaraldeído. Este último permitiu a imobilização da tirosinase na superfície da sílica. Caracterizamos as NPs antes e após a reação da enzima, a atividade catalítica da enzima ligada à NP e o mecanismos de formação de melanina na superfície da sílica. As NPs foram caracterizadas por espectrofotometria de absorção e de reflectância, termogravimetria e microscopia eletrônica. A síntese da NP de sílica retornou partículas esféricas com 55nm de diâmetro e a funcionalização da partícula mostrou modificar eficientemente a sua superfície. A imobilização da tirosinase por ligação covalente foi de 99,5% contra 0,5% da adsorção física. A atividade da tirosinase foi caracterizada pela formação de dopacroma. O Km da enzima imobilizada não sofreu alteração em comparação com a tirosinase livre, mas a eficiência catalítica - que considera a eficiência recuperada - foi de apenas 1/3 para a enzima ligada covalentemente, significando que 2/3 das enzimas ligadas não estão ativas. Obtivemos NPs revestidas com melanina a partir de oxidação de tirosina solubilizada em duas preparações: NP com tirosinase ligada covalentemente na superfície e NP funcionalizada com glutaraldeido dispersa em solução de DHI e IQ. O revestimento de melanina foi na forma de um filme fino com espessura ~1,9nm, conferindo perfil de absorção luminosa equivalente ao da própria melanina. Mostramos que o mecanismo de polimerização passa pela oxidação da tirosina pela tirosinase, que gera intermediários oxidados (principalmente DHI e IQ) que vão para solução (mesmo quando a tirosinase está ligada covalentemente na sílica). Estes intermediários ligam-se ao glutaraldeido e a superfície da sílica passa a funcionar como ambiente de polimerização da melanina. / Melanin is a polymer consisting of a large heterogeneity of monomers having as a common feature the presence of indole groups. Contrarily, eumelanin produced by enzymatic oxidation of tyrosine is a simpler polymer consisting mainly of 5,6-dihidroxindol (DHI) and indole-5,6-quinone (IQ) monomers. Tyrosinase is the key enzyme in melanin production, and its kinetic activity is measured by the formation of the intermediate dopacroma. Nanoparticles (NPs) are made of silica nanoparticles of silicon oxide and are obtained by sol-gel method developed by Stöber of hydrolysis and condensation of tetraethylorthosilicate (TEOS), using ethanol as solvent in an alkaline medium. NPs were functionalized with 3-Aminopropyltriethoxysilane (ATPES) and then with glutaraldehyde. The latter allows the immobilization of tyrosinase on the silica surface. We characterized NPs before and after the reaction of the enzyme, the catalytic activity of the enzyme bound to the NP and melanin-forming mechanisms on the silica surface. NPs were characterized by absorption spectrophotometry and reflectance, electron microscopy and thermogravimetric analysis. The synthesis of silica NP returned spherical particles of 55nm diameter and particle functionalization showed efficiently modify its surface. The immobilization of tyrosinase by covalent bond was 99.5% versus 0.5% by physical adsorption. The activity of tyrosinase was characterized by the formation of dopacroma. The Km of the immobilized enzyme did not change compared to the free tyrosinase, but the catalytic efficiency - considering the recovered efficiently - was only 1/3 for the enzyme covalently bound, meaning that 2/3 of the enzymes are not connected active. We obtained melanin coated NPs from tyrosine oxidation in two preparations: NP with covalently bound tyrosinase in the NP surface and NP functionalized with glutaraldehyde dispersed in DHI and IQ solution. The melanin coating was in the form of a thin film with the thickness of ~ 1,9 nm, giving light absorption profile equivalent to that of melanin itself. We showed that the polymerization mechanism involves the oxidation of tyrosine by tyrosinase, which generates oxidized intermediates (especially DHI and lQ) that go into solution (even when tyrosinase is covalently bound to the silica). These intermediates bind the glutaraldehyde and the surface of the silica begins to function as an environment for melanin polymerization.

Les azométhines contiennent des liaisons covalentes qui peuvent se former de façon réversible entre une amine et un aldéhyde. Cette réversibilité peut être exploitée pour échanger leurs composantes constitutionnelles. Les propriétés intrinsèques des azométhines peuvent être modulées en échangeant les composantes amines ou aldéhydes. L’échange des composantes constitutionnelles est possible en solution. Toutefois, les produits échangés doivent être purifiés pour éliminer les divers réactifs et produits échangés indésirables. Il est donc avantageux de simplifier l’étape de purification pour isoler le produit échangé désiré. Un moyen possible pour atteindre cet objectif est d’immobiliser l’amine ou l’aldéhyde sur une surface. Dans ce cas, les produits échangés souhaités peuvent être facilement isolés en rinçant la surface à la suite de cet échange. À cette fin, un monomère d’aldéhyde électroactif dérivé de la triphénylamine a été préparé. Il a été polymérisé thermiquement sur une électrode transparente. La polymérisation a été confirmée par les spectroscopies FT-IR ATR et Raman. Une série d’amines (aminocoumarines et diaminobenzothiadiazole) présentant chacune une couleur unique, une longueur d’émission et un potentiel d’oxydation électrochimique ont été choisis. Leur formation en azométhine et leur échange dynamique sur film mince d’aldéhyde électroactif ont donc pu être suivis électrochimiquement, par des spectroscopies UV-visibles et Raman, et par la fluorescence. Des composés modèles de ces fluorophores azométhines ont également été préparés pour l’analyse comparative de leurs propriétés électrochimiques et spectroscopiques, ainsi que pour la confirmation de l’échange des composantes. Il a été montré que les propriétés multiples (potentiel redox, couleur, longueur d’onde et rendement d’émission) du film électroactif pouvaient être simultanément modulées par la formation réversible d’azométhine. En immobilisant les azométhines sur une surface, leurs propriétés pourraient être modifiées de façon réversible par échange des composantes, soit en immergeant le substrat dans une solution d’amine, soit en enduisant la surface d’un jet d’amine suivi d’un rinçage. Ce processus direct permet de développer des surfaces dont les propriétés peuvent être constamment modifiées, tout en ouvrant la possibilité de réparer la surface et de restaurer les propriétés souhaitées par un échange dynamique de composantes. / Azomethines incorporate covalent bonds that can be reversibly formed between an amine and aldehyde. This reversibility can be exploited to exchange their constitutional components. The intrinsic properties of the azomethines can be modulated by exchanging either the amine or the aldehyde components. Exchanging the constitutional components is possible in solution. However, the exchanged products must be purified to remove the various reagents and undesired exchanged products. It is therefore advantageous to simplify the purification step for isolating the desired exchanged product. A possible means towards this goal is by immobilizing either the amine or the aldehyde on a surface. In such a case, the desired exchanged products can be readily isolated by rinsing the surface following the dynamic component exchange. Towards this end, an electroactive aldehyde monomer derived from triphenylamine was prepared. It was thermally polymerized on a transparent electrode. Polymerization was confirmed by FT-IR ATR and Raman spectroscopies. A series of amines (aminocoumarin and diaminobenzothiadiazole) each with a unique color, emission wavelength and electrochemical oxidation potential were chosen. Their azomethine formation and dynamic exchange with the electroactive aldehyde thin film could therefore be tracked electrochemically, by UV-visible and Raman spectroscopies, and by fluorescence. Model compounds of these azomethine fluorophores were also prepared for benchmarking their electrochemical and spectroscopic properties along with confirming component exchange. It was shown that multiple properties (redox potentials, color, emission wavelength, and emission yield) of the electroactive film could be simultaneously modulated by reversible azomethine formation. By immobilizing the azomethines on a surface, their properties could be reversibly modified by component exchange by either dipping the substrate in an amine solution or coating the surface with a spray of amine followed by rinsing. This straight-forward process provides the means for developing surfaces whose properties can be perpetually modified, while opening the possibility of repairing the surface and restoring desired properties by dynamic component exchange.

<p>Predmet istraživanja ove disertacije je mogućnost kori&scaron;ćenja nano nula<br />valentnog gvožđa stabilizovanog sa bentonitom, kaolinitom i karboksimetil<br />celulozom za imobilizaciju te&scaron;kih metala, kao i pona&scaron;anje i sudbina metala u<br />sedimentu. Istraživanja je usmero u dva pravca: prvi deo istraživanja ima za cilj,<br />pre svega da defini&scaron;e bolje razumevanje pona&scaron;anja metala u sedimentu i<br />određivanje njihove potencijalne mobilnost, biodostupnost i potencijalne<br />toksičnost na osnovu metoda sekvencijalne ekstrakcione procedure, kiselo<br />volatilnog sulfida i simultano ekstrahovanih metalau netretiranim i tretiranim<br />uzorcima sedimenta. Takođe, određena je efikasnosti kori&scaron;ćenja nanomaterijala<br />za imobilizaciju metala u sedimentu iz tretiranih sme&scaron;a kori&scaron;ćenjem tzv. testova<br />&bdquo;izluživanja&ldquo; kao i definisanje dominantnog mehanizma izluživanja koji<br />omogućava transport metala. Drugi deo istraživanja&nbsp; ima za cilj ispitivanje<br />mogućnosti primene nano nula valentnog gvožđa obloženog sa bentonitom,<br />kaolinitom i karboksimetilcelulozom za tretman zagađenog sedimenta na lokaciji<br />(in-situ), uz određivanje potencijalnog rizika po okolinu na osnovu rezultata<br />sekvencijlane ekstrakcione procedure i ekstrakcija&nbsp; u jednom koraku nakon<br />tretmana. Primenjeni su i modifikovani testovi izluživanja sa ciljem &scaron;to bolje<br />simulacije realnih uslova. Rezultati dobijeni simulacijom ovih uslova i daljom<br />karakterizacijom sme&scaron;a, kako sa nanomaterijalom tako i sme&scaron;a sa glinom,<br />omogućuju izradu modela pona&scaron;anja metala u smislu dugoročnog &quot;izluživanja&quot; iz<br />tretiranog (stabilizovanog) sedimenta kao i procenukoji materijali su efikasniji<br />za imobilizaciju toksičnih metala u sedimentu.</p> / <p>This thesis explores the possibility of using nano&nbsp; zero valent iron stabilized with<br />bentonite, kaolinite, and carboxymethyl cellulose for the immobilization of heavy<br />metals, as well as the behaviour and fate of metalsin sediments. Research is focused<br />in two directions: the first part of the study aimsto find a better understanding of the<br />behaviour of metals in sediments and to determine their potential mobility,<br />bioavailability and potential toxicity based on sequential extraction procedures and<br />acid volatile sulphides and simultaneously extracted metals methods, in untreated and<br />treated sediment samples. The efficacy of using nanomaterials for the immobilization<br />of metals in sediments is also determined, by applying &quot;leaching&quot; tests to the treated<br />mixtures and defining the dominant leaching mechanism that enables the transport of<br />metals. The second part of the study aims to examine the possibilities of applying<br />nano zero valent iron coated with bentonite, kaolinite and carboxymethyl cellulose for<br />the treatment of contaminated sediment in-situ, to&nbsp; determine the potential risk posed<br />to the environment after treatment, based on the results of sequential extraction<br />procedures and a single step extraction. Modified leaching tests were applied in order<br />to achieve better simulation of real conditions. The results of simulating these<br />conditions and further characterization of mixtureswith both nanomaterials and clay,<br />provide a long term &quot;leaching&quot; model for the behaviour of metals in the treated<br />(stabilized) sediments, as well as assessing which&nbsp; materials are most effective for the<br />immobilization of toxic metals in sediments.</p>

<p>Predmet&nbsp; izučavanja&nbsp; ove&nbsp; disertacije&nbsp; bio&nbsp; je&nbsp; ispitivanje&nbsp; mogućnosti&nbsp; kori&scaron;ćenja&nbsp; piritne&nbsp;izgoretine&nbsp; u&nbsp; tretmanu&nbsp; otpadnih&nbsp; voda&nbsp; tekstilne&nbsp; industrije&nbsp; kao&nbsp; i&nbsp; dalji&nbsp; tretman&nbsp; mulja&nbsp; nastalog&nbsp;nakon ovog procesa. Naime, nakon iskori&scaron;ćenja ovog otpada &nbsp;u Fenton procesima, iskori&scaron;ćena&nbsp;piritna izgoretina u najvećem procentu čini mulj koji zaostaje nakon tretmana. Kako se piritna&nbsp;ruda jo&scaron; u procesu proizvodnje sumporne kiseline&nbsp; koristi nepreči&scaron;ćena, zaostali&nbsp; mulj koji je&nbsp;potencijalno&nbsp; toksičan&nbsp; i&nbsp; ne&nbsp; može&nbsp; se&nbsp; direktno&nbsp; odlagati&nbsp; bez&nbsp; prethodnog&nbsp; tretmana.&nbsp; Stoga,&nbsp;primenjena&nbsp; je&nbsp; tehnika&nbsp; stabilizacija&nbsp; i&nbsp; solidifikacija&nbsp; (S/S)&nbsp; uz&nbsp; kori&scaron;ćenje&nbsp; portland&nbsp; cementa,&nbsp;kalcijum-oksida, prirodnog zeolita, letećeg pepela, kaolinita,&nbsp; bentonita i&nbsp; autohtone&nbsp; gline &nbsp;za&nbsp;imobilizaciju metala. Istraživanja u ovoj disertaciji vr&scaron;ena su u dve faze. Prva faza imala je za&nbsp;cilj&nbsp; optimizaciju&nbsp; operativnih&nbsp; uslova&nbsp; Fenton&nbsp; tretmana&nbsp; pri&nbsp; kojima&nbsp; se&nbsp; postiže&nbsp; najvi&scaron;i&nbsp; stepen&nbsp;obezbojavanja&nbsp; i&nbsp; mineralizacije&nbsp; ispitivanih&nbsp; efluenata.&nbsp; Takođe&nbsp; ispitivanje&nbsp; je&nbsp; uključilo&nbsp; i&nbsp;karakterizaciju nastalih efluenata kako bi se procenila efikasnost primenjenog, i mogućnost&nbsp;daljeg&nbsp; tretmana.&nbsp; Druga&nbsp; faza&nbsp; uključivala&nbsp; je&nbsp; karakterizaciju&nbsp; nastalog&nbsp; mulja&nbsp; nakon&nbsp; tretmana&nbsp;obojenih&nbsp; efluenata&nbsp; i&nbsp; njegov&nbsp; tretman&nbsp; solidifikacijom&nbsp; i&nbsp; stabilizacijom.&nbsp; Vr&scaron;eno&nbsp; je&nbsp; određivanje&nbsp;efikasnosti&nbsp; primenjenih&nbsp; imobilizacionih&nbsp; agenasa&nbsp; u&nbsp; S/S tretmanu&nbsp; i&nbsp; dominantnog&nbsp; mehanizma&nbsp;<br />izluživanja&nbsp; metala&nbsp; koji&nbsp; opisuju&nbsp; njihov&nbsp; transport&nbsp; iz&nbsp; dobijenih&nbsp; solidifikata.&nbsp; Primenjeni&nbsp; su&nbsp; i&nbsp;modifikovani&nbsp; testovi&nbsp; izluživanja&nbsp; sa&nbsp; ciljem&nbsp; &scaron;to&nbsp; bolje&nbsp; simulacije&nbsp; realnih&nbsp; uslova.&nbsp; Rezultati&nbsp;dobijeni&nbsp; simulacijom&nbsp; uslova&nbsp; će&nbsp; dalje&nbsp; omogućiti&nbsp; modelovanje&nbsp; pona&scaron;anja&nbsp; metala&nbsp; u&nbsp; smislu&nbsp;dugoročnog&nbsp; &quot;izluživanja&quot;&nbsp; iz&nbsp; tretiranog&nbsp; otpada&nbsp; kao&nbsp; i&nbsp; procenu&nbsp; najefikasnijih&nbsp; agenasa&nbsp; za&nbsp;imobilizaciju različitih metala u ovom tipu otpada. TakoĎe primenjeni su testovi izluživanja&nbsp;sa jednom ekstrakcijom kako bi se osiguralo&nbsp; slaganje rezultata sa maksimalno dozvoljenim&nbsp;koncentracijama&nbsp; aktuelnih&nbsp; pravilnika.&nbsp; Na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata&nbsp; zaključeno&nbsp; je&nbsp; da&nbsp; se&nbsp;piritna izgoretina može uspe&scaron;no koristiti kao izvor katalitičkog gvožđa u Fenton tretmanima&nbsp;obojenih&nbsp; efluenata&nbsp; i&nbsp; može&nbsp; se&nbsp; smatrati&nbsp; efektivnom&nbsp; metodom &nbsp; predtretmana&nbsp; za&nbsp;nebiodegradabilne&nbsp; otpadne&nbsp; vode,&nbsp; čineći&nbsp; ih&nbsp; pogodnijim&nbsp; za&nbsp; konvencionalni&nbsp; biolo&scaron;ki&nbsp; tretman.&nbsp;Takođe&nbsp; u&nbsp; drugoj&nbsp; fazi&nbsp; istraživanja,&nbsp; na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata,&nbsp; zaključeno&nbsp; je&nbsp; da&nbsp; je&nbsp; mulj&nbsp;tertian&nbsp; sa&nbsp; navedenim&nbsp; imobilizacionim&nbsp; agensima&nbsp; uspe&scaron;no&nbsp; solidifikovan&nbsp; i&nbsp; stabilizovan&nbsp;materijal.&nbsp; Optimalane&nbsp; su&nbsp; sme&scaron;e&nbsp; koje&nbsp; kao&nbsp; jedan&nbsp; od&nbsp; imobilizacionih&nbsp; agenasa&nbsp; sadrže&nbsp; leteći&nbsp;<br />pepeo, prevashodno u kombinaciji sa cementom i krečom. Dobijeni podaci su &nbsp;neprocenjivi sa&nbsp;aspekta ekonomski i ekolo&scaron;ki prihvatljivog upravljanja opasnim industrijskim otpadom.&nbsp;</p> / <p>This work is concerned with exploring the possibility of using pyrite cinders in the treatment&nbsp;of&nbsp; textile&nbsp; industry&nbsp; effluents&nbsp; and&nbsp; further&nbsp; treatment&nbsp; of&nbsp; sludge&nbsp; generated&nbsp; after&nbsp; this&nbsp; process.&nbsp;Namely,&nbsp; after&nbsp; the&nbsp; utilization&nbsp; of&nbsp; this&nbsp; waste&nbsp; in&nbsp; Fenton&nbsp; processes&nbsp; slag&nbsp; that&nbsp; remains&nbsp; after&nbsp;treatment is mostly composed of used pyrite cinder. As the pyrite ore, in the production of&nbsp;sulfuric&nbsp; acid,&nbsp; is&nbsp; used&nbsp; untreated,&nbsp; sludge&nbsp; that&nbsp; remains&nbsp; is&nbsp; potentially&nbsp; toxic&nbsp; and&nbsp; cannot&nbsp; be&nbsp;disposed&nbsp; directly&nbsp; without&nbsp; treatment.&nbsp; Therefore,&nbsp; the&nbsp; stabilization&nbsp; and&nbsp; solidification&nbsp; (S/S)&nbsp;technique&nbsp; with&nbsp; the&nbsp; usage&nbsp; of&nbsp; portland&nbsp; cement,&nbsp; calcium&nbsp; oxide,&nbsp; zeolite,&nbsp; fly&nbsp; ash,&nbsp; kaolinite,&nbsp;bentonite and native clay was used for metal immobilization. The research in this dissertation&nbsp;was carried out in two phases. The first phase aimed to optimize the operational conditions of&nbsp;Fenton&nbsp; treatment&nbsp; in&nbsp; which&nbsp; the&nbsp; highest&nbsp; degree&nbsp; of&nbsp; decolourization&nbsp; and&nbsp; mineralization&nbsp; was&nbsp;achieved in tested effluents. Also the research has included the characterization of generated&nbsp;effluents in order to evaluate the effectiveness of the treatment applied, and the possibility of&nbsp;further&nbsp; treatment.&nbsp; The&nbsp; second&nbsp; phase&nbsp; involved&nbsp; the&nbsp; characterization&nbsp; of&nbsp; the&nbsp; generated&nbsp; sludge&nbsp;after the treatment of effluents that contained dyes and its treatment with solidification and&nbsp;stabilization technique.&nbsp; The determination of used immobilization agents effectiveness was&nbsp;Conducted&nbsp; to&nbsp; determine&nbsp; the&nbsp; efficacy&nbsp; of&nbsp; immobilization&nbsp; agents&nbsp; in&nbsp; S&nbsp; /&nbsp; S&nbsp; treatment&nbsp; and&nbsp; the&nbsp;dominant&nbsp; mechanism&nbsp; of&nbsp; leaching&nbsp; of&nbsp; metals&nbsp; that&nbsp; describe&nbsp; their&nbsp; transport&nbsp; from&nbsp; the&nbsp; received&nbsp;solidificate . Were applied and modified leaching tests with the aim of better simulation of&nbsp;real&nbsp; conditions.&nbsp; The&nbsp; results&nbsp; obtained&nbsp; by&nbsp; condition&nbsp; simulation&nbsp; will&nbsp; enable&nbsp; the&nbsp; modeling&nbsp; of&nbsp;behavior of metals in terms of long-term leaching period from the treated sludge and assess&nbsp;the most effective agents for the immobilization of various metals in this type of waste. Also,&nbsp;single-extraction leaching tests were applied to ensure the accordance of obtained results &nbsp;with&nbsp;the maximum permissible concentrations of current regulations. Based on these results, it was&nbsp;concluded&nbsp; that&nbsp; the&nbsp; pyrite&nbsp; cinders&nbsp; can&nbsp; be&nbsp; successfully&nbsp; used&nbsp; as&nbsp; a&nbsp; source&nbsp; of&nbsp; catalytic&nbsp; iron&nbsp; in&nbsp;Fenton&nbsp; treatment&nbsp; of&nbsp; effluents&nbsp; containing&nbsp; dyes,&nbsp; and&nbsp; can&nbsp; be&nbsp; considered&nbsp; an&nbsp; effective&nbsp;pretreatment&nbsp; method&nbsp; for&nbsp; non-biodegradable&nbsp; waste&nbsp; waters,&nbsp; making&nbsp; them&nbsp; amenable&nbsp; to&nbsp;conventional biological treatment. Also in the second phase, based on the results obtained, it&nbsp;was concluded that the sludge treated with&nbsp; aforementioned&nbsp; immobilization agents represents&nbsp;a successfully solidified and stabilized material. The optimal mixtures are those that contain&nbsp;fly ash as one of the used immobilization agents, primarily in combination with cement and&nbsp;lime.&nbsp; The&nbsp; obtained&nbsp; data&nbsp; are&nbsp; invaluable&nbsp; in&nbsp; terms&nbsp; of&nbsp; economic&nbsp; and&nbsp; environmentally&nbsp; sound&nbsp;management of hazardous industrial waste.</p>

Ehemalige Urangruben tragen durch das anfallende Flutungswasser maßgeblich zur Ausbreitung von Schadstoffen wie Uran und Arsen in teils dicht besiedelte Gebiete bei. Um die Prozesse in den unterirdischen Gruben besser zu verstehen und alternative Strategien zur konventionellen, kostenintensiven Wasserbehandlung entwickeln zu können, war das Ziel der Arbeit, mikrobielle Gemeinschaften aus drei gefluteten Uranerzbergwerken in Sachsen, namens Pöhla, Schlema und Zobes, die unterschiedliche Flutungsstadien repräsentierten, zu charakterisieren und den mikrobiellen Einfluss auf die Mobilität von Uran und Arsen zu untersuchen. Um herauszufinden, welche Mikroorganismen die hydrochemischen Vorgänge im Untergrund der Uranerzbergwerke beeinflussen könnten, wurde die Diversität und Zusammensetzung mikrobieller Gemeinschaften mittels Pyrosequenzierung eines Fragments des 16S rRNA Gens (16S rDNA) und CARD-FISH ermittelt. Wenngleich Clusteranalysen zeigten, dass sich die planktonischen Gemeinschaften hinsichtlich ihrer bakteriellen Zusammensetzung zwischen den drei Uranerzbergwerken unterschieden, wurden alle von chemolithotrophen Schwefeloxidierern der Beta- und Epsilonproteobacteria dominiert, die mit den Gattungen Thiobacillus und Sulfuritalea bzw. Sulfuricurvum und Sulfurimonas vertreten waren. Im Unterschied zu den planktonischen Gemeinschaften bestanden in situ Biofilme, die auf BACTRAPs während einer 3-monatigen Exposition im Flutungswasser anwuchsen, laut Pyrosequenzierung zu einem wesentlichen, mitunter dominanten Anteil aus metall- bzw. sulfatreduzierenden Deltaproteobacteria. In Biofilmgemeinschaften aus Zobes wurden hauptsächlich Geobacter sp. detektiert, die als Fe(III)- und U(VI)-Reduzierer bekannt sind. Obwohl Archaea basierend auf den Ergebnissen der CARD-FISH-Analyse nur einen sehr geringen Anteil der planktonischen Gemeinschaften ausmachten, wurden mittels Pyrosequenzierung planktonische Euryarchaeota der Thermoprotei in allen Gruben detektiert. In planktonischen Gemeinschaften und 3-monatigen Biofilmen aus Pöhla und Zobes wurden zudem methanogene Crenarchaeota, vor allem Methanobacteria und teilweise Methanomicrobia, ermittelt. Die 16S rRNA-Analyse, die ergänzend zum DNA-basierten Ansatz durchgeführt wurde, lieferte Hinweise darauf, dass die detektierten, dominanten Mikroorganismen, Bacteria sowie Archaea, in der planktonischen Gemeinschaft aus Schlema und den Biofilmgemeinschaften stoffwechselaktiv waren. In der planktonischen Gemeinschaft aus Zobes wurden im Vergleich zur DNA-basierten Analyse höhere Abundanzen für Verrucomicrobia, Acidobacteria und Alphaproteobacteria ermittelt, deren Bedeutung offen bleibt. Untersuchungen zum mikrobiellen Stoffwechselpotential planktonischer Gemeinschaften mittels CFU- und MPN-Analysen ergaben, dass Mikroorganismen aus allen Urangruben ein breites Spektrum anaerober Reaktionen (Nitrat-, Eisen-, Mangan-, Arsenat- und Sulfatreduktion und Acetogenese) unter Laborbedingungen abdeckten. In guter Übereinstimmung mit den Sequenzierungsergebnissen konnten methanogene Mikroorganismen nur im Flutungswasser aus Pöhla und Zobes detektiert werden. Die Metaproteomanalyse ergab, dass 61,6% der Peptide in der planktonischen Gemeinschaft aus Schlema von den dominanten Epsilonproteobacteria stammten. Dagegen wurden für Zobes detektierte Peptide mehrheitlich methylotrophen und eisenoxidierenden Betaproteobacteria der Familien Methylophilaceae bzw. Gallionellaceae sowie methylotrophen Gammaproteobacteria der Methylococcaceae zugewiesen. Obwohl die Mehrheit der Proteine an der Translation beteiligt war, konnten insgesamt 49 Proteingruppen ermittelt werden, deren Vertreter für den mikrobiellen Energiestoffwechsel relevant waren. Insbesondere planktonische Gammaproteobacteria aus Zobes konnten so mit dem Kohlenstoff- und Schwefelkreislauf in Zusammenhang gebracht werden. Mithilfe von Labormikrokosmen wurde der potentielle Einfluss mikrobieller Gemeinschaften aus Schlema auf die Mobilität von Arsen und Uran im Flutungswasser mit Acetat als Elektronendonor unter anaeroben Bedingungen über einen Zeitraum von 98 Tagen untersucht. Im Vergleich zu den Kontrollen konnten sowohl die stimulierte, planktonische Gemeinschaft als auch Biofilme natürliches Arsen aus der wässrigen Phase fast vollständig entfernen. Allerdings wies der spätere Anstieg des gelösten Arsens daraufhin, dass der immobilisierte Zustand langfristig nicht stabil blieb. In stimulierten Biofilm-Ansätzen wurde Uran mit bis zu 39 ± 9% (in Anwesenheit von 7 µM natürlichem Uran) bzw. 34 ± 8% (bei Zugabe von 50 µM U(VI)) aus der wässrigen Phase langfristig (98 Tage) immobilisiert. Laserfluoreszenzspektroskopische Untersuchungen zeigten, dass Uran im Biofilm reduziert wurde.

Effective vascularization is crucial for almost any therapeutic tissue engineering concept. In this context, therapeutic angiogenesis attempts to enforce the natural process of blood vessel formation by provision of bioactive effectors. Along these lines, the aim of this work was to evaluate the potential of a modular hydrogel composed of the synthetic star-shaped poly(ethylene glycol) (starPEG) and the naturally occurring biopolymer heparin for the defined and orchestrated delivery of two major angiogenic growth factors, fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF). While starPEG determines the structural properties of the gel materials, effective administration of both cytokines is based on their natural affinity to heparin, the highly charged polysaccharidic building block capable of reversibly binding various growth factors upon geometrically matching electrostatic interactions. Varying the molar ratio of starPEG to heparin upon network formation, different hydrogel types with distinct mechanical characteristics but constant heparin content could be produced. As heparin represents the basis for the growth factor interaction with the scaffolds, the matrices were found to bind and release FGF-2 or VEGF independently of the particular network stiffness and structural properties of the different gel types. Moreover, the material could be utilized for a modular delivery of growth factor combinations over a broad range of concentrations. To evaluate the general suitability for pro-angiogenic stimulation, the provision of FGF-2 and VEGF from starPEG-heparin hydrogels differing in their mechanical characteristics and biofunctionalization with adhesive peptides was studied using human endothelial cells, the cell type that forms the inner layer of any blood vessel. Results showed that the presence of the adhesion ligand was an essential requirement to mediate cell attachment and subsequent growth on the scaffolds. Apart from that, hydrogels with an intermediate stiffness showed beneficial effects on endothelial cell proliferation/survival while in parallel also the differentiation into elongated, pro-tubular structures could be promoted. While the delivery of FGF-2 was able to enhance cell growth, VEGF mainly initiated endothelial cell shape elongation. However, with a parallel administration of both growth factors, their beneficial effects could be combined to obtain high numbers of endothelial cells undergoing differentiation. Furthermore, besides the possibility of growing endothelial cells on top of the biofunctionalized hydrogels, the release of growth factors by starPEG-heparin matrices could be applied as a stimulus to attract the cells to migrate into the direction of the scaffolds. While FGF-2 and VEGF supported cell motility to a similar extent, their combined action was found to exert the strongest effect on endothelial cell migration. Based on the results of these in vitro experiments, matrices most effectively stimulating pro-angiogenic cellular responses were selected for in vivo studies applying the functionalized materials to the chorioallantoic membrane (CAM) of fertilized chicken eggs, an assay commonly used to evaluate the vascularization potential of biomaterials. In this assay, the delivery of FGF-2 and/or VEGF by starPEG-heparin hydrogels induced a substantial angiogenic response within the CAM system, while the combination of both growth factors tends to increase vascularization most effectively. In order to adjust the starPEG-heparin hydrogel system to the complex requirements of therapeutic angiogenesis, further options to specifically modulate the FGF-2 or VEGF release were explored. With the incorporation of enzymatically cleavable peptide linkers, not only the possibility for a cellular remodeling of the gel matrix could be permitted, but also the growth factor release was substantially enhanced upon network degradation. Moreover, with the gradual removal of FGF-2 and VEGF interaction sites from heparin upon selective desulfation, the binding of both growth factors to hydrogels composed out of starPEG and desulfated heparin was significantly reduced depending on the remaining sulfate content. Irrespective of the lower immobilized amounts of FGF-2 or VEGF, higher absolute quantities of both growth factors could be released and retained in the medium due to their decreased affinity to heparin, thereby enhancing the delivery efficiency of the scaffolds. Going beyond common concepts for triggered cytokine release, hydrogel-bound FGF-2 or VEGF could be effectively displaced from their heparin binding sites by an application of the competitive, highly-heparin affine molecule chitosan. As chitosan could be introduced at different time points, not only the amounts of delivered growth factor were enhanced, but also the FGF-2 or VEGF release kinetics could be specifically modulated. Taken together, starPEG-heparin hydrogels with independently adaptable physical and biomolecular composition were demonstrated to provide time-resolved multi-factor delivery of pro-angiogenic growth factors resulting in valuable new options for therapeutic angiogenesis.

This licentiate thesis is focused on two methods for protein immobilization to biosensor surfaces for future applications in protein microarray formats. The common denominator is a surface chemistry based on a gold substrate with a self-assembled monolayer (SAM) of functionalized alkanethiolates. Both methods involve photochemistry, in the first case for direct immobilization of proteins to the surface, in the other for grafting a hydrogel, which is then used for protein immobilization. Paper I describes the development and characterization of Chelation Assisted Photoimmobilization (CAP), a three-component surface chemistry that allows for covalent attachment and controlled orientation of the immobilized recognition molecule (ligand) and thereby provides a robust sensor surface for detection of analyte in solution. The concept was demonstrated using His-tagged IgG-Fc as the ligand and protein A as the analyte. Surprisingly, as concluded from IR spectroscopy and surface plasmon resonance (SPR) analysis, the binding ability of this bivalent ligand was found to be more than two times higher with random orientation obtained by amine coupling than with homogeneous orientation obtained by CAP. It is suggested that a multivalent ligand is less sensitive to orientation effects than a monovalent ligand and that island formation of the alkanethiolates used for CAP results in a locally high ligand density and steric hindrance. Paper II describes the development of nanoscale hydrogel structures. These were photografted on a SAM pattern obtained by dip-pen nanolithography (DPN) and subsequent backfilling. The hydrogel grew fast on the hydrophilic patterns and slower on the hydrophobic background, which contained a buried oligo(ethylene glycol) (OEG) chain. Using IR spectroscopy, it was found that the OEG part was degraded during UV light irradiation and acted as a sacrificial layer. In this process other OEG residues were exposed and acted as new starting points for the self-initiated photografting and photopolymerization (SIPGP). A biotin derivative was immobilized to the hydrogel density pattern and interaction with streptavidin was demonstrated by epifluorescence microscopy.

No description available.

Technetium is the lightest element whose isotopes are all radioactive. Among them, 99Tc (hereafter simply referred as technetium or Tc) is the most abundant and raises great environmental concern due to its relatively long half-life of 2.14×105 years and the high mobility of pertechnetate, Tc(VII)O4, its most stable form under aerobic conditions. The reduction from Tc(VII) to Tc(IV) is one of the most successful strategies for Tc immobilization; however, the mechanism of this redox reaction is not yet fully understood. This presents a large gap in the general knowledge of technetium chemistry and a significant obstacle for the modeling of its reactivity in contexts like a nuclear waste repository. This thesis was developed in the frame of the BMWi funded VESPA II project, and it studies the surface-mediated reduction of 99Tc(VII) using a combination of fundamental chemistry and its application for remediation and nuclear waste management. First, spectro-electrochemical methods (cyclic voltammetry, rotating disk electrode, chronoamperometry coupled with UV-vis, Raman microscopy and nuclear magnetic resonance) were employed to study the reduction mechanism of 0.5 mM KTcO4 in non-complexing media (2 M NaClO4) in the pH range from 2.0 to 10.0. It was found that the mechanism depends on the pH. At pH 2.0 it splits into two steps: Tc(VII) gains 2.1 ± 0.3 electrons and becomes Tc(V) that rapidly reduces to Tc(IV) with the transfer of further 1.3 ± 0.3 electrons. In contrast, at pH ≥ 4.0 there is a direct transfer of 3.2 ± 0.3 electrons. The complete reduction of Tc(VII) yielded a black solid that was successfully characterized by NMR and Raman microscopy as Tc(IV) regardless of the initial pH at which the reaction occurred. Unfortunately, it was not possible to observe the Tc(V) species at pH 2.0 by the spectroscopic tools used. Second, the reductive immobilization of Tc(VII) by pure pyrite and a synthetic mixture marcasite-pyrite 60:40 (synthetic FeS2, with both minerals being polymorphs) was studied by a combination of batch sorption experiments (Tc-removal was studied varying pH, contact time, ionic strength and Tc concentration) and several spectroscopies and microscopies such as Raman microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and VIII X-ray absorption spectroscopy. It was found that both pyrite and the synthetic FeS2 promote the reduction of Tc(VII) to Tc(IV). In the case of pure pyrite, the Tc-removal is complete after one day in contact at pH ≥ 5.5. The spectroscopic analysis showed at pH 6.0 an inner-sphere complex between Tc(IV) dimers and hematite formed as secondary mineral on the pyrite surface. In contrast, at pH 10.0 Tc(IV) gets incorporated into surficial magnetite by replacing Fe3+ in octahedral position, with Fe2+ providing reasonable charge compensation for Tc4+. The presence of marcasite made the process slower and less efficient since the synthetic FeS2 was capable to remove 100% Tc from solution only after seven days in contact at 6.0 < pH ≤ 9.0 while the Tc-removal at pH 10.0 was only around 80%. At pH 6.0 the formation of hematite was also observed, suggesting that the formed Tc(IV) species at the surface is the same as with pure pyrite. However, at pH 10.0 the formation of sulfate minerals evidences a change of redox active species: S2- instead of Fe2+. This, combined with the fact that in both solids the formation of TcSx species was detected by XPS at pH 10.0, shows the potential of sulfur as another reducing agent for Tc(VII). The effect of polymorphism on the Tc removal is remarkable and this work shows the relevance of more studies on the interaction of radionuclei with other mineral polymorphs. Regardless of the kinetics of the Tc removal, both pyrite and synthetic FeS2 hindered the re-oxidation of Tc(IV) when exposed to ambient atmosphere for two months. This feature makes them good candidates for the remediation of technetium from contaminated waters. Moreover, natural attenuation effects can be expected for technetium in the near and far field of nuclear waste repositories wherever iron sulfide is present. The results presented in this work contribute to a better understanding of the fundamental aqueous chemistry of technetium and confirm pyrite, a ubiquitous mineral, as a very good candidate for technetium scavenging even in the presence of marcasite. These results close important gaps in thermodynamic databases that are needed for the safety assessment, i.e. modeling of fission products.