Liver cancer accounts for nearly 10% of all cancers in the US. Intrahepatic Arterial Radiomicrosphere Therapy (RMT), also known as Selective Internal Radiation Treatment (SIRT), is one of the evolving treatment modalities. Successful patient clinical outcomes require suitable treatment planning followed by delivery of the microspheres for therapy. The production and in vitro evaluation of various polymers (PGCD, CHS and CHSg) microspheres for a RMT and RMT planning are described. Microparticles with a 30±10 µm size distribution were prepared by emulsion method. The in vitro half-life of the particles was determined in PBS buffer and porcine plasma and their potential application (treatment or treatment planning) established. Further, the fast degrading microspheres (≤ 48 hours in vitro half-life) were labeled with 68Ga and/or 99mTc as they are suitable for the imaging component of treatment planning, which is the primary emphasis of this dissertation. Labeling kinetics demonstrated that 68Ga-PGCD, 68Ga-CHSg and 68Ga-NOTA-CHSg can be labeled with more than 95% yield in 15 minutes; 99mTc-PGCD and 99mTc-CHSg can also be labeled with high yield within 15-30 minutes. In vitro stability after four hours was more than 90% in saline and PBS buffer for all of them. Experiments in reconstituted hemoglobin lysate were also performed. Two successful imaging (RMT planning) agents were found: 99mTc-CHSg and 68Ga-NOTA-CHSg. For the 99mTc-PGCD a successful perfusion image was obtained after 10 minutes, however the in vivo degradation was very fast (half-life), releasing the 99mTc from the lungs. Slow degrading CHS microparticles (> 21 days half-life) were modified with p-SCN-b-DOTA and labeled with 90Y for production of 90Y-DOTA-CHS. Radiochemical purity was evaluated in vitro and in vivo showing more than 90% stability after 72 and 24 hours respectively. All agents were compared to their respective gold standards (99mTc-MAA for 68Ga-NOTA-CHSg and 99mTc-CHSg; 90Y-SirTEX for 90Y-DOTA-CHS) showing superior in vivo stability. RMT and RMT planning agents (Therapy, PET and SPECT imaging) were designed and successfully evaluated in vitro and in vivo.

L'encapsulation de protéines pose de nombreuses difficultés liées à leurs propriétés physicochimiques, leur sensibilité aux conditions environnementales et opératoires. La structure 3D spécifique de chaque protéine étant directement liée à son activité biologique, un contrôle de l'intégrité protéique est indispensable pour assurer l'efficacité et la sécurité des systèmes formulés. Dans cet optique, l'encapsulation par émulsion multiple a été appliquée à une protéine modèle : la myoglobine (Mb). Le but de cette thèse a été l'étude du procédé d'encapsulation à travers 3 objectifs. Le premier fut d'étudier l'influence de paramètres de formulation sur les propriétés des particules obtenues et sur la conformation de la Mb. Les mesures en spectrométrie UV/Vis. et le calcul des principaux rapports d'absorbance ont constitué une méthode de contrôle fiable et rapide. Le second fut de valider la pertinence et de montrer les limites de cette méthode en la comparant à une seconde méthode utilisant des mesures conductimétriques. Enfin, l'étape de solidification des particules par élimination du solvant ainsi que le changement de solvant ont été étudiés.. Des microsphères creuses de 15μm avec un rendement d'encapsulation de 36% ont pu être obtenues tout en maintenant la conformation native de la Mb. L'emploi de polymère de masse moléculaire élevée et un taux d'élimination de solvant trop rapide sont 2 paramètres altérants significativement la protéine. Ces travaux ouvrent la voie au développement de transporteurs d'O2 utilisables par exemple dans le cas de pathologies musculaires / Protein encapsulation results in several problems related to their physicochemical properties, their sensitivity to environmental conditions and operating procedures. The specific 3D structure being directly linked to their biological activity, monitoring of protein integrity is crucial to ensure the efficacy and security of formulations. In this context, the multiple emulsion method was applied to a model protein: myoglobin (Mb). The aim of this thesis was to study the encapsulation process through 3 objectives. The first was to study the influence of formulation parameters on the particle properties and the conformation of Mb. Measurements by UV/Vis. spectrometry and calculation of key absorbance ratios established a reliable and rapid method for protein monitoring. The second was to validate the pertinence and show the limits of this method by comparing it to a second one using conductimetry measurements. Finally, the particle solidification by solvent removal and the solvent exchange were studied. The process maintains the Mb native conformation in Hollow microspheres of 15μm in diameter and an encapsulation efficiency of 36% were obtained, while keeping intact the Mb native conformation. The use of high molecular weight polymer and a fast solvent removal rate are 2 parameters inducing significant protein alteration. This work paves the way for the development of O2 carriers for muscular diseases for example

O processo de micrencapsulação de proteínas em microesferas (MS) de PLGA [poli (ácido lactico-co-glicolico)] é fácil de fazer e é uma ferramenta útil para melhorar tanto uma formulação quanto para aumentar a atividade imunológica de vacinas de novas gerações. A MS-PLGA têm caráter adjuvante porque é um sistema particulado e, além disto, controla a liberação do antígeno. O escopo desta tese foi o de dar uma nova roupagem para um antígeno vacinal tradicional e muito bem estudado- o toxoide diftérico (Dtxd). Estudaram-se a produção de MS de tamanho desejado; os mecanismos que controlam danos nas proteínas durante o processo de micrencapsulação; a produção de microesferas com características de liberações em tempos distintos e ensaios biológicos. O tamanho de MS é um determinante fundamental para controlar a velocidade de liberação de um soluto. Para se produzir MS com tamanhos controlados usou-se um desenho fatorial experimental com três fatores distintos e três pontos centrais, para se determinar a influência das variáveis (concentração de poli álcool vinílico; velocidade de agitação e relação fase dispersa/fase contínua) na determinação do tamanho das MS. Foram obtidas MS esféricas e lisas de 4- 15 µm de diâmetro. Estes resultados abrem a possibilidade de se formular PLGA-MS com tamanhos planejados através de um mínimo de experimentos. O mecanismo de danos conformacionais nas proteínas nas várias fases do processo de produção de PLGA-MS é ainda uma questão em aberto. Usaram-se várias técnicas biofísicas (HPLC, espectroscopias no uv, fluorescência e CD) além de ELISA para se testar a interferência dos sais da série de Hofmeister sobre a solubilidade e estabilidade da proteína durante a emulsificação e do contacto com a interface água/cloreto de metileno (primeira etapa do processo de preparação de MS). Estudaram-se também a influência de oligômeros de PLGA e SDS sobre a estrutura da proteína no meio de liberação (etapa de liberação do soluto). A emulsificação de Dtxd na presença de Mg2+ induziu agregação protéica, com exposição de resíduos hidrofóbicos para o meio; variações no ângulo diédrico do S-S proteico e perda de identidade imunológica. Esta agregação foi quase abolida pelo caotrópico SCN- (toxicidade = 30 g/ homem adulto de 70 kg). A conformação \"nativa\" do Dtxd e sua atividade biológica foram protegidas pelo KSCN. Os oligômeros de PLGA e o SDS induziram uma conformação de Dtxd nova. A adição de KSCN na fase aquosa aumentou a eficiência de encapsulação de Dtxd pela PLGA-MS em 20 %. Esta foi a solução mais simples quando comparada com aquelas descritas na literatura. Produziram-se seis formulações diferentes (diferentes massas molares e carboximetilações do PLGA) com pelo menos três cinéticas de liberações distintas. Imunizaram-se camundongos com 5 µg de Dtxd encapsulado em MS-PLGA usando-se dois polímeros de 12 kDa (-COOH livre ou metilado) e um outro de 63 kDa (metilado). O padrão de resposta e a maturidade imunológicas foram medidos por titulações de IgG1 e IgG2a. Mantiveram-se os mesmos padrões de resposta humoral (desejável). Menores quantidades de antígenos foram necessárias para se obter os mesmos benefícios gerados pela vacina tradicional de Dtxd. Aumentaram-se a produção e a seletividade de anticorpos através de duas manipulações simples: a formulação e o tempo da aplicação da dose de reforço. Estes resultados colocam estas formulações na área de vacinas de sucesso uma vez que também foram obtidas memórias imunológicas. / The protein microencapsulation within microspheres (MS) of PLGA (Poly-lactide-co-glycolide) is easy to do and, it is a useful tool to enhance formulation and immunologic performances for new generation vaccines. MS-PLGA has adjuvant character because it is a particulate system and can control the antigen release. The question addressed in this thesis was to give this new dress for the traditional and well studied vaccine antigen - the diphtheria toxoid (Dtxd). The steps of MS control size production; mechanism to control protein damages; MS production with different polymers and biological assay were addressed here. MS size is a primary determinant of solute release velocity. A full factorial experimental design 23 with triplicate at the central point was used to determine the influence of variables (polyvinyl alcohol concentration, stirring velocity and the relationship between dispersed /continuous phase) on MS size. Uniformly spherical and smooth microspheres (4 - 15 µm of diameter) were obtained. These results open the possibility of formulating PLGA microspheres with custom sizes performing a minimum of experiments as required for specific applications. It stills an open question to detail the conformational mechanism of protein damages during the various steps of the PLGA microencapsulation process. Various techniques (HPLC gel filtration, ELISA, Fluorescence, UV and Circular dichroism spectroscopies) were tested on the interference of the Hofmeister ion series over protein solubility and stability during the emulsification and contact with the interface water/CH2Cl2 interface (First step on MS preparation). The interference of SDS and PLGA olygomers over protein structure in the liberation media was also studied (solute liberation step). The Dtxd emulsification in the presence of Mg2+ was followed by protein aggregation, with exposition of hydrophobic residues and changes on the dihedral S-S protein angle and loses on immunological identity. This aggregation is 95% avoided by the chaotropic and little toxic salt KSCN (30g/ adult human of 70 kg). All the \"native\" Dtxd conformation and biological properties were maintained by KSCN. MS with different liberation kinetics profile and different erosion characteristics were obtained by using six different polymers. The SDS and PLGA olygomers exerted a generation of new Dtxd molecular organization. The KSCN increased Dtxd encapsulation within PLGA-MS in more than 20 %. This was the simplest solution used to solve protein aggregation compared with others solutions used in the literature. The six different formulations produced (differing in molar mass and carboxymethylation) produced, at least, three different Dtxd liberation profiles. Mice were primed with 5 µg of Dtxd microencapsulated within MS prepared with 12 kDa (ended carboxymethylated or free PLGA) and with 63 kDa (methylated) PLGA. The response patterns and the immune maturity were measured by IgG1 and IgG2a titrations. The humoral pattern was maintained, but fewer antigens were needed to obtain the same traditional Dtxd vaccine benefits. The simple change on Dtxd-PLGA formulation and timing of the booster enhanced both, antibody production and selectivity. An immunological memory was also obtained, putting so, these formulations in the field of successful vaccine.

Probiotic lactic acid bacteria of genus Lactobacillus play an important role in the digestive tract of human. They are used in food processing and they are the part of food supplements. Lactic acid bacteria of the genus Lactobacillus can be identificated by polymerase chain reaction (PCR). Bacterial DNA was isolated from cell lysates of 4 synbiotic food suplements by magnetic particles P(HEMA-co-GMA). Isolated DNA was amplified by genus-specific and species-specific primers. Magnetic particles with immobilized antibodies against Lactobacillus bacteria were used in the next part of thesis. These particles were used for isolation target cells from products with their identification by genus specific PCR.

Extraction of nucleic acids is an important step for all molecular biological studies. The process of isolation of plant DNA is complicated due to the presence of polyphenols, polysaccharides and other metabolites. They can be co-isolated with DNA and act as PCR inhibitors. The aim of this study was to compare CTAB extraction procedure, Qiagen DNA easy kit, direct homogenization, carboxyl-functionalised magnetic non-porous HEMA based microspheres and combination of the above mentioned methods for DNA isolation from different plants. The DNA was evaluated regarding concentration, purity and amplification in PCR. All methods provided DNA that could be used in downstream PCR applications. However, there were differences regarding yield, purity, labour intensiveness and cost. Combination of direct homogenization and magnetic microspheres coated by carboxyl groups was isolated DNA from various plants and plant foods in a quality suitable for convectional PCR, real time PCR and restriction analysis. This method is fast, simple and does not require work with harmful substances.

ABSTRACT<p><p>This project aimed at developing a drug delivery system (DDS) able to enhance the stability and<p>residence time in vivo of antibodies (Abs). The system will deliver drug by the subcutaneous<p>route (SC), while ensuring accurate control of the drug release and the resulting plasmatic level. This technology platform will allow to reduce frequency of injection, potentially decrease side effects and maintain high concentration of Abs which will improve life of patient having chronic disease such as autoimmune and inflammatory disease. Biodegradable synthetic polymer-based formulations (polylactide-co-glycolide (PLGA)) were selected as carriers for encapsulated Abs. This was because they offer good protection for the Abs and allow sustained release of the Abs for a controlled period of time. After the evaluation of different encapsulation methods such as the water-oil-in-water (w/o/w) and the solid-in-oil-inwater<p>(s/o/w) processes, the encapsulation of the Ab in solid state (s/o/w) appeared to be more appropriate for producing Ab-loaded PLGA microspheres (MS). It allowed us to maintain the<p>Ab in a monomeric conformation and to avoid the formation of unsoluble aggregates mainly present at the water/oil interface. The first part of the project was the optimization of both the method for producing the Ab solid particles (spray-drying process) and the encapsulation of these Ab solid particles into the polymeric MS (s/o/w process) by design of experiment (DoE). These optimizations were carried out using a bovine polyclonal immunoglobulin G (IgG) as model molecule. In further optimization of the spray-drying process by (DoE), aqueous Ab solutions were spray-dried using a mini Spray-Dryer assembly with a 0.7 mm spray nozzle. In accordance with the particle size (d(0.5) ~5 μm), the stability (no loss of monomer measured by<p>size exclusion chromatography (SEC) and the yield of the spray-drying process (> 60 % w/w), the process parameters were set of follow: 3 mL/min as liquid feed flow rate, 130°C /75°C as inlet temperature (inlet T°) / outlet temperature (outlet T°), 800 L/h as atomization flow rate and<p>30 m3/h as drying air flow rate. For the s/o/w, the methylene chloride (MC) commonly used for<p>an encapsulation process was replaced by ethyl acetate (EtAc), which was considered as a more<p>suitable organic solvent in terms of both environmental and human safety. The effects of several processes and formulation factors were evaluated on IgG:PLGA MS properties such as: particle size distribution, drug loading, IgG stability, and encapsulation efficiency (EE%). Several formulations and processing parameters were also statistically identified as critical to get reproducible process (e.g. the PLGA concentration, the volume of the external phase, the emulsification rate, and the quantity of IgG microparticles). The optimized encapsulation<p>method of the IgG has shown a drug loading of up to 6 % (w/w) and an encapsulation efficiency<p>of up to 60 % (w/w) while preserving the integrity of the encapsulated antibody. The produced MS were characterized by a d(0.9) lower than 110 μm and showed burst effect lower than 50 %(w/w). In the second part of the project, the optimized spray-drying and s/o/w processes<p>developed with the IgG were applied to a humanized anti-tumor necrosis factor (TNF) alpha<p>MAb to confirm the preservation of the MAb activity during these processes. The selected s/o/w method allowed us to produce MAb-loaded PLGA MS with an appropriate release profile up to 6 weeks and MAb stability. In order to maintain the Abs’ activity, both during encapsulation and<p>dissolution, the addition of a stabilizer such as trehalose appeared to be crucial, as did the<p>selection of the PLGA. It was demonstrated that the use of a PLGA characterized by a 75:25<p>lactide:glycolide (e.g. Resomer ® RG755S) ratio decreased the formation of low molecular weight species during dissolution, which led to preserve Abs activity through its release from the<p>delivery system. Furthermore, the release profile was adjusted according to the type of polymer<p>and its concentration. E.g. 10 % w/v RG755S allowed Ab MS with a release time of 6 weeks to<p>be obtained. The optimization of both the formulation and the encapsulation process allowed<p>maximum 13 % w/w Ab-loaded MS to be produced. It was demonstrated that the Ab-loaded PLGA MS were stable when stored at 5°C for up to 12 weeks and that the selection of the appropriate type of PLGA was critical to assuring the stability of the system. The better stability observed when using a PLGA characterized by a 75:25 lactide:glycolide ratio was attributed to<p>its slower degradation rate. Finally, the sustained release of Ab from the developed MS and the preservation of its activity was confirmed in vivo in a pharmacokinetic (pK) study realized in<p>rats. In conclusion, the application of the concept of entrapment into a polymer matrix for<p>stabilization and sustained release of biological compounds was demonstrated through this work.<p><p><p><p>RÉSUMÉ<p><p>Ce projet a pour but de développer un système de délivrance de médicament capable d’augmenter la stabilité et le temps de résidence in vivo des anticorps. Ce système sera administré par voie sous-cutanée et permettra un control précis de la libération du produit et de son niveau plasmatique. Cette plateforme technologique nous permettra de réduire la fréquence d’injection, de réduire potentiellement les effets secondaires et de maintenir des concentrations élevées en anticorps tout en améliorant la vie des patients atteints de maladies chroniques autoimmunes ou inflammatoires. Les formulations à base de polymères synthétiques, biodégradables (PLGA) ont été sélectionnés comme véhicules pour encapsuler les anticorps. Ils offrent en effet une bonne protection pour les anticorps and permettent une libération contrôlée de ceux-ci pendant une période définie. Après l’évaluation de différents méthodes d’encapsulation tels que les procédés d’eau-dans-huile-dans-eau (w/o/w) et solide-dans-huile-dans-eau (s/o/w), l’encapsulation des anticorps sous forme solide apparaissait plus apporpriée pour produire des microsphères de polymère chargées en anticorps. Cette technique nous permettait de maintenir l’anticorps sous sa forme monomérique et d’éviter la formation d’agrégats insolubles qui apparaissaient principalement à l’interface eau/huile. La première partie du projet a été d’optimiser à la fois la méthode nous permettant d’obtenir les anticorps sous forme de particules solides (spray-drying) et la méthode d’encapsulation de ces particules d’anticorps dans les microsphères de polymères. Cela a été réalisé par des plans d’expérience en utilisant une IgG bovine polyclonale comme molécule modèle. Durant l’optimisation du procédé de spray-drying,<p>les solutions aqueuses d’anticorps ont été atomisées en utilisant le mini Spray-Dryer assemblé avec une buse de pulvérisation d’un diamètre de 0.7 mm. En accord avec la taille particulaire (d(0.5) ~5 μm), la stabilité (absence de perte en monomère mesurée par chromatographie d’exclusion de taille et le rendement d’atomisation (> 60 % w/w), les paramètres d’atomisation ont été fixés: 3 mL/min pour le débit de liquide, 130°C /75°C pour la température d’entrée / température de sortie, 800 L/h pour le débit d’air d’atomisation et 30 m3/h pour le débit d’air de séchage. Pour le s/o/w, le dichlorométhane communément utilisé dans les procédés d’encapsulation a été remplacé par l’acétate d’éthyle qui est considéré comme un meilleure solvant organique en terme d’environnement et de sécurité. Les effets de plusieurs paramètres de fabrication ou de formulation ont été évalués sur les propriétés des microsphères polymériques d’anticorps (distribution de taille particulaire, taux de charge en anticorps, stabilité de l’anticorps et efficacité d’encapsulation). Plusieurs paramètres de fabrication et de formulation ont été statistiquement identifiés comme critiques pour obtenir un procédé reproductible (par exemple. La concentration en PLGA, le volume de phase externe, la vitesse d’émulsification et la quantité d’anticorps). La méthode d’encapsulation ainsi optimisée permettait d’obtenir un taux<p>de charge jusqu’à 6% (w/w) avec une efficacité d’encapsulation jusqu’à 60 % (w/w) tout en<p>préservant l’intégrité de l’anticorps encapsulé. Les microsphères produites étaient caractérisées<p>par un d(0.9) inférieur à 110 μm et montraient une libération après 24 h inférieure à 50 % (w/w).<p>Dans le seconde partie du projet, les procédés d’atomisation et d’encapsulation développés avec<p>l’IgG ont été appliqués à un anticorps monoclonal anti-TNF alpha humanisé pour confirmer la<p>conservation de l’activité de l’anticorps pendant ces procédés. La méthode s/o/w sélectionnée<p>permettait de produire des microsphères de PLGA chargées en anticorps avec un profil de libération jusqu’à 6 semaines et un maintien de la stabilité de l’actif. Afin de maintenir l’activité de l’anticorps, à la fois pendant le procédé d’encapsulation et pendant la libération, l’ajout d’un stabilisant tel que le tréhalose est apparu crucial ainsi que le choix du type de PLGA. Il a été démontré que l’utilisation du PLGA caractérisé par un ratio lactide :glycolide de 75 :25 (par exemple, Resomer ® RG755S) diminuait la formation d’espèces de faible poids moléculaire<p>pendant la dissolution. Cela contribuait à préserver l’activité de l’anticorps durant la libération à partir des microsphères. De plus, le profil de libération était modulé en fonction du type de polymère et de sa concentration. Par exemple, l’utilisation d’une solution à 10 % w/v RG755S conduisait à la production de microsphères d’anticorps avec un temps de libération sur 6<p>semaines. L’optimisation de la formulation et du procédé d’encapsulation a permis de produire<p>des microsphères avec des taux de charge en anticorps de maximum 13 % w/w. Il a été démontré<p>que ces microsphères, stockées à 5°C, étaient stables jusqu’à 12 semaines et que la sélection du<p>type de PLGA était critique pour assurer la stabilité du système. La meilleure stabilité a été<p>obtenue en utilisant le PLGA caractérisé par un ratio lactide :glycolide de 75 :25. Cela a été<p>attribué à sa plus faible vitesse de dégradation. Enfin, la libération contrôlée de l’anticorps à<p>partir de ces microsphères et la conservation de son activité ont été confirmées in vivo lors d’une<p>étude pharmacocinétique réalisée chez le rat. En conclusion, ce travail a permis de démontrer<p>l’application du concept d’ « emprisonnement » des composés biologiques dans des matrices<p>polymériques afin de les stabiliser et contrôler leur libération. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

Les mousses syntactiques créées par l’association d’une matrice élastomère et de microsphères à paroi souple possèdent des propriétés acoustiques amortissantes intéressantes. Elles ouvrent de nouvelles perspectives dans la fabrication de sous-marins furtifs ou de navires, mais le principal frein à l’industrialisation de ces mousses est leur compressibilité : à haute profondeur, les mousses écrasées perdent leurs propriétés amortissantes. Nous nous intéressons donc à l’étude du renforcement de mousses syntactiques à matrice polyuréthanes. La littérature scientifique étant peu abondante sur ce sujet, une mousse syntactique modèle a été synthétisée en laboratoire pour permettre une meilleure caractérisation de ce matériau et de ses composants. En particulier, un moyen innovant de compression hydrostatique a été mis au point pour caractériser le comportement sous pression des microsphères et de la mousse. Les paramètres matériaux recueillis ont permis d’utiliser un modèle de la littérature qui a simulé l’influence de divers paramètres sur la compression de mousses syntactiques. Ce modèle a également pu prévoir les caractéristiques des composants d’une mousse dont la compressibilité répondrait à un cahier des charges préétabli. Ces différentes analyses ont démontré que le principal paramètre régissant la compression de mousses syntactiques est le module d’Young de la matrice. De plus, un renforcement en compression n’est obtenu qu’avec un renforcement chimique de la matrice ; la présence de charges (fibres, nanotubes de carbone) n’apporte pas de changements significatifs / Syntactic foams synthesized from an elastomeric matrix and soft-shell microspheres have shown interesting acoustical properties. They open new perspectives for the manufacturing of stealthy submarines or ships, but the industrialization of such material is held back by their great compressibility: hydrostatic pressure tends to crush the microspheres, which leads to a loss of the damping properties. We are therefore interested in studying the reinforcement of syntactic foams with polyurethane matrix. Scientific literature being scarce on this subject, a reference syntactic foam has been synthesized in the laboratory to allow a better characterization of this material and its components. In particular, an innovative test of hydrostatic compression has been developed to characterize the behavior under pressure of the microspheres and foam. A model of the literature simulating the compression of syntactic foams has been used thanks to the material parameters collected; it allowed us to test the influence of various parameters on this compression. This model could also predict the characteristics of the components of a foam whose compressibility would meet a set of specifications. These different analyses have shown that the main parameter governing the compression of syntactic foams is the Young's modulus of the matrix. In addition, a compression reinforcement can only be obtained using a chemical reinforcement of the matrix; the presence of fillers (fibers, MWCNTs) does not bring significant changes

The work deals with the possibilities of lightening of the flooring system. Flooring system is solved by lightening the material. The surface layer is modified by lightweight fillers made from the waste materials, lightweight waste materials and fillers made from natural substances. Simultaneously is this work dealing with options of lightening the surface layer by microspheric fillers of separated waste fly ash.

Treatment of wastewater using magnetic technology is a rising field. In this thesis, the latest research on the subject is reviewed and several adsorbents with different coatings, which impart them unique properties, are discussed. Separation of particles from aqueous solution using magnetic technology is more convenient compared to conventional techniques, such as filtration and centrifugation. The adsorbents described in this thesis are effective for adsorption of several types of contaminants, such as heavy metals and different types of dyes.    Magnetic microspheres were synthesised using porous polystyrene microspheres as template. The microspheres were first sulfonated using chlorosulfonic acid followed by stirring in the presence of ferrous chloride which then was oxidised and magnetic nanoparticles were formed on the surface.    The sulfonated microspheres had a surface area of 420 m2/g and the magnetic 175 m2/g, indicative of Fe3O4 nanoparticles were successfully formed in the pores. The weight fraction of the Fe3O4 nanoparticles in the magnetic microspheres was 33 %.    Adsorption and desorption studies of the cationic dye, methylene blue, using mesoporous magnetic microspheres were performed. The results show that the mesoporous magnetic microspheres have good ability to adsorb methylene blue at low concentrations. In a cycle study the adsorption efficiency were nearly 100 % throughout the study. Using a 6/4 EtOH/H2O with saturated KCl solution the desorption efficiency in the cycle study were about 95 %.      The microspheres were used as carriers for TiO2 in order to overcome the problem with the separation of TiO2 from solution. The TGA results show that the microspheres contained about 12 % of TiO2. The TiO2 coated microspheres were used for the photocatalytic degradation of phenol. However, the TiO2 microspheres did not work. This was a result from that the phenol had too little contact with the TiO2. A possible way of solving this problem could be to decrease the size of the microspheres, thus increase the surface area.    Lysozyme was adsorbed and separated using the porous microspheres. The lysozyme adsorption worked best at pH 9.6, which is the pI for lysozyme. The lysozyme could be extracted from the microspheres by using a pH 13 buffer. Also, by using MeOH/H2O and EtOH/H2O solutions with saturated KCl the lysozyme could be desorbed. An adsorption and desorption mechanism was also presented. / Vattenrening med magnetisk teknologi är en ny och alltmer uppmärksammad teknik. Magnetisk separation är ett enkelt och snabbt sätt att separera något från en lösning. Magnetisk separation är mer lätthanterligt jämfört med traditionell separationsteknik såsom centrifugering och filtrering.  Med porösa polystyren mikrosfärer som mall, syntetiserades magnetiska mikrosfärer. Först så sulfonerades mikrosfärerna med klorosulfonisk syra, följt av att de rördes om i en järnkloridlösning. Magnetiska nanopartiklar bildades i porerna och på ytan av mikrosfärerna.    Sulfonerade mikrosfärerna hade en specifik ytarea på 420 m2/g och de magnetiska 175　m2/g, detta indikerar att Fe3O4-nanopartiklar bildades på ytan och i porerna. Massfraktionen av Fe3O4 var 33 %.    Adsorption- och desorptionsstudier på de magnetiska mikrosfärerna utfördes. Färgämnet metylblått användes i studien. Resultaten visade att magnetiska mikrosfärerna hade en bra adsorptionsförmåga vid låga koncentrationer av metylblått. Cykelstudier visade att adsorptionsverkningsgraden var nära 100 % under flera adsorptionscykler. Desorptionsförsök med olika lösningsmedel visade att en mättad KCl 6/4 EtOH/H2O lösning gav en desorptions-verkningsgrad på ca 95 %.   Mikrosfärerna användes som mall och kärna för att syntetisera en TiO2-fotokatalysator, detta för att överkomma problemet som finns med separation av rent TiO2 pulver från lösning. TGA resultaten visade att mikrosfärerna innehöll ca 12 % TiO2. De syntetiserade TiO2-mikrosfärerna användes till att bryta ner fenol fotokatalytiskt. Dock fungerade inte detta experiment. En anledning var att fenolen hade för lite kontakt med TiO2. En lösning på detta problem är att använda mikrosfärer med högre specifik ytarea.    Proteinet lysozym användes som modellprotein för försök att separera proteiner från lösning genom att använda porösa mikrosfärer. Resultatet visade att lysozym kunde adsorberas vid pH 9.6. Med en pH 13 buffer kunde lysozymet sedan extraheras från mikrosfärerna. En mekanism för adsorptionen och desorptionen på mikrosfärerna presenterades.

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