Various nano-fillers can introduce specific functions into polymer and expand their application areas. Myriad properties, such as mechanical, electrical, thermal, or magnetic properties can be combined with original polymer characteristics, including flexible, light weight, and ease of use. These composites can be used to produce multi-functional fibers as the next generation textile or fabrics. In this research, Polyacrylonitrile (PAN) is adopted as the main polymer with different nano-fillers, such as carbon nanotube (CNT), iron oxide nanoparticle, and graphene oxide nanoribbon (GONR). Using gel-spinning technology, PAN-based composite fibers are fabricated in single- or bi-component fibers. Fibers are also characterized for their structure, morphology, mechanical properties, as well as for their electrical, thermal, or magnetic properties. For example, bi-component fibers with polymer sheath and polymer-CNT core as well as polymer-CNT sheath and polymer core are processed. With electrical and thermal conductivity introduced by CNT, such bi-components fibers can be applied for wearable electronics or for thermal management. Joule-heating effect owing to applied electrical current on single component PAN/CNT fibers is also investigated. With controllable electrical conductivity and fiber temperature, this active functional fiber can be applied for temperature regulation fibers or new carbon fiber manufacturing process. Another example is magnetic fiber with superparamagnetic iron oxide nano-particles. These novel magnetic fibers with high strength can be used for actuator, inductors, EMI shielding, or microwave absorption. GONR is also discussed and used to reinforce PAN-based fibers. Several theoretical models are considered to analyze the observed results.

Metal-based engineered nanomaterials (ENMs) have potential to revolutionize diagnosis, drug delivery and manufactured products, leading to greater human ENM exposure. It is crucial to understand ENM pharmacokinetics and their association with biological barriers such as the blood-brain barrier (BBB). Physicochemical parameters such as size and surface modification of ENMs play an important role in ENM fate, including their brain association. Multifunctional ENMs showed advantages across the highly regulated BBB. There are limited reports on ENM distribution among the blood in the brain vasculature, the BBB, and brain parenchyma. In this study, ceria ENM was used to study the effect of size on its pharmacokinetics. Four sizes of ceria ENMs were studied. Five nm ceria showed a longer half-life in the blood and higher brain association compared with other sizes and 15 and 30 nm ceria had a higher blood cell association than 5 or 55 nm ceria. Because of the long circulation and high brain association of 5 nm ceria compared with other sizes, its distribution between the BBB and brain parenchyma was studied. The in situ brain perfusion technique showed 5 nm ceria (99%) on the luminal surface of the BBB rather than the brain parenchyma. For biomedical applications in the central nervous system (CNS), it is vital to develop stable and biocompatible ENMs and enhance their uptake by taking advantage of their unique properties. Cross-linked nanoassemblies entrapping iron oxide nanoparticles (CNA-IONPs) showed controlled particle size in biological conditions and less toxicity in comparison to Citrate-IONPs. CNA-IONPs considerably enhanced MRI T2 relaxivities and generated heat at mild hyperthermic temperatures (40 ~ 42°C) in the presence of alternating magnetic field (AMF). Numerous researchers showed mild whole body hyperthermia can increase BBB permeability for potential brain therapeutic application. Compared to conventional hyperthermia, AMF-induced hyperthermia increased BBB permeability with a shorter duration of hyperthermia and lower temperature, providing the potential to enhance IONP flux across the BBB with reduced toxicity. Overall, ENMs with optimized physicochemical properties can enhance their flux across the BBB into the brain with desirable pharmacokinetics, which provide great potential for diagnosis and therapy in the CNS.

<p>Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates.</p><p>The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied. The experiments were conducted with urban storm water and with a reference solution (10 mM NaNO3), both containing the same concentration of heavy metals (approx. 1 μM). The two materials with the best results were further investigated in a column study, where the capacity of the filter was tested. Chemical equilibrium calculations using the program Visual MINTEQ were performed in order to assess the role of precipitation as a mechanism for removal.</p><p>The results show that the blast-furnace slag was the most effective filter material and that it has great potential to be used as a heavy metal remover. Also the iron oxide coated sand worked satisfactory. The highest degree of removal was obtained for lead, cadmium and nickel, for which the removal efficiency exceeded 90% after a load of 300 times the water volume in the columns. For some metals, mainly copper, chromium and mercury the dissolved organic matter affected the removal negatively. The chemical mechanisms causing the removal are specific adsorption to the surfaces of the materials, and for the blast-furnace slag probably precipitation of insoluble metal sulfides.</p> / <p>Starkt förorenat dagvatten som rinner av från exempelvis motorvägar, kan innehålla betydliga mängder tungmetaller som kan orsaka skada om de kommer ut i omgivande vattendrag. En billig metod för tungmetallavskiljning, som inte kräver så mycket underhåll, skulle kunna vara att använda reaktiva filtermaterial bestående av restprodukter eller andra mineraliska lågkostnadsmaterial. Reaktiva filter fungerar som metallavskiljare genom att de lösta metalljonerna binder till ytgrupper på filtermaterialen eller att svårlösliga utfällningar bildas.</p><p>Förmågan att avskilja sju tungmetaller (Cr, Cd, Cu, Ni, Zn, Pb och Hg) ur dagvatten har undersökts för fyra mineraliska filtermaterial, kalciumoxiddopad masugnsslagg, järnoxidsand, olivin och nefelin. Studien inleddes med skakförsök där adsorptionens pH-beroende undersöktes. Försöken gjordes dels med dagvatten, dels med en referenslösning (10 mM NaNO3) med samma tungmetallkoncentration (ca 1μM). Detta gjordes för att studera effekter av löst organiskt material och andra ligander på adsorptionen. Därefter testades de material som uppvisat bäst resultat i skakförsöket i kolonnförsök, ett försök som mer efterliknar en praktisk tillämpning och där filtrets kapacitet kan studeras. Genom kemiska jämviktsberäkningar med programmet Visual MINTEQ var det möjligt att undersöka om bildningen av svårlösliga metallutfällningar bidrog till metallavskiljningen.</p><p>Resultaten visar att slaggen var det effektivaste filtermaterialet och att detta har stor potential att användas för avskiljning av tungmetaller. Även järnoxidsanden fungerade tillfredsställande. De metaller som avskiljdes bäst var bly, kadmium och nickel, för vilka avskiljningen var > 90 % i kolonnförsöket efter en belastning motsvarande 300 gånger vattenmängden i kolonnerna. För vissa metaller, främst koppar, krom och kvicksilver, försämrades avskiljningen betydligt när löst organiskt material fanns närvarande. Mekanismerna som står för avskiljningen är till störst del adsorption till grupper på filtermaterialens ytor, men bildning av svårlösliga metallsulfider är också tänkbar för slaggen.</p>

L'objectif de ce travail est d'étudier une stratégie catalytique originale, consistant à insérer par imprégnation, au sein de la matrice lignocellulosique du bois, un sel métallique de Ni ou Fe, dont les phases catalytiquement actives pour la conversion des goudrons sont générées in-situ au cours de l'étape de pyrolyse. La caractérisation des échantillons de bois imprégné révèle que l'insertion des cations métalliques fait intervenir des mécanismes d'adsorption électrostatique, d'échange ionique et de complexation au sein des hémicelluloses, de la lignine et des microfibrilles de cellulose, assurant un état élevé de dispersion du métal dans la matrice lignocellulosique. L'étude de l'évolution des espèces de Ni au cours de la pyrolyse du bois met en évidence la formation de nanoparticules (NPs) de Ni0 quasi-monocristallines dans la gamme de température 400-500°C, les atomes de carbone jouant le rôle d'agent réducteur. Dans la même gamme de température, les espèces de Fe sont transformées en NPs de FeOx amorphes. Les tests de pyrolyse à 700°C révèlent que le nickel est plus efficace pour augmenter la production de H2 et réduire la formation d'hydrocarbures aromatiques, tandis que le fer est plus performant pour réduire la production totale de goudrons. D'un point de vue mécanistique, la présence des espèces métalliques, très dispersées dans la matrice lignocellulosique, impacte considérablement les mécanismes primaires de pyrolyse. De plus, les réactions secondaires de pyrolyse sont fortement modifiées par la génération in-situ des NPs de Ni0 et de FeOx, considérées comme les phases actives pour les réactions de conversion des goudrons et la réaction du gaz à l'eau. / This exploratory research work aimed at studying an original catalytic strategy for biomass gasification which consists in inserting into the lignocellulosic matrix of wood, by impregnation, a salt of Ni or Fe whose catalytically active phases for tar conversion reactions are generated in-situ during the pyrolysis stage. The characterization of the metal impregnated wood samples reveals that electrostatic adsorption, ion-exchange and metal complexation within hemicelluloses, lignin and cellulose microfibrills are involved in the mechanisms of metal cations insertion, resulting in a very high metal dispersion into the lignocellulosic matrix. The study of the nickel species evolution during wood pyrolysis demonstrates the formation of quasi-monocristalline Ni0 nanoparticles (NPs) in the temperature range 400-500°C, the carbon atoms acting as the reducing agent. In the same temperature range, the Fe species are transformed into amorphous FeOx NPs. The pyrolysis tests performed at 700°C reveal that the nickel catalyst is more efficient for enhancing H2 production and reducing the formation of aromatic hydrocarbons, whereas the iron catalyst exhibits better performances for reducing total tar production. From a mechanistic standpoint, it is suggested that the presence of highly dispersed metal species into the lignocellulosic matrix strongly impacts the mechanisms of primary pyrolysis. Moreover, the secondary pyrolysis reactions are strongly modified by the in-situ generation of Ni0 and FeOx NPs considered as the active phases for tar conversion and water gas shift reactions. Potential interests of the new nanocomposite materials Ni0/C and FeOx/C as obtained are discussed.

Lung cancer is one of the leading causes of cancer deaths in the United States. Radiation and chemotherapy are conventional treatments, but they result in serious side effects and the probability of tumor recurrence remains high. Therefore, there is an increasing need to enhance the efficacy of conventional treatments. Magnetic nanoparticles have been previously studied for a variety of applications such as magnetic resonance imaging contrast agents, anemia treatment, magnetic cell sorting and magnetically mediated hyperthermia (MMH). In this work, dextran coated iron oxide nanoparticles were developed and functionalized with peptides to target the nanoparticles to either the extracellular matrix (ECM) of tumor tissue or to localize the nanoparticles in subcellular regions after cell uptake. The magnetic nanoparticles were utilized for a variety of applications. First, heating properties of the nanoparticles were utilized to administer hyperthermia treatments combined with chemotherapy. The nanoparticles were functionalized with peptides to target fibrinogen in the ECM and extensively characterized for their physicochemical properties, and MMH combined with chemotherapy was able to enhance the toxicity of chemotherapy. The second application of the nanoparticles was magnetically mediated energy delivery. This treatment does not result in a bulk temperature rise upon actuation of the nanoparticles by an alternating magnetic field (AMF) but rather results in intracellular damage via friction from Brownian rotation or nanoscale heating effects from Neél relaxations. The nanoparticles were functionalized with a cell penetrating peptide to facilitate cell uptake and lysosomal escape. The intracellular effects of the internalized nanoparticles alone and with activation by an AMF were evaluated. Iron concentrations in vivo are highly regulated as excess iron can catalyze the formation of the hydroxyl radical through Fenton chemistry. Although often a concern of using iron oxide nanoparticles for therapeutic applications, these inherent toxicities were harnessed and utilized to enhance radiation therapy. Therefore, the third application of magnetic nanoparticles was their ability to catalyze reactive oxygen species formation and increase efficacy of radiation. Overall, iron oxide nanoparticles have a variety of cancer therapy applications and are a promising class of materials for increasing efficacy and reducing the side effects of conventional cancer treatments.

One approach that has demonstrated success in the field of molecular imaging utilizes microparticles of iron oxide (MPIO) conjugated to specific antibodies and/or peptides to provide contrast effects on MRI in relation to the molecular expression of a specified target. The experimental aims of this thesis were 1) to investigate the ability of VCAM-1 and P-selectin targeted MPIO to detect the expression of VCAM-1 and P-selectin on the activated endothelium in-vitro and in-vivo in mouse models of renal and cerebral ischemia reperfusion injury, and 2) develop a novel contrast agent for imaging αvβ3-integrin expression in angiogenesis using RGD peptide conjugated MPIO (RGD-MPIO) in-vitro. MPIO (1.0 µm) were conjugated to monoclonal antibodies against VCAM-1 (VCAM-MPIO) or P-selectin (PSEL-MPIO). In vitro, MPIO bound in a dose-dependent manner to tumor necrosis factor (TNF)-alpha stimulated sEND-1 endothelial cells when conjugated to VCAM-1 (R² = 0.88, P<0.01) and P-selectin antibodies (R² = 0.93, P<0.01), reflecting molecular VCAM-1 and P-selectin mRNA and protein expression. Mice subjected to unilateral, transient (30 minutes) renal ischemia and subsequent reperfusion received intravenous VCAM-MPIO and PSEL-MPIO (4.5 mg iron/kg body weight). In ischemic kidneys, MR related contrast effects of VCAM-MPIO were 4-fold higher than unclamped kidneys (P<0.01) and 1.5-fold higher than clamped kidneys of PSEL-MPIO injected mice (P<0.05). VCAM-MPIO binding was less evident in IRI kidneys pre-treated with VCAM-1 antibody (P<0.001). VCAM-1 mRNA expression and VCAM-MPIO contrast volume were highly correlated (R² = 0.901, P<0.01), indicating that quantification of contrast volume reflected renal VCAM-1 transcription. In mice subjected to cerebral ischemia, contrast volume was 11-fold greater in animals injected with VCAM-MPIO versus control IgG-MPIO (P<0.05). Finally, S-nitroso-N-acetylpenicillamine (SNAP) stimulated HUVEC-C cells, which express αvβ3-integrin, showed 44-fold greater RGD-MPIO binding than unstimulated cells (P<0.001) and 4-fold greater RGD-MPIO binding than SNAP stimulated cells blocked with soluble RGD peptide (P<0.001) in-vitro. This thesis demonstrated that targeted MPIO exhibited contrast effects that defined and quantified the molecular expression of specific targets through the use of high-resolution MRI in in-vitro and in-vivo models of vascular inflammation.

Iron oxide nanoparticles have received sustained interest for biomedical applications as synthetic approaches are continually developed for precise control of nanoparticle properties. This thesis presents an investigation of parameters in the benzyl alcohol synthesis of iron oxide nanoparticles. A modified seed growth method was designed for obtaining optimal nanoparticle properties for magnetic fluid hyperthermia. With a one or two addition process, iron oxide nanoparticles were produced with crystallite sizes ranging from 5-20 nm using only benzyl alcohol and iron precursor. The effects of reaction environment, temperature, concentration, and modified seed growth parameters were investigated to obtain precise control over properties affecting radiofrequency heat generation. The reaction A2-24(205)_B2-24(205) produced monodispersed (PDI=0.265) nanoparticles with a crystallite size of 19.5±1.06 nm and the highest radiofrequency heating rate of 4.48 (°C/min)/mg (SAR=1,175.56 W/g, ILP=3.1127 nHm2/kg) for the reactions investigated. The benzyl alcohol modified seed growth method offers great potential for synthesizing iron oxide nanoparticles for radiofrequency hyperthermia.

Sistemas ultrassônicos tiveram uma evolução tecnológica nos últimos anos e isso permitiu que seus recursos de hardware e software pudessem ser explorados para extrair informações, auxiliando em diagnósticos e tratamentos mais eficazes. Através da análise do comportamento mecânico de tecidos moles, técnicas como elastografia estática, vibroacustografia, elastografia transiente e elastografia remota tiveram seu papel reconhecido na complementação do diagnóstico clínico. Contudo, a propagação destas técnicas na medicina tem sido restringida pela acessibilidade às tecnologias utilizadas, ausências de parâmetros quantitativos, dificuldade da excitação em estruturas profundas e acesso a informações em níveis moleculares. Este estudo aborda o desenvolvimento de um protocolo para efetuar medidas quantitativas de viscoelasticidade em tecidos moles marcados com nanopartículas de óxido de ferro usando excitação magnética e medição ultrassônica. Ao aplicar uma força magnética pulsada em um meio fluido marcado com nanopartículas magnéticas, um movimento é induzido, gerando uma onda de cisalhamento que se propaga pelo tecido. A propagação dessa onda é mapeada usando a técnica de ultrassom pulso-eco e processamento de dados usando métricas de similaridades entre ecos (mapa de rf) consecutivos. Nos estudos realizados em mimetizadores de tecidos moles (phantom) com características mecânicas equivalentes ao tecido biológico, a amplitude de deslocamento dessas ondas é da ordem de micrometro. Através da medida da velocidade deslocamento dessa onda avaliou-se o melhor modelo reológico para quantificar os parâmetros mecânicos de viscosidade e elasticidade. Os resultados mostraram a eficiência desta técnica ao quantificar os valores viscoelásticos condizentes com a literatura e a comprovação da análise de tecidos moles marcado com nanopartículas excitadas com campo magnético de baixa intensidade, possibilitando uma avaliação em âmbito molecular em tecidos moles. / Ultrasonic systems had a technological development in recent years and allowed their hardware and software resources could be exploited to extract information, assisting in more effective diagnosis and treatment. Through the mechanical behavior analysis of soft tissue techniques such as static elastography, vibroacoustography, transient elastography and remote elastography had recognized role in complementing clinical diagnosis. However, the spread of these techniques in medicine has been restricted by accessibility to the technologies used, quantitative parameters absences, difficulty of deep structures access and information on molecular levels. This study addresses the development of a protocol to make quantitative measurements of viscoelastic soft tissue labeled with iron oxide nanoparticles using magnetic excitation and ultrasonic measurement. By applying a pulsed magnetic force in a fluid medium labeled with magnetic nanoparticles, a motion is induced, generating a shear wave that propagates through the tissue. The propagation of this wave is mapped using the pulse-echo ultrasound technique and data processing using similarities measurements between echoes (rf map) consecutive. In studies of soft tissue-mimicking phantom with mechanical properties equivalent to the biological tissue, the displacement amplitude of these waves is of micrometer order. By measuring the shear wave velocity, it was evaluated the best rheological model for quantifying mechanical parameters of viscosity and elasticity. The results showed the efficiency of this technique to quantify the viscoelastic values consistent with the literature and the evidence of soft tissue analysis labeled excited nanoparticles with low intensity magnetic field, providing an assessment on the molecular level in soft tissues.

Zusammenfassung Kenntnisse über den Zustand und die Entwicklung von Böden sind entscheidend für die Charakterisierung von Ökosystemen und deren Veränderungen. Die weltweite Verbreitung von Eisenoxiden und ihre von der Bodenentwicklung abhängige Konzentration und mineralogische Zusammensetzung machen sie zu geeigneten Indikatoren. Methoden der optische Fernerkundung wurden angewandt, um am Beispiel des Cabo de Gata- Níjar Naturparks, einem semi-ariden Ökosystem in Südostspanien, die Konzentrationen von Eisenoxiden im Boden zu bestimmen und zu kartieren. In der zuerst durchgeführten laborspektroskopischen Studie wurde eine Methode entwickelt, welche den Eisenoxidgehalt (Fed, Citrat-Dithionit extrahierbares Eisenoxid) mit den Eisenabsorptionsbanden verknüpft. Korngrößenabhängige Fed Vorhersagemodelle wurden sowohl für sand- als auch ton-schluff-haltige Proben erstellt. Beide liefern hochgenaue Schätzungen mit weniger als 15% Vorhersagefehler. Ähnliche Werte wurden für korngrößenunabhängige Modelle erreicht. Korngrößenunabhängige Modelle wurden zur Analyse der HyMap-Bilddaten verwendet, da eine pixelbezogene Bestimmung der vorherrschenden Bodentextur nicht möglich war. Die räumliche Verteilung der Fed Konzentration im Untersuchungsgebiet wurde mit einer den Laborergebnissen vergleichbaren Genauigkeit bestimmt. Laboruntersuchungen zum Vegetationseinfluss in Bezug auf Vitalität und Bedeckungsgrad auf die Bodenreflektionsspektren und die Fed Vorhersagegenauigkeit zeigten, dass zuverlässige Abschätzungen bis zu einer Vegetationsbedeckung von ca. 20 % möglich sind. Dementsprechend wurden drei Vorhersagegenauigkeitsklassen definiert, basierend auf der gemeinsamen Detektierbarkeit von Vegetation und Eisenabsorptionsbanden im Bildpixel. Die abgeleitete Fed Verteilungskarte dient der Einschätzung des vorliegenden Bodenzustands und dem Ausweisen von erodierten Oberflächen. Die entwickelte Methode hat aufgrund ihrer Einfachheit ein großes Potential für ein globales Monitoring von sensitiven Gebieten unter der Verwendung von gegenwärtig verfügbaren als auch zukünftigen satellitengestützten Sensoren. / Abstract The knowledge of the soil condition and development is decisive when characterizing and monitoring the change of ecosystems. The global presence of iron oxides and their highly variable concentration and mineralogy reflecting different soil conditions make them a suitable indicator. Optical remote sensing methods are employed to determine and map the soil iron oxide concentrations on the example of the Cabo de Gata-Níjar Natural Park, a semi-arid ecosystem in SE Spain. In an initial laboratory spectroscopy study, a methodology is developed that links iron oxide content (Fed, citrate-dithionite extractable iron oxides) with iron spectral absorption bands. Texture-dependent Fed prediction models are developed for sand- and clay-silt-dominated samples. They yield highly accurate estimations with less than 15 % prediction error. Similar accuracies are achieved from texture-independent models. Texture-independent models are applied to the HyMap image data because a pixel-wise determination of the predominating soil texture is not possible. However, the spatial distribution of Fed concentration in the study area is determined with comparable accuracy as in the laboratory. Laboratory analysis of vegetation vitality and density impact on the soil reflectance spectra and Fed prediction accuracy has shown that reliable estimations are possible until about 20 % leaf cover. Accordingly, three Fed prediction accuracy levels are defined based on the joint detectability of vegetation and iron absorption features. The final Fed prediction map is used to evaluate the current soil conditions and identify potentially eroded soils surfaces. The present method has due to low complexity a high potential for the global monitoring of such sensitive areas from current and future spaceborne sensors.

In der vorliegenden Arbeit wird das Prinzip der chemischen Oberflächenmodifikation als allgemeine Synthesestrategie beschrieben. Davon ausgehend werden verschiedene Ansätze der chemischen Funktionalisierung dargestellt, mit denen die Eigenschaften der erhaltenen Materialien eingestellt werden können. Im Fokus der Arbeit stehen Eisenoxid-Nanopartikel, die über die „Benzylalkohol-Route“ dargestellt werden. Es wird auf Basis dieser einfachen und vielseitig anwendbaren Funktionalisierung die Herstellung von neuartigen Hybridmaterialien gezeigt. Zur Funktionalisierung zweier magnetischer molekularer Rezeptoren wurde eine Synthesestrategie entwickelt, bei der organische Gruppen kovalent angebunden wurden. Der erste Rezeptor kann zur Erkennung von Biomarkern und den Metaboliten von Pharmazeutika eingesetzt werden. Die Beschichtung der Oberflächen der Eisenoxid-Nanopartikel gelang dabei durch die Verwendung von Organosilan-basierten Kopplungsreagenzien. Der zweite Rezeptor konnte zur Auftrennung eines racemischen Gemisches eines chiralen cavitand eingesetzt werden. Die Darstellung von Graphenoxid-Eisenoxid-Kompositen gelang erfolgreich durch ein ex-situ Verfahren. Es wurde der Einfluss der Oberflächenfunktionalitäten auf die Beladung und Verteilung der Eisenoxid-Nanopartikel untersucht. Dazu wurden via Diazoniumchemie verschiedene Funktionalitäten auf der Graphenoxid-Oberfläche eingeführt. Die Entwicklung einer wasserfreien one-pot Synthese von Gold-Eisenoxid-hetero-Nanostrukturen beschrieben wurde. Insbesondere wurden die Auswirkungen kleiner organischer Moleküle auf die Bildung der Heterostrukturen untersucht. / This thesis describes diverse approaches of chemical functionalization as a general strategy to tailor material properties depending on the target application. Particular attention was dedicated to the surface chemistry of iron oxide nanoparticles. Crystalline 10 nm-sized magnetite nanoparticles synthesized through the “benzyl alcohol route” exhibit superparamagnetic behaviour. For this reason they are regarded as suitable solid supports for the fabrication of recoverable devices, which is a fundamental requirement for several of the reported studies. Here it is demonstrated, via the fabrication of novel hybrid materials, that the ease of functionalization of iron oxide nanoparticles renders this material a versatile platform for the development of diverse surface chemistries. A covalent organic functionalization strategy was developed for the synthesis of two recoverable magnetic molecular receptors. The first targeted the recognition of drugs metabolites and biomarkers. It is based on the use of organosilanes coupling agents. A second approach aimed to the heterogeneous resolution of a racemic mixture of an inherently chiral cavitand. Graphene oxide-iron oxide composites were successfully fabricated through an ex-situ approach based on non-covalent interactions between the component phases. The effects of surface functionalities on the loading and distribution of iron oxide nanoparticles were studied by introducing selected functionalities at the graphene oxide surface through diazonium chemistry. Finally, the development of a non-aqueous one-pot synthesis route to gold-iron oxide hetero-nanostructures was described. Particular emphasis was dedicated to study the influence of small organic molecules in promoting the formation of the heterostructures.