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Metal Oxo Polymer Nanobeads As Potential Multi Modal Contrast Agents For Magnetic Resonance Imaging
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Book Synopsis Metal-Oxo Polymer Nanobeads as Potential Multi-Modal Contrast Agents for Magnetic Resonance Imaging by : Vidumin Dahanayake
Download or read book Metal-Oxo Polymer Nanobeads as Potential Multi-Modal Contrast Agents for Magnetic Resonance Imaging written by Vidumin Dahanayake and published by . This book was released on 2018 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: The stability of these nanobeads in simulated biological conditions was extensively studied for potential use as contrast agents. Metal leaching, hydrodynamic diameter and relaxation were monitored over time. Hemo-compatibility, cellular uptake and viability in vitro was also investigated along with blood clearance and biodistribution in vivo. Finally the feasibility of these materials for MRI contrast enhancement and their integrity after opsonization was tested using live mouse models.
Book Synopsis Metal-Oxo Containing Polymer Nanobeads As Potential Contrast Agents for Magnetic Resonance Imaging by : Michele Huelar Pablico
Download or read book Metal-Oxo Containing Polymer Nanobeads As Potential Contrast Agents for Magnetic Resonance Imaging written by Michele Huelar Pablico and published by . This book was released on 2011 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most common MRI contrast agents that are in clinical use today are gadolinium chelates and superparamagnetic iron oxide nanoparticles, both of which have their own advantages in terms of contrast enhancement properties. In the past few years, however, there has been interest in utilizing metal-containing clusters for MRI contrast enhancement as these materials bridge the gap between the constrained structure and magnetic properties of the gadolinium chelates with the superparamagnetic behavior of the iron oxide nanoparticles. Recently, metallic clusters containing Mn and Fe metal centers have received increased attention mainly because of their potential for high spin states and benign nature.
Book Synopsis Magnetic Nanoparticles in Human Health and Medicine by : Costica Caizer
Download or read book Magnetic Nanoparticles in Human Health and Medicine written by Costica Caizer and published by John Wiley & Sons. This book was released on 2021-11-22 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic Nanoparticles in Human Health and Medicine Explores the application of magnetic nanoparticles in drug delivery, magnetic resonance imaging, and alternative cancer therapy Magnetic Nanoparticles in Human Health and Medicine addresses recent progress in improving diagnosis by magnetic resonance imaging (MRI) and using non-invasive and non-toxic magnetic nanoparticles for targeted drug delivery and magnetic hyperthermia. Focusing on cancer diagnosis and alternative therapy, the book covers both fundamental principles and advanced theoretical and experimental research on the magnetic properties, biocompatibilization, biofunctionalization, and application of magnetic nanoparticles in nanobiotechnology and nanomedicine. Chapters written by a panel of international specialists in the field of magnetic nanoparticles and their applications in biomedicine cover magnetic hyperthermia (MHT), MRI contrast agents, biomedical imaging, modeling and simulation, nanobiotechnology, toxicity issues, and more. Readers are provided with accurate information on the use of magnetic nanoparticles in diagnosis, drug delivery, and alternative cancer therapeutics—featuring discussion of current problems, proposed solutions, and future research directions. Topics include current applications of magnetic iron oxide nanoparticles in nanomedicine and alternative cancer therapy: drug delivery, magnetic resonance imaging, superparamagnetic hyperthermia as alternative cancer therapy, magnetic hyperthermia in clinical trials, and simulating the physics of magnetic particle heating for cancer therapy. This comprehensive volume: Covers both general research on magnetic nanoparticles in medicine and specific applications in cancer therapeutics Discusses the use of magnetic nanoparticles in alternative cancer therapy by magnetic and superparamagnetic hyperthermia Explores targeted medication delivery using magnetic nanoparticles as a future replacement of conventional techniques Reviews the use of MRI with magnetic nanoparticles to increase the diagnostic accuracy of medical imaging Magnetic Nanoparticles in Human Health and Medicine is a valuable resource for researchers in the fields of nanomagnetism, magnetic nanoparticles, nanobiomaterials, nanobioengineering, biopharmaceuticals nanobiotechnologies, nanomedicine, and biopharmaceuticals, particularly those focused on alternative cancer diagnosis and therapeutics.
Book Synopsis Design and Applications of Nanoparticles in Biomedical Imaging by : Jeff W.M. Bulte
Download or read book Design and Applications of Nanoparticles in Biomedical Imaging written by Jeff W.M. Bulte and published by Springer. This book was released on 2016-11-25 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the most recent advances in using nanoparticles for biomedical imaging, including magnetic resonance imaging (MRI), magnetic particle imaging (MPI), nuclear medicine, ultrasound (US) imaging, computed tomography (CT), and optical imaging. Topics include nanoparticles for MRI and MPI, siRNA delivery, theranostic nanoparticles for PET imaging of drug delivery, US nanoparticles for imaging drug delivery, inorganic nanoparticles for targeted CT imaging, and quantum dots for optical imaging. This book serves as a valuable resource for the fundamental science of diagnostic nanoparticles and their interactions with biological targets, providing a practical handbook for improved detection of disease and its clinical implementation.
Download or read book Nanomedicine written by Marc J. Williams and published by Elsevier Inc. Chapters. This book was released on 2013-09-19 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The past two decades have seen a surge in the development and application of nanoparticles for biomedical uses, with a focused effort on engineering particles for ‘theranostic’ applications where diagnosis and disease treatment are possible using a single platform. Magnetic nanoparticles, in particular, are ideal candidates for this kind of multimodal action, given their potential use spans magnetic resonance (MR) imaging, magnetic hyperthermia and targeted drug delivery. This is due to unique properties their size bestows on them. Here, we examine these properties of magnetic nanoparticles and how they govern the particle efficacy for a desired application. Given the intimate link between synthetic approach chosen and subsequent properties, we will also discuss typical and emerging routes to magnetic nanoparticle preparation. We will, in detail, describe the uses of magnetic nanoparticles as diagnostic and therapeutic tools, with particular emphasis on their use as MR contrast agents and the most recent developments in targeted drug delivery. Finally, we will present an outlook for the future of these important materials.
Book Synopsis Advancements in Branched Bottlebrush Polymers for Responsive, Targeted Imaging by : Molly Ann Sowers
Download or read book Advancements in Branched Bottlebrush Polymers for Responsive, Targeted Imaging written by Molly Ann Sowers and published by . This book was released on 2015 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-modality and stimuli responsive nanoparticles are promising platform materials for medical imaging and diagnostics. Specifically magnetic resonance imaging (MRI) and nearinfrared (NIR) fluorescent probes can be used in combination to visualize biodistribution and in vivo clearance rates. We reasoned that through the use of a nitroxide radical MRI contrast agent along with a NIR fluorophore it would be possible to study these phenomena along with nitroxide reduction in vivo. Thus, we have developed branched bottlebrush copolymers that display compensatory fluorescence response to nitroxide reduction that enables correlation of MRI contrast, fluorescence intensity, and spin concentration in tissues. These polymers were synthesized by ring-opening metathesis copolymerization of two new branched macromonomers: one carries a bis-spirocyclohexyl nitroxide and the other the NIR dye Cy5.5. Promising preliminary results with the resulting polymers in solution MRI and NIR imaging studies as well as in vitro toxicity led us to explore the potential of these materials for in vivo applications. Though nitroxide agents are promising organic agents for MRI applications, clinically, gadolinium-based MRI contrast agents are most common due to their high relaxivity and relatively low toxicity when bound to chelating ligands. We have also explored the idea of incorporation of gadolinium agents into our branched bottlebrush copolymer platform through the design of Gd-based branched macromonomers. While the fluorescence redox effects described in the nitroxide system above would not be applicable, chelated Gd could be used in much smaller concentration to provide similar MRI contrast. In this way, a small percentage of Gd could be added as an MRI tag to any polymer synthesized by ROMP. A natural extension of the work described above is the incorporation of cellular targeting moieties for tissue-selective imaging. Toward this end, we propose the incorporation of known cellular targeting ligands onto the surface of branched bottlebrush polymers through the synthesis of end-functionalized branched macromonomers. The synthesis of several targeting ligands is described, alongside synthesis and characterization of positively charged nanoparticles for improved cellular uptake and ionic coordination of hyaluronic acid or other negatively charged polymers.
Book Synopsis Magnetic Nanoheterostructures by : Surender Kumar Sharma
Download or read book Magnetic Nanoheterostructures written by Surender Kumar Sharma and published by Springer Nature. This book was released on 2020-03-02 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains most updated information on synthesis of magnetic nanohybrids, their physio-chemical properties, and key biological applications. It highlights the complexity of nanoheterostructures, especially magnetic metal oxides, ferrites and doped magnetic nanomaterials, and discusses their potential applications in the early detection, imaging and treatment of cancer. It also covers the toxicity and risk assessment of multifunctional nanomaterials. Providing an overview of magnetic nanoheterostructures, it appeals to a wide audience, from beginners and graduate-level students to experts in academia and industry.
Book Synopsis An Investigation of Nanoparticles as Potential Contrast Agents for Magnetic Resonance Imaging by : Amal Hamed
Download or read book An Investigation of Nanoparticles as Potential Contrast Agents for Magnetic Resonance Imaging written by Amal Hamed and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Magnetic Nanoparticles by : K. S. Joshy
Download or read book Magnetic Nanoparticles written by K. S. Joshy and published by Springer Nature. This book was released on 2021-05-17 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume covers current research in the usage of magnetic nanoparticles for drug delivery. It discusses synthesis methods, stabilizers used for surface coating on MNPs, and potential target ligands which can be used to ferry payloads to the targeted disease region. It also highlights the factors affecting delivery efficiency and toxicity, as well as the different routes of administration. The content also focus on the use of these carriers for gene therapy and to target brain tumors. This volume will be of interest to researchers working on drug discovery and delivery platforms.
Book Synopsis Synthesis of Biocompatible Nanoparticulate Coordination Polymers for Diagnostic and Therapeutic Applications by : Murthi S. Kandanapitiye
Download or read book Synthesis of Biocompatible Nanoparticulate Coordination Polymers for Diagnostic and Therapeutic Applications written by Murthi S. Kandanapitiye and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The combination of nanotechnology with medicinal chemistry has developed into a burgeoning research area. Nanomaterials (NMs) could be seamlessly interfaced with various facets in biology, biochemistry, medicinal chemistry and environmental chemistry that may not be available to the same material in the bulk scale. This dissertation research has focused on the development of nanoparticulate coordination polymers for diagnostic and therapeutic applications. Modern imaging techniques include X-ray computed tomography (CT), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and positron emission tomography (PET). We have successfully developed several types of nanoparticulate diagnostics and therapeutics that have some potential usefulness in biomedicine. Synthesis and characterization of nanoparticulate based PET (Positron emission tomography)/SPECT (Single photon emission computed tomography) are discussed in chapter 3. For the preparation of 68Ga-radiopharmaceuticals, fast formation kinetics are required owing to the short half-life of 68Ga. Our accelerated synthesis involving the aqueous solution and efficient-easy purification of PB NPs would be highly desirable. In addition, easy preparation and fast purification allow physicians to gain considerable time for imaging even with relatively low concentration of radiopharmaceuticals. We demonstrate for the first time the use of Ga(III) doped colloidal solutions of Prussian blue (PB) as a novel radioactive Ga(III) delivering agent. The PET/SPECT imaging modalities provide information on molecular processes using radiolabeled imaging agents; on the other hand PET and SPECT gives limited anatomical details and spatial resolution as a major disadvantage, regardless of their high-sensitivity in tracking in vivo biomarkers. Also we have described for the first time a novel nanoparticulate solid-state compound that contains both Gd(III) (f7, S=7/2) and Ga(III) as dopants in the network structure. The dopant Gd(III) and radioactive Ga(III) render the T1- weighted MRI imaging active and PET-SPECT imaging active, respectively. Prussian blue nanoparticles are the smartest option as a scaffold material for the development of multimodal agent due to their biocompatibility, high water dispersability and easy with which its surface can be modified to get better pharmacokinetic properties. Such hybrid imaging techniques allow physicians to precisely co-register anatomical and functional information in a single scanning session without removing the patient from the bed, which would offer increased diagnostic accuracy. In chapter 4, preparation and potential utility of non-gadolinium based MRI contrast agent are reported for T1-weighted application. As far as the solely effectiveness of relaxation is concerned, Gd-based T1-weighted MRI contrast agents have excellent enhancement of image contrast but they have risks of biological toxicity. Consequently, the search for T1-weighted CAs with high efficacy and low toxicity has gained attention toward the Mn(II) and Fe(III). Fe(III) is considered to be more toxic to cells because free ferric or ferrous ions can catalyze the production of reactive oxygen species via the Fenton reactions. Paramagnetic chelates of Mn(II) could be employed as T1-weighted CAs. However, it is challenging to design and synthesize highly stable Mn(II) complexes that could maintain the integrity when administered to living system. Chapter 4 describes the synthesis and utility of nanoparticulate Mn analogue of Prussian blue (K2Mn3[FeII(CN)6]2) as an effective T1 MRI contrast agent for cellular imaging X-ray computed tomography is capable of delineating the 3-D images of soft tissues with superb quality. The variation of X-ray attenuation from one tissue to another is used to generate the well spatial resolved superb quality images. Exogenous radiopaque agents are necessary for the superb visualization of different types of soft tissues. Heavy metals with high atomic number are better suited for biomedical applications to enhance the image contrast due to their high mass attenuation coefficient. Bismuth (Z- 83) is the nonradioactive, heaviest, nontoxic element available among the other closest neighbors (Hg, Tl, Pb and Po) of the periodic table. We have set out to search for compounds that are hydrolytically stable, more efficient and more amenable in terms of biocompatibility. Moreover this new discovery can significantly reduce the average radiation dose in one CT scan. We have discovered a simple one-step aqueous solution route for preparing biocompatible and ultra-small bismuth oxyiodide BiOI nanoparticles and investigated their potential application as an efficient CT contrast agent. Our ultra-small monodisperse BiOI NPs have excellent water dispersability, thermodynamic stability, kinetic inertness, high biocompatibility and superior attenuation power, suggesting their potential as an organ-specific CT contrast agent that may fill the gap left by the other nanoparticulate and iodine-based CT contrasting agents. The chapter 6 of this dissertation discusses synthesis and characterization of novel nanoparticulate therapeutics and theranostics. D-penicillamine has the highest efficacy, and hence is currently the most widely used drug for WD across the world. We have prepared the D-PEN-conjugated Au NPs of the average size of 16 ± 2 nm with superb water dispersability, and examined the kinetics and selectivity of copper binding of such NPs in aqueous solution. We also studied the cellular uptake, cytotoxicity and intracellular copper removal of these NPs to demonstrate their potential as a novel cell-penetrable copper detoxifying agent. To the best of our knowledge, this is the first attempt to show that D-PEN can be tailor-made as a new-generation biocompatible intracellular copper detoxifying drug. Despite of its many adverse side effects, D-PEN remains as a treatment for WD because of its proven efficacy. It seems clear that there is an unmet clinical need for a novel WD drug with improved organ-specificity and reduced systemic toxicity. Our approach of tackling these problems focuses on the development of cell-permeable copper-depleting nanoparticles that can be surface-engineered to be potentially organ-specific when targeting agents are used to form new-generation drugs for WD. The latter part of chapter 6, we describe the synthesis, characterization of zinc analogue of Prussian blue (K2Zn3[Fe(CN)6]2-ZnPB) for intracellular copper detoxification. ZnPB NPs are highly water-dispersible, biocompatible and capable of penetrating cells and selectively remove the intracellular copper. Besides the copper detoxification ability of K2Zn3[Fe(CN)6]2, the concomitant copper sensing activity of ZnPB NPs was investigated owing to its selective copper ion exchange kinetics and the change in r1 relaxivity. Further, our K2Zn3[Fe(CN)6]2 NPs exhibit anti-angiogenic activity and such effect on HuVEC cells could easily be reversed by replenishing the copper supply. This observation suggested that our nanoparticles show their activity on angiogenesis inhibition by depleting copper which acts as a cofactor in a number of angiogenesis promoters.
Book Synopsis Metal Oxide Nanoparticles as Potential MRI Contrast Agents by : Naomi E. Jones
Download or read book Metal Oxide Nanoparticles as Potential MRI Contrast Agents written by Naomi E. Jones and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Polymeric Nanoparticle and Bioconjugate MRI Contrast Agents for In Vivo Imaging by : Clare Lee Matilda Le Guyader
Download or read book Polymeric Nanoparticle and Bioconjugate MRI Contrast Agents for In Vivo Imaging written by Clare Lee Matilda Le Guyader and published by . This book was released on 2017 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoparticles are the hallmark of nanomedicine, proving clinically relevant for the delivery of therapeutic and diagnostic drugs. Nanomaterials are highly versatile, with the ability for scientists to tailor composition and function to suit the desired application. Herein, two types of nanocarriers are investigated in the context of magnetic resonance imaging contrast agents: polymeric nanoparticles and protein carriers. A key research focus in applying nanoparticles for drug delivery is in understanding physicochemical properties affecting in vivo fate. Shape or morphology of a particle is a vastly underutilized property in the design of nanoparticles, and is difficult to predictably control in the context of polymeric nanoparticles. Investigations of block copolymer nanoassemblies evaluate effects of the polymer structure and the self-assembly process to form interesting and diverse structures. In this work, ring-opening metathesis polymerization is employed to prepare and study block copolymer amphiphile self-assembly. First, a small library of amphiphiles are prepared in which the hydrophobic block functionality is varied. In varying the polymer structure and the solvent for assembly, different morphologies are produced, including small and large spheres, cylinders, y-junctions, and rods. In several cases, one polymer can take on different morphologies depending on the organic cosolvent used during micellization, highlighting the importance of assembly conditions and dynamics in forming kinetically trapped structures versus thermodynamically stable structures. These are important considerations when designing, synthesizing, and formulating polymeric nanoparticles for in vivo applications. Next, direct incorporation of a gadolinium based contrast agent for magnetic resonance imaging is studied. A novel monomer and chain transfer agent of a gadolinium-chelate are used to directly incorporate the contrast agent in to a polynorbornene polymer backbone. The resulting spherical and fibrillar nanoparticles exhibited enhanced relaxivity and are studied as MRI contrast agents using live imaging in murine models. Finally, a fatty acid ligand is conjugated to a gadolinium-based contrast agent is prepared and formulated with human serum albumin. In formulation with HSA, the agent exhibits high relaxivity and prolonged blood circulation. In addition, therapeutic conjugates formulated with HSA are evaluated for in vitro cytotoxicity and found to be effective in tumor growth suppression in vivo.
Book Synopsis Stealth Nanoparticles for Preclinical X-rays Imaging and Multimodal X-rays/MRI (magnetic Resonance Imaging) Imaging by : Justine Wallyn
Download or read book Stealth Nanoparticles for Preclinical X-rays Imaging and Multimodal X-rays/MRI (magnetic Resonance Imaging) Imaging written by Justine Wallyn and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomedical imaging is nowadays an essential tool to establish a diagnosis by means of observation of tissues and biological fluids. Combination of imaging instrument with contrast enhancers is a key to obtain clear delineation of a desired tissue by accumulation of a contrast agent into this specific target. The two main imagers are the X-ray scanner and the magnetic resonance imaging (MRI).These imagers are frequently used in conjuncture. Typically, small hydrosoluble iodinated molecules are used as contrasting material for radiography whereas MRI involves magnetic materials like iron oxide nanoparticles. In this work, we proposed two novel contrast agents, the first one was aiming to form an alternative to iodinated contrast agents suffering from fast excretion and causing renal toxicity whereas the second one was aiming at providing bimodal contrasting ability to facilitate access to bimodal imaging procedure in clinics. In the first case, iodinated polymeric nanoparticles, serving for preclinical X-ray imaging were formulated by nanoprecipitation technique. Parameters of formulation were elucidated to provide nanoparticles with size distribution suitable for in vivo administration and high iodine content for contrast enhancement. In vivo study revealed the efficacy of our nanoparticles to clearly visualize liver and spleen and limiting current issues associated with marketed radiopaque contrast agents. The second work achieved was aiming at formulating bimodal lipids-based nanocarriers capable of yielding contrast enhancement for X-ray imaging and MRI by combining iodinated oil and iron oxide nanoparticles within a nano-emulsion core. This would provide bimodal nanoparticulate platform to carry out fast and efficient dual modal imaging procedures. In this context we succeeded to generate efficient dual modal contrast agent yielding clear visualization of liver and kidney by MRI and liver and spleen by X-ray imaging. Pharmacokinetic profile was so determined thanks to bimodal imaging. Using MRI allowed to show that kidneys eliminated a fraction of the dose whereas X-ray imaging confirmed that both tissues, liver and spleen, were passively targeted. These two studies proposed solutions limiting current issues of radiopaque contrast agents and novel formulations to facilitate bimodal imaging for soft tissues imaging.
Book Synopsis Multifunctional Polymer Platform as Ligand and MRI Contrast Agent for Inorganic Nanocrystals by : Liang Du
Download or read book Multifunctional Polymer Platform as Ligand and MRI Contrast Agent for Inorganic Nanocrystals written by Liang Du and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unique physical and optical properties of inorganic nanocrystals have generated tremendous interest over the past two decades. They have been extensively studied to prepare photovoltaic devices and diagnostic tools. Luminescent quantum dots, gold nanomaterials and iron oxide nanoparticles have found promising success in a broad range of areas including light-emitting diodes, therapeutic tomography, photodynamic therapy drug delivery and magnetic resonance imaging. However, most of the as-prepared nanoparticles are stabilized by hydrophobic coordinating ligands which impede their biological applications. In this dissertation, we summarize the application of poly(isobutylene-alt-maleic anhydride) (PIMA) polymer platform to prepare biocompatible nanomaterials as well as MRI contrast agents. In chapter 2, we designed a new set of multi-coordinating polymer ligands based on the phosphonate anchoring motif and applied them for the surface coating of luminescent quantum dots, gold nanoparticles and iron oxide nanoparticles alike. The ligand is synthesized via nucleophilic addition reaction between poly(isobutylene-alt-maleic anhydride) and amine-modified phosphonate derivatives and short polyethylene glycol hydrophilic blocks, which allows the flexibility to tune the architecture and stoichiometry of the final compound. We find that these phosphonate-based polymers exhibit strong coordinating affinity to ZnS-overcoated quantum dots (QDs), Au nanoparticles (AuNPs) as well as iron oxide nanoparticles (IONPs), yielding nanocrystal dispersions that exhibit good colloidal stability for all three systems. The affinity of these ligands is also preserved when additional coordinating groups are introduced, such as imidazoles. Furthermore, the resulting polymer-coated nanocrystals are easily functionalized with reactive groups, introduced along the polymer chain during synthesis. They are compact enough to allow implementation of resonance energy transfer coupling of luminescent QDs to proximal dyes. Affinity between the ligands and gold nanoparticle surfaces was compared to that of thiol groups using NaCN digestion tests. In Chapter 3, we designed a novel set of polymeric multicoordinating ligands based on the N-heterocyclic carbene (NHC) anchoring molecules and applied them for stabilizing luminescent quantum dots in aqueous media. The ligand is synthesized via nucleophilic addition reaction between amine-appended imidazole/poly(ethylene glycol) compounds and poly(isobutylene-alt-maleic anhydride) (PIMA), which yields coordinating ligands with tunable number of lateral motifs. We find that these NHC-based polymers exhibit fast and robust coordinating affinity to CdSe QDs overcoated with ZnS shells. The removal of pristine coating and the generation of carbene are demonstrated by NMR techniques. 13C and HMBC NMR spectroscopy also confirm the existence of the carbene-carbon which is crucial for binding the transition-metals on QD surfaces. These QDs exhibit essentially identical absorption and emission features before and after the cap exchange, and their compact architecture is demonstrated by diffusion ordered NMR spectroscopy. Agarose gel electrophoresis measurements indicate that the polymer coating imparts the QDs good compatibility in different pH, and it prevents protein adsorption. Excellent colloidal stability of these QD samples is observed in a wide range of competitive conditions over extended period of time. In Chapter 4, we detail the design of a set of polymeric contrast agents used for 19F magnetic resonance imaging (19F MRI). The agent is synthesized via a nucleophilic addition reaction between poly(isobutylene-alt-maleic anhydride) and amine-appended fluorinated precursors and short polyethylene glycol (PEG) coils, which permits the tunability of the stoichiometric architecture. We find that introducing PEG moieties to ~70% of the repeating units on the polymers is essential for balancing the hydrophobic feature of fluorine groups. We show that the signal to noise ratio (SNR) of the contrast agents is highly dependent on the arm-length between the polymer scaffold and the magnetic responding CF3 groups. A series of lateral fluorinated chains with different lengths are installed onto the polymers, and extended transverse relaxation time (T2) is observed from the agents with long arm-lengths. Data from Diffusion-ordered NMR spectroscopy (DOSY) indicate that using a pegylated arm between the macromolecule and CF3 groups does not greatly increase the hydrodynamic size of the resulting contrast agents. The effectiveness of inserting the arm is also confirmed by phantom images collected from agent dispersions with different concentrations. In Chapter 5, we provide a summary of the versatility of PIMA platform and discuss the outlook of these multifunctional polymeric molecules.
Book Synopsis Novel Superparamagnetic Nanoparticles as MRI Contrast Agents by : Carlos Bárcena
Download or read book Novel Superparamagnetic Nanoparticles as MRI Contrast Agents written by Carlos Bárcena and published by . This book was released on 2008 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, magnetic nanoparticles have played an increasing role in biomedical applications and have been the subject of extensive research investigations. Physical properties, including nanoparticle size, composition and surface chemistry, vary widely and influence their biological and pharmacological properties and, ultimately, their clinical applications and utilities. Among different magnetic nanoparticles, superparamagnetic iron oxide nanoparticles (SPIOs) were found non-toxic and used in multiple applications including magnetic resonance imaging (MRI) contrast agents, molecular and cellular imaging, and potential therapeutic options. Herein, a mixed spinel strategy was devised to increase the magnetization of SPIO by incorporation of non-magnetic Zn 2+ . Addition of a normal spinel (ZnFe 2 O 4) to an inverse spinel (Fe 3 O 4) results in a magnetic disorder which leads to increased magnetization. Hydrophobic Zn x Fe 1-x O Fe 2 O 3 (x = 0.34) nanoparticles encapsulated in polymeric micelles exhibited increased T 2 relaxivity and sensitivity of detection over commercially used Feridex ® sample. The superb MR relaxivity of these Zn-SPIO nanoparticles and stability of micellar carriers make them excellent candidates for in vivo MR imaging of cancer.
Book Synopsis Nanomaterials for Multimodal Molecular Imaging by : Irene Fernández Barahona
Download or read book Nanomaterials for Multimodal Molecular Imaging written by Irene Fernández Barahona and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of hybrid probes for multimodal molecular imaging is changing the diagnosis and characterisation of complex pathologies. The fusion of the outstanding sensitivity of positron emission tomography (PET) and the excellent anatomical resolution of magnetic resonance imaging (MRI), provides an ideal combination of structural and anatomical information, which is key to expand the application of molecular imaging for the diagnosis of complex and multifactorial diseases. Iron oxide nanoparticles (IONPs) have been traditionally used as negative (T2) contrast agents, darkening tissues or areas in which they accumulate. However, in recent years there has been a great amount of research focusing on the production of IONPs for positive (T1) contrast MRI. One of the most appealing properties that nanoparticles usually offer is the possibility of tailoring their synthesis and functionalisation to obtain probes that generate or enhance the signal in more than one imaging modality, via incorporation of moieties in the core or the surface of the nanoparticle. In this thesis, we developed a novel microwave-assisted method for the synthesis of IONPs coredoped with the positron emitter 68Ga and with relaxometric properties suitable for hybrid T1 MRI/PET imaging. Full characterisation revealed optimal radiochemical properties for PET imaging and excellent relaxometric properties for T1 MR imaging, demonstrating that the combined use of nanotechnology and radiochemistry can render an innovative tool for the dual imaging of biological processes in vivo...
Book Synopsis Surface-modified Nanobiomaterials for Electrochemical and Biomedicine Applications by : Alain R. Puente-Santiago
Download or read book Surface-modified Nanobiomaterials for Electrochemical and Biomedicine Applications written by Alain R. Puente-Santiago and published by Springer Nature. This book was released on 2020-07-27 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.
