Publications by authors named "Thorbjorn T Nielsen"

2-Hydroxypropyl-β-cyclodextrin (HPBCD) is one of the most important cyclodextrin derivatives, finding extensive applications in the pharmaceutical sector. Beyond its role as an excipient, HPBCD achieved orphan drug status in 2015 for Niemann-Pick type C disease treatment, prompting research into its therapeutic potential for various disorders. However, the acceptance of HPBCD as an active pharmaceutical ingredient may be impeded by its complex nature.

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Veratridine (VTD) is a plant neurotoxin that acts by blocking the voltage-gated sodium channels (VGSC) of cell membranes. Symptoms of VTD intoxication include intense nausea, hypotension, arrhythmia, and loss of consciousness. The treatment for the intoxication is mainly focused on treating the symptoms, meaning there is no specific antidote against VTD.

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Filamentous fungi belonging to the genus Fusarium are notorious plant-pathogens that infect, damage and contaminate a wide variety of important crops. Phenamacril is the first member of a novel class of single-site acting cyanoacrylate fungicides which has proven highly effective against important members of the genus Fusarium. However, the recent emergence of field-resistant strains exhibiting qualitative resistance poses a major obstacle for the continued use of phenamacril.

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Controlling the rate of release of molecules from a hydrogel is of high interest for various drug delivery systems and medical devices. A strategy to alter the release profiles of soluble and poorly soluble active ingredients from hydrogels can be to combine the hydrogel forming ability of alginate with the inclusion forming ability of cyclodextrins (CyD). Here, β-CyD was grafted to alginate in a three-step synthesis using periodate oxidation, reductive amination and copper(I)-catalyzed azide-alkyne cycloaddition.

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Purpose: The aim of this study is to test folate-conjugated cyclodextrin nanoparticles (FCD-1 and FCD-2) as a vehicle for reducing toxicity and increasing the antitumor efficacy of paclitaxel especially for metastatic breast cancer.

Methods: For the evaluation of PCX-loaded FCD nanoparticles, animal studies were realised in terms of survival rate, tumour size, weight change, metastazis and histopathological examination.

Results: FCD-1 displayed significant advantages such as efficient targeting of folate receptor positive breast cancer cells and having considerably lower toxicity compared to that of Cremophor.

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Recombinant antibody libraries can provide a source of renewable and high-performing binders tailored for use in affinity proteomics. In this context, the process of generating site-specific 1:1 tagging/functionalization and/or orientated surface immobilization of antibodies has, however, proved to be challenging. Hence, novel ways of generating such engineered antibodies for use in affinity proteomics could have a major impact on array performance.

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Host-guest nanoassemblies made from spontaneous self-association of host and guest polymers in aqueous solutions have been studied. The specific motivation behind this work was to clarify the impact of the molecular design of the polymers on the interactions between them and on the inner structure of the resulting nanoassemblies. The polymers were composed of a dextran backbone, functionalized with either pendant β-cyclodextrin (CD) or adamantyl (Ada).

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Real-time imaging was used to study the effects of a novel Fusarium-specific cyanoacrylate fungicide (JS399-19) on growth and morphology of four Fusarium sp. This fungicide targets the motor domain of type I myosin. Fusarium graminearum PH-1, Fusarium solani f.

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As nanomedicines are gaining momentum in the therapy of cancer, new biomaterials emerge as alternative platforms for the delivery of anticancer drugs with bioavailability problems. In this study, two novel amphiphilic cyclodextrins (FCD-1 and FCD-2) conjugated with folate group to enable active targeting to folate positive breast tumors were introduced. The objective of this study was to develop and characterize new folated-CD nanoparticles via 3(2) factorial design for optimal final parameters.

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The aim of this work was to investigate the suitability of β-cyclodextrin-dextran (BCD-dextran) polymer as cholesterol sequestering agent in vitro. For this purpose, BCD-dextran-cholesterol complexation was studied by phase solubility studies as well as with a specifically designed in vitro model based on giant unilamellar vesicles (GUVs) to evaluate the ability of this polymer to sequestrate cholesterol from phospholipid bilayers. Cholesterol-sequestering ability of BCD-dextran was also investigated on different cell lines relevant for the hematopoietic system and results were correlated to cells toxicity.

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The main goal of this work was to develop a supramolecular chemistry strategy to decorate interfaces with polyethylene glycol (PEG) grafts. A series of novel bifunctionalized dextrans, bearing 40-60 PEG pending chains and 12-24 hydrophobic adamantyl groups, have been prepared by copper(I)-catalyzed azide-alkyne cycloaddition. Their binding properties toward native βCD and βCD polymers were characterized both in solution and at interface using isothermal titration microcalorimetry and surface plasmon resonance.

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A novel β-cyclodextrin (β-CD) dimer was synthesized and surface-grafted by click chemistry onto azide-functionalized quartz surfaces in order to introduce the cooperative features of the β-CD dimer to solid surfaces. Using NMR and fluorescence spectroscopy, it is shown that the free β-CD dimer forms a 1:1 complex with the fluorescent guest molecule, 2-anilinonaphthalene-6-sulfonic acid (otherwise known not to form 1:2 complexes with parent β-CD), with an apparent association constant of 7300 M(-1). Further, it is shown using total internal reflection fluorescence spectroscopy that the inclusion of the fluorescent guest into both cavities of the β-CD dimer is maintained when grafted onto a solid surface.

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Novel (S)-camptothecin-dextran polymers were obtained by "click" grafting of azide-modified (S)-camptothecin and alkyne-modified dextrans. Two series based on 10 kDa and 70 kDa dextrans were prepared with a degree of substitution of (S)-camptothecin between 3.1 and 10.

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Polymeric β-cyclodextrin (βCD) films tunable with respect to thickness and βCD content were prepared in order to develop a suitable platform, allowing for inclusion of nonpolar guest molecules in the βCD cavity, while suppressing nonspecific protein adsorption. The βCD films were synthesized from linear βCD dextran polymers, and grafted onto silicon oxide surfaces by "click" chemistry. Topographic and morphological characteristics are controllable by reaction conditions and polymer type, with average film heights from 2.

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Polypropylene nonwovens were functionalised using a self-assembled, amphiphilic cyclodextrin coating and the potential for water purification by removal of pollutants was studied. As benzene is one of the problematic compounds in the Water Framework Directive, six volatile organic compounds (benzene and five benzene-based substances) were chosen as model compounds. The compounds were tested as a mixture in order to provide a more realistic situation since the wastewater will be a complex mixture containing multiple pollutants.

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Small carbon nano-onions (CNOs, 6-12 shells) were prepared in high yields and functionalized with carboxylic groups by chemical oxidation and reacted with βCD-NH2 to yield CNOs decorated with βCDs. A biocompatibile dextran polymer with graphted ferrocene groups was employed for the supramolecular self-assembly on the βCD-CNO surfaces. The βCDs act as hosts and the polymer ferrocene groups as guests (Fc-Dex) by the formation of inclusion complexes.

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Cyclodextrins and their water-soluble derivatives are excellent solubilizers and stabilizers and widely used as enabling pharmaceutical excipients. However, still new cyclodextrin derivatives are being designed and synthesized in an effort to improve their physicochemical properties. In this study physicochemical and self-associating characteristics of dextran-based cyclodextrin polymers, with ether or ester linkage between the β-cyclodextrin and the dextran backbone, were investigated.

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This study shows that diazotized β-cyclodextrin (β-CD) can be produced, isolated, and immobilized onto glassy carbon and gold surfaces. 4-(1,2,3-Triazol-4-yl)benzenediazonium-β-CD tetrafluoroborate (pDz-β-CD) and 3-(1,2,3-triazol-4-yl)benzenediazonium-β-CD tetrafluoroborate (mDz-β-CD) were successfully prepared by Cu((I))-catalyzed azide alkyne coupling (CuAAC) of 6-monodeoxy-6-monoazido-β-cyclodextrin (N(3)-β-CD) and 4-ethynylaniline and 3-ethynylaniline, respectively, followed by diazotization. The products were isolated and stored successfully for several months at -18 °C.

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Curcumin has been investigated as a potential photosensitizer (PS) in antimicrobial photodynamic therapy (aPDT). The phototoxic effect of curcumin is dependent on proper formulations of the compound because of the lipophilic nature of the molecule and the extremely low water solubility at physiological conditions. In the present study, the combination of curcumin with either a methylated β-cyclodextrin (CD) or polyethylene glycol-based β-CD or γ-CD polymers was investigated in aPDT using Escherichia coli (E.

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Nanoassemblies formed by host/guest interactions between two polymers in aqueous media are studied. Two types of polymers with the same dextran backbone are modified with adamantyl or βCD groups. The sizes of the spontaneously formed nanoassemblies depend on the βCD:Ada ratio and on the total concentration and composition of the mixtures.

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Three series of novel water-soluble beta-cyclodextrin-dextran polymers have been prepared by "click" chemistry. The polymers were synthesized from alkyne-modified dextrans (AMDs) onto which mono-6-O-deoxy-monoazido-betaCD (N3betaCD) was grafted by a copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The polymers have been characterized by NMR spectroscopy and size exclusion chromatography (SEC).

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