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1.
J Inflamm Res ; 17: 865-880, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348276

RESUMO

Purpose: The purpose of this study was to analyze the nasal lymphatic system in order to uncover novel factors that might be involved in pathogenesis of chronic rhinosinusitis (CRS) with (CRSwNP) and without nasal polyps (CRSsNP). Patients and Methods: Lymphatic vessels (LVs) and macrophages were localized and counted in the inferior and middle turbinate, the uncinate process and the ethmoid of CRSwNP and CRSsNP patients, the NP and the inferior turbinate of controls (n≥6 per group). Lysates of the same tissue types (n=7 per group) were analyzed for lymphatic vessel endothelial receptor 1 (LYVE-1), for matrix metalloproteinase 14 (MMP-14) and for Hyaluronic acid (HA) using ELISA. HA was localized in sections of CRSwNP NP, CRSsNP ethmoid and control inferior turbinate (n=6 per group). The results of HA levels were correlated to the number of macrophages in tissues. The nasal secretions of CRSwNP (n=28), CRSsNP (n=30), and control (n=30) patients were analyzed for LYVE-1 and HA using ELISA. Results: The number of LVs was significantly lower in tissues of both CRS groups compared to the control. In the tissue lysates, LYVE-1 expression differed significantly between the CRSwNP tissues with a particularly high level in the NP. MMP-14 was significantly overexpressed in CRSwNP uncinate process. There were no significant differences in tissue HA expression. In the mucus LYVE-1 was significantly underexpressed in CRSsNP compared to CRSwNP and control, while HA was significantly underexpressed in both CRS groups. In the NP, HA and macrophages were accumulated particularly below the epithelium. Tissue levels of HA revealed a significant positive correlation with the number of macrophages. Conclusion: CRS might be associated with an insufficient clearing of the nasal mucosa through the lymphatics. The accumulation of HA and macrophages might promote inflammation, fluid retention, and polyp formation. These results may provide novel CRS-associated factors.

2.
Nanoscale ; 16(2): 923-940, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38108137

RESUMO

Electrostatic self-assembly of photoacids with oppositely charged macroions yields supramolecular nano-objects in aqueous solutions, whose size is controlled through light irradiation. Nano-assemblies are formed due to electrostatic attractions and mutual hydrogen bonding of the photoacids. Irradiation with UV light leads to the deprotonation of the photoacid and, consequently, a change in particle size. Overall, the hydrodynamic radii of the well-defined photoacid-macroion nano-objects lie between 130 and 370 nm. For a set of photoacids, we determine the acidity constants in the ground and excited state, discuss the sizes of photoacid-macroion nano-objects (by dynamic and static light scattering), their composition and the particle shapes (by small-angle neutron scattering), and relate their charge characteristics to size, structure and shape. We investigate the association thermodynamics and relate nanoscale structures to thermodynamics and, in turn, thermodynamics to molecular features, particularly the ionization energy of the photoacid hydroxyl group proton. Structure-directing effects completely differ from those for previously investigated systems, with hydrogen bonding and entropic effects playing a major role herein. This combined approach allows developing a comprehensive understanding of assembly formation and photo-response, anchored in molecular parameters (pKa, ionization energy, substituent group location), charge characteristics, and the association enthalpy and entropy. This fundamental understanding again paves the way for tailoring application solutions with novel photoresponsive materials.

3.
J Phys Chem Lett ; 14(43): 9563-9568, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37861686

RESUMO

Quadruple-switchable nanoscale assemblies are built by combining two types of water-soluble molecular photoswitches through dipole-dipole interaction. Uniting the wavelength-specific proton dissociation of a photoacid and ring-opening of an anionic spirooxazine results in an assembly that can be addressed by irradiation with two different wavelengths: pH and darkness.

4.
Langmuir ; 39(30): 10312-10320, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37462454

RESUMO

Using electrostatic self-assembly and electrostatic nanotemplating, a quaternary nanostructured system consisting of zinc oxide nanoparticles, gold nanoparticles, poly[3-(potassium-4-butanoate)thiophene-2,5-diyl] (PT), and methyltrioctylammonium chloride (MTOA) (PT-MTOA-ZnO-Au) was designed for aqueous photocatalysis. The PT-MTOA hollow sphere aggregates served as an electrostatic template for both individual inorganic nanoparticles controlling their morphology, stabilizing the nanoparticles, and acting as a photosensitizer. The hybrid structures included spherical ZnO nanoparticles with a diameter of d = 2.6 nm and spherical Au nanoparticles with d = 6.0 nm embedded in PT-MTOA hollow spheres with a hydrodynamic radius of RH = 100 nm. The ZnO nanoparticles acted as the main catalyst, while the Au nanoparticles acted as the cocatalyst. As a photocatalytic model reaction, the dye degradation of methylene blue in aqueous solution using the full spectral range from UV to visible light was tested. The photocatalytic activity was optimized by varying the Zn and Au loading ratios and was substantially enhanced regarding the components; for example, it was increased by about 61% using PT-MTOA-ZnO-Au compared to the composite without gold particles. A photocatalytic mechanism of the methylene blue degradation was proposed when catalyzed by these multicomponent nano-objects. Thus, a simple procedure of templating two different nanoparticle species within the same cocatalytically active template has been demonstrated, which can be extended to other inorganic particles, making a variety of task-specific catalysts accessible.

5.
Chemistry ; 29(10): e202203373, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36336659

RESUMO

Multi-switchable supramolecular nano-objects that respond to irradiation of different wavelengths with changes in size and shape have been built from two different water-soluble molecular switches, joined by attachment to the same polyelectrolyte. Accordingly, two wavelength-specific reactions, namely the excited-state proton dissociation of a photoacid and the cis-trans isomerization of an azo dye, are combined in one supramolecular nano-object that is stable in aqueous solution. The concept has potential in the fields of sensors, molecular motors, and transport.

6.
Am J Rhinol Allergy ; 37(3): 348-359, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36341722

RESUMO

BACKGROUND: Chronic rhinosinusitis without nasal polyps (CRSsNP) represents a phenotype of CRS, whose immunological mechanisms are still unclear. So far there are neither suitable biomarkers to determine the course of the disease nor an individual therapy. OBJECTIVE: The purpose of this study was to characterize the CRSsNP endotype by identifying and validating non-invasive proteomic biomarkers. METHODS: A highly-multiplexed proteomic array consisting of antibodies against 2000 proteins was used to identify proteins that are differentially expressed in the nasal mucus of the CRSsNP and control groups (n = 7 per group). The proteins identified to be most differentially expressed were validated in matched nasal mucus samples using western blots and enzyme-linked immunosorbent assay (ELISA). Validation was also done in a second cohort using western blots (CRSsNP n = 25, control n = 23) and ELISA (n = 30 per group). Additionally, immunohistochemistry in CRSsNP and control tissue samples was performed to characterize the selected proteins further. RESULTS: Out of the 2000 proteins examined, 7 from the most differentially expressed proteins were chosen to be validated. The validation results showed that 4 proteins were significantly upregulated in CRSsNP mucus, including macrophage inflammatory protein-1beta (MIP-1ß), resistin, high mobility group box 1 (HMGB1), and forkhead box protein 3 (FOXP3). Cartilage acidic protein 1 (CRTAC1) was not significantly upregulated. Two proteins were significantly downregulated including scavenger receptor class F member 2 (SCARF2) and P-selectin. All proteins selected are mainly associated with inflammation, cell proliferation/differentiation, apoptosis and cell-cell or cell-matrix interaction. CONCLUSION: Proteomic analysis of CRSsNP and control mucus has confirmed known and revealed novel disease-associated proteins that could potentially serve as a new biosignature for CRSsNP. Analysis of the associated pathways will specify endotypes of CRSsNP and will lead to an improved understanding of the pathophysiology of CRSsNP. Furthermore, our data contribute to the development of a reproducible, non-invasive, and quantitative "liquid biopsy" for rhinosinusitis.


Assuntos
Pólipos Nasais , Rinite , Sinusite , Humanos , Proteoma/metabolismo , Proteômica , Muco/metabolismo , Biomarcadores , Doença Crônica , Proteínas de Ligação ao Cálcio
7.
Polymers (Basel) ; 16(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38201714

RESUMO

Electrostatic self-assembly of macroions is an emerging area with great potential in the development of nanoscale functional objects, where photo-irradiation responsiveness can either elevate or suppress the self-assembly. The ability to control the size and shape of macroion assemblies would greatly facilitate the fabrication of desired nano-objects that can be harnessed in various applications such as catalysis, drug delivery, bio-sensors, and actuators. Here, we demonstrate that a polyelectrolyte with a size of 5 nm and multivalent counterions with a size of 1 nm can produce well-defined nanostructures ranging in size from 10-1000 nm in an aqueous environment by utilizing the concept of electrostatic self-assembly and other intermolecular non-covalent interactions including dipole-dipole interactions. The pH- and photoresponsiveness of polyelectrolytes and azo dyes provide diverse parameters to tune the nanostructures. Our findings demonstrate a facile approach to fabricating and manipulating self-assembled nanoparticles using light and neutron scattering techniques.

8.
Nanoscale ; 14(36): 13040-13045, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-35912789

RESUMO

We demonstrate a versatile route to functional multi-component nanostructures by a hierarchical electrostatic nanotemplating - self-assembly approach: CdS-polyelectrolyte-porphyrin structures are formed in aqueous solution. The system was investigated with regard to its photocatalytic activity in different model reactions, and the mechanisms upon excitation were elucidated.

9.
Chemistry ; 27(32): 8380-8389, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-33871113

RESUMO

A protecting group strategy was employed to synthesise a series of indolenine squaraine dye oligomers up to the nonamer. The longer oligomers show a distinct solvent dependence of the absorption spectra, that is, either a strong blue shift or a strong red shift of the lowest energy bands in the near infrared spectral region. This behaviour is explained by exciton coupling theory as being due to H- or J-type coupling of transition moments. The H-type coupling is a consequence of a helix folding in solvents with a small Hansen dispersity index. DOSY NMR, small angle neutron scattering (SANS), quantum chemical and force field calculations agree upon a helix structure with an unusually large pitch and open voids that are filled with solvent molecules, thereby forming a kind of clathrate. The thermodynamic parameters of the folding process were determined by temperature dependent optical absorption spectra.

10.
Beilstein J Org Chem ; 17: 166-185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33564327

RESUMO

Light- and pH-responsive nano-assemblies with switchable size and structure are formed by the association of a photoacid, anthocyanidin, and a linear polyelectrolyte in aqueous solution. Specifically, anionic disulfonated naphthol derivatives, neutral hydroxyflavylium, and cationic poly(allylamine) are used as building blocks for the ternary electrostatic self-assembly, forming well-defined supramolecular assemblies with tunable sizes of 50 to 500 nm. Due to the network of possible chemical reactions for the anthocyanidin and the excited-state dissociation of the photoacid upon irradiation, different ways to alter the ternary system through external triggering are accessible. The structure and trigger effects can be controlled through the component ratios of the samples. Dynamic and static light scattering (DLS, SLS) and ζ-potential measurements were applied to study the size and the stability of the particles, and information on the molecular structure was gained by UV-vis spectroscopy. Isothermal titration calorimetry (ITC) provided information on the thermodynamics and interaction forces in the supramolecular assembly formation.

11.
Front Chem ; 9: 779360, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35359487

RESUMO

The design of functional nano-objects by electrostatic self-assembly in solution signifies an emerging field with great potential. More specifically, the targeted combination of electrostatic interaction with other effects and interactions, such as the positioning of charges on stiff building blocks, the use of additional amphiphilic, π-π stacking building blocks, or polyelectrolytes with certain architectures, have recently promulgated electrostatic self-assembly to a principle for versatile defined structure formation. A large variety of architectures from spheres over rods and hollow spheres to networks in the size range of a few tenths to a few hundred nanometers can be formed. This review discusses the state-of-the-art of different approaches of nano-object formation by electrostatic self-assembly against the backdrop of corresponding solid materials and assemblies formed by other non-covalent interactions. In this regard, particularly promising is the facile formation of triggerable structures, i.e. size and shape switching through light, as well as the use of electrostatically assembled nano-objects for improved photocatalysis and the possible solar energy conversion in the future. Lately, this new field is eliciting an increasing amount of understanding; insights and limitations thereof are addressed in this article. Special emphasis is placed on the interconnection of molecular building block structures and the resulting nanoscale architecture via the key of thermodynamics.

12.
Polymers (Basel) ; 12(8)2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32764323

RESUMO

In this study, light-responsive nano-assemblies with light-switchable size based on photoacids are presented. Anionic disulfonated napthol derivates and cationic dendrimer macroions are used as building blocks for electrostatic self-assembly. Nanoparticles are already formed under the exclusion of light as a result of electrostatic interactions. Upon photoexcitation, an excited-state dissociation of the photoacidic hydroxyl group takes place, which leads to a more highly charged linker molecule and, subsequently, to a change in size and structure of the nano-assemblies. The effects of the charge ratio and the concentration on the stability have been examined with absorption spectroscopy and ζ-potential measurements. The influence of the chemical structure of three isomeric photoacids on the size and shape of the nanoscale aggregates has been studied by dynamic light scattering and atomic force microscopy, revealing a direct correlation of the strength of the photoacid with the changes of the assemblies upon irradiation.

13.
Angew Chem Int Ed Engl ; 59(42): 18786-18794, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-32652750

RESUMO

In the scientific race to build up photoactive electron donor-acceptor systems with increasing efficiencies, little is known about the interplay of their building blocks when integrated into supramolecular nanoscale arrays, particularly in aqueous environments. Here, we describe an aqueous donor-acceptor ensemble whose emergence as a nanoscale material renders it remarkably stable and efficient. We have focused on a tetracationic zinc phthalocyanine (ZnPc) featuring pyrenes, which shows an unprecedented mode of aggregation, driven by subtle cooperation between electrostatic and π-π interactions. Our studies demonstrate monocrystalline growth in solution and a symmetry-breaking intermolecular charge transfer between adjacent ZnPcs upon photoexcitation. Immobilizing a negatively charged fullerene (C60 ) as electron acceptor onto the monocrystalline ZnPc assemblies was found to enhance the overall stability, and to suppress the energy-wasting charge recombination found in the absence of C60 . Overall, the resulting artificial photosynthetic model system exhibits a high degree of preorganization, which facilitates efficient charge separation and subsequent charge transport.

14.
Angew Chem Int Ed Engl ; 59(37): 16233-16240, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32472586

RESUMO

We report on the impact of the central heteroatom on structural, electronic, and spectroscopic properties of a series of spirofluorene-bridged heterotriangulenes and provide a detailed study on their aggregates. The in-depth analysis of their molecular structure by NMR spectroscopy and X-ray crystallography was further complemented by density functional theory calculations. With the aid of extensive photophysical analysis the complex fluorescence spectra were deconvoluted showing contributions from the peripheral fluorenes and the heteroaromatic cores. Beyond the molecular scale, we examined the aggregation behavior of these heterotriangulenes in THF/H2 O mixtures and analyzed the aggregates by static and dynamic light scattering. The excited-state interactions within the aggregates were found to be similar to those found in the solid state. A plethora of morphologies and superstructures were observed by scanning electron microscopy of drop-casted dispersions.

15.
Biomacromolecules ; 20(2): 979-991, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30570257

RESUMO

Novel light-responsive nanoassemblies with switchable size and enzymatic activity are built from a protein and a water-soluble spiropyran. Assemblies are created by electrostatic self-assembly in aqueous solution such that the photochromic property of the spiropyran enables light responsiveness. Upon visible light exposure, the aggregate size increases from 200 to 400 nm. The enzyme retains its activity upon aggregation into the assembly, while it decreases through visible light irradiation. Fundamentally, we show how the two different spiropyran isomers, the open-ring merocyanine form and the closed-ring spiropyran form, bind differently to the protein, which triggers the assembly size and use of thermodynamic data to understand the binding process and the size response. Thus, as a proof of concept, a self-assembly driven light-tunable enzyme activity in conjunction with a triggerable assembly size is demonstrated for a model system. The concept bears future potential for various possible biological applications ranging from genetic control over vaccine applications to the detection of certain proteins.


Assuntos
Benzopiranos/química , Indóis/química , Muramidase/química , Nanopartículas/química , Nitrocompostos/química , Luz , Termodinâmica
16.
Chem Commun (Camb) ; 54(82): 11642-11644, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30272065

RESUMO

We present charge-transfer assemblies of electron accepting, pressure-synthesized carbon nanodots (pCNDs) and an electron donating porphyrin. Amidine derivatization of the porphyrin allows for hydrogen bonding interactions with the carboxyl groups on the surface of pCNDs, which drive the formation of the assembly. Upon photoexcitation, this electron donor-acceptor supramolecular construct features ultrafast charge separation, and subsequent charge recombination in 27 ps.

17.
Macromol Rapid Commun ; 39(17): e1700860, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29504172

RESUMO

A light-triggered shape change of supramolecular nanostructures is achieved through electrostatically self-assembly of linear polyelectrolytes and oppositely charged dyes in aqueous solution: Upon UV-irradiation, 1-µm-long, flexible cylinders with a cross-section of 10 nm convert into ellipsoids of 400 nm × 40 nm. The nano-object shape is encoded in the molecular dye structure.


Assuntos
Corantes/síntese química , Nanoestruturas/química , Polímeros/síntese química , Raios Ultravioleta , Corantes/química , Eletrólitos/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Estrutura Molecular , Tamanho da Partícula , Polímeros/química , Eletricidade Estática
18.
Macromol Rapid Commun ; 38(17)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28727193

RESUMO

In this study, a new type of functional, self-assembled nanostructure formed from porphyrins and polyamidoamine dendrimers based on hydrogen bonding in an aqueous solution is presented. As the aggregates formed are promising candidates for solar-energy conversion, their photocatalytic activity is tested using the model reaction of methyl viologen reduction. The self-assembled structures show significantly increased activity as compared to unassociated porphyrins. Details of interaction forces driving the supramolecular structure formation and regulating catalytic efficiency are fundamentally discussed.


Assuntos
Luz , Polímeros/química , Porfirinas/química , Energia Solar , Água/química , Ligação de Hidrogênio
19.
Sci Rep ; 7: 44115, 2017 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-28327560

RESUMO

Biomass waste products from green algae have recently been given new life, as these polysaccharides have potential applications in industry, agriculture, and medicine. One such polysaccharide group called ulvans displays many different, potentially useful properties that arise from their structural versatility. Hence, performing structural analyses on ulvan is crucial for future applications. However, chemical reaction-based analysis methods cannot fully characterize ulvan and tend to alter its structure. Thus, better methods require well-characterized ulvan-degrading enzymes. Therefore, we analysed a previously sequenced ulvan lyase (GenebankTM reference number JN104480) and characterized its domains. We suggest that the enzyme consists of a shorter than previously described catalytic domain, a newly identified substrate binding domain, and a C-terminal type 9 secretion system signal peptide. By separately expressing the two domains in E. coli, we confirmed that the binding domain is ulvan specific, having higher affinity for ulvan than most lectins for their ligands (affinity constant: 105 M-1). To our knowledge, this is the first description of an ulvan-binding domain. Overall, identifying this new binding domain is one step towards engineering ulvan enzymes that can be used to characterize ulvan, e.g. through enzymatic/mass spectrometric fingerprinting analyses, and help unlock its full potential.


Assuntos
Domínio Catalítico , Polissacarídeo-Liases/metabolismo , Clorófitas/química , Escherichia coli , Polissacarídeo-Liases/química , Polissacarídeo-Liases/isolamento & purificação , Ligação Proteica , Especificidade por Substrato
20.
Chemistry ; 23(26): 6249-6254, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28299870

RESUMO

Combining chemically different building blocks in supramolecular nanoparticles is a promising key to tailored structures and functionalities. π-π heterostacks of dye molecules form upon electrostatic self-assembly with a polyelectrolyte, resulting in stable ternary nano-assemblies in aqueous solution. Core-shell spheres, cylinders, and flexible cylinders result, which exhibit new shapes different from the binary systems. Particle shapes can be tuned through the dye composition.

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