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Journal of Materials Chemistry. B Oct 2020Dynamic biochemical and biophysical signals of cellular matrix define and regulate tissue-specific cell functions and fate. To recapitulate this complex environment in... (Review)
Review
Dynamic biochemical and biophysical signals of cellular matrix define and regulate tissue-specific cell functions and fate. To recapitulate this complex environment in vitro, biomaterials based on structural- or degradation-tunable polymers have emerged as powerful platforms for regulating the "on-demand" cell-material dynamic interplay. As one of the most prevalent photoswitch molecules, the photoisomerization of azobenzene demonstrates a unique advantage in the construction of dynamic substrates. Moreover, the development of azobenzene-containing biomaterials is particularly helpful in elucidating cells that adapt to a dynamic microenvironment or integrate spatiotemporal variations of signals. Herein, this minireview, places emphasis on the research progress of azobenzene photoswitches in the dynamic regulation of matrix signals. Some techniques and material design methods have been discussed to provide some theoretical guidance for the rational and efficient design of azopolymer-based material platforms. In addition, considering that the UV-light response of traditional azobenzene photoswitches is not conducive to biological applications, we have summarized the recent approaches to red-shifting the light wavelength for azobenzene activation.
Topics: Animals; Azo Compounds; Cell Line, Tumor; Cellular Microenvironment; Coated Materials, Biocompatible; Electric Conductivity; Extracellular Matrix; Humans; Isomerism; Light; Polymers; Surface Properties
PubMed: 32929441
DOI: 10.1039/d0tb01737j -
Colloids and Surfaces. B, Biointerfaces Nov 2015Here, we have designed and synthesized a novel cationic amphiphilic stimuli-responsive azobenzene-aminoglycoside (a small molecule) conjugate, Azo-AG 5, and...
Here, we have designed and synthesized a novel cationic amphiphilic stimuli-responsive azobenzene-aminoglycoside (a small molecule) conjugate, Azo-AG 5, and characterized it by UV and FTIR. Light responsive nature of Azo-AG 5 was assessed under UV-vis light. Self- assembly of Azo-AG 5 in aqueous solutions into nanostructures and their ability to act as drug carrier were also investigated. The nanostructures of Azo-AG 5 showed average hydrodynamic diameter of ∼ 255 nm with aminoglycoside moiety (neomycin) and 4-dimethylaminoazobenzene forming hydrophilic shell and hydrophobic core, respectively. In the hydrophobic core, eosin and aspirin were successfully encapsulated. Dynamic light scattering (DLS) measurements demonstrated that the nanoassemblies showed expansion and contraction on successive UV and visible light irradiations exhibiting reversible on-off switch for controlling the drug release behavior. Similar behavior was observed when these nanostructures were subjected to pH-change. In vitro drug release studies showed a difference in UV and visible light-mediated release pattern. It was observed that the release rate under UV irradiation was comparatively higher than that observed under visible light. Further, azoreductase-mediated cleavage of the azo moiety in Azo-AG 5 nanoassemblies resulted in the dismantling of the structures into aggregated microstructures. Azo-AG 5 nanostructures having positive surface charge (+9.74 mV) successfully interacted with pDNA and retarded its mobility on agarose gel. Stimuli responsiveness of nanostructures and their on-off switch like behavior ensure the great potential as controlled drug delivery systems and in other biomedical applications such as colon-specific delivery and gene delivery.
Topics: Aminoglycosides; Azo Compounds; Cell Survival; DNA; Delayed-Action Preparations; Drug Carriers; Drug Delivery Systems; HeLa Cells; Humans; Hydrophobic and Hydrophilic Interactions; NADH, NADPH Oxidoreductases; Nanostructures; Nitroreductases; Photochemical Processes
PubMed: 26255160
DOI: 10.1016/j.colsurfb.2015.07.026 -
Molecules (Basel, Switzerland) Jun 2019The performance of 26 hybrid density functionals was tested against a tautomeric dataset (TautData), containing experimental information for the keto-enol tautomeric...
The performance of 26 hybrid density functionals was tested against a tautomeric dataset (TautData), containing experimental information for the keto-enol tautomeric equilibrium in 16 tautomeric azodyes and Schiff bases in cyclohexane, carbon tetrachloride and acetonitrile. The results have shown that MN12-SX, BHandH and M06-2X can be used to describe the tautomeric state of the core structures in the frame of ~0.5 kcal/mol error and correctly predict the tautomeric state in respect of dominating tautomeric form. Among them MN12-SX is the best performer, although it fails to describe the nonplanarity of some of the enol tautomers. The same experimental dataset was used to develop and test a special DFT functional (TautLYP) aimed at describing the tautomeric state in azo- and azomethyne compounds in solution when nonspecific solvents are used.
Topics: Algorithms; Azo Compounds; Coloring Agents; Models, Theoretical; Molecular Structure; Photochemical Processes; Spectrum Analysis; Stereoisomerism
PubMed: 31212924
DOI: 10.3390/molecules24122252 -
Environmental Science and Pollution... Aug 2016Increasing amount of dyes in an ecosystem has propelled the search of various methods for dye removal. Amongst all the methods, adsorption occupies a prominent place in... (Review)
Review
Increasing amount of dyes in an ecosystem has propelled the search of various methods for dye removal. Amongst all the methods, adsorption occupies a prominent place in dye removal. Keeping this in mind, many adsorbents used for the removal of hazardous anionic azo dye Congo red (CR) from aqueous medium were reviewed by the authors. The main objectives behind this review article are to assemble the information on scattered adsorbents and enlighten the wide range of potentially effective adsorbents for CR removal. Thus, CR sorption by various adsorbents such as activated carbon, non-conventional low-cost materials, nanomaterials, composites and nanocomposites are surveyed and critically reviewed as well as their sorption capacities are also compared. This review also explores the grey areas of the adsorption performance of various adsorbents with reference to the effects of pH, contact time, initial dye concentration and adsorbent dosage. The equilibrium adsorption isotherm, kinetic and thermodynamic data of different adsorbents used for CR removal were also analysed. It is evident from a literature survey of more than 290 published papers that nanoparticle and nanocomposite adsorbents have demonstrated outstanding adsorption capabilities for CR. Graphical abstract ᅟ.
Topics: Adsorption; Azo Compounds; Congo Red; Wastewater; Water Pollutants, Chemical; Water Purification
PubMed: 27255316
DOI: 10.1007/s11356-016-6970-0 -
Nature Communications Apr 2022Modifying the reactivity of substrates by encapsulation is essential for microenvironment catalysts. Herein, we report an alternative strategy that modifies the entry...
Modifying the reactivity of substrates by encapsulation is essential for microenvironment catalysts. Herein, we report an alternative strategy that modifies the entry behaviour of reactants into the microenvironment and substrate inclusion thermodynamics related to the capsule to control the electron injection kinetics and the selectivity of products from the nitroarenes photoreduction. The strategy includes the orchestration of capsule openings to control the electron injection kinetics of electron donors, and the capsule's pocket to encapsulate more than one nitroarene molecules, facilitating a condensation reaction between the in situ formed azanol and nitroso species to produce azo product. The conceptual microenvironment catalyst endows selective conversion of asymmetric azo products from different nitroarenes, wherein, the estimated diameter and inclusion Gibbs free energy of substrates are used to control and predict the selectivity of products. Inhibition experiments confirm a typical enzymatic conversion, paving a new avenue for rational design of photocatalysts toward green chemistry.
Topics: Azo Compounds; Catalysis; Electrons; Kinetics; Thermodynamics
PubMed: 35410425
DOI: 10.1038/s41467-022-29559-z -
European Journal of Medicinal Chemistry Jan 2018Colchicine analogues in which an azo group is incorporated into a molecule containing the key pharmacophore of colchicine, have found particular utility as switchable...
Colchicine analogues in which an azo group is incorporated into a molecule containing the key pharmacophore of colchicine, have found particular utility as switchable tubulin binding chemotherapeutics. Combretastatin is a related compound containing a stilbene fragment that shows different bioactivity for the cis and trans isomers. We have performed cell assays on 17 new compounds structurally related to a previously reported azo-analogue of combretastatin. One of these compounds showed enhanced potency against HeLa (IC = 0.11 μM) and H157 cells (IC = 0.20 μM) for cell studies under 400 nm irradiation and the highest photoactivity (IC with irradiation/IC in dark = 550). We have performed docking and physicochemical studies of this new compound (7). Kinetic studies in water reveal a longer half-life for the cis isomer of 7 which may be one factor responsible for the better IC values in cell assays and the improved photoresponsive behavior.
Topics: Antineoplastic Agents; Azo Compounds; Cell Proliferation; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Kinetics; Ligands; Molecular Structure; Photochemical Processes; Stilbenes; Structure-Activity Relationship; Ultraviolet Rays
PubMed: 29172077
DOI: 10.1016/j.ejmech.2017.11.012 -
Journal of Medicinal Chemistry Oct 2020Photopharmacology is a growing area of endeavor that employs photoswitchable ligands to allow for light-dependent pharmacological activity. By coupling light to... (Review)
Review
Photopharmacology is a growing area of endeavor that employs photoswitchable ligands to allow for light-dependent pharmacological activity. By coupling light to therapeutic action, improved spatial and temporal selectivity can be achieved and subsequently harnessed for new concepts in therapy. Tremendous progress has already been made, with photopharmacological agents now reported against a wide array of target classes and light-dependent results demonstrated in a range of live cell and animal models. Several challenges remain, however, especially in order for photopharmacology to truly impact the clinical management of disease. This Perspective aims to summarize these challenges, particularly with attention to the medicinal chemistry that will be unavoidably required for the further translation of these agents/approaches. By clearly defining challenges for drug hunters, it is hoped that further research into the medicinal chemistry of photopharmacological agents will be stimulated, ultimately enabling full realization of the huge potential for this exciting field.
Topics: Animals; Azo Compounds; Drug Discovery; Humans; Ligands; Light; Molecular Structure; Pharmaceutical Preparations; Photochemical Processes; Photochemotherapy; Photosensitizing Agents; Small Molecule Libraries
PubMed: 32511922
DOI: 10.1021/acs.jmedchem.0c00629 -
Journal of the American Chemical Society Jan 2023Photoresponsive inhibitor and noninhibitor systems have been developed to achieve on-demand enzyme activity control. However, inhibitors are only effective for a...
Photoresponsive inhibitor and noninhibitor systems have been developed to achieve on-demand enzyme activity control. However, inhibitors are only effective for a specific and narrow range of enzymes. Noninhibitor systems usually require mutation and modification of the enzymes, leading to irreversible loss of enzymatic activities. Inspired by biological membranes, we herein report a lipidoid-based artificial compartment composed of azobenzene (Azo) lipidoids and helper lipids, which can bidirectionally regulate the activity of the encapsulated enzymes by light. In this system, the reversible photoisomerization of Azo lipidoids triggered by UV/vis light creates a continuous rotation-inversion movement, thereby enhancing the permeability of the compartment membrane and allowing substrates to pass through. Moreover, the membrane can revert to its impermeable state when light is removed. Thus, enzyme activity can be switched on and off when encapsulating enzymes in the compartments. Importantly, since neither mutation nor modification is required, negligible loss of activity is observed for the encapsulated enzymes after repeated activation and inhibition. Furthermore, this approach provides a generic strategy for controlling multiple enzymes by forgoing the use of inhibitors and may broaden the applications of enzymes in biological mechanism research and precision medicine.
Topics: Ultraviolet Rays; Cell Membrane; Azo Compounds
PubMed: 36537880
DOI: 10.1021/jacs.2c11004 -
Chemical & Pharmaceutical Bulletin 2021The ability to control the reactions of highly active chemical species to enable straightforward synthesis of valuable compounds such as bioactive natural products and... (Review)
Review
The ability to control the reactions of highly active chemical species to enable straightforward synthesis of valuable compounds such as bioactive natural products and pharmaceuticals is a continuing challenge in synthetic organic chemistry. This review describes the development of a methodology using reactive metal-carbene species and its synthetic application in our laboratory. First, regioselective synthesis of γ-amino acid equivalents to take advantage of their metal-dependent reactivities and the mechanistic rationale are presented. Chemoselective and enantioselective dearomatization reactions of several arenes with silver-carbene are also discussed. In the second half of the review, we discuss a carbene-insertion reaction into an amide and urea C-N bond for the assembly of nitrogen-bridged cyclic molecules.
Topics: Azo Compounds; Catalysis; Metals, Heavy; Methane
PubMed: 34853283
DOI: 10.1248/cpb.c21-00757 -
Chemosphere May 2022Azo dyes are typical toxic and refractory organic pollutants widely used in the textile industry. Bio-electrochemical systems (BESs) have great potential for the... (Review)
Review
Azo dyes are typical toxic and refractory organic pollutants widely used in the textile industry. Bio-electrochemical systems (BESs) have great potential for the treatment of azo dyes with the help of microorganisms as biocatalysts and have advanced significantly in recent years. However, the latest and significant advancement and achievements of BESs treating azo dyes have not been reviewed since 8 years ago. This review thus focuses on the recent investigations of BESs treating azo dyes from the year of 2013-2020 in order to broaden the knowledge and deepen the understanding in this field. In this review, azo dyes degradation mechanisms of BESs are first elaborated, followed by the introduction of BES configurations with the emphasis on the novelties. The azo dye degradation performance of BESs is then presented to demonstrate their effectiveness in azo dye removal. Effects of various operating parameters on the overall performance of BESs are comprehensively elucidated, including electrode materials, external resistances and applied potentials, initial concentrations of azo dyes, and co-substrates. Predominant microorganisms responsible for degradation of azo dyes in BESs are highlighted in details. Furthermore, the combination of BESs with other processes to further improve the azo dye removal are discussed. Finally, an outlook on the future research directions and challenges is provided from the viewpoint of realistic applications of the technology.
Topics: Azo Compounds; Coloring Agents; Electrodes; Textile Industry; Wastewater
PubMed: 35104551
DOI: 10.1016/j.chemosphere.2022.133801