Diego Navarro-BarredaBegona BedrinaCesar A.Angulo-Pachon
8页
查看更多>>摘要：Four new BODIPY derivatives with a potential tendency to aggregation have been synthesized and characterized by means of NMR techniques,mass spectrometry and UV-Vis/fluorescence spectroscopies.The objective of this study is to determine which structural factors of the new molecules influence most notably the cellular uptake,intracellular location and fluorescence imaging abilities.The behaviour of the compounds in organic solvent and aqueous solution has been studied.In organic solvents(DMSO,ethanol and toluene),the photophysical prop-erties of the new molecules are almost independent of the building blocks used to synthesize the pendant moieties(non-fluorogenic parts).In an aqueous environment(HEPES Buffer Solution,pH 7),at 10 μM,three of the compounds(1,2 and 4)tend to form weakly emissive nanoparticles(DLS determination)whereas one of them(3)remains soluble and highly fluorescent.In the nanomolar range of concentration,all the compounds are aqueous soluble.The cellular internalisation of the compounds(10 nM)has been studied in human colon adenocarcinoma HT-29 cells by means of flow cytometry and confocal laser scanning microscopy.All the compounds were uptaken by HT-29 cells,but notably molecule 3(made with lysine as a building block)was the one displaying a higher loading and a more clear lysosomal location(0.88 Pearson's correlation coefficient in colocalization assays using lysosomal fluorescent probe LysoTracker DND-99).Molecule 3 also performed better than the valine derivative 1 as a lysosomal marker in a cellular model(human adrenal carcinoma SW13/cl.2 cells)of lysosomal storage disease(Niemann-Pick type C).
查看更多>>摘要：A group of new disperse dyes containing urea groups was synthesized by coupling various diazonium salt with urea-containing coupling components,which were prepared by the reaction between N-(2-Aminoethyl)-N-ethyl-3-methylbenzenamine and p-toluene isocyanate.Then,the structures of the synthesized dyes were characterized by ~1H NMR,~(13)C NMR,FTIR,and MS analysis.The spectral characteristics of the dimethylformamide(DMF)solution and applied properties on the nylon fabric for all of the new dyes were assessed and compared with the amino-containing control dye.Correlations between molecular structure and dyeing properties on nylon fabric for the urea-containing dyes were investigated by using density functional theory(DFT).The results indicated that the dyeing rates of the dyes became slower,and the fastness properties on the nylon fibers,including washing,sublimation,and light,were greatly improved after the introduction of the p-toluenpiride group.The color performance,build-up,and light fastness properties of the urea-containing dyes varied with the diazo components,among which 4-nitroaniline and its cyano substituted analogues performed well.Both dye exhaustion and saturation adsorption on the nylon fabric were negatively correlated with the product(F2.F6)of the dipole moment of the dye(F2)and its molecular weight(F6).In addition,the ClogP value had a significant!negative correlation with the washing change fastness,and the dipole moment of the dye was positively correlated with the sublimation change fastness.Also,the dyes with larger molecular volume and molecular weight had lower rates of sublimation changes and wet crocking fastness due to surface adsorption on the nylon fibers.
查看更多>>摘要：Chlorins belong to a group of photosensitizers that are significant and promising for photodynamic therapy(PDT).The newly synthesized oxospirochlorins presented in this study revealed an outstanding ability to generate singlet oxygen and high photostability.The obtained porphyrinoids were incorporated into liposomes,and then their antimicrobial activity against priority pathogens:MRSA,E.coli(ESBL+),and fluconazole-resistant C.albicans was examined.The excellent activity against both Gram-positive and Gram-negative bacteria was observed.Moreover,the synergism between sublethal antibacterial PDT and antibiotics with limited efficacy against resistant strains was investigated.As a result of the photodynamic activity of chlorins,it was possible to partially restore the sensitivity of bacteria to antibiotics from the group of cephalosporins and carbapenems.
查看更多>>摘要：The solid-liquid phase transition of adhesives triggered by two different wavelength light stimuli enables the switchable and reusable character.The adhesive which could be liquified by photothermal effect by single-wavelength light stimulus and solidified by natural cooling is much easier to operate but little developed.In this work,a class of tropinone-based enone dyes(TPs),prepared by one-pot Claisen-Schmidt condensation,were explored as a novel kind of single-wavelength light-switchable adhesives.TPs could absorption visible light and are non-fluorescent.By changing the length of alkoxy groups,the melting point and crystallization behavior were regulated.Especially,TP6 and TP8 could form overcooled liquid during the cooling process,thus enabling a proper adhesion operation window.Under 405 nm LED irradiation,the rapid solid-liquid transformation was achieved for some of TPs due to the high thermal conversion ability.TPs presented good adhesion strength toward glass plates.Among them,TP8 could work as a reusable and light-switchable adhesive.
查看更多>>摘要：Research into waterborne coatings is growing at an unprecedented rate in the world.To solve the problem of stabilizing pigments in aqueous system,we have encapsulated pigment yellow 155(PY155)with poly(methyl methacrylate-co-butyl acrylate),denoted as PY@P(MMA-co-BA).Breeding of bacteria is another adverse factor that deteriorates the function of waterborne coatings.Further grafting of brush-like poly(methyl hydroxyethyl acrylate)(PHEAA)could give the particle a structural antibacterial function,denoted as PY@P(MMA-co-BA)PHEAA,which exceeds the addition of antibacterial agent,as well as a better dispersity.The composite particle PY@P(MMA-co-BA)PHEAA overcomes the problems of adding extra antimicrobial agents and dispersants.The effects of monomer type and ratio,emulsifier type and amount,and the amount of HEAA on the composite particles preparation were investigated,along with the centrifugal stability,pH stability,and electrolyte stability of PY@P(MMA-co-BA)and PY@P(MMA-co-BA)@PHEAA.Finally,antibacterial property were carried out which demonstrated the excellent antibacterial property of the prepared PY@P(MMA-co-BA)@PHEAA composite particles.
查看更多>>摘要：Herein,based on 1,8-naphtholactam,we have developed twisted and conjugated fluorophores,NPM-1 and NPM-2,which featured efficient emissions in both dispersion and aggregation states with quantum yields up to 0.76 and 0.84,respectively.From spectral and density functional theory(DFT)calculation,the luminescence mechanism of both compounds was intramolecular charge transfer(ICT)in this D-A type molecules,and the structural differences lead to differences in the intensity of ICT effects.Moreover,NPM-1 exhibited efficient and stable emissions in a variety of environments due to its rational structural design.It was a sensitive lysosome-targeting dye and retains its fluorescence intensity under continuous laser irradiation.All these features made it an unprecedented chemical tool for real-time monitoring of lysosomal status and changes,leading to a better understanding of physiological and pathological processes.
查看更多>>摘要：In this work,a novel type of vesicles(Vt/g)composed of Gemini cationic surfactant(G12-8-12)and TPE-20H,an AIEgen fluorescence probe,were prepared by methanol evaporation method.Herein,G12-8-12 has good bacteriostatic function.TPE-20H with aggregation-induced emission feature resided in the interlayer of V_(T/G).The average size of V_(T/G)was about 1.2-1.4 pm measured by dynamic light scattering.Zeta potential studies indicated that V_(T/G)could bind to bacteria like S.aureus and E.coli under electrostatic interaction,increasing the size of the complex of Vt/g and bacteria to 4.5-6 μm.Because Vt/g interlayer was compressed by external bacteria,the aggregation degree of TPE-20H was increased,and the fluorescence intensity was increased by 3 times compared with Vt/g alone.The linear increase in fluorescence intensity with the increase of bacteria content implied that it is possible to sense bacteria.After the bacteria were co-incubated with Vt/g,almost no bacteria growth was observed with the light irradiation for 30 min,indicating that V_(T/G)showed good bactericidal effect.This can be ascribed to the synergistic effect of the inherent bactericidal property of G12-8-12 and the oxygen-active substances generated from TPE-20H.This new strategy integrating bacteria detection and killing showed good potential application.
查看更多>>摘要：In the present protocol,a series of varyingly substituted terpyridine-based ligands have been designed and synthesized through a well-known Krohnke reaction.Their binding behavior was evaluated with the library of metal cations.Their complexation with Ru(II),Fe(II),Co(II)and Zn(II)led to interesting coordination compounds with fascinating spectroscopic and electrochemical properties.The structural elucidation of all the newly synthesized ligands was accomplished by UV-Vis,FT-IR and ~1H and ~(13)C NMR spectroscopic techniques and the complexes were characterized by UV-Vis,FT-IR,~1H and ~(13)C NMR and MALDI-TOF mass spectrometry.Their absorption behavior in dilute solutions was investigated in order to elucidate the structure-property relationship and demonstrate the effect of the nature of different aryl-substituents on the terpyridine scaffold as well as a decisive role of metal on the complexes.Likewise,the electrochemical behavior of these complexes(C1-C9)at a platinum electrode was analyzed by cyclic voltammetry and investigated at 200,100 and 40 mVs~(-1)in aceto-nitrile(CH3CN).These complexes showed a quasi-reversible redox reaction.The oxidation-reduction reactive sites of these derivatives were located via geometry optimization using density functional theory(DFT)at the B3LYP/3-21g in the Guassian-09 level of theory.Remarkably,the most important contribution of this paper is the presentation of an entirely new group of terpyridine-based metallic dyes(chalcone-and flavone-based)and exploration of those dyes in the fabrication of Dye-Sensitized Solar Cells(DSSCs).DSSCs were constructed using these dyes and their efficiency was investigated by means of photovoltaic measurements.Results demonstrate that electron-donating substitutions provide better photovoltaic parameters on the ZnO surface as compared to electron-withdrawing groups.A detailed structure-property relationship has been established based on optical,electrochemical and photovoltaic properties studies.All experimental results were reinforced by computational approaches.
查看更多>>摘要：The photochromic reaction of 8H-pyranoquinazoline shows intriguing aspects in comparison to 3H-naph-thopyrans.These come from a stabilized excited singlet state for 8 H-pyranoquinazoline,which has a longer lifetime and is strongly sensitive to the solvent.The polar solvent acetonitrile reduces the quantum yield of coloured isomer formation(transoid-cis species).Colour fading related to the decay of transoid-cis population is faster than that for 3tf-naphthopyran family and occurs within few seconds time-window in solution at room temperature.Theoretical calculations show the crucial role in fading process played by the potential energy landscape,with the cisoid-cis intermediate located in a shallow high-energy minimum.
查看更多>>摘要：Two D-A compounds consisting of the highly electron-deficient triazine group are used as the electron-acceptor center,connected by a benzene ring through C-C single bond with three electron-giving carbazole groups,which were successfully synthesized and photophysical properties were studied.The UV-Vis spectra of both compounds have carbazole moiety,the strong absorption band at-300 nm mainly attributed to the π-π* transition of the carbazole,and the structured absorption band at-350 nm,mainly attributed to the n-π* transition of carbazole moiety.Meanwhile,the UV absorption and fluorescence emission of two triazine-carbazole compounds under different strong acid conditions were discussed.Also,the electrochemical properties of the two compounds were characterized by cyclic voltammetry and calculated the density functional theory(DFT),as well as their fluorescence emission and stability under different pH conditions were measured.The results show that compound of A-2 have good photophysical and electrochemical properties in acidic environment,and as effective acid affinity fluorescent dyes,in expectation of coping with the frequent occurrence of acid rain caused by environmental pollution,while the compound B-2 is insensitive to acidic conditions,and can be used as an acid-resistant dye on the surface of the material.
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