查看更多>>摘要：As a reactive oxygen species(ROS),endogenous peroxynitrite is closely involved in several pathophysiological processes.The development of a peroxynitrite probe would be necessary to clarify the role of peroxynitrite in pathophysiology.In this study,a new fluorescent probe TPPT was synthesized to detect peroxynitrite with high specificity and sensitivity.The results demonstrated that TPPT exhibits a fluorescence turn-on response to peroxynitrite because of the peroxynitrite-triggered oxidative reaction.The reaction product was analyzed by several methods,and the mechanism of the peroxynitrite-triggered oxidative reaction was discussed.The efficacy of TPPT for intracellular peroxynitrite imaging was demonstrated systematically.The results showed that TPPT can successfully visualize intracellular peroxynitrite in RAW264.7 cells,zebrafish,and live mouse tissues.
查看更多>>摘要：Dual-emitting ratiometric optical thermometers with the advantages of excellent self-calibration and high-sensitivity have become a research hot spot.Herein,a dual-emissive 4-methylumbelliferone encapsulated ZIF-8(ZIF-8d4-MU)modified Zn2GeO4:Mn~(2+)nanocomposite was simply prepared by adding Zn2GeO4:Mn~(2+)nano-rods into a methanol solution containing 4-methylumbelliferone(4-MU),zinc(II)nitrate hexahydrate,and 2-methylimidazole.Accompanying with the self-assembly of ZIF-8d4-MU,the binding affinity of Zn~(2+)ions to the surface of Zn2GeO4:Mn~(2+)nanorods enables the formation of ZIF-8D4-MU@Zn2GeO4:Mn~(2+)nanocomposite.The photoluminescence violet-blue(420 nm)and green emissions(531 nm)of the nanocomposite can be ascribed to the two independent luminescent centers of 4-MU dyes confined in ZIF-8 and the characteristic transition of 4T1-6A1 for Mn~(2+)ions doped in Zn2GeO4,respectively.The fluorescent intensity ratios(FIRs)of 4-MU to Mn~(2+)(I _(420)nm/I_(531)nm)showed excellent self-calibrating temperature monitoring functions with a maximum relative sensitivity(Sr)of 1.82%-℃_1 and stable reusability in the temperature range of 20-100 ℃.Also,the ZIF-8>4-MU@Zn2GeO4:Mn~(2+)hybridized polyvinyl alcohol(PVA)transparent film showed a similar multi-emitting behavior,as well as good processability and tensile properties.Benefiting from the excitation-dependent emitting property of ZIF-8>4-MU@Zn2GeO4:Mn~(2+),a multiple optical encryption of digital information was successfully realized based on a two-dimensional code,achieving an enhanced security level for preventing counterfeiting.This proof-of-concept study offers a feasible assembled way in fabricating multi-mode luminescent nanocomposites for ratiometric temperature sensing and information encryption.
查看更多>>摘要：The poly amino acid ionic liquid {1-ethyl-3-benzyltriethylammonium alanine P[ETA][Ala]} was synthesized and characterized with Fourier Transform Infrared Spectroscopy(FTIR),Carbon Nuclear Magnetic Spectra(~(13)C NMR),Scanning Electron Microscope(SEM),X-ray(XRD),Brumaire-Emmett-Teller(BET).SEM and BET confirmed that P[ETA][Ala] was a porous material.Under optimized conditions,the linear range of sunset Yellow(SY)was 0.02-20.00 μg mL~(-1),the limit of detection(LOD)was 0.01 μg mL~(-1)and the enrichment factor was 11.0(pre-extraction solution volume/elution volume).The isothermal adsorption and kinetic models were investigated to explain the extraction(adsorption)mechanism of SY on P[ETA][Ala],This proposed method was successfully applied the analysis of beverage samples with recoveries of 92.0-110.0% and relative standard deviations of 1.1-5.0%.
查看更多>>摘要：In this paper,two photosensitizers RFP-OH and RFP-Ac based on red fluorescent protein chromophore analogue with NIR emission was synthesized for photodynamic therapy(PDT)in A-549 cells and zebrafish.After the introduction of p-hydroxystyrene and acryloyl ester,the emission wavelengths of RFP-OH and RFP-Ac were red-shifted to the NIR band,which were 721 nm and 758 nm,respectively.And the stokes shift of RFP-OH and RFP-Ac was as large as 228 nm and 260 nm,respectively.The singlet oxygen yield of RFP-OH and RFP-Ac was 35.6% and 28.8%,respectively.Tumor cells are rich in biological thiols,such as Cys.After RFP-Ac encountered with Cys,the singlet oxygen yield of the products increased to 34.1%.In addition,DFT calculations showed that RFP-OH can transition to triplet state through intersystem crossing after being excited to singlet state,thereby enhancing the singlet oxygen yield.Both RFP-OH and RFP-Ac showed low dark toxicity(>91.02%),high photo toxicity,and good PDT effects in A-549 cells and zebrafish.More importantly,RFP-OH exhibited superior two-photon fluorescence imaging properties in zebrafish.In a word,considering to the positive results of the experiments,RFP-OH and RFP-Ac had a great potential for PDT in anti-cancer therapy.
查看更多>>摘要：Two polycyclic non-fullerene acceptors BTMe-OEH-2F and BTMe-OEH-2Cl were constructed by connecting the fused ring core with 4-(2-ethylhexyloxy)phenyl side chain to two kind of end groups 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile(2F-IC)and 2-(5,6-dichloro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile(2C1-IC),respectively.Compared with BTMe-OEH-2F,BTMe-OEH-2Cl showed a more red-shifted absorption and lower energy level.When the two non-fullerene acceptors were blended with the donor PM6,a fiber distribution and continuous nanophase separation can be observed in the PM6:BTMe-OEH-2Cl blend film,and more balanced charge transport and less charge recombination were exhibited in the organic solar cell(OSC)device based on BTMe-OEH-2Cl,which achieved a higher PCE of 13.23% with a V_(oc)of 0.98 V,a J_(sc)of 18.76 mA cm-2 and a FF of 72.23%.These results proved that the synergistic effect between side chains and end groups on the properties of fused-ring electron acceptors(FREAs)can be exerted by choosing appropriate end groups to match with alkoxy side chains.
查看更多>>摘要：In this study,two novel bipyridine-based Ru(II)complexes(Ei-Ru and E2-Ru)which contain different number of 3,4-ethylenedioxythiophene(EDOT)groups were synthesized and subjected to electrochemical polymerization both in absence and presence comonomer(EDOT).The resultant metallopolymers were examined in terms of their electrochemical and electrochromic properties.Cyclic voltammetry and spectroelectrochemistry studies revealed the ambipolar and multichromic nature of all the polymers where the reversible redox activity in the cathodic region was found to be mainly due to ligand centered reduction of the complex(Ru~(2+/1+)and Ru~(1+/0)and metal centered oxidation(Ru~(2+/1+))was found to be available along with redox activity of the conjugated backbone of the polymers in the anodic region.Contrary to pristine PEDOT all polymers displayed vibrantly multichromic behavior thanks to superimposed but independently functioning electrochromic/redox nature of the conjugated polymer backbone and the Ru complex.In general,increasing the number of polymerizable units in the monomer structure increased the quality of the films and brought color diversity to these metallopolymers.Copolymerization,on the other hand,not only contributed positively to the band gap and switching time but also widened the color pallet of these polymers which became even more remarkable upon changing the comonomer feed ratio.
查看更多>>摘要：Noncovalent dimerization usually can induce distinct luminescence properties from those of monomer,but it is quite difficult to achieve in solid state,especially in films.Two acridine(AC)derivatives pTPA-AC and mTPA-AC were designed and synthesized with the chemical modification of AC by electron-donating triphenylamine(TPA)substituent at para-and meta-positions of TPA unit,respectively.Their crystals were resolved with antiparallel π-π dimeric AC stacking,demonstrating green fluorescence.Their doped films in a polymer matrix exhibited a distinct emission color change from blue to green with increasing doping percentage of pTPA-AC and mTPA-AC,indicating a facile noncovalent dimerization of AC in neat films.Upon protonation,a high-contrast acid-responsive luminescence switching was observed in these films with increasing doping ratio,which possesses not only a significant color change but also an on-off switch characteristic.This work provides a new molecular design strategy to develop the dimer materials of organic heterocycles,facilitating the antiparallel π-π dimer stacking in the film for both novel functions and practical applications.
查看更多>>摘要：Mitochondria are vital organelles in eukaryotic cells,and can perform critical roles in supplying energy and maintaining cell functions.As a consequence,the design of mitochondria-targeting luminescent probes and the realisation of real-time mitochondrial activity acquisition are valuable tools in the study and therapy of mitochondrial dysfunction in diseases.Recently,lanthanide molecular compounds have emerged as potential mitochondria-targeting probes due to their low photobleaching propensity,sharp emission lines,and long excited-state lifetimes,which allow for time-resolved detection for increased sensitivity.A wide range of mitochondria-targeting luminescent lanthanide probes have been developed and employed for the detection of various reactive oxygen and bioactive species at the subcellular level in recent years,and the current review summarises all these advances.The design strategies,sensing mechanisms,and applications in bio-imaging of various reactive oxygen species in mitochondria are detailed here.
查看更多>>摘要：Photodynamic therapy(PDT)has been appeared as a promising clinical diagnosis and treatment for malignant tumor.However,its non-specific distribution and phototoxicity to normal tissues and skinspartially hinders the clinical applications of PDT in cancer diagnosis and therapy.Herein,2,4-dinitrobenzenesulfonyl chloride,a commonly used quenching agent,is introduced to conjugate with 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin for maximizing therapeutic effects and minimizing side effects of the photosensitizer.Owing to the conjugated 2,4-dinitrobenzenesulfonyl chloride,our designed photosensitizer TDBP can be activated by glutathione(GSH)and hydrogen sulfide(H2S)in solution and cancer cells,and then obtain recuperative fluorescence and photosensitive activity.Moreover,TDBP can achieve enhanced phototoxicity to GSH and H2S overexpressed cancer cells and reduced phototoxicity to normal cells and skins.Overall,the dual responsive photosensitizer developed here is a promising candidate for precisely therapy on GSH and H2S overexpressed cancer cells.
查看更多>>摘要：In this work,a series of new dyes,CQ-Cou,with a newly prepared chromophore acquired by hybridizing classic coumarin with chromenoquinoline,are designed and synthesized for the first time.We systematically investigated the photophysical properties of these chromenoquinoline-fused coumarin dyes and found they have the properties of relatively high fluorescence quantum yield,high photostability and molar absorption coefficient.Furthermore,the mechanisms of intramolecular charge transfer(ICT)related to donor and acceptor in these chromophores were researched by the theoretical calculations using density functional theory(DFT)and time-dependent density functional theory(TD-DFT).Importantly,the successful application of these new dyes in biological imaging for living cells and zebrafish is demonstrated.
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