查看更多>>摘要：We previously reported an organic fluorescent probe CBX for protamine detection. However, the detection limit, biocompatibility and stability can be further optimized. Considering the excellent performance of the current mesoporous materials, we tried to further prepare the nanocomposite probe based on 2-methylimidazole zinc salt (ZIF-8) using CBX for the purpose of improving the detection performance of CBX. Excitingly, this method has indeed provided a new type of metal-organic frameworks (MOFs) probe with excellent detection performance. In this work, three ZIF-8 materials with different morphologies by adjusting the ratio of zinc ion and ligand (2methylimidazole) were prepared, and three nanocomposite probes including CBX@ZIF-8 (1:2), CBX@ZIF-8 (1:4) and CBX@ZIF-8 (1:16) were synthesized. Experimental results showed that CBX@ZIF-8 (1:16) has the lowest detection limit for protamine. Also, the signal-to-noise ratio of these nanocomposite probes are much higher than that of free probe CBX. Differential charge data analysis suggests that the N atom on the imidazole of the ZIF-8 materials can effectively increase the electronegativity of the carboxyl group, enhance the electrostatic interaction with protamine, and improve the detection sensitivity. This work can inspire the researchers to develop novel nanocomposite probes for sensitive detecting biomolecules.
查看更多>>摘要：Two kinds of small molecular dyads (SMDs) based on trithiophene-benzodithiophene-rhodanine (DR3TBDT) main backbone and PBI termini, named SMD2-C6 and SMD2-C12, were designed with different lengths of alkyl linkers (C6H12 and C12H24). The length effect of alkyl linkers on the photovoltaic performance of the two SMDs have been systematically studied. The results show that the length of alkyl linkers can simutaneously tune the energy levels and phase separation in molecular dyad thin films. As a result, a power conversion efficiency of 1.33% was obtained for SMD2-C12 based single-component organic solar cells (SCOSCs), showing higher opencircuit voltage, short-circuit current density, and fill factor than those of SMD2-C6 based devices. Our findings provide a strategy for designing new SMDs and reveal the importance of alkyl linkers' length on the morphology of SMDs toward improved SCOSC performance.
查看更多>>摘要：A composite pigment of C. I. pigment red 177 (P. R. 177) with a core-shell structure was prepared via a solid-state ball milling method. The sepiolite was firstly acidified and used as the inorganic core. Effect of time and temperature on the particle size of acidified sepiolite was studied. P. R. 177 and the chosen acidified sepiolite were then mixed in a ball milling jar to prepare the composite pigment. When the sepiolite content was 20% (accounting for the weight of the pigment), the optical properties of the composite pigment reached the level of the commercial P. R. 177 and the coloring force was 113.38%. FT-IR, SEM and TEM analysis showed that sepiolite was coated with P. R. 177 and formed the core-shell structure while sepiolite was not completely coated by pigment from XRD measurement. The melting enthalpy obtained from DSC suggested that mechanical energy could be transformed into chemical bonding energy through the ball milling method and the chemical bonding was further confirmed with IR spectra. Performance tests showed that the prepared composite pigment has a greater water dispersibility and a better light fastness compared with that of commercial P. R. 177 while they have almost the same ethanol resistance level.
查看更多>>摘要：A major challenge of photodynamic cancer therapy is to improve the selectivity of photosensitizers to the target pathological tissue. To overcome this issue, a series of chlorophyll derivatives containing thiadiazole sulfonamide moiety or 4-(2-aminoethyl)benzene sulfonamide moiety were designed and synthesized. These compounds showed intense absorption at 670 nm with high molar extinction coefficients, and strong fluorescence emission around 674 nm. Their singlet oxygen generation ability was also demonstrated to be excellent. They displayed obvious photo-cytotoxic effects to MDA-MB-231 cells in vitro and to tumor-bearing Balb/c nude mice in vivo. The fluorescence images exhibited that N-[2-((5-Sulfamoyl-1,3,4-thiadiazol-2-yl)amino)-2-oxoethyl]pyropheophorbide (AZ-Ppa-2) preferentially accumulated in MDA-MB-231 cell lines overexpressing CAIX (Carbonic anhydrase IX). Molecular Docking simulation revealed that AZ-Ppa-2 could closely bind to the active site residues of CAIX. Sub-organelle localization test indicated that AZ-Ppa-2 primarily localized in the lysosomes. These experiments suggested that AZ-Ppa-2, as a photosensitizer targeting CAIX, possessed an outstanding PDT anti-tumor effect with lasting regression of tumors, and deserved for further study.
查看更多>>摘要：Herein, P and Cl doped carbon dots (P/Cl-CDs) were prepared by a simple hydrothermal method. An obvious chemiluminescence (CL) signal was obtained when the P/Cl-CDs coexisted with acidic KMnO4, and then a stronger CL signal appeared when NaHSO3 was added into the mixed solution of KMnO4 and P/Cl-CDs. The CL property and mechanism of P/Cl-CDs in the presence of KMnO4 or/and NaHSO3 have been elucidated. It was found that iodide ion (I-) could strongly inhibit the CL signal of the P/Cl-CDs-KMnO4-NaHSO3 system, and the degree of inhibition was proportional with the concentration of I-. The finding was used to design a method for the determination of I-. Under the optimum conditions, the CL signal of P/Cl-CDs-KMnO4-NaHSO3 system decreased linearly with the logarithm of I- concentration in a range of 0.1-70.0 mu M, and the detection limit was 90.0 nM. The method was applied to the determination of I- in edible salt samples. Conceivably, this novel CL system paves the way to numerous new assays based on the use of heteroatoms doping carbon dots.
查看更多>>摘要：New thiazole-condensed single and double germole derivatives (DTzG and GIDTz) were prepared by the reactions of respective lithiated thiazole compounds with dichlorodioctylgermane. The compound structures were verified by H-1 NMR, C-13 NMR, and mass spectral measurements. The single-crystal structure of brominated GIDTz shows high planarity of the fused ring system with intermolecular pi-pi stacking. The optical and electrochemical properties of DTzG and GIDTz derivatives indicate that the derivatives possess enhanced electron deficiency compared with thiophene-based germole congeners reported previously. This is supported by density functional theory calculations that reveal lower-lying HOMO and LUMO for the thiazole-condensed germoles than the thiophene-condensed congener.
查看更多>>摘要：The liver, which is an important internal organ and digestive gland of the human body, plays essential roles in metabolism and detoxifictaion. Due to frequently expose to toxic substances, the liver is susceptible to injury. Peroxynitrite (ONOO-) is a kind of ROS/RNS, which generally formed by the diffusion-limited reaction of O2 center dot- and NO. Some evidences have been confirmed that the production of ONOO- was related to the drug-induced liver injury (DILI). Therefore, developing accurate analytical methods for detecting ONOO- of DILI-related diseases will further ascertain the mechanisms of drug-induced hepatotoxicity. In this work, probe BDPP with fast reponse, high selectivity and good senstivity was successfully constructed and utilized for detecting peroxynitrite in live cells and zebrafish. What's more, in the APAP-induced hepatotoxicity model cells, the probe BDPP could detect the up-regulated expression of ONOO- and evaluate the remediation of NAC. The probe BDPP may as a promising tool for the detection of ONOO- during drug-induced hepatotoxicity related assays.
查看更多>>摘要：Concentration-dependent dynamically equilibrating systems play a crucial role in biology, supramolecular assemblies, and materials science. Herein, host-guest interaction triggered fluorescence emissions have been exploited to monitor concentration-dependent superstructures including a supramolecular polymer and dimers in aqueous solution. Given the unique photophysical properties associated with the dye guest in the cucurbit [8] uril-based rigid confined cavity, the resulting host-guest interactions exhibited unprecedented concentrationdependent dynamic assemblies. These can be clearly distinguished by multiple fluorescence emissions and by the naked-eye under UV-light. This work provides new insight for designing and characterizing dynamic equilibria in host-guest chemistry and materials science.
查看更多>>摘要：Zinc and aluminum ions are widespread in nature and human bodies. Disorder of these metal ions is not only closely related to various physiological and pathological processes but also an important biomarker in many diseases. Herein, we constructed a novel multifunctional fluorescent probe (HL) for specifically detecting Zn2+/ Al3+. The addition of Zn2+/Al3+ trigger the fluorescence enhancement of the probe ((lambda ex) = 400 nm/385 nm, lambda(em) = 510 nm/450 nm) in aqueous media/in ethanol, probably due to aggregation-induced emission (AIE) effect and the inhibited PET process/the formation of 1:1 stoichiometric L-Al complex inhibiting PET process. More importantly, besides fluorescence imaging of Zn2+/ Al3+ in PC3 cells, the probe has been applied successfully to determination of serum Zn2+ level in liquid biopsy of serum of prostate cancer confirms its diagnostic value in accurate detection for prostate cancer.
查看更多>>摘要：In this work, novel nitrogen, fluorine co-doped carbon dots (N, F-CDs) have been synthesized by a hydrothermal method using melamine and 2, 4-difluorobenzoic acid as precursors. The obtained N, F-CDs exhibit excellent optical stability with high quantum yield. The N, F-CDs are highly selective to S2- detection by forming N, FCDs@S2- , with a detection limit of 168 nM. The N, F-CDs@S2- were shown to be a highly selective Cd2+ detector by forming CdS, with a detection limit of 340 nM. The fluorescence quenching of N, F-CDs by S2- occurs via a static quenching mechanism and the fluorescence recovery was due to the high affinity of Cd2+ to S2-. The fluorescent sensor was used to determine Cd2+ and S2- in tap waters with satisfactory results.
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Elsevier