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Four 9,10-dithienylanthracene-based triphenylamine derivatives (TPA-DTAs) have been synthesized. Their properties, including AIEE, mechanofluorochromic, and cell imaging were investigated.

A new tetrarylethylene-based AIEE fluorescent dye (BTAE-PA) with multi-responsiveness and multicolored changes has been synthesized. Its properties, including AIEE, acidichromism, metal ion responsivity, and bioimaging were investigated.

A novel colorimetric/fluorescent chemosensor (1o) was designed and synthesized for the detection of CN− and Al3+.

A novel multi-responsive diarylethene derivative (1O) by linking a fluorescein group has been synthesized. Colorless 1O not only displayed good photochromic property to form cyclization state 1C, but also the 1C having multi-responsive characteristic to Cu2+ and basic stimulations. After Cu2+ was introduced, 1C showed excellent absorption and fluorescent spectra changed upon binding with Cu2+. The color of 1C solution turned from purple to colorless and the corresponding fluorescence color changed from dark to yellow, and the binding stoichiometry of 1C to Cu2+ was 1:1 and the detection limit was 0.11 µM. Moreover, 1C displayed distinctly reversible change on absorption and fluorescent spectra in basic environment, the basic environment can discolor the solution and turn on the fluorescence effect, suggesting that 1C can be used as pH sensor.

A novel fluorimetric and colorimetric chemosensor (1O) was synthesized with diarylethene-rhodamine unit and characterized by ESI–MS, 1H NMR, and 13C NMR. The chemosensor can selectively recognize extremely low concentrations of Hg2+ over a variety of metal ions with remarkable colorimetric and fluorescent responses. The colorimetric and fluorescent changes were ascribed the reaction between 1O and Hg2+ destructed the rhodamine hydrazide into open-ring form which was proved by mass spectrometry and nuclear magnetic titration analyses. The detection limits of the UV absorption and fluorescence methods for Hg2+ were found to be 0.708 μM and 24.6 nM, respectively. Moreover, the chemosensor exhibited excellent photochromism and outstanding fatigue resistance property under alternating UV and visible light irradiation. The application potential of the chemosensor was demonstrated with the qualitative detection of Hg2+ in real water samples.

Blending of poly(L-lactic acid)/poly(D-lactic acid) (PLLA/PDLA) leads to the formation of poly(lactide) stereocomplexation (PLA SC), which exhibits higher melting temperature and faster crystallization rate. The crystallization behavior of PLA homochiral crystallization (HC) under the existence of PLA SC was also widely investigated. During the variable processing, the SC with different morphologies would produce, and these SC could exert different influences on the subsequent formation of HC. However, the effects of SC developed in various conditions on the formation of HC are not compared yet and are also not clear until now, and which is important for the application of PLLA/PDLA blends. In this paper, the PDLAs with different molecular weights were blended with PLLA at a weight ratio of PLLA/PDLA 90/10, and the crystallization behaviors of PLLA HC from different conditions were investigated by differential scanning calorimetry (DSC). Results indicated that, incorporating a small amount of PDLA accelerated the formation of PLLA HC significantly regardless of the SC developed from the solution evaporation or the melt. The higher crystallization rate of HC was received in the PLLA/PDLA specimens with lower molecular weight of PDLA. For the specimens crystallized from the partially melting (most of SC developed during solution evaporation), the crystallization rate was higher than that corresponding specimens crystallized from the completely melting state (the SC were produced from the melt). This discrepancy would be due to variable SC morphologies produced during diverse processing.

A new europium complex Eu(tta)3L1 (1a) based on 1,10-phenanthroline derivative (L1 = (2-(3,5-dimethoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), tta = 2-thenoyltrifluoroacetone) was designed and synthesized. Its structure was characterized by 1H and 13C NMR, elemental analysis, UV-vis, fluorescence spectra and single crystal X-ray diffraction. The crystal of the complex 1a belongs to monoclinic system with the space group P21/n. The europium complex 1a in the solid and in the solution displays the typical emission of Eu(III) ion centered at 612 nm as a result of the electric dipole transition (5D0 → 7F2). It exhibits high quantum yield (20.42%), long lifetime (0.29 ms) and good CIE color coordinate (0.67, 0.33) in solid. In addition, the complex shows high sensitivity and selectivity towards Al3+ and Zn2+ in methanol solution which can be attributed to the Al3+/Zn2+ cation instead of Eu3+ in the complex 1a. The LODs for Al3+ and Zn2+ were calculated to be 5.880 × 10−7 and 7.678 × 10−8 mol/L, respectively. Besides, the additions of Al3+ and Zn2+ express remarkable color changes from red to bright blue and ivory that can be clearly observed by the naked eye respectively.

Phosphate (PO43−) plays a major role in aquatic ecosystems and biosystems. Developing a highly sensitive and selective ratiometric fluorescence probe for detection of PO43− is of great significance to the ecological environment and human health. In this work, a novel dual lanthanide metal organic framework was synthesized via hydrothermal reaction based on Tb3+ and Ce3+ as the center metal ions and terephthalic acid as the organic ligand (designated as Tb-Ce-MOFs). The fluorescence of Tb-Ce-MOFs shows emission at 375 nm. In the presence of PO43−, with increased concentration of PO43−, the fluorescence intensity of Tb-Ce-MOFs at 500 nm and 550 nm increased, while the intensity at 375 nm was reduced. Hence, ratiometric fluorescence detecting of PO43− can be achieved by measuring the ratio of fluorescence at 550 nm (FL550) to 375 nm (FL375) in the fluorescent spectra of the Tb-Ce-MOFs. In this sensing approach, the Tb-Ce-MOFs probe exhibits highly sensitive and selective for detection of PO43−. The limit of detection is calculated to be 28 nM and the detection range is 0.1 to 10 μM. In addition, the Tb-Ce-MOFs were used in the detection of PO43− in real samples.

In this paper, we successfully synthesized a simple and versatile fluorescent probe. This probe was not only easily prepared with a high yield, but also showed rapid selective and sensitive responses for Cys/Hcy and GSH. The probe can be used as a naked-eye detector for Cys/Hcy and GSH from other analytes. As a fluorescent sensor, it can be used to simultaneously detect and discriminate Cys/Hcy from GSH with two fluorescent emission signals without spectral crosstalk.

Using 4-([2,2': 6', 2'- terpyridin] -4'-yl) -N, N-dimethylaniline (tdl) as auxiliary ligand and 6-azido-2,2'-bipyridine (abp) as recognition ligand, a europium complex fluorescent probe Eu(4-([2,2': 6', 2'-terpyridin] -4' -yl) -N, N-dimethylaniline)

Herein, boric-acid-modified multifunctional Zr-based metal-organic frameworks (denoted as Fe3O4@PDA@B-UiO-66) were synthesized by hydrothermal reaction and surface modification. Compared to traditional matrix, Fe3O4@PDA@B-UiO-66 has the advantages of high ionization efficiency, high surface area, low matrix background, porous structure, and numerous boric-acid-active sites. By combining matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), Fe3O4@PDA@B-UiO-66 was used as an adsorbent and matrix for enrichment and detection of glucose, based on a specific reaction between boric acid and glucose. The limit of detection was 58.5 nM. The proposed method provides a simple and efficient approach for the sensitive and quantitative detection of glucose in complex samples based on MALDI-TOF MS.

A novel donor–acceptor fluorescent sensor was designed and synthesized. The sensor exhibited high selectivity and sensitivity to Zn2+ in acetonitrile solution. When 3.0 equiv. of Zn2+ was added gradually, the emission intensity at 500 nm increased 54-fold, accompanied by the fluorescent color of the solution changed from dark to green. Job’s plot and ESI-MS were carried out to verify a 1:1 stoichiometric complex was formed between the sensor and Zn2+. The limit of detection (LOD) to Zn2+ was measured to be 2.81 × 10−9 mol L−1. Moreover, the sensor not only could be used to detect Zn2+ in practical water samples with high accuracy, but also could be made into test paper for the qualitative detection for Zn2+.

Solid photocatalysts with high specific surface area, superior photoactivity and ease of recycling are highly desired in chemical process, water treatment and so on. In this study, a facile stepwise sol-gel coating approach was utilized to synthesize Pt decorated oxygen-deficient mesoporous titania microspheres with core-shell structure and convenient magnetic separability (denoted as Fe3O4@SiO2@Pt/mTiO2-x). These photocatalysts consist of magnetic Fe3O4 cores, nonporous insulating SiO2 middle layer and mesoporous anatase TiO2-x shell decorated by Pt nanoparticles (?3.5 nm) through wet impregnation and H2 reduction. As a result of high activity of oxygen-deficiency of black TiO2-x by H2 reduction and efficient inhibition of electron-hole recombination by Pt nanoparticles, the rationally designed core-shell Fe3O4@SiO2@Pt/mTiO2-x photocatalysts exhibit superior photocatalytic performance in rhodamine B (RhB) degradation under visible light irradiation, with more than 98% of RhB degraded within 50 min. These core-shell structured photocatalysts show excellent recyclability under the assistance of magnetic separation with well-retained photocatalytic performance even after running five cycles. This stepwise synthesis method paves the way for the rational design of a high-efficiency recyclable heterogeneous catalyst, including photocatalysts, for various applications. - 2019 This work was supported by the National Natural Science Foundation of China (Nos. 51372041 , 51422202 , 21673048 , 21875044 , 51822202 and 51772050 ), Key Basic Research Program of Science and Technology Commission of Shanghai Municipality (No. 17JC1400100 ), Youth Top-notch Talent Support Program of China, Shanghai Rising-Star Program (No. 18QA1400100 ) and DHU Distinguished Young Professor Program . Scopus

Blending of poly(l-lactide) and poly(d-lactide) (PLLA, PDLA) results in the formation of poly(lactide) stereocomplex crystallites (SC). For the preparation method, numerous reports employed solution mixing and stirring to receive a product with uniform performance. However, the effect of stirring time during solution mixing on the subsequent crystallization behavior did not clear yet, and which is important for solution crystallization, casting and spinning. In this paper, linear PLLA and PDLA with various molecular weights were synthesized. The PLLA and PDLA solutions were mixed together and stirred for different times before casting. Results revealed that the structures of PLA SC and homochiral crystallites (HC) did not vary with change in the stirring time. More amount of content of SC with uniform structure and less amount of content of HC were produced in the specimens stirred for longer time. When the specimens crystallized either from the melt or from the melt-quenching, less amount of content of crystallites (total crystallinity of SC and HC) was produced and the melting temperature of SC and HC depressed in the specimens that were stirred for longer time. With the increase in molecular weights, the effect of stirring time on the crystallization behaviors declined. This investigation provides a route to tailor the crystallization behavior of PLLA/PDLA specimens.

A novel turn-on mode fluorescent diarylethene containing a 4,6-dimethylpyrimidine unit was developed to fluorescently sense Zn2+. Its multiple-responsive properties induced by Zn2+/EDTA and ultraviolet/visible light have been systematically studied. The fluorescence sensor could efficiently detect Zn2+ with a 10 times enhancement of emission intensity and fluorescence color change (dark-green). In addition, the sensor showed clear discrimination from Cd2+. The limit of detection of the sensor was measured to be 8.48 × 10−8 mol L−1 for Zn2+. Finally, a molecular logic circuit was fabricated with the emission at 528 nm as the output signal and light and chemical stimuli as input signals.

In this work, we have developed amino-functionalized copper-based metal–organic frameworks (NH2-Cu-MOFs) for the detection of hypochlorite (ClO−). NH2-Cu-MOFs were synthesized using a one-pot hydrothermal method, and they exhibit strong fluorescence at 455 nm under the excitation of 330 nm. In the presence of ClO−, the fluorescence of NH2-Cu-MOFs was quenched due to the electron transfer between NH2-Cu-MOFs and ClO−. The NH2-Cu-MOFs exhibited 87.6% fluorescence quenching efficiency with 12.5 μM ClO− and the limit of detection is 0.036 μM. NH2-Cu-MOFs exhibited the advantages of high sensitivity, high selectivity, and low response reaction time for ClO− detection. This work developed a novel fluorescent probe for the detection of ClO− and the NH2-Cu-MOFs were successfully applied to analyse ClO− in real water samples.

The development of fluorescent dyes has been a continuing attractive research topic in the field of fluorescence sensing and bioimaging technologies, most of them were subject to a single signal change. In this work, a novel colorimetric and ratiometric fluorescent probe 1 based on rhodamine and anthracene groups was designed and synthesized via the fluorescence resonance energy transfer (FRET) mechanism. Probe 1 showed excellent selectivity, higher sensitivity and ratiometric response to Hg