Bin Xu

Solid-State Photoinduced Luminescence Switch for Advanced Anticounterfeiting and Super-Resolution Imaging Applications

Co-reporter:Qingkai Qi, Chong Li, Xiaogang Liu, Shan Jiang, Zhaochao Xu, Richmond Lee, Mingqiang Zhu, Bin Xu, and Wenjing Tian

Journal of the American Chemical Society November 15, 2017 Volume 139(Issue 45) pp:16036-16036

Publication Date(Web):October 18, 2017

DOI:10.1021/jacs.7b07738

Solid-state organic photoswitches with reversible luminescence modulation property are highly attractive because of their wide prospects in advanced photonic applications, such as optical data storage, anticounterfeiting and bioimaging. Yet, developing such materials has long been a significant challenge. In this work, we construct an efficient solid-state photoswitch based on a spiropyran-functionalized distyrylanthracene derivative (DSA-2SP) that exhibits exceptional reversible absorption/luminescence modulation ability. Efficient photoswitching between DSA-2SP and its photoisomer DSA-2MC are facilitated by large free volumes induced by nonplanar molecular structures of DSA moieties, as well as the intramolecular hydrogen bonds between the DSA and MC moieties. Consequently, the excellent solid-state photochromic property of DSA-2SP is highly applicable as both anticounterfeiting inks and super-resolution imaging agents.

Direct Observation of the Symmetrical and Asymmetrical Protonation States in Molecular Crystals

Co-reporter:Suqian Ma, Jibo Zhang, Yingjie Liu, Jingyu Qian, Bin Xu, and Wenjing Tian

The Journal of Physical Chemistry Letters July 6, 2017 Volume 8(Issue 13) pp:3068-3068

Publication Date(Web):June 16, 2017

DOI:10.1021/acs.jpclett.7b01454

The symmetrical and asymmetrical protonation states are realized via the formation of intermolecular hydrogen bonds inside 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene (BP4VA) molecular crystals. With the protonation of H2SO4, BP4VA molecules are protonated symmetrically, while the molecules are asymmetrically protonated by introducing HCl. The different protonation states of BP4VA crystals result in various supramolecular interactions, aggregation states, and even tunable optical properties. It provides a fundamental principle to understand the effect of protonation in organic conjugated molecules and an approach to expanding the scope of organic functional materials.

Organic dye doped nanoparticles with NIR emission and biocompatibility for ultra-deep in vivo two-photon microscopy under 1040 nm femtosecond excitation

Co-reporter:Nuernisha Alifu, Lulin Yan, Hequn Zhang, Abudureheman Zebibula, Zhenggang Zhu, Wang Xi, Anna Wang Roe, Bin Xu, Wenjing Tian, Jun Qian

Dyes and Pigments 2017 Volume 143(Volume 143) pp:

Publication Date(Web):1 August 2017

DOI:10.1016/j.dyepig.2017.04.017

•NIR emissive organic dye TPABDFN with well nonlinear coefficient were synthesized.•TPABDFN-PSMA NPs show excellent optical, chemical stability and biocompatibility.•TPABDFN-PSMA NPs were found large two-photon absorption cross-section at 1040 nm.•3D in vivo brain vascular imaging of mice was reconstructed at 1040 nm-fs by NPs.•1.2 mm imaging depth was achieved in vivo brain vascular imaging of mice at 1040 nm.Nanoparticle-assisted near-infrared (NIR) bioimaging and two-photon fluorescence microscopy (TPFM) are two important technologies in biophotonic research. In this work, we synthesize the dye named 2-(4-bromophenyl)-3-(4-(4-(diphenylamino)styryl)phenyl)fumaronitrile (TPABDFN), which had a large two-photon absorption cross-section and bright NIR emission. The dyes were then encapsulated with poly(styrene-co-maleic anhydride) (PSMA), forming fluorescent nanoparticles. The TPABDFN-PSMA nanoparticles possessed high chemical and optical stability, good biocompatibility, as well as large two-photon absorption cross-section (5.56 × 105 GM). Furthermore, we combined NIR bioimaging and TPFM together, and utilized TPABDFN-PSMA nanoparticles as fluorescent contrast agents for two-photon excited NIR microscopic imaging, with a 1040 nm-femtosecond laser. In vivo angiography of mice ear and brain was performed. Due to the deep penetration capability of both 1040 nm-excitation and NIR emission light, a very large in vivo microscopic imaging depth (∼1.2 mm) was achieved. NIR emissive and biocompatible TPABDFN-PSMA nanoparticles have great potential in disease diagnosis and clinical therapies, where deep-tissue imaging is required.NIR emissive TPABDFN-PSMA-PEG nanoparticles with large two-photon absorption cross-section were intravenously injected into a mouse, and three-dimensional architecture of the blood vessels in the mouse brain was reconstructed vividly with two-photon fluorescence microscopy at imaging depth ∼1200 μm.Download high-res image (291KB)Download full-size image

Construction and function of a highly efficient supramolecular luminescent system

Co-reporter:Yingjie Liu;Suqian Ma;Wenjing Tian

Faraday Discussions 2017 (Volume 196) pp:219-229

Publication Date(Web):2017/02/20

DOI:10.1039/C6FD00166A

Aggregation-induced emission (AIE) provides a new way of achieving highly efficient luminescent materials. In this contribution, the self-assembly behavior, molecular stacking structure and photophysical properties of two polymorphs of a supramolecular co-crystal (C1 and C2) are investigated. The block-like crystal C1, packed in segregated stacking with strong π–π interactions between the H and G molecules, shows weak green emission with a low efficiency (ΦF) of 2%. In comparison, the needle-like crystal C2, packed in segregated stacking with no obviously strong intermolecular interactions, shows bright yellow emission. More importantly, C1 exhibits mechanochromic behavior.

Insights into the origin of aggregation enhanced emission of 9,10-distyrylanthracene derivatives

Co-reporter:Jibo Zhang;Suqian Ma;Honghua Fang;Hongbo Sun;Im Chan;Wenjing Tian

Materials Chemistry Frontiers 2017 vol. 1(Issue 7) pp:1422-1429

Publication Date(Web):2017/06/28

DOI:10.1039/C7QM00032D

9,10-Distyrylanthracene (DSA) and its four derivatives are investigated by both steady state and ultrafast spectroscopy to reveal the intrinsic photophysical process upon excitation. Intramolecular rotation around the vinyl moiety plays an important role in the whole photophysical process in addition to the electronic properties of the peripheral substituents. In dilute solutions, DSA derivatives possess a twisted structure in the ground state that eventually relaxes to a planar structure within picoseconds. The fluorescence process is dominated by the relaxed excited state, and the quantum yield is affected by competition between the nonradiative and radiative deactivations. The enhanced fluorescence of the molecular aggregates originates from the optically allowed S1–S0 transition together with the suppressed nonradiative deactivation via molecular stacking. These findings provide an in-depth understanding of the origin of the aggregation enhanced emission process, and may be applicable for the fine design of DSA based molecules with enhanced fluorescence and novel structures beyond DSA.

Highly efficient Far Red/Near-Infrared fluorophores with aggregation-induced emission for bioimaging

Co-reporter:Fengli Zhang, Yizeng Di, Yue Li, Qingkai Qi, Jingyu Qian, Xueqi Fu, Bin Xu, Wenjing Tian

Dyes and Pigments 2017 Volume 142(Volume 142) pp:

Publication Date(Web):1 July 2017

DOI:10.1016/j.dyepig.2017.04.004

•A series of highly efficient Far Red/Near-Infrared fluorescent compounds with aggregation-induced emission properties.•These compounds exhibit facile fabrication into uniform compound-loaded Pluronic F127 NPs.•These compounds are effective fluorescent probes for cancer cells with excellent properties.Organic fluorescent probes play an important role in modern biomedical research, such as biological sensing and imaging. However, the development of organic fluorophores with efficient aggregate state emissions expanded to the red to near-infrared region is still challenging. Here, we present a series of highly efficient Far Red/Near-Infrared (FR/NIR) fluorescent compounds with aggregation-induced emission (AIE) properties by attaching electron donor and accepter to tetraphenylethene (TPE) moieties through a simple synthesis method. These compounds exhibited the pronounced fluorescence enhancement in aggregate state, the red to near infrared emission, and can be facilely fabricated into uniform compounds-loaded Pluronic F127 NPs. The emission maximum of the NPs fabricated by the self-assembly method is in the range of 550–850 nm and the highest fluorescent quantum yield can get to 15.2%. The biological imaging of NPs of compound 1 and 2 for A549 lung cancer cell indicates that these compounds are effective fluorescent probes for cancer cells with high specificity, high photostability and good fluorescence contrast.Download high-res image (218KB)Download full-size image

Label-free detection for SNP using AIE probes and carbon nanotubes

Co-reporter:Ke Ma, Hui Wang, Haolong Li, Bin Xu, Wenjing Tian

Sensors and Actuators B: Chemical 2017 Volume 253(Volume 253) pp:

Publication Date(Web):1 December 2017

DOI:10.1016/j.snb.2017.06.055

•A novel optical platform was constructed for SNP analysis based on label-free fluorophore and water-soluble carbon nanotubes.•The sensing mechanism was established by studying the supermolecular interactions of fluorophore, carbon nanotubes and DNA.•The SNP analysis in random DNA sequence can be realized by this label-free optical platform.We design a label-free optical platform for SNP detection by using aggregation-induced emission (AIE) active molecule DSAI as the probe and water-soluble carbon nanotubes as the selective platform via the fluorescent quenching effect. In the presence of DNA, DSAI molecules aggregate on DNA through the intercalation and the electrostatic interaction as well as the hydrophobic interaction, resulting in the strong fluorescence in the solution. In order to distinguish the wild-DNA from the single nucleotide mutated-DNA, we induce the water-soluble carbon nanotubes as the effective fluorescent quenching material. The interactions between DSAI and wild-DNA are rather strong, thus DSAI molecules cannot be hauled out from wild-DNA and the fluorescence stays still. While the interactions between DSAI and single nucleotide mutated-DNA are relatively weak, and several DSAI molecules can be hauled out from the single nucleotide mutated-DNA by the water-soluble carbon nanotubes through the strong electrostatic interaction, leading to the partial fluorescent quenching in the solution. Therefore, the detection of SNP in the random DNA sequence could be realized by using AIE probes and carbon nanotubes.Download high-res image (104KB)Download full-size image

Fluorescent nanoparticles based on AIE fluorogens for bioimaging

Co-reporter:Lulin Yan, Yan Zhang, Bin Xu and Wenjing Tian

Nanoscale 2016 vol. 8(Issue 5) pp:2471-2487

Publication Date(Web):01 Oct 2015

DOI:10.1039/C5NR05051K

Fluorescent nanoparticles (FNPs) have recently attracted increasing attention in the biomedical field because of their unique optical properties, easy fabrication and outstanding performance in imaging. Compared with conventional molecular probes including small organic dyes and fluorescent proteins, FNPs based on aggregation-induced emission (AIE) fluorogens have shown significant advantages in tunable emission and brightness, good biocompatibility, superb photo- and physical stability, potential biodegradability and facile surface functionalization. In this review, we summarize the latest advances in the development of fluorescent nanoparticles based on AIE fluorogens including polymer nanoparticles and silica nanoparticles over the past few years, and the various biomedical applications based on these fluorescent nanoparticles are also elaborated.

Intracellular pH sensing using polymeric micelle containing tetraphenylethylene-oxazolidine

Co-reporter:Qingkai Qi, Yue Li, Xiaoyu Yan, Fengli Zhang, Shan Jiang, Jing Su, Bin Xu, Xueqi Fu, Liankun Sun and Wenjing Tian

Polymer Chemistry 2016 vol. 7(Issue 33) pp:5273-5280

Publication Date(Web):25 Jul 2016

DOI:10.1039/C6PY01072E

A novel amphiphilic copolymer consisting of tetraphenylethylene-oxazolidine (TPE-OX) as a pH-sensitive chromophore and poly(ethylene glycol) methyl ether methacrylate (PEGMA) as a water-soluble chain has been well designed and synthesized. A self-assembled polymeric micelle based on the copolymer exhibited clear dual-emission switching between cyan and red with a decrease of pH value in Tris-HCl buffer solution due to the extended conjugation and emerging intramolecular charge transfer effect when opening the spiro-ring of OX moiety. Fluorescence imaging of HepG2 cells stained by the polymeric micelle shows switched luminescence from cyan to red with high selectivity and contrast, indicating that the polymeric micelle was an effective probe for intracellular pH detection. Additionally, the red emission of the polymeric micelle in lysosomes can reversibly switch back to the original cyan emission in response to the two lysosomal activity inhibitors chloroquine and bafilomycin, which demonstrates that the polymeric micelle has potential applications in detecting the activity of lysosomal and further autophagy in cancer cells.

Trap-limited bimolecular recombination in poly(3-hexylthiophene): Fullerene blend films

Co-reporter:Yang Liu, Yajun Gao, Bin Xu, Paul H.M. van Loosdrecht, Wenjing Tian

Organic Electronics 2016 Volume 38() pp:8-14

Publication Date(Web):November 2016

DOI:10.1016/j.orgel.2016.07.018

•The dependence of the photoexcitation density, PC61BM composition, thermal annealing and thickness on Trap-limited bimolecular recombination has been investigated by photo-CELIV method in P3HT and PC61BM blend films.•The trap-limited bimolecular recombination is strongly affected by the distribution of the density of trap state (trap DOS).•The higher trap-limited bimolecular recombination rate means the trap DOS centered at lower energy which is beneficial to the releasing of trapped charge carriers, and leading to better charge carrier transportation.Trap-limited bimolecular recombination in poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) blend films has been investigated by using photo-induced charge extraction by linearly increasing voltage (photo-CELIV) method. The bimolecular recombination rate is strongly dependent on the photoexcitation density, the PC61BM composition and the thermal annealing process, but it slightly depends on the thickness of the blend film. The results show that the trap-limited bimolecular recombination is strongly affected by the distribution of the density of trap state (trap DOS). The higher trap-limited bimolecular recombination rate means the trap DOS centered at lower energy which is beneficial to charge carriers transportation, due to the lower activation energy and faster release rate. On the other hand, the trap-limited bimolecular recombination rate is mainly controlled by the slower species of charge carriers in the blend film when the transport of electrons and holes are strongly unbalanced, and the recombination rate will increase when the transport of electrons and holes becomes more balanced.

Supramolecular Hybrids of AIEgen with Carbon Dots for Noninvasive Long-Term Bioimaging

Co-reporter:Jianxu Zhang, Min Zheng, Fengli Zhang, Bin Xu, Wenjing Tian, and Zhigang Xie

Chemistry of Materials 2016 Volume 28(Issue 23) pp:

Publication Date(Web):November 18, 2016

DOI:10.1021/acs.chemmater.6b04894

Fluorescent bioprobes have been regarded as promising tools for bioimaging in recent years due to their excellent properties. However, the aggregation-caused quenching of emissions is a big limitation in practice for this strategy. Organic dyes with aggregation-induced emission (AIE) feature can effectively solve this problem. Herein, stable fluorescent nanoparticles were prepared by supramolecular assembling of carbon dots (CDs) and hydrophobic AIEgen. The formulated CDsG-AIE 1 exhibits superior physical and photo stability than AIE self-assembling nanoparticles in various physiology conditions. On the other hand, the formulated CDsG-AIE 1 also showed advanced features such as large Stokes shift, good biocompatibility, high emission efficiency, and strong photobleaching resistance. More importantly, the CDsG-AIE 1 can be readily internalized by HeLa cells, and strong red fluorescence from the nanoparticles can still be clearly observed after six generations over 15 days. In addition, the CDsG-AIE 1 also exhibits superior long-term imaging ability in vivo. These incredible features make the AIE nanoparticles to be an ideal fluorescent probe for noninvasive long-term tracing and imaging applications. This work highlights the potential of using carbon dots to assemble AIEgen for the preparation of nanoscale AIEgen-contained particles for desirable bioimaging and diagnostic.

Remarkable Turn-On and Color-Tuned Piezochromic Luminescence: Mechanically Switching Intramolecular Charge Transfer in Molecular Crystals

Co-reporter:Qingkai Qi;Jingyu Qian;Xiao Tan;Jibo Zhang;Lijuan Wang;Bo Zou;Wenjing Tian

Advanced Functional Materials 2015 Volume 25( Issue 26) pp:4005-4010

Publication Date(Web):

DOI:10.1002/adfm.201501224

The molecular crystals of acridonyl-tetraphenylethene (AD-TPE) exhibit an intriguing turn-on and color-tuned luminescence in response to mechanical grinding and hydrostatic compression. On the basis of in-depth experimental and computational studies, it is hypothesized that the origin of the piezochromic behavior from the D-phase to the B-phase is the change of the intramolecular geometrical conformation, especially for the torsion angle between the TPE and AD moiety. The different molecular conformation in the two distinctive solid phases causes the substantial switching of the intramolecular charge transfer (ICT) process, which can be directly correlated with the subsequent fluorescence from locally excited (LE) state and ICT state in both phases. The AD-TPE molecular system presents a very rare example of high-contrast reversible fluorescence tuning driven by a switching of the excited state in the solid state under the mechanical stimuli, and thus provides a novel mechanism of the piezochromic behavior.

Efficient Spontaneous and Stimulated Emission from 1,4-Bis(2,2-diphenylvinyl)benzene Single Crystals with Cross-Dipole Stacking

Co-reporter:Suqian Ma;Jibo Zhang;Jingyu Qian;Jinlong Chen;Wenjing Tian

Advanced Optical Materials 2015 Volume 3( Issue 6) pp:763-768

Publication Date(Web):

DOI:10.1002/adom.201400572

Low-Loss Optical Waveguide and Highly Polarized Emission in a Uniaxially Oriented Molecular Crystal Based on 9,10-Distyrylanthracene Derivatives

Co-reporter:Jinlong Chen, Suqian Ma, Jibo Zhang, Bao Li, Bin Xu, and Wenjing Tian

ACS Photonics 2015 Volume 2(Issue 2) pp:

Publication Date(Web):January 9, 2015

DOI:10.1021/ph5004384

A uniaxially oriented crystal based on 9,10-bis(2,2-di-p-tolylvinyl)anthracene (BDTVA) with an excellent waveguide and polarization performance has been prepared. The low loss coefficient (2.75 cm–1) and the high polarization contrast (0.72) may result from the uniaxially oriented packing and layer-by-layer molecular structure in the BDTVA crystal. Moreover, amplified spontaneous emission is observed from the BDTVA crystal with a low threshold of 265 μJ/cm2, and the gain coefficient is 52 cm–1 at the peak wavelength of 509 nm. These features indicate that the BDTVA crystal may be potentially applied in the field of optical waveguides and organic solid-state lasers.

Reversible Multistimuli-Response Fluorescent Switch Based on TetraphenyletheneSpiropyran Molecules

Co-reporter:Dr. Qingkai Qi;Jingyu Qian;Suqian Ma;Dr. Bin Xu; Sean Xiao-An Zhang ; Wenjing Tian

Chemistry - A European Journal 2015 Volume 21( Issue 3) pp:1149-1155

Publication Date(Web):

DOI:10.1002/chem.201405426

Abstract

Two tetraphenylethene (TPE)-functionalized spiropyran (SP) molecules with very similar structure were designed and synthesized. The two molecules exhibit aggregation-induced emission (AIE) properties, as well as multistimuli-responsive color-changing properties, such as photochromism and acidchromism. The investigation of their different photochromic and acidchromic characteristics and dual-response fluorescent switch during isomerization indicated that the different link position between TPE and SP will significantly affect the extended π-conjugated system, resulting in completely different photochromic and acidchromic properties.

An Organic Luminescent Molecule: What Will Happen When the Butterflies Come Together?

Co-reporter:Jibo Zhang;Jinlong Chen;Suqian Ma;Yujie Dong;Lijuan Wang;Bao Li;Ling Ye ;Wenjing Tian

Advanced Materials 2014 Volume 26( Issue 5) pp:739-745

Publication Date(Web):

DOI:10.1002/adma.201303639

Folic acid-functionalized AIE Pdots based on amphiphilic PCL-b-PEG for targeted cell imaging

Co-reporter:Yan Zhang, Yujue Chen, Xing Li, Jibo Zhang, Jinlong Chen, Bin Xu, Xueqi Fu and Wenjing Tian

Polymer Chemistry 2014 vol. 5(Issue 12) pp:3824-3830

Publication Date(Web):14 Feb 2014

DOI:10.1039/C4PY00075G

Fluorescent block amphiphilic copolymers are one of the most important bioimaging materials which are highly desirable for early stage cancer diagnosis and treatment. However, sometimes the application of the fluorescent block copolymers is severely limited because of the aggregation-caused quenching (ACQ) effect. In this study, new aggregation induced emission polymer dots (AIE Pdots) were prepared through a self-assembly process by using an AIE-conjugated block copolymer containing an AIE fluorophore, 9,10-bis(4-hydroxystyryl)anthracene, hydrophobic poly(ε-caprolactone) segments, hydrophilic poly(ethylene glycol) segments and folate groups. The AIE Pdots are monodispersed in H2O with an average diameter of 15 nm, and possess strong emission and high solid state fluorescence quantum efficiency (Φ = 27.0%). Furthermore, the AIE Pdots show good stability and little toxicity to living cells and thus can be utilized for targeted HeLa cell imaging. Biological imaging investigation indicated that the folic acid functionalized AIE Pdots can be applied for targeted HeLa intracellular imaging.

Fluorescent Aptasensor Based on Aggregation-Induced Emission Probe and Graphene Oxide

Co-reporter:Xing Li, Ke Ma, Shoujun Zhu, Shiyu Yao, Zhaoyang Liu, Bin Xu, Bai Yang, and Wenjing Tian

Analytical Chemistry 2014 Volume 86(Issue 1) pp:298

Publication Date(Web):December 3, 2013

DOI:10.1021/ac403629t

Recently, a great variety of aggregation-induced emission (AIE)-active molecules has been utilized to design bioprobes for label-free fluorescent turn-on aptasensing with high sensitivity. However, due to nonspecific binding interaction between aptamer and AIE probe, these AIE-based aptasensors have nearly no selectivity, thereby significantly limiting the development. In this work, a 9,10-distyrylanthracene with two ammonium groups (DSAI) is synthesized as a novel AIE probe, and the fluorescent aptasensor based on DSAI and graphene oxide (GO) is developed for selective and sensitive sensing of targeted DNA and thrombin protein. Given its AIE property and high selectivity and sensitivity, this aptasensor can be also exploited to detect other targets.

A sensitive and selective “turn-on” fluorescent probe for Hg2+ based on thymine–Hg2+–thymine complex with an aggregation-induced emission feature

Co-reporter:Ke Ma, Xing Li, Bin Xu and Wenjing Tian

Analytical Methods 2014 vol. 6(Issue 7) pp:2338-2342

Publication Date(Web):08 Jan 2014

DOI:10.1039/C3AY42255K

A fluorescent turn-on approach for the sensitive and selective sensing of Hg2+ based on an aggregation-induced emission fluorescent molecule (DSA-T2) containing 9,10-distyrylanthracene as a fluorophore and thymine as a Hg2+ receptor, was developed. Under optimum conditions, a linear relationship (R2 = 0.9894) was obtained between the fluorescent intensity and the concentration of Hg2+ from 7 × 10−7 mol L−1 to 1 × 10−5 mol L−1. The theoretical detection limit of Hg2+ was evaluated to be 3.4 × 10−7 mol L−1. And the selectivity towards Hg2+ was good compared to other metal ions.

Proton-Triggered Hypsochromic Luminescence in 1,1′-(2,5-Distyryl-1,4-phenylene) Dipiperidine

Co-reporter:Jinlong Chen, Suqian Ma, Jibo Zhang, Lijuan Wang, Ling Ye, Bao Li, Bin Xu, and Wenjing Tian

The Journal of Physical Chemistry Letters 2014 Volume 5(Issue 16) pp:2781-2784

Publication Date(Web):July 29, 2014

DOI:10.1021/jz501383d

A proton-triggered hypsochromic luminescent chromophore 1,1′-(2,5-distyryl-1,4-phenylene) dipiperidine (DPD) was designed and synthesized. Upon treatment by hydrochloric acid (HCl), the emission of DPD showed a large hypsochromic shift in both THF solution and microcrystals. Theoretical calculations and powder X-ray diffraction experiments reveal that the switchable emission of DPD originated from the change of the distribution and the spatial arrangement of the frontier molecular orbitals, and the different stacking modes of DPD in microcrystals also contribute to the switchable emission of DPD in aggregates.Keywords: acid/base stimuli; aggregating structure; frontier molecular orbitals; stacking mode; switchable fluorescent emission;

Multi-stimuli responsive fluorescence switching: the reversible piezochromism and protonation effect of a divinylanthracene derivative

Co-reporter:Yujie Dong, Jibo Zhang, Xiao Tan, Lijuan Wang, Jinlong Chen, Bao Li, Ling Ye, Bin Xu, Bo Zou and Wenjing Tian

Journal of Materials Chemistry A 2013 vol. 1(Issue 45) pp:7554-7559

Publication Date(Web):17 Sep 2013

DOI:10.1039/C3TC31553C

A novel divinylanthracene derivative 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene (BP4VA) was synthesized and its two polymorphs with different crystal structures were obtained. The introduction of pyridine in BP4VA leads to multi-stimuli responsive fluorescence. An investigation of the photophysical and stimuli responsive luminescent properties of BP4VA, including the piezochromism and protonation effect, demonstrates that the piezochromic luminescence originates from changes in the molecular aggregation state. Additionally, protonation–deprotonation of the pyridine moieties in BP4VA has a significant effect on the frontier molecular orbitals, resulting in distinct green and red emissions under acid and base stimuli. This study on BP4VA provides a comprehensive insight into the mechanisms within this type of stimuli-responsive luminescent material, and suggests that BP4VA may be a potential candidate for applications in sensing, detection and display devices with remarkable color-changing properties.

Remarkable fluorescence change based on the protonation–deprotonation control in organic crystals

Co-reporter:Jibo Zhang, Jinlong Chen, Bin Xu, Lijuan Wang, Suqian Ma, Yujie Dong, Bao Li, Ling Ye and Wenjing Tian

Chemical Communications 2013 vol. 49(Issue 37) pp:3878-3880

Publication Date(Web):21 Mar 2013

DOI:10.1039/C3CC41171K

Insights into the origin of the fluorescence responsive to protonation–deprotonation stimuli were provided through the study on the crystals of a new stimuli-responsive molecule BP3VA. And the transformation between microcrystals demonstrated the varying emissions of the BP3VA powder.

Organic Fluorescent Molecule with High Solid State Luminescent Efficiency and Protonation Stimuli-response

Co-reporter:Suqian Ma;Jibo Zhang;Jinlong Chen;Lijuan Wang;Wenjing Tian

Chinese Journal of Chemistry 2013 Volume 31( Issue 11) pp:1418-1422

Publication Date(Web):

DOI:10.1002/cjoc.201300583

Abstract

A novel organic fluorophor with high solid state luminescent efficiency based on 1,4-bis(2,2-di(pyridin-2-yl)vinyl)benzene (BDP2VB) was designed and synthesized. It emits faintly in solution, but becomes a strong emitter in the aggregate state, demonstrating its aggregation induced emission (AIE) property. According to the crystal structure analysis, J-type aggregation was formed in the packing mode of the molecule, which was demonstrated to be beneficial to gain high fluorescent quantum efficiency in solid state. Additionally, the emission color of BDP2VB can change dramatically in solid state as well as in solution by the protonation stimuli.

Oligo(phenothiazine)s: Twisted Intramolecular Charge Transfer and Aggregation-Induced Emission

Co-reporter:Jibo Zhang ; Bin Xu ; Jinlong Chen ; Lijuan Wang ;Wenjing Tian

The Journal of Physical Chemistry C 2013 Volume 117(Issue 44) pp:23117-23125

Publication Date(Web):September 30, 2013

DOI:10.1021/jp405664m

Two 9,10-divinylanthracene oligomers containing phenothiazines (AnPHZ2 and AnPHZ4) are synthesized, and their intramolecular charge transfer as well as aggregation-induced emission (AIE) properties are investigated. Both oligomers show typical AIE properties as well as solvent polarity dependent emission. Time-resolved fluorescence spectra revealed that the twisted intramolecular charge transfer state formed in polar solvents accounts for the weak emission with large Stokes shifts, and the interactions between solvent and solutes facilitate the nonradiative decay. The restriction of intramolecular torsion induced by supramolecular interactions in aggregates eliminates the charge transfer state, thus resulting in efficient AIE.

Mechanochromism and Polymorphism-Dependent Emission of Tetrakis(4-(dimethylamino)phenyl)ethylene

Co-reporter:Qingkai Qi ; Jibo Zhang ; Bin Xu ; Bao Li ; Sean Xiao-An Zhang ;Wenjing Tian

The Journal of Physical Chemistry C 2013 Volume 117(Issue 47) pp:24997-25003

Publication Date(Web):November 7, 2013

DOI:10.1021/jp407965a

The mechanochromic property of tetrakis(4-(dimethylamino)phenyl)ethylene (TDMAPE) with natural propeller shape and nearly centrosymmetric structure was investigated. The destruction of the crystalline structure leads to the planarization of molecular conformation, which is considered as a possible reason for the red-shift of absorption and fluorescence spectra after grinding. And the polymorphism-dependent emissions of the two polymorphs of TDMAPE are mainly determined by the intramolecular conformation, which show the increased coplanarity or conjugation degree, ultimately leading to the bathochromic shift of the emissions.

A highly sensitive “turn-on” fluorescent probe for bovine serum albumin protein detection and quantification based on AIE-active distyrylanthracene derivative

Co-reporter:ZiLong Wang;Ke Ma;Xing Li;WenJing Tian

Science China Chemistry 2013 Volume 56( Issue 9) pp:1234-1238

Publication Date(Web):2013 September

DOI:10.1007/s11426-013-4917-6

A sulfonated 9,10-distyrylanthracene derivative with aggregation-induced emission (AIE) property is designed and synthesized. It shows a highly sensitive and selective fluorescence enhancement property for bovine serum albumin (BSA) protein detection and quantification. Analysis on the interaction between the probe molecule and BSA reveals the essential role of the hydrophobic cavities of the protein folding structure.

Molecular crystals based on 9,10-distyrylanthracene derivatives with high solid state fluorescence efficiency and uniaxial orientation induced by supramolecular interactions

Co-reporter:JinLong Chen;SuQian Ma;JiBo Zhang;YuJie Dong

Science Bulletin 2013 Volume 58( Issue 22) pp:2747-2752

Publication Date(Web):2013 August

DOI:10.1007/s11434-013-5897-9

Two 9,10-distyrylanthracene (DSA) derivatives CNDSA and t-BUDSA were designed and synthesized, and their photophysical properties and crystal structures were investigated. Compared to DSA, the maximum emission peaks of the two compounds showed red-shift not only in THF solution, but also in crystals, because the introduction of electron-withdrawing substituents to DSA leads to more dispersion of the electrons in the molecules. The two crystals of CNDSA and t-BUDSA show strong fluorescence with the efficiency ΦF of 45% and 33%, respectively, which may be resulted from no obvious π-π interactions between molecules inside the crystal due to the large distance between the two adjacent molecules and nearly no overlap between the central anthracene planes. The analysis of crystal structures of the two compounds indicated that the molecules are arranged in the same conformation and orientation in their crystals, i.e. uniaxially oriented packing crystal, because of the supramolecular interaction of CH/π in the two crystals and additional C-H…N interactions in CNDSA.

Remarkable fluorescence change based on the protonation–deprotonation control in organic crystals

Co-reporter:Jibo Zhang, Jinlong Chen, Bin Xu, Lijuan Wang, Suqian Ma, Yujie Dong, Bao Li, Ling Ye and Wenjing Tian

Chemical Communications 2013 - vol. 49(Issue 37) pp:NaN3880-3880

Publication Date(Web):2013/03/21

DOI:10.1039/C3CC41171K

Insights into the origin of the fluorescence responsive to protonation–deprotonation stimuli were provided through the study on the crystals of a new stimuli-responsive molecule BP3VA. And the transformation between microcrystals demonstrated the varying emissions of the BP3VA powder.

Multi-stimuli responsive fluorescence switching: the reversible piezochromism and protonation effect of a divinylanthracene derivative

Co-reporter:Yujie Dong, Jibo Zhang, Xiao Tan, Lijuan Wang, Jinlong Chen, Bao Li, Ling Ye, Bin Xu, Bo Zou and Wenjing Tian

Journal of Materials Chemistry A 2013 - vol. 1(Issue 45) pp:NaN7559-7559

Publication Date(Web):2013/09/17

DOI:10.1039/C3TC31553C

A novel divinylanthracene derivative 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene (BP4VA) was synthesized and its two polymorphs with different crystal structures were obtained. The introduction of pyridine in BP4VA leads to multi-stimuli responsive fluorescence. An investigation of the photophysical and stimuli responsive luminescent properties of BP4VA, including the piezochromism and protonation effect, demonstrates that the piezochromic luminescence originates from changes in the molecular aggregation state. Additionally, protonation–deprotonation of the pyridine moieties in BP4VA has a significant effect on the frontier molecular orbitals, resulting in distinct green and red emissions under acid and base stimuli. This study on BP4VA provides a comprehensive insight into the mechanisms within this type of stimuli-responsive luminescent material, and suggests that BP4VA may be a potential candidate for applications in sensing, detection and display devices with remarkable color-changing properties.

A sensitive and selective “turn-on” fluorescent probe for Hg2+ based on thymine–Hg2+–thymine complex with an aggregation-induced emission feature

Co-reporter:

Analytical Methods (2009-Present) 2014 - vol. 6(Issue 7) pp:NaN2342-2342

Publication Date(Web):2014/01/08

DOI:10.1039/C3AY42255K

A fluorescent turn-on approach for the sensitive and selective sensing of Hg2+ based on an aggregation-induced emission fluorescent molecule (DSA-T2) containing 9,10-distyrylanthracene as a fluorophore and thymine as a Hg2+ receptor, was developed. Under optimum conditions, a linear relationship (R2 = 0.9894) was obtained between the fluorescent intensity and the concentration of Hg2+ from 7 × 10−7 mol L−1 to 1 × 10−5 mol L−1. The theoretical detection limit of Hg2+ was evaluated to be 3.4 × 10−7 mol L−1. And the selectivity towards Hg2+ was good compared to other metal ions.

Insights into the origin of aggregation enhanced emission of 9,10-distyrylanthracene derivatives

Co-reporter:Jibo Zhang, Suqian Ma, Honghua Fang, Bin Xu, Hongbo Sun, Im Chan and Wenjing Tian

Inorganic Chemistry Frontiers 2017 - vol. 1(Issue 7) pp:NaN1429-1429

Publication Date(Web):2017/03/01

DOI:10.1039/C7QM00032D

9,10-Distyrylanthracene (DSA) and its four derivatives are investigated by both steady state and ultrafast spectroscopy to reveal the intrinsic photophysical process upon excitation. Intramolecular rotation around the vinyl moiety plays an important role in the whole photophysical process in addition to the electronic properties of the peripheral substituents. In dilute solutions, DSA derivatives possess a twisted structure in the ground state that eventually relaxes to a planar structure within picoseconds. The fluorescence process is dominated by the relaxed excited state, and the quantum yield is affected by competition between the nonradiative and radiative deactivations. The enhanced fluorescence of the molecular aggregates originates from the optically allowed S1–S0 transition together with the suppressed nonradiative deactivation via molecular stacking. These findings provide an in-depth understanding of the origin of the aggregation enhanced emission process, and may be applicable for the fine design of DSA based molecules with enhanced fluorescence and novel structures beyond DSA.

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Abstract

Abstract