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• An AIE active anthracene-based Schiff base probe ' AP' is firstly reported as Cu2+ sensor. • AP has negligible interfering effect on Cu2+ detection with nanomolar LOD. • AP - AP * in AIE and AP − Cu2+ − AP * excimer formation is established from UV/PL, DFT and 1H NMR titration debriefings. • Crystalline and nanostructural features of AIE and sensors are authorized by PXRD, SEM, TEM and DLS studies. • Proposed method is validated by cellular imaging and real water recovery interrogations. An aggregation induced emission (AIE) active anthracene-based Schiff base probe "(2-((anthracen-9-ylmethylene) amino) phenol); AP " was synthesized via one-pot reaction and utilized in "turn-on" detection of Cu2+ ions. Ultraviolet–visible and photoluminescence (UV–vis/PL) interrogations confirm the AIE between 0 and 99 % water fraction (f w) and high selectivity of AP to Cu2+. PL studies establish the linear regression of Cu2+ between 0 and 24 µM with a detection limit (LOD) of 53.2 nM. The Job plot and high-resolution mass (HR-mass) data affirm 2:1 stoichiometry and the association constant (K a) value appraised as 1.88 × 10−4 M−2. Time-resolved photoluminescence (TRPL) studies reveal decay kinetics of AIE, Cu2+ sensors and complex's reversibility. Moreover, 1H NMR titration and density functional theory (DFT) investigations identify the binding mode, π-π stacking in AIE, AP − Cu2+ − AP * excimer formation, band gap variations and involvement of photoinduced electron transfer (PET) and chelation enhanced fluorescence (CHEF) mechanism. Crystallinity and nanostructural variations of AIE and Cu2+ sensors are investigated by using powder-X-ray diffraction (PXRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and dynamic light scattering (DLS). AIE and Cu2+ sensory method are validated by MDA-MB-231 cellular imaging studies. Finally, real water-based titrations show nanomolar LODs and recoveries > 97 % with RSDs < 3.5 %. [ABSTRACT FROM AUTHOR]

Abstract A newly designed 2-(2-Aminophenyl)-1 H -benzimidazole integrated anthracene/pyrene derivatives as efficient chemosensors were synthesized. The probes N-(anthracen-9-ylmethylene)-2-(1 H -benzo[d]imidazol-2-yl)aniline (ANP) and N-(pyren-1-ylmethylene)-2-(1 H -benzo[d]imidazol-2-yl)-aniline (PYP) exhibited high selectivity and sensitivity towards Al3+ ion over other interfering and competing cations in aqueous solution. Job's plot analysis reveals that the interaction of ANP/PYP with Al3+ was 1:1 binding stoichiometry. The detection limit of probes ANP and PYP for Al3+ ions were found to be 1.85 × 10−7 M and 1.08 × 10−7 M, respectively. The DFT/TD-DFT calculations have also been revealed that the ICT mechanism is responsible for the observed photophysical changes. Moreover, the probes ANP and PYP were applicable to image intracellular Al3+ ions in living cells via confocal fluorescence microscopy technique. Graphical abstract Image 1 Highlights • New anthracene and pyrene bearing Schiff base derivatives (ANP and PYP) were designed and synthesized. • The probes ANP and PYP served as an efficient fluorescent chemosensor towards Al3+ with high selectivity. • The 1:1 binding stoichiometry of the sensor ANP/PYP with Al3+ was established. • Reversibility of the chemosensor ANP/PYP was proved by experiments with EDTA. • ANP/PYP was successfully applied to fluorescence imaging of Al3+ in living cells. [ABSTRACT FROM AUTHOR]

Singlet oxygen plays an important role in cancer chemotherapy and biology of reactive oxygen species. In recent years, there are some reports of selective fluorescent probes for detection and imaging of singlet oxygen but the existing probes have some major drawbacks including complicated synthetic routes, poor fluorescence enhancement effects. We report herein that anthracenylmethyl modified non-fluorescent derivatives of fluorescein and rhodamine-6G can reacts with 1 O 2 , which resulted in C C bond cleavage that detach anthracene unit from the fluorophores resulting in strong fluorescence enhancement. These probes exhibit high selectivity and sensitivity in detection and imaging of 1 O 2 in chemical and in living cells. Our approach makes it simple and flexible for development of reaction-based 1 O 2 fluorescent probes for broad application in chemical, biomedical, and environmental sciences. [ABSTRACT FROM AUTHOR]

A simple triazole bridged molecular probe containing anthracene and quinoline moieties has been designed and synthesized as a fluorescent molecular probe ( 7 ). The photophysical behavior of the probe 7 has been examined and tested for the recognition of ions in partial aqueous medium and HeLa cell. The probe 7 has shown strong affinity for Hg 2+ and has been utilized to develop a stable ensemble, 7·Hg 2 + . The ensemble, 7·Hg 2+ upon interaction with different class of anions showed high affinity for cyanide with ∼16 fold fluorescence enhancement and high limit of detection, 1.25 μM. The live cell imaging studies showed that ensemble 7·Hg 2+ is capable to detect CN − intracellularly. The analytical applicability of the probe for Hg 2+ and CN − has been tested on the test paper strips. Additionally, the naked eye sensitive “ On–Off–On ” switching behavior of 7 has been utilized to mimic the function of a sequential logic circuit at molecular level. The 1 H NMR titration, ESI-MS spectroscopy and DFT calculation confirms the binding behavior between 7 and Hg 2+ . [ABSTRACT FROM AUTHOR]

[Display omitted] • The probe APDA exhibited sensitivity for Cu2+ ion in 80% aqueous acetonitrile medium. • Probe APDA shows dual emission due to TICT and ICT states. • The hydrolysis of imine bond of probe APDA in the presence of Cu2+ ion, rejuvenate aldehyde derivative. • The probe APDA has been applied on test paper strip to detect Cu2+ ion with naked-eye sensitive response. The work reported herein describes photophysical behavior of a new fluorescent probe APDA. The probe exhibited sensitivity for Cu2+ ion in 80% aqueous acetonitrile medium. Probe shows dual emission due to TICT and ICT states and upon interaction with different metal ions Cu2+ induces hydrolysis of imine bond to rejuvenate aldehyde derivative with ratiometric "turn–On" fluorescence response, through ICT state while emission due to TICT state get diminished. Similarly, the synthesized model compound ADA under similar experimental condition supported hydrolysis of imine bond in the presence of copper. Jobs plot analysis, based on emission titration data suggested a 1:1 binding stoichiometry between probe APDA and Cu2+ ion. The limit of detection (LOD) was found to be 4.4 × 10-8 M (44 nM). The probe has been applied on test paper strip to detect Cu2+ ion with naked-eye sensitive response. Also, the cell imaging studies revealed the potential applicability of probe to detect Cu2+ ion in live cells. The mechanism of sensing was confirmed by 1H, 13C NMR, FTIR and mass spectrometry data analysis. [ABSTRACT FROM AUTHOR]

Aptamer-functionalized fluorescent silver nanoclusters (Ag NCs) possessing specific recognition ability of aptamer and fluorescence emissions have been developed for applications in biorelated areas. However, only one color emission hampered their further use in multiplexed analysis. To address this issue, AS1411 aptamer-tagged Ag NCs with green color emissions and MUC 1 aptamer-tagged Ag NCs with yellow color emissions were synthesized by one-pot approach in this work. With the rational design of the DNA template and optimization of the synthetic buffer, as well as the NaBH 4 -to-Ag + ratio, the growth time and purity of the obtained aptamer-functionalized Ag NCs were improved. Under the optimal conditions, the quantum yields of AS1411 aptamer-functionalized green Ag NCs and MUC 1 aptamer-functionalized yellow Ag NCs were 20.33% and 8.65% with 9,10-diphenyl anthracene and fluorescein as the reference standards, respectively. The green and yellow emission properties of Ag NCs were related to the surface oxidation states of the Ag NCs. Furthermore, the binding ability of AS1411 aptamer and MUC 1 aptamer to cancer cells enabled specific cellular imaging. Aptamer-functionalized Ag NCs with multicolor emissions could broaden the applications of Ag NCs in multiplexed analysis and multicolor imaging of tumor cells, especially with the selection of more targeted aptamers. [ABSTRACT FROM AUTHOR]

A new asymmetric fluorescent dye of the 4,4-difluoro-4-bora-3a,4a-diaza- s -indacene (BODIPY) class was prepared by fusing an anthracene unit to the “zig-zag” edge of the BODIPY core by an FeCl 3 -mediated oxidative cyclodehydrogenation reaction and the photophysical properties of the new BODIPY analogue were investigated. The anthracene-fused BODIPY exhibits significant bathochromic shifts in both absorption and fluorescence maxima compared with a related non-fused BODIPY. In addition, the anthracene-fused BODIPY exhibited a small energy gap (1.81 eV), large Stokes shift and high photostability. Especially, the emission of the dye extended into the deep red (∼640 nm) region. The extensive π conjugation is responsible for the red-shifted emission. Moreover, the dye emits strong saturated, red fluorescence with a quantum yield of 40% and an enlarged Stokes shift of 1425 cm −1 (53 nm) in CHCl 3 , which can be used to image living cells by fluorescence microscopy. Cell imaging experiments demonstrated its potential application as a probe in bioorganisms due to its excellent imaging contrast. [ABSTRACT FROM AUTHOR]

The construction of highly efficient artificial light-harvesting systems in aqueous solutions is still challenging. Herein, we reported a new light-harvesting system based on the supramolecular combination of twisted cucurbit[15]uril (t Q[15]), cucurbit[10]uril (Q[10]), and an anthracene derivative (APy) with aggregation-induced emission (AIE) properties. The Q[ n ]-based linear supramolecular polymer, APy@ t Q[15]@Q[10], was constructed through a two-step assembly strategy. Subsequently, a highly efficient artificial light-harvesting system with relatively high antenna effect and energy transfer efficiency was successfully constructed through non-covalent interactions between Rhodamine B (RB, acceptor) and the APy@ t Q[15]@Q[10] (donor). The resulting system was compatible with HeLa cells and could be used for live-cell imaging in the red channel. This supramolecular assembly strategy has not only produced a highly efficient light-harvesting system but also expands the application of Q[ n ]s in the biomedical field. [Display omitted] • A new light-harvesting system based on the largest twisted cucurbit[15]uril and cucurbit[10]uril. • AIE compound fabricated a light-harvesting system with RB in a two-step self-assembly strategy. • The constructed light-harvesting system further applied into the cell imaging in red channel. [ABSTRACT FROM AUTHOR]

A new probe based on anthracene-xanthene dyes for detecting Hg2+ was designed and the detailed mechanism was researched systematically. [Display omitted] • A colorimetric and fluorometric probe 1 based on anthracene and xanthene was synthesized. • 1 having highly selective recognition of Hg2+ by FRET mechanism. • The detection mechanism had been verified by NMR, ESI-MS, and HPLC spectra. • The probe can detect Hg2+ in living cells. 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 Hg2+ in the CH 3 CN/H 2 O (1/1, v/v) system, with a fast response time (less than 30 s); The fluorescent color changed from purple to orange and the solution visible to the naked-eye changed from colorless to pink. The Pseudo-Stokes shift was 174 nm upon addition of Hg2+. The limit of detection (LOD) was calculated to be 0.81 μM and 0.38 μM according to fluorescence and UV/vis measurements, respectively. Furthermore, a possible mechanism for the detection of Hg2+ by probe 1 was verified by using 1H NMR, ESI-MS, and HPLC spectra. Meanwhile, probe 1 was successfully used for cell imaging for the detection of Hg2+ in living cells. [ABSTRACT FROM AUTHOR]

We have synthesized a new probe 5-((anthracen-9-ylmethylene) amino)quinolin-10-ol ( ANQ ) based on anthracene platform. The probe was tested for its sensing behavior toward heavy metal ions Hg 2+ , Pb 2+ , light metal Al 3+ ion, alkali, alkaline earth, and transition metal ions by UV–visible and fluorescent techniques in ACN/H 2 O mixture buffered with HEPES (pH 7.4). It shows high selectivity toward sensing Pb 2+ /Al 3+ metal ions. Importantly, 10-fold and 5- fold fluorescence enhancement at 429 nm was observed for probe upon complexation with Pb 2+ and Al 3+ ions, respectively. This fluorescence enhancement is attributable to the prevention of photoinduced electron transfer. The photonic studies indicate that the probe can be adopted as a sensitive fluorescent chemosensor for Pb 2+ and Al 3+ ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mitochondria-targeted probes P-Py and P-An were designed by conjugating anthracene and pyrene with pyridinium. • P-Py and P-An served as efficient fluorescent sensors towards bisulfite in aqueous solutions. • P-Py also exhibited viscosity responses with a Stokes shift of 140 nm. • The dual-detection behaviors of P-Py were successfully conducted in HeLa cells. We have designed two mitochondria targetable probes P-Py and P-An by the π-conjugation of polyaromatic hydrocarbons (pyrene vs. anthracene) with 4-dimethylamino pyridinium. They present an amphiphilic property with excellent solubility in the common polar and non-polar solvents. Both of them demonstrated a significant fluorescence response to bisulfite in Tris-HCl buffer solutions (5 mM, pH = 7.4). By a combination of fluorescence, UV–vis, time-resolved emission, 1H NMR, and ESI-MS, their sensing mechanisms have been elaborated to be a Michael addition. Notably, P-Py also exhibits a sensitivity to the viscosity change with a Stokes shift of 140 nm, due to the restriction of C–C bond rotation. By taking advantages of its good water solubility, low toxicity, and high mitochondrial target, the dual responses of P-Py to exogenous SO 2 derivatives and viscosity change in mitochondria were explored by confocal fluorescence microscopy. [ABSTRACT FROM AUTHOR]

Singlet oxygen (1O 2), as a highly reactive oxygen species, plays an important role in the physical, chemical and biomedical fields, especially during photodynamic therapy (PDT) process. In this work, two iridium(III) complexes containing an anthracene unit in their diimine ligand were designed and synthesized to monitor 1O 2 in living cells. The complexes were weakly emissive owing to the photoinduced electron transfer process, but exhibited intense luminescence upon capturing 1O 2 , resulting from the formation of the corresponding endoperoxide analogues. The remarkable turn-on luminescence response was specific toward 1O 2 and in preference to other reactive oxygen species. The utilization of one of the complexes for imaging 1O 2 in living cells has also been demonstrated using three different cells lines. Cells incubated with the complexes were hardly emissive. Further light irradiation at 475 nm triggered intracellular emission turn on, indicative of the production of 1O 2 photochemically. The emissive pattern was well colocalized with commercially available MitoTracker, suggesting the potential applications of the complexes for imaging mitochondria 1O 2. The 1O 2 capturing properties rendered the complexes low photocytotoxicity since 1O 2 -caused oxidative damage toward cellular molecules and structures was inhibited. We have developed two mitochondria-targeted iridium(III) complexes, which exhibit specific luminescence enhancement in response to 1O 2 and reduced phototoxicity toward living cells. Unlabelled Image • Two iridium(III) complexes containing an anthracene unit are synthesized. • The complexes exhibited phosphorescence turn-on toward 1O 2. • The complexes are used for 1O 2 detection in solution and 1O 2 imaging in living cells. • The complexes exhibited low photocytotoxicity toward cells. [ABSTRACT FROM AUTHOR]

A new anthracene-based chemosensor An3 that showed high selectivity and sensitivity towards Zn2+ cation has been prepared. Experimental and theoretical results supported 1:1 and 1:2 binding stoichiomietry between An3 and Zn2+. An3 was applied in fluorescent imaging of Zn2+ in living cells and zebrafish. • Anthacene-based chemosensor An3 showed high specificity for Zn2+ detection. • Low detection limit of An3 for Zn2+ was determined to be 36 nM. • An3 was successfully applied in in vitro and in vivo imaging of Zn2+. • Theoretical calculations supported 1:1 and 1:2 binding ratio between An3 and Zn2+. A new fluorescent chemosensor (An3) bearing anthracenyl rings was designed and developed for detection of Zn2+. Addition of Zn2+ into An3 gave rise to a fluorescent turn-on response at 424 nm whereas Al3+, Cd2+, Co2+, Cu2+, K+, Mg2+, Zn2+, Ca2+, Fe3+, Mn2+, Ni2+, Pb2+, and Hg2+ did not induce any emission intensity enhancement. Furthermore, the probe exhibited high selectivity toward Zn2+ and a very low detection limit (36 nM) based on chelation-enhanced fluorescence. Theoretical calculations revealed the possible formation of 1:1 and 1:2 complexes between An3 and Zn2+. In bioimaging experiments, the chemosensor displayed low cytotoxicity and good biocompatibility, rendering it an effective tool for fluorescent visualization of Zn2+ in living cells and zebrafish models. [ABSTRACT FROM AUTHOR]

Three new symmetrical 9,10-dithienylanthracene (DTA) derivatives, including 9,10-bis-(4-(4-methoxyphenyl)-5-methylthiophene-2-yl)anthracene (BMPTA), 9,10-bis-(5-methyl-4-phenylthiophene-2-yl)anthracene (BPTA), and 9,10-bis-(4-(4-cyanophenyl)-5-methylthiophene-2-yl)anthracene (BCPTA), with excellent aggregation-induced emission (AIE) behaviors had been designed and synthesized successfully. Crystal BMPTA and BPTA had nonplanar conformations because of the multiple intermolecular hydrogen bonding interaction between the adjacent molecules, which restricted their intramolecular rotation and enabled them to emit intensely. Additionally, both BMPTA and BPTA exhibited reversible mechanofluorochromic (MFC) performance by grinding-fuming, which was systematically investigated with powder X-ray diffraction (XRD), differential scanning calorimetry (DSC) and photoluminescent (PL) lifetime. The results showed that substituent groups had significant influence on their molecular packing, MFC and AIE properties. Furthermore, these DTA luminogens could be applied in cell imaging as fluorochrome. Three new symmetric 9, 10-dithienylanthracene (DTA) derivatives with remarkable aggregation-induced emission (AIE) characteristics have been synthesized. Their properties, including AIE, crystal structures, mechanofluorochromic, and cell imaging were investigated. Image 1 • Three new DTA derivatives with excellent AIE behavior had been designed and synthesized. • The crystal structures of BMPTA and PTA showed nonplanar conformations and reversible MFC performance by grinding-fuming. • All of them could be applied in cell imaging as fluorochrome. [ABSTRACT FROM AUTHOR]

• A simple anthracene-based fluorescent "on-off" probe was developed for Fe3+. • The transformation from anthraldehyde dimethyl acetal to anthraldehyde was achieved. • The probe displayed good performance on living cell imaging. A simple fluorescent probe L for Fe3+ was easily synthesized based on anthracene. Among the various metal ions including Fe2+, this probe exhibited high sensitivity and good selectivity toward Fe3+ with turn-off fluorescence mode in DMSO-HEPES buffer solution (20 mM, pH = 7.0, 1:1 (v/v)). When adequate Fe3+ ion was added into the solution of probe L , its molecular structure transferred from anthraldehyde dimethyl acetal to anthraldehyde, resulting in fluorescence quenching with a low detection limit of 3.08 μM. 1H NMR spectra and TLC analysis further supported this concept. Finally, this probe was successfully applied in bioimaging. [ABSTRACT FROM AUTHOR]