Novel pyrene-and anthracene-based Schiff base derivatives P1 and A1 were synthesized via a one-pot reaction and utilized as fluorescence turn-on sensors towards Cu 2+ and Fe 3+ ions, respectively, and for aggregation induced emissions (AIEs). P1 in CH 3 CN and A1 in THF illustrated the fluorescence turn-on sensing towards Cu 2+ and Fe 3+ ions, respectively, via chelation enhanced fluorescence (CHEF) through excimer (P1-P1* and A1-A1*) formation. The 2 : 1 stoichiometry of the sensor complexes (P1 + Cu 2+ and A1 + Fe 3+ ) were calculated from Job plots based on UV-Vis absorption titrations. In addition, the binding sites of sensor complexes (P1 + Cu 2+ and A1 + Fe 3+ ) were well established from the 1 H NMR titrations and supported by the fluorescence reversibility by adding metal ions and PMDTA sequentially.The detection limits (LODs) and the association constant (K a ) values of P1 + Cu 2+ and A1 + Fe 3+ sensor responses were calculated by standard deviations, linear fittings and from their fluorescence binding isotherms. More importantly, P1 + Cu 2+ and A1 + Fe 3+ sensors were found to be active in wide ranges of pHs (1-14 and 2-14, respectively). Moreover, the time effect along with the enhancements of quantum yield (F) and time resolved photoluminescence (TRPL) decay constant (s) towards sensor responses were investigated. Similarly, P1 in CH 3 CN and A1 in THF showed AIEs by increasing the aqueous media concentration from 0% to 90%, with altered fluorescence peak shifts (red and blue shifts, respectively). As well as s value enhancements, the F values of 0.506 and 0.567 (with 630-and 101-fold enhancements) were acquired for P1 in CH 3 CN : H 2 O (20 : 80) and A1 in THF : H 2 O (40 : 60), respectively.

This manuscript describes the bulk synthesis of shape persistent two-dimensional (2D) polymers using the self-assembly of rigid precursor molecules into bilayers. A precursor was synthesized with a structure that encodes for the necessary molecular recognition events to form bilayers with intemal orientational order. These events include homochiral interactions and confine reactive functions to planes leading to covalent stitching of flat polymers. The resulting molecular objects have a monodisperse thickness of 5 nm and polydisperse planar dimensions on the order of hundreds or thousands of nanometers. One of the stiching reactions, the oligomerization of acrylate groups to form an all-carbon backbone, is catalyzed by the presence of dipolar stereocenters 13 atoms away from the double bond. These enantiomerically enriched stereocenters are substituted by nitrile groups which react to generate the second stitching backbone of the plate-shaped molecules. A computer simulation indicates that 2D polymers of molar mass in the range of millions can be formed with extremely short stitching backbones provided planar confinement of functions is achieved by molecular recognition events. "Bulk" syntheses of shape persistent 2D polymers which do not require extemal boundaries to confine monomers into 2D spaces may lead to many interesting advanced materials.

A novel amphiphilic aggregation-induced emission (AIE) copolymer, that is, poly(NIPAM-co-TPE-SP), consisting of N-isopropylacrylamide (NIPAM) as a hydrophilic unit and a tetraphenylethylene-spiropyran monomer (TPE-SP) as a bifluorophoric unit is reported. Upon UV exposure, the close form of non-emissive spiropyran (SP) in poly(NIPAM-co-TPE-SP) can be photo-switched to the open form of emissive merocyanine (MC) in poly(NIPAM-co-TPE-MC) in an aqueous solution, leading to ratiometric fluorescence of AIEgens between green TPE and red MC emissions at 517 and 627 nm, respectively, via Förster resonance energy transfer (FRET). Distinct FRET processes of poly(NIPAM-co-TPE-MC) can be observed under various UV and visible light irradiations, acid-base conditions, thermal treatments, and cyanide ion interactions, which are also confirmed by theoretical studies. The subtle perturbations of environmental factors, such as UV exposure, pH value, temperature, and cyanide ion, can be detected in aqueous media by distinct ratiometric fluorescence changes of the FRET behavior in the amphiphilic poly(NIPAM-co-TPE-MC). Moreover, the first FRET sensor polymer poly(NIPAM-co-TPE-MC) based on dual AIEgens of TPE and MC units is developed to show a very high selectivity and sensitivity with a low detection limit (LOD = 0.26 μM) toward the cyanide ion in water, which only contain an approximately 1% molar ratio of the bifluorophoric content and can be utilized in cellular bioimaging applications for cyanide detections.

A series of soluble donor-acceptor conjugated polymers comprising of phenothiazine donor and various benzodiazole acceptors (i.e., benzothiadiazole, benzoselenodiazole, and benzoxadiazole) sandwiched between hexyl-thiophene linkers were designed, synthesized, and used for the fabrication of polymer solar cells (PSC). The effects of the benzodiazole acceptors on the thermal, optical, electrochemical, and photovoltaic properties of these low-bandgap (LBG) polymers were investigated. These LBG polymers possessed large molecular weight (M n ) in the range of 3.85À5.13 Â 10 4 with high thermal decomposition temperatures, which demonstrated broad absorption in the region of 300À750 nm with optical bandgaps of 1.80À1.93 eV. Both the HOMO energy level (À5.38 to À5.47 eV) and LUMO energy level (À3.47 to À3.60 eV) of the LBG polymers were within the desirable range of ideal energy level. Under 100 mW/cm 2 of AM 1.5 white-light illumination, bulk heterojunction PSC devices containing an active layer of electron donor polymers mixed with electron acceptor [6,6]-phenyl-C 61 -butyric acid methyl ester (PC 61 BM) or [6,6]-phenyl-C 71butyric acid methyl ester (PC 71 BM) in different weight ratios were investigated. The best performance of the PSC device was obtained by using polymer PP6DHTBT as an electron donor and PC 71 BM as an acceptor in the weight ratio of 1:4, and a power conversion efficiency value of 1.20%, an open-circuit voltage (V oc ) value of 0.75 V, a short-circuit current (J sc ) value of 4.60 mA/cm 2 , and a fill factor (FF) value of 35.0% were achieved. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: [4823][4824][4825][4826][4827][4828][4829][4830][4831][4832][4833][4834] 2010

Sonodynamic therapy (SDT), which induces activation of sonosensitizers in cancer cells through ultrasound irradiation, has emerged as an alternative and promising noninvasive therapeutic approach to kill both superficial and deep parts of tumors. In this study, mesoporous silica (MSN) grown on reduced graphene oxide nanosheet (nrGO) capped with Rose Bengal (RB)-PEG-conjugated iron-oxide nanoparticles (IONs), nrGO@MSN-ION-PEG-RB, was strategically designed to have targeted functionality and therapeutic efficacy under magnetic guiding and focused ultrasound (FUS) irradiation, respectively. The singlet oxygen produced by ultrasound-activated RB and the ultrasound-induced heating effect was enhanced by rGO and IONs, which improved the cytotoxic effect in cancer cells. In an animal experiment, we demonstrated that the combination of sonodynamic/hyperthermia therapy with magnetic guidance using this nanocomposite therapeutic agent can produce remarkable efficacious therapy in tumor growth inhibition. Furthermore, the combination effect induced by FUS irradiation produces significant damage to both superficial and deep parts of the targeted tumor.