1,127 research outputs found

    Ion sensing coupled to resonance energy transfer: A highly selective and sensitive ratiometric fluorescent chemosensor for Ag(I) by a modular approach

    No full text
    We report a novel dimeric boradiazaindacene dye which can be converted in one step to an efficient resonance energy transfer (RET) dyad. In addition, if this modification is done with appropriate ligands, RET can be coupled to ion sensing. The utility of this approach is demonstrated in a highly selective, emission ratiometric chemosensor for Ag(I)

    Difluorobora-s-diazaindacene dyes as highly selective dosimetric reagents for fluoride anions

    No full text
    Difltiorobora-s-diazaindacene derivatives are shown to report fluoride ions selectively in acetone solutions; both absorption and emission characteristics are drastically altered, and as a result, (his hitherto unknown reaction transforms the BODIPY(R) class of dyes into highly selective chromogenic and dual channel fluorogenic reagents for fluoride

    Three-point recognition and selective fluorescence sensing of L-DOPA

    No full text
    A phenylboronic acid derivative of a well-known dye (Lucifer yellow) recognizes L-DOPA through a combination of reversible esterification, charge transfer, and electrostatic interactions. The selective recognition event is signaled by a drop in the emission intensity of the fluorescent chemosensor

    Linker Linked CAGE Polymers and Method for Preparing the Same

    No full text
    본 발명은 CAGE와 링커가 연결된 고분자 및 그 제조방법에 관한 것으로, 더욱 상세하게는, 이산화탄소 흡착능이 우수한 CAGE와 링커가 연결된 고분자와 그 제조방법 및 상기 CAGE와 링커가 연결된 고분자를 이용한 이산화탄소 흡착 또는 포집 방법에 관한 것이다. 본 발명에 따르면, CAGE와 링커가 연결된 고분자는 CAGE에 비해 비표면적이 증가하고, 이산화탄소 흡착능, 흡착량 및 흡착 선택능이 우수하므로, 연소 후 배기 가스에 포함된 이산화탄소 흡착 및 포집제로 유용하다

    Signal ratio amplification via modulation of resonance energy transfer: Proof of principle in an emission ratiometric Hg(II) sensor

    No full text
    Boradiazaindacene dyads designed as energy transfer casettes can be modified to signal cation concentrations ratiometrically. If the energy transfer efficiency is increased via changing spectral overlap on cation binding, an enhancement of emission signal ratios can be obtained. A larger range of ratios results in highly improved sensitivity to analyte concentrations. We demonstrate this approach in a de novo design of a novel and highly selective ratiometric chemosensor for Hg(II) ions

    Thinking Outside the Cage: Controlling the Extrinsic Porosity and Gas Uptake Properties of Shape-Persistent Molecular Cages in Nanoporous Polymers

    No full text
    We present a new strategy to introduce local-order into amorphous nanoporous polymers using shape-persistent organic cage compounds as molecular building blocks in the synthesis of porous cage frameworks (pCAGEs) without any metal catalyst under environmentally benign conditions. We have demonstrated that by varying the size and dimension of the organic linkers extrinsic porosity of organic cages within nanoporous polymers can be controlled, thus allowing us to tune the surface area and gas uptake properties of amorphous pCAGEs. pCAGEs (SA(BET) = 628.7-844.3 m(2) g(-1)) revealed significantly high CO, uptake capacities (up to 4.21 mmol g(-1) at 1 bar, 273 K) with prominent CO2/N-2 IAST selectivities (up to 100). Unlike previously reported triazine-based polymers, pCAGEs showed exceptional isosteric heats of adsorption (Q(st)) values up to 42.9 kJ mol(-1) for CO2 at high loading. We attribute the high affinity of CAGE toward CO2 to the presence of a "cage effect" arising from ultramicroporosity (intrinsic porosity) of CAGE monomers. To prove the cage effect, we have synthesized a control polymer incorporating half-CAGEs as monomeric units. The resulting polymer showed substantially lower Q(st) values compared to the CAGE and pCAGEs indicating the presence of the cage effect. In addition, the control over the surface area in the case of control polymer was lost completely, thus showing the importance of CAGE monomers as building blocks and the resulting local-order

    Effective PET and ICT switching of boradiazaindacene emission: A unimolecular, emission-mode, molecular half-subtractor with reconfigurable logic gates

    No full text
    We report a unimolecular system functioning as a combinatorial logic circuit for half-subtractor. The emission characteristics can be modulated by chemical inputs, and when followed at two different wavelengths, two functionally integrated logic gates XOR and INHIBIT are obtained. Both logic gates function in the emission mode, and with very large differences in the signal intensity allowing unequivocal assignment of logic-0 and logic-1

    Cation modulation of carbonyldipyrrinone (CDP) fluorescence: emission-ratiometric sensing of calcium

    No full text
    Optically dilute solutions of 2,3,7,8-tetraethyl-N,N'-carbonyldipyrrinone displays an absorbance peak at 401 nm and an emission peak at 493 nm in acetonitrile. The two carbonyl groups in the structure seems to be optimally placed for cation coordination, and when calcium ions are added in the form of a perchlorate salt, a remarkable bathochromic change in the absorption and emission spectrum takes place: the absorption peak shifts by 24 nm and the emission peak shifts by 49 nm towards the red end of the visible spectrum. The shift in the emission spectrum allows wavelength ratiometric assessment of calcium concentration. In addition, the response is highly selective with respect to the cations added

    Novel fluorescent chemosensor for anions via modulation of oxidative PET: a remarkable 25-fold enhancement of emission

    No full text
    The fluorescence emission intensity of the 1:1 Zn(II) complex of a doubly boradiazaindacene (BODIPY) substituted bipyridyl ligand is highly sensitive to anion coordination to the metal center. Oxidative PET, which is responsible for the quenching of the fluorescence in the complex is effectively inhibited by anion coordination, leading to a 25-fold enhancement of the emission intensity. (C) 2003 Published by Elsevier Ltd
    corecore