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Wei Huang - One of the best experts on this subject based on the ideXlab platform.
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elucidating the excited state dynamics behavior in near infrared BODIPY Dye and aggregates toward biophotonics
Science China-chemistry, 2020Co-Authors: Xiaofei Miao, Wei Huang, Quli Fan, Haojie Tao, Yonghui PanAbstract:Photo-induced excited-state dynamics within organic materials fundamentally determine their photophysical properties for various applications, and thus understanding the primary excited-state dynamics behavior is of fundamental and practical significance. Until recently, the excited-state dynamics of organic materials towards biophotonics have been rarely studied, although numerous endeavors have been devoted to the design of organic materials for biophotonics. Herein, various spectroscopy technologies including femtosecond transient absorption (fs-TA) spectroscopy clearly reveal a totally different excited state dynamics behavior within BODIPY monomer (2B-BDP Dye) and aggregates (2B-BDP NPs), indicating strongly morphology dependent character. 2B-BDP Dye undergoes an ultrafast conversion from S1 to intramolecular charge transfer (ICT) state for subsequent photoluminescence (PL) and nonradiative (NR) decay, while 2B-BDP NPs show an accelerated excited-state deactivation mainly through S1→S0 NR decay. The potential bioapplications based on the corresponding excited state dynamics behavior are discussed together with experimental results. Interestingly, the accelerated NR decay in 2B-BDP NPs does not yield a stronger photoacoustic (PA) signal than that in 2B-BDP Dye, which violates the conventional wisdom that faster NR decay would benefit the photothermal effects for better photoacoustic imaging (PAI). These insightful and fundamental observations of the excited-state dynamics may contribute an alternative approach at the molecular level towards the future design of functional BODIPY-based organic molecules with desirable performances.
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engineering lysosome targeting BODIPY nanoparticles for photoacoustic imaging and photodynamic therapy under near infrared light
ACS Applied Materials & Interfaces, 2016Co-Authors: Bing Hou, Hui Zhao, Rongcui Jiang, Lei Zhang, Yufu Tang, Quli Fan, Wei HuangAbstract:Developing lysosome-targeting organic nanoparticles combined with photoacoustic imaging (PAI) and photodynamic therapy (PDT) functions toward personalized medicine are highly desired yet challenging. Here, for the first time, lysosome-targeting BODIPY nanoparticles were engineered by encapsulating near-infrared (NIR) absorbed BODIPY Dye within amphiphilic DSPE-mPEG5000 for high-performing lysosomal PAI and acid-activatable PDT against cancer cells under NIR light.
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excellent BODIPY Dye containing dimesitylboryl groups as pet based fluorescent probes for fluoride
Journal of Physical Chemistry C, 2011Co-Authors: Huibin Sun, Shujuan Liu, Qiang Zhao, Xiaochen Dong, Xin Mou, Hui Ying Yang, Wei HuangAbstract:A highly selective fluorescent probe BBDPB for F– was realized on the basis of the boron-dipyrromethene (BODIPY) Dye containing two dimesitylboryl (Mes2B) moieties. The fluorophore displays highly ...
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an excellent BODIPY Dye containing a benzo 2 1 3 thiadiazole bridge as a highly selective colorimetric and fluorescent probe for hg2 with naked eye detection
New Journal of Chemistry, 2011Co-Authors: Huibin Sun, Shujuan Liu, Nannan Song, Qiang Zhao, Wei HuangAbstract:An excellent red-emissive BODIPY Dye containing a benzo[2,1,3]thiadiazole bridge was synthesized, and its sensing ability toward metal cations was investigated in detail. It can work as a highly selective probe for Hg2+ detected by the naked eye, with evident solution color and photoluminescence changes.
Raymond Ziessel - One of the best experts on this subject based on the ideXlab platform.
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a deep purple grey thiophene benzothiadiazole thiophene BODIPY Dye for solution processed solar cells
New Journal of Chemistry, 2014Co-Authors: Antoine Mirloup, Nicolas Leclerc, Sandra Rihn, Thomas Bura, Rony Bechara, Anne Hebraud, Patrick Leveque, Thomas Heiser, Raymond ZiesselAbstract:In this work we explore the synthesis of an extended 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene Dye (BODIPY) engineered from thiophene–benzothiadiazole–thiophene modules linked in the 3,5-substitution positions. We found that this highly soluble Dye absorbs up to 800 nm in solution and up to 900 nm in thin films. An effective charge transfer absorption band was found at around 479 nm. The hybrid Dye emits at 778 nm with a quantum yield of about 6%. Similar electrochemical and optical gaps were determined about 1.36 eV. When deposited in thin films the Dye exhibits an ambipolar nature with well-balanced hole and electron mobilities. Bulk heterojunction solar cells based upon this Dye blended with [6,6]phenylC61or71butyricacid methylester (PC61BM or PC71BM) provide a power conversion efficiency of about 1.26% upon a mild thermal annealing.
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A hybrid bis(amino-styryl) substituted BODIPY Dye and its conjugate diacid: synthesis, structure, spectroscopy and quantum chemical calculations.
Physical Chemistry Chemical Physics, 2014Co-Authors: Adela Nano, Pascal Retailleau, Jerry P Hagon, Anthony Harriman, Raymond ZiesselAbstract:A new type of fluorescent pH indicator has been developed whereby two dissimilar amino-styryl units are attached to a boron dipyrromethene (BODIPY) Dye. The photophysical properties of this hybrid Dye, and its simpler counterparts bearing only a single amino-styryl residue, depend on the polarity of the surrounding medium. Of the two terminal amines, DFT (B3LYP/6-31G**) calculations and spectroscopic measurements support the notion that julolidine is oxidised and protonated under milder conditions than is N,N-dimethylaniline. For the hybrid Dye, similar DFT calculations carried out for the mono-protonated analogues indicate that the julolidine residue is the stronger base while the resultant conjugate acid is the weaker one. Absorption and fluorescence spectroscopic titrations show that protonation of the hybrid Dye occurs in two well-resolved steps, whereby addition of the first proton introduces a thermodynamic barrier for entry of the second. In the hybrid Dye, the pKA values for the respective conjugate acids differ markedly from those derived for the mono-amino-styryl Dyes and display negative co-operativity. Effectively, this means that electronic interactions running along the molecular backbone make it more difficult, relative to the individual Dyes, to protonate both amino sites. As such, this Dye operates as a probe over an unusually wide pH range.
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length dependence for intramolecular energy transfer in three and four color donor spacer acceptor arrays
Journal of the American Chemical Society, 2009Co-Authors: Anthony Harriman, Laura J Mallon, Gilles Ulrich, Kristopher J Elliot, Alexandre Haefele, Raymond ZiesselAbstract:A series of donor−spacer−acceptor triads has been synthesized and fully characterized. Both donor and acceptor units are built from boron dipyrromethene (BODIPY) Dyes but they differ in their respective conjugation lengths, and thereby offer quite disparate optical properties. The spacer units comprise an oligomer of 1,4-phenylene-diethynylene repeat units and allow the boron−boron separation distance to be varied progressively from 18 to 38 A. A notable feature of this series is that each subunit can be selectively excited with monochromatic light. Highly efficacious electronic energy transfer (EET) occurs from the first-excited singlet state localized on the conventional BODIPY Dye to its counterpart resident on the expanded BODIPY-based nucleus, but the rate constant follows a nonlinear evolution with separation distance. Overall, the rate of EET falls by only a factor of 4-fold on moving from the shortest to the longest spacer. This shallow length dependence is a consequence of the energy gap between ...
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energy and charge transfer processes in a perylene BODIPY pyridine tripartite array
European Journal of Organic Chemistry, 2008Co-Authors: Mohammed A H Alamiry, Anthony Harriman, Laura J Mallon, Gilles Ulrich, Raymond ZiesselAbstract:A novel boron dipyrromethene (BODIPY) Dye has been synthesized in which the F atoms, usually bound to the boron center, have been replaced with 1-ethynylperylene units and a 4-pyridine residue is attached at the meso-position. The perylene units function as photon collectors over the wavelength range from 350 to 480 nm. Despite an unfavorable spectral overlap integral, rapid energy transfer takes place from the singlet-excited state of the perylene unit to the adjacent BODIPY residue, which is itself strongly fluorescent. The mean energy-transfer time is 7 ± 2 ps at room temperature. The dominant mechanism for the energy-transfer process is Dexter-type electron exchange, with Forster-type dipole–dipole interactions accounting for less than 10 % of the total transfer probability. There are no indications for light-induced electron transfer in this system, although there is evidence for a nonradiative decay channel not normally seen for F-type BODIPY Dyes. This new escape route is further exposed by the application of high pressure. The meso-pyridine group is a passive bystander until protons are added to the system. Then, protonation of the pyridine N atom leads to complete extinction of fluorescence from the BODIPY Dye and slight recovery of fluorescence from the perylene units. Quenching of BODIPY-based fluorescence is due to charge-transfer to the pyridinium unit whereas the re-appearance of perylene-based emission is caused by a reduction in the Forster overlap integral upon protonation. Other cations, most notably zinc(II) ions, bind to the pyridine N-atom and induce similar effects but the resultant conjugate is weakly fluorescent.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
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rapid energy transfer in cascade type BODIPY Dyes
Journal of the American Chemical Society, 2006Co-Authors: Anthony Harriman, Guillaume Izzet, Raymond ZiesselAbstract:Three new molecular dyads, comprising a bora-3a,4a-diaza-s-indacene (BODIPY) Dye linked to two aromatic polycycles via the boron center, have been synthesized and fully characterized. The polycyclic compounds are either pyrene or perylene, or a mixture of both. Whereas the absorption spectral profiles contain important contributions from each of the subunits, fluorescence occurs exclusively from the BODIPY fragment. Intramolecular excitation energy transfer is extremely efficient in each case, even though spectral overlap integrals for the pyrene-based system are modest. Although these polycycles are sterically congested, molecular dynamics simulations indicate that they are in dynamic motion, and this hinders proper computation of the orientation factors for Forster-type energy transfer. These new Dyes, especially the mixed polycycle system, greatly extend the range of excitation wavelengths that can be used for fluorescence microscopy.
Anthony Harriman - One of the best experts on this subject based on the ideXlab platform.
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A hybrid bis(amino-styryl) substituted BODIPY Dye and its conjugate diacid: synthesis, structure, spectroscopy and quantum chemical calculations.
Physical Chemistry Chemical Physics, 2014Co-Authors: Adela Nano, Pascal Retailleau, Jerry P Hagon, Anthony Harriman, Raymond ZiesselAbstract:A new type of fluorescent pH indicator has been developed whereby two dissimilar amino-styryl units are attached to a boron dipyrromethene (BODIPY) Dye. The photophysical properties of this hybrid Dye, and its simpler counterparts bearing only a single amino-styryl residue, depend on the polarity of the surrounding medium. Of the two terminal amines, DFT (B3LYP/6-31G**) calculations and spectroscopic measurements support the notion that julolidine is oxidised and protonated under milder conditions than is N,N-dimethylaniline. For the hybrid Dye, similar DFT calculations carried out for the mono-protonated analogues indicate that the julolidine residue is the stronger base while the resultant conjugate acid is the weaker one. Absorption and fluorescence spectroscopic titrations show that protonation of the hybrid Dye occurs in two well-resolved steps, whereby addition of the first proton introduces a thermodynamic barrier for entry of the second. In the hybrid Dye, the pKA values for the respective conjugate acids differ markedly from those derived for the mono-amino-styryl Dyes and display negative co-operativity. Effectively, this means that electronic interactions running along the molecular backbone make it more difficult, relative to the individual Dyes, to protonate both amino sites. As such, this Dye operates as a probe over an unusually wide pH range.
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length dependence for intramolecular energy transfer in three and four color donor spacer acceptor arrays
Journal of the American Chemical Society, 2009Co-Authors: Anthony Harriman, Laura J Mallon, Gilles Ulrich, Kristopher J Elliot, Alexandre Haefele, Raymond ZiesselAbstract:A series of donor−spacer−acceptor triads has been synthesized and fully characterized. Both donor and acceptor units are built from boron dipyrromethene (BODIPY) Dyes but they differ in their respective conjugation lengths, and thereby offer quite disparate optical properties. The spacer units comprise an oligomer of 1,4-phenylene-diethynylene repeat units and allow the boron−boron separation distance to be varied progressively from 18 to 38 A. A notable feature of this series is that each subunit can be selectively excited with monochromatic light. Highly efficacious electronic energy transfer (EET) occurs from the first-excited singlet state localized on the conventional BODIPY Dye to its counterpart resident on the expanded BODIPY-based nucleus, but the rate constant follows a nonlinear evolution with separation distance. Overall, the rate of EET falls by only a factor of 4-fold on moving from the shortest to the longest spacer. This shallow length dependence is a consequence of the energy gap between ...
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energy and charge transfer processes in a perylene BODIPY pyridine tripartite array
European Journal of Organic Chemistry, 2008Co-Authors: Mohammed A H Alamiry, Anthony Harriman, Laura J Mallon, Gilles Ulrich, Raymond ZiesselAbstract:A novel boron dipyrromethene (BODIPY) Dye has been synthesized in which the F atoms, usually bound to the boron center, have been replaced with 1-ethynylperylene units and a 4-pyridine residue is attached at the meso-position. The perylene units function as photon collectors over the wavelength range from 350 to 480 nm. Despite an unfavorable spectral overlap integral, rapid energy transfer takes place from the singlet-excited state of the perylene unit to the adjacent BODIPY residue, which is itself strongly fluorescent. The mean energy-transfer time is 7 ± 2 ps at room temperature. The dominant mechanism for the energy-transfer process is Dexter-type electron exchange, with Forster-type dipole–dipole interactions accounting for less than 10 % of the total transfer probability. There are no indications for light-induced electron transfer in this system, although there is evidence for a nonradiative decay channel not normally seen for F-type BODIPY Dyes. This new escape route is further exposed by the application of high pressure. The meso-pyridine group is a passive bystander until protons are added to the system. Then, protonation of the pyridine N atom leads to complete extinction of fluorescence from the BODIPY Dye and slight recovery of fluorescence from the perylene units. Quenching of BODIPY-based fluorescence is due to charge-transfer to the pyridinium unit whereas the re-appearance of perylene-based emission is caused by a reduction in the Forster overlap integral upon protonation. Other cations, most notably zinc(II) ions, bind to the pyridine N-atom and induce similar effects but the resultant conjugate is weakly fluorescent.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
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a molecular rotor based on an unhindered boron dipyrromethene BODIPY Dye
Chemistry of Materials, 2008Co-Authors: Mohammed A H Alamiry, Anthony Harriman, Andrew C Benniston, Graeme Copley, Kristopher J Elliott, Beverly Stewart, Yonggang ZhiAbstract:This work describes a fluorescent probe for following changes in the viscosity of the surrounding medium. The optical properties, fluorescence characteristics, and sensitivity to frictional forces with the surrounding medium are superior to the most commonly used molecular probe, namely dicyanovinyl julolidine. The photophysical properties of the target molecule have been recorded in a range of solvents under ambient conditions, over a wide temperature range, and as a function of applied pressure. The mechanism by which the probe responds to changes in local viscosity involves gyration of the meso-phenylene ring and accompanying distortion of the dipyrrin framework, as indicated by molecular dynamics simulations. Indeed, temperature-dependence measurements have established that the activation energy is small when the solvent viscosity is relatively low, but there is a turnover to strong activation control at very high viscosity. A small but definite solvent dependence appears when the viscosity is varied ...
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rapid energy transfer in cascade type BODIPY Dyes
Journal of the American Chemical Society, 2006Co-Authors: Anthony Harriman, Guillaume Izzet, Raymond ZiesselAbstract:Three new molecular dyads, comprising a bora-3a,4a-diaza-s-indacene (BODIPY) Dye linked to two aromatic polycycles via the boron center, have been synthesized and fully characterized. The polycyclic compounds are either pyrene or perylene, or a mixture of both. Whereas the absorption spectral profiles contain important contributions from each of the subunits, fluorescence occurs exclusively from the BODIPY fragment. Intramolecular excitation energy transfer is extremely efficient in each case, even though spectral overlap integrals for the pyrene-based system are modest. Although these polycycles are sterically congested, molecular dynamics simulations indicate that they are in dynamic motion, and this hinders proper computation of the orientation factors for Forster-type energy transfer. These new Dyes, especially the mixed polycycle system, greatly extend the range of excitation wavelengths that can be used for fluorescence microscopy.
Lopez F Arbeloa - One of the best experts on this subject based on the ideXlab platform.
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new laser Dye based on the 3 styryl analog of the BODIPY Dye pm567
Journal of Photochemistry and Photobiology A-chemistry, 2008Co-Authors: A Costela, I Garciamoreno, Mercedes Pintadosierra, F Amatguerri, Marta Liras, R Sastre, Lopez F Arbeloa, Banuelos J PrietoAbstract:Abstract We report the synthesis, photophysical properties and evaluation of laser Dye of a new BODIPY Dye with a 3-styryl substituent, PMS, and with the rest of the substituents as in the commercial Dye PM567. PMS shows an emission band at 584 nm in methanol, i.e. displaced ca. 50 nm to longer wavelengths with regard to the green-emission band of PM567, as well as a high-fluorescence quantum yield (0.82) and also a high-molar absorption coefficient (105 M−1 cm−1) in the same solvent. The laser action of the new Dye has been analyzed under transversal pumping at 532 nm, 5.5 mJ pulse−1 and up to 10 Hz repetition rate, in both liquid phase and incorporated into solid polymeric matrices of methyl methacrylate copolymerized with crosslinking or fluorinated monomers. Lasing emission at 602–610 nm, with maximum efficiencies of 18%, were reached in these media. In solid-fluorinated matrices, good lasing photostabilities were established, with 30% of the initial laser output remaining after 100,000 pump pulses at 10 Hz.
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structural changes in the BODIPY Dye pm567 enhancing the laser action in liquid and solid media
Advanced Functional Materials, 2007Co-Authors: I Garciamoreno, A Costela, F Amatguerri, Marta Liras, R Sastre, Lopez F Arbeloa, Banuelos J Prieto, Lourdes InfantesAbstract:In the search for more efficient and photostable solid-state Dye lasers, newly synthesized analogs of the borondipyrromethene (BODIPY) Dye PM567, bearing the polymerizable methacryloyloxypropyl group at position 2 (PMoMA) or at positions 2 and 6 (PDiMA), have been studied in the form of solid copolymers with methyl methacrylate (MMA). The parent Dye PM567, as well as the model analogs bearing the acetoxypropyl group in the same positions, PMoAc and PDiAc, respectively, have been also studied both in liquid solvents and in solid poly(MMA) (PMMA) solution. Although in liquid solution PMoAc and PDiAc have the same photophysical properties as PM567, PDiAc exhibited a photostability up to 10 times higher than that of PM567 in ethanol under 310 nm-irradiation. The possible stabilization factors of PDiAc have been analyzed and discussed on the basis of the redox potentials, the ability for singlet molecular oxygen [O2(1Δg)] generation, the reactivity with O2(1Δg), and quantum mechanical calculations. Both PMoAc and PDiAc, pumped transversally at 532 nm, lased in liquid solution with a high (up to 58 %), near solvent-independent efficiency. This enhanced photostabilization has been also observed in solid polymeric and copolymeric media. While the solid solution of the model Dye PDiAc in PMMA showed a lasing efficiency of 33 %, with a decrease in the laser output of ca. 50 % after 60 000 pump pulses (10 Hz repetition rate) in the same position of the sample, the solid copolymer with the double bonded chromophore, COP(PDiMA-MMA), showed lasing efficiencies of up to 37 %, and no sign of degradation in the laser output after 100 000 similar pump pulses. Even under the more demanding repetition rate of 30 Hz, the laser emission from this material remained at 67 % of its initial laser output after 400 000 pump pulses, which is the highest laser photostability achieved to date for solid-state lasers based on organic polymeric materials doped with laser Dyes. This result indicates that the double covalent linkage of the BODIPY chromophore to a PMMA polymeric matrix is even more efficient than the simple linkage, for its photostabilization under laser operation.
Peter S Conti - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of fluorescent pet probes based on 18f BODIPY Dye
Chemical Communications, 2014Co-Authors: Shuanglong Liu, Zhe Zhang, G Surya K Prakash, Peter S ContiAbstract:We report the direct conversion of fluorescent probes to PET/fluorescent probes after efficient [19F]/[18F] exchange at the BODIPY motif. The radiolabeling of a NIR BODIPY Dye was also established, which was conjugated with the RGD peptide for PET/fluorescence imaging of integrin expression in vivo.
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evaluation of 18f labeled BODIPY Dye as potential pet agents for myocardial perfusion imaging
Nuclear Medicine and Biology, 2014Co-Authors: Shuanglong Liu, Hong Shan, Francois P Gabbai, Peter S ContiAbstract:Abstract Introduction Despite the great potential of positron emission tomography/computed tomography (PET/CT) in cardiovascular disease imaging, one of the major limitations is the availability of PET probes with desirable half-lives and reasonable cost. In this report, we hypothesized that lipophilic cationic BODIPY Dye could be selectively accumulated in cardiac muscle, possibly for the development of novel PET myocardial perfusion imaging (MPI) probes. Methods A 18 F-labeled BODIPY Dye ([ 18 F] 1 ) was synthesized efficiently through a fluoride exchange reaction catalyzed by the Lewis acid tin chloride (SnCl 4 ). The compound was first evaluated by a cellular uptake assay in vitro , followed by biodistribution and microPET imaging studies in vivo . Results [ 18 F] 1 was obtained in more than 90% labeling yield, with >98% radiochemical purity. The HEK-293 cellular uptake assay showed that the preferential uptake of [ 18 F] 1 could be related to the cell membrane potential. The biodistribution data demonstrated high levels of [ 18 F] 1 accumulation in the heart. In the biodistribution study in mice, the radioactivity uptake in the heart, blood, liver and lung was 3.01±0.44, 0.39±0.09, 0.69±0.07, 1.71±0.27%ID/g, respectively, at 3h post-injection (p.i.). The heart-to-lung and heart-to-liver ratios are 1.76±0.14 and 4.37±0.51 at 3h p.i., respectively. Volume-of-interest analysis of the microPET images correlated well with the biodistribution studies in mice. The heart was clearly visualized in normal rats, with 0.72±0.18, 0.69±0.18, 0.67±0.20 and 0.59±0.17%ID/g uptake at 0.5, 1, 2 and 4h p.i., respectively. Conclusions 18 F-labeled BODIPY Dye showed good heart uptake and heart-to-blood and heart-to-lung contrast. A 18 F-labeled BODIPY Dyes may represent a new category of cationic PET agents for myocardial perfusion imaging.
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rapid aqueous 18f labeling of a BODIPY Dye for positron emission tomography fluorescence dual modality imaging
Chemical Communications, 2011Co-Authors: Zibo Li, Chiun Wei Huang, Todd W Hudnall, Franois P Gabbai, Peter S ContiAbstract:We report the rapid nucleophilic [18F]-radiolabeling of a BODIPY Dye in aqueous solutions. This radiolabeled Dye, whose biodistribution and clearance has been studied in mice, is stable in vivo and can be used as a positron emission tomography/fluorescence dual modality imaging agent.