TY - JOUR A1 - Mueller, Stefan A1 - Lüttig, Julian A1 - Malý, Pavel A1 - Ji, Lei A1 - Han, Jie A1 - Moos, Michael A1 - Marder, Todd B. A1 - Bunz, Uwe H. F. A1 - Dreuw, Andreas A1 - Lambert, Christoph A1 - Brixner, Tobias T1 - Rapid multiple-quantum three-dimensional fluorescence spectroscopy disentangles quantum pathways JF - Nature Communications N2 - Coherent two-dimensional spectroscopy is a powerful tool for probing ultrafast quantum dynamics in complex systems. Several variants offer different types of information but typically require distinct beam geometries. Here we introduce population-based three-dimensional (3D) electronic spectroscopy and demonstrate the extraction of all fourth- and multiple sixth-order nonlinear signal contributions by employing 125-fold (1⨯5⨯5⨯5) phase cycling of a four-pulse sequence. Utilizing fluorescence detection and shot-to-shot pulse shaping in single-beam geometry, we obtain various 3D spectra of the dianion of TIPS-tetraazapentacene, a fluorophore with limited stability at ambient conditions. From this, we recover previously unknown characteristics of its electronic two-photon state. Rephasing and nonrephasing sixth-order contributions are measured without additional phasing that hampered previous attempts using noncollinear geometries. We systematically resolve all nonlinear signals from the same dataset that can be acquired in 8 min. The approach is generalizable to other incoherent observables such as external photoelectrons, photocurrents, or photoions. KW - Atomic and molecular interactions with photons KW - Optical spectroscopy Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202529 VL - 10 ER - TY - JOUR A1 - Merz, Julia A1 - Dietrich, Lena A1 - Nitsch, Jörn A1 - Krummenacher, Ivo A1 - Braunschweig, Holger A1 - Moos, Michael A1 - Mims, David A1 - Lambert, Christoph A1 - Marder, Todd B. T1 - Synthesis, Photophysical and Electronic Properties of Mono‐, Di‐, and Tri‐Amino‐Substituted Ortho‐Perylenes, and Comparison to the Tetra‐Substituted Derivative JF - Chemistry – A European Journal N2 - We synthesized a series of new mono‐, di‐, tri‐ and tetra‐substituted perylene derivatives with strong bis(para‐methoxyphenyl)amine (DPA) donors at the uncommon 2,5,8,11‐positions. The properties of our new donor‐substituted perylenes were studied in detail to establish a structure‐property relationship. Interesting trends and unusual properties are observed for this series of new perylene derivatives, such as a decreasing charge transfer (CT) character with increasing number of DPA moieties and individual reversible oxidations for each DPA moiety. Thus, (DPA)‐Per possesses one reversible oxidation while (DPA)\(_{4}\)‐Per has four. The mono‐ and di‐substituted derivatives display unusually large Stokes shifts not previously reported for perylenes. Furthermore, transient absorption measurements of the new derivatives reveal an excited state with lifetimes of several hundred microseconds, which sensitizes singlet oxygen with quantum yields of up to 0.83. KW - borylation KW - intersystem crossing KW - luminescence KW - polycyclic aromatic hydrocarbon KW - triarylamine Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-217835 VL - 26 IS - 52 SP - 12050 EP - 12059 ER - TY - JOUR A1 - Kole, Goutam Kumar A1 - Košćak, Marta A1 - Amar, Anissa A1 - Majhen, Dragomira A1 - Božinović, Ksenija A1 - Brkljaca, Zlatko A1 - Ferger, Matthias A1 - Michail, Evripidis A1 - Lorenzen, Sabine A1 - Friedrich, Alexandra A1 - Krummenacher, Ivo A1 - Moos, Michael A1 - Braunschweig, Holger A1 - Boucekkine, Abdou A1 - Lambert, Christoph A1 - Halet, Jean‐François A1 - Piantanida, Ivo A1 - Müller‐Buschbaum, Klaus A1 - Marder, Todd B. T1 - Methyl Viologens of Bis‐(4’‐Pyridylethynyl)Arenes – Structures, Photophysical and Electrochemical Studies, and their Potential Application in Biology JF - Chemistry – A European Journal N2 - A series of bis‐(4’‐pyridylethynyl)arenes (arene=benzene, tetrafluorobenzene, and anthracene) were synthesized and their bis‐N‐methylpyridinium compounds were investigated as a class of π‐extended methyl viologens. Their structures were determined by single crystal X‐ray diffraction, and their photophysical and electrochemical properties (cyclic voltammetry), as well as their interactions with DNA/RNA were investigated. The dications showed bathochromic shifts in emission compared to the neutral compounds. The neutral compounds showed very small Stokes shifts, which are a little larger for the dications. All of the compounds showed very short fluorescence lifetimes (<4 ns). The neutral compound with an anthracene core has a quantum yield of almost unity. With stronger acceptors, the analogous bis‐N‐methylpyridinium compound showed a larger two‐photon absorption cross‐section than its neutral precursor. All of the dicationic compounds interact with DNA/RNA; while the compounds with benzene and tetrafluorobenzene cores bind in the grooves, the one with an anthracene core intercalates as a consequence of its large, condensed aromatic linker moiety, and it aggregates within the polynucleotide when in excess over DNA/RNA. Moreover, all cationic compounds showed highly specific CD spectra upon binding to ds‐DNA/RNA, attributed to the rare case of forcing the planar, achiral molecule into a chiral rotamer, and negligible toxicity toward human cell lines at ≤10 μM concentrations. The anthracene‐analogue exhibited intracellular accumulation within lysosomes, preventing its interaction with cellular DNA/RNA. However, cytotoxicity was evident at 1 μM concentration upon exposure to light, due to singlet oxygen generation within cells. These multi‐faceted features, in combination with its two‐photon absorption properties, suggest it to be a promising lead compound for development of novel light‐activated theranostic agents. KW - cell imaging KW - DNA/RNA binding KW - methyl viologen KW - singlet oxygen KW - two-photon absorption Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-287126 VL - 28 IS - 40 ER - TY - JOUR A1 - Griesbeck, Stefanie A1 - Michail, Evripidis A1 - Rauch, Florian A1 - Ogasawara, Hiroaki A1 - Wang, Chenguang A1 - Sato, Yoshikatsu A1 - Edkins, Robert M. A1 - Zhang, Zuolun A1 - Taki, Masayasu A1 - Lambert, Christoph A1 - Yamaguchi, Shigehiro A1 - Marder, Todd B. T1 - The Effect of Branching on the One‐ and Two‐Photon Absorption, Cell Viability, and Localization of Cationic Triarylborane Chromophores with Dipolar versus Octupolar Charge Distributions for Cellular Imaging JF - Chemistry – A European Journal N2 - Two different chromophores, namely a dipolar and an octupolar system, were prepared and their linear and nonlinear optical properties as well as their bioimaging capabilities were compared. Both contain triphenylamine as the donor and a triarylborane as the acceptor, the latter modified with cationic trimethylammonio groups to provide solubility in aqueous media. The octupolar system exhibits a much higher two‐photon brightness, and also better cell viability and enhanced selectivity for lysosomes compared with the dipolar chromophore. Furthermore, both dyes were applied in two‐photon excited fluorescence (TPEF) live‐cell imaging. KW - boranes KW - cell imaging KW - fluorescence KW - lysosome KW - two-photon excited fluorescence Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-212887 VL - 25 IS - 57 SP - 13164 EP - 13175 ER - TY - JOUR A1 - Ferger, Matthias A1 - Roger, Chantal A1 - Köster, Eva A1 - Rauch, Florian A1 - Lorenzen, Sabine A1 - Krummenacher, Ivo A1 - Friedrich, Alexandra A1 - Košćak, Marta A1 - Nestić, Davor A1 - Braunschweig, Holger A1 - Lambert, Christoph A1 - Piantanida, Ivo A1 - Marder, Todd B. T1 - Electron‐Rich EDOT Linkers in Tetracationic bis‐Triarylborane Chromophores: Influence on Water Stability, Biomacromolecule Sensing, and Photoinduced Cytotoxicity JF - Chemistry – A European Journal N2 - Three novel tetracationic bis‐triarylboranes with 3,4‐ethylenedioxythiophene (EDOT) linkers, and their neutral precursors, showed significant red‐shifted absorption and emission compared to their thiophene‐containing analogues, with one of the EDOT‐derivatives emitting in the NIR region. Only the EDOT‐linked trixylylborane tetracation was stable in aqueous solution, indicating that direct attachment of a thiophene or even 3‐methylthiophene to the boron atom is insufficient to provide hydrolytic stability in aqueous solution. Further comparative analysis of the EDOT‐linked trixylylborane tetracation and its bis‐thiophene analogue revealed efficient photo‐induced singlet oxygen production, with the consequent biological implications. Thus, both analogues bind strongly to ds‐DNA and BSA, very efficiently enter living human cells, accumulate in several different cytoplasmic organelles with no toxic effect but, under intense visible light irradiation, they exhibit almost instantaneous and very strong cytotoxic effects, presumably attributed to singlet oxygen production. Thus, both compounds are intriguing theranostic agents, whose intracellular and probably intra‐tissue location can be monitored by strong fluorescence, allowing switching on of the strong bioactivity by well‐focused visible light. KW - boranes KW - DNA/RNA sensors KW - fluorescent probes KW - singlet oxygen KW - theranostics Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-287241 VL - 28 IS - 48 ER -