Pressure-induced excimer formation and fluorescence enhancement of an anthracene derivative

Controlled light-mediated delivery of biological analytes enables the investigation of highly reactivity molecules within cellular systems. As many biological effects are concentration dependent, it is critical to determine the location, time, and quantity of analyte donation. In this work, we have developed the first photoactivatable donor for formaldehyde (FA). Our optimized photoactivatable donor, photoFAD-3, is equipped with a fluorescence readout that enables monitoring of FA release with a concomitant 139-fold fluorescence enhancement. Tuning of photostability and cellular retention enabled quantification of intracellular FA release through cell lysate calibration. Application of photoFAD-3 uncovered the concentration range necessary for arresting wound healing in live cells. This marks the first report where a photoactivatable donor for any analyte has been used to quantify intracellular release.

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Double Ring-Closing Approach for the Synthesis of 2,3,6,7-Substituted Anthracene Derivatives

10.26434/chemrxiv.12052647.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Birgit Meindl ◽

Katharina Pfennigbauer ◽

Berthold Stöger ◽

Martin Heeney ◽

Florian Glöcklhofer

Keyword(s):

Wittig Reaction ◽

Condensation Reaction ◽

Synthetic Methods ◽

Anthracene Derivative ◽

Double Ring ◽

Mild Conditions ◽

Wide Range ◽

Anthracene Derivatives

Anthracene derivatives have been used for a wide range of applications and many different synthetic methods for their preparation have been developed. However, despite continued synthetic efforts, introducing substituents in some positions has remained difficult. Here we present a method for the synthesis of 2,3,6,7-substituted anthracene derivatives, one of the most challenging anthracene substitution patterns to obtain. The method is exemplified by the preparation of 2,3,6,7-anthracenetetracarbonitrile and employs a newly developed, stable protected 1,2,4,5-benzenetetracarbaldehyde as the precursor. The precursor can be obtained in two scalable synthetic steps from 2,5-dibromoterephthalaldehyde and is converted into the anthracene derivative by a double intermolecular Wittig reaction under very mild conditions followed by a deprotection and intramolecular double ring-closing condensation reaction. Further modification of the precursor is expected to enable the introduction of additional substituents in other positions and may even enable the synthesis of fully substituted anthracene derivatives by the presented approach.<br>

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Faculty Opinions recommendation of Fluorescence enhancement at docking sites of DNA-directed self-assembled nanoantennas.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717982902.793472097 ◽

2013 ◽

Author(s):

Ben Schuler ◽

Hagen Hofmann

Keyword(s):

Fluorescence Enhancement ◽

Docking Sites ◽

Self Assembled

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The Difference in Sensing Properties Towards Anions between Two Pyridinium Amide-Based Receptors with a Subtle Change of H-Bond Position

Letters in Organic Chemistry ◽

10.2174/1570180816666190801100603 ◽

2020 ◽

Vol 17 (6) ◽

pp. 472-478

Author(s):

Wei-tao Gong ◽

Wei-dong Qu ◽

Guiling Ning

Keyword(s):

Fluorescence Enhancement ◽

Small Difference ◽

Fluorescence Emission ◽

Subtle Change ◽

Sensing Properties ◽

Naked Eye ◽

Recognition Ability ◽

The Difference ◽

L1 And L2

Two pyridinium amide-based receptors L1 and L2 with a small difference of H-bond position of the amide have been synthesized and characterized. Interestingly, they exhibited a huge difference in sensing towards AcO- and H2PO4 -, respectively. Receptor L1 was found to be ‘naked-eye’ selective for AcO- anions, while receptor L2 showed clear fluorescence enhancement selective to H2PO4 - anion. The recognition ability has been established by fluorescence emission, UV-vis spectra, and 1HNMR titration.

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Semiautomated microfluorometric instrument and reagent system for monitoring disease-related immunosuppression.

Clinical Chemistry ◽

10.1093/clinchem/28.9.1887 ◽

1982 ◽

Vol 28 (9) ◽

pp. 1887-1893 ◽

Cited By ~ 1

Author(s):

D F Ranney ◽

A J Quattrone

Keyword(s):

Immune Response ◽

Dna Content ◽

Peripheral Blood ◽

Fluorescence Enhancement ◽

Photon Counting ◽

Peripheral Blood Lymphocytes ◽

Response Modulation ◽

Blood Lymphocytes ◽

Complex Test ◽

Immune Response Modulation

Abstract Several common metabolites and drugs in the serum in of patients with inflammatory, infectious, autoimmune, immunodeficient, neoplastic, and toxicant-induced diseases can produce artifactual suppression of the [methyl-3H]-thymidine assay, which is widely used to evaluate lymphocyte responsiveness. We have developed a sensitive, semiautomated, fluorescence-enhancement assay in which true immunosuppressors are measured in the presence of absence of such interfering substances. Peripheral blood lymphocytes are activated with mitogens in standard microtiter culture trays. Changes in lymphocyte DNA content are quantified with a reagent formulation containing mithramycin, the fluorescence of which is enhanced on binding to DNA in the presence of MgCl2. We solubilize cells within the intact microtiter tray by using an automated, inverted "Array Sonicator," and measure fluorescence with an automated, photon-counting fluorometer. With this system, immune response modulation can be accurately assessed in the presence of patients' sera and other complex test substances (e.g., supernates from hybridomas, fermentation vats, viral preparations, and macrophage cultures.

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