Polyglycerol‐Dendronized Perylenediimides as Stable, Water‐Soluble Fluorophores

Abstract

The synthesis and photophysical properties of water-soluble, fluorescent polyglycerol-dendronized perylenediimides 1–4 are reported. The polyglycerol dendrons, which are known to be highly biocompatible, are found to confer high water-solubility on the perylenediimide in aqueous media while retaining its excellent fluorescent properties. Furthermore, intramolecular cross-linking of the polyglycerol dendrons using the ring-closing metathesis reaction not only enhances the photostability but also reduces the size of perylenediimide-cored dendrimers. The permeability of the various dendritic shells is probed using heavy metal ion quenchers and compared to non-dendritic but water-soluble perylenediimide 5.

Fluorescence Products from Terrylenediimide with Singlet Oxygen: Red, Green, and Near-Infrared Emission

“…The appropriate wavelength for exciting the NIR fluorescence can be chosen based on the calculated maximum absorption (Table S1), which is 710 and 902 nm for P4 and P5 respectively. It should be noted that although NIR fluorescent TDI oxidation product may be beneficial for in vivo observation, TDI itself is water-insoluble and cannot be directly applied to biological system, but promising strategies have been developed to improve solubility of such type of rylene dyes …”

Intramolecularly Cross-Linked Polymers: From Structure to Function with Applications as Artificial Antibodies and Artificial Enzymes

“…In collaboration with Rainer Haag, we extended this chemistry to polyglycerol dendrimers and hyperbranched polymers. − The former are an ideal choice for RCM cross-linking because in their iterative synthesis each generation proceeds through an intermediate with allyl ether end groups. The cross-linked polyglycerol shell was shown to surround a perylenediimide fluorophore and could be made water-soluble by dihydroxylation . Finally, we also showed that four- and eight-armed star polymers with porphyrin cores and alkene-containing polystyrene arms could undergo RCM cross-linking …”

“…The cross-linked polyglycerol shell was shown to surround a perylenediimide fluorophore and could be made water-soluble by dihydroxylation. 38 Finally, we also showed that four-and eight-armed star polymers with porphyrin cores and alkene-containing polystyrene arms could undergo RCM cross-linking. 39…”

Highly Photostable and Fluorescent Microporous Solids Prepared via Solid-State Entrapment of Boron Dipyrromethene Dyes in a Nascent Metal–Organic Framework

“…The enhanced photostability of PM605 within ZIF-8 may be due to partial shielding of the dye excited state by the framework, with reduced molecular mobility and hindered encounters with solvent and/or O 2 molecules minimizing the rates of photochemical (e.g., rearrangements) and photophysical (e.g., sensitization of singlet oxygen followed by chromophore oxidation) processes related to dye photobleaching . Similar mechanisms have been suggested for dyes complexed to supramolecular hosts , or linked to dendrimers. − …”