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Abstract The first near IR fluorescent probe for the chemoselective and enantioselective recognition of arginine in aqueous solution is reported in this work. This probe, made of a 1,1’‐binaphthyl‐based chiral aldehyde unit and a rhodamine‐based near IR chromophore, in combination with La3+exhibits highly chemoselective as well as enantioselective fluorescent enhancement with arginine at λ=764 nm upon excitation at λ=690 nm. Little or no fluorescent response is observed toward the chirality miss‐matched arginine enantiomer or other common amino acids and their enantiomers. This probe also allows visual discrimination of the arginine enantiomers because of its fast and distinct color change upon interaction with the substrate.
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Chiral Metallopolymers for Redox‐Mediated Enantioselective Interactions
Abstract Synthetic chiral platforms can be a powerful platform for enantioselective interactions, especially when coupled with redox‐mediated electrochemical processes. While metallopolymers are versatile platforms for molecularly selective binding, their application for chiral applications is limited. In particular, the recognition and separation of biologically relevant chiral molecules can be key for biomanufacturing and diagnostics. Here, the design of chiral redox‐polymers enables electrochemically‐controlled enantioselective interactions, and supramolecular chirality is leveraged for enhancing recognition towards target enantiomers. Chiral redox‐metallopolymers are synthesized based on Ugi's amine‐inspired chiral monomers, and their enantioselective recognition toward ionic enantiomers such as tryptophan and naproxen is demonstrated, with higher enanhcement provided by the chiral redox‐polymer over the single‐site, chiral building bloack itelf. 2D nuclear magnetic resonance spectroscopy and solid‐state circular dichroism support the emergence of supramolecular chirality resulting from the intramolecular interaction between the ferrocene and the alkyl group in the backbone. The half potential shift of the redox‐polymers behaves linearly from 0% to 100%eel‐tryptophan to enable enantiomer quantification. Investigation on solvent polarity and pH effect reveal that the enantioselective mechanism is attributed to the subtle balance between hydrogen bonding and π–π interaction. This study highlights the potential of chiral redox‐metallopolymers as platforms for electrochemically‐modulated enantioselective interactions towards a range of amino acids and pharmaceutical carboxylates.
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- PAR ID:
- 10419022
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 33
- Issue:
- 27
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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