Recent advances in macrocyclic arenes-based fluorescent indicator displacement assays

Abstract

Macrocyclic arenes-based fluorescent indicator displacement assays (F-IDAs) offer a unique and innovative approach to chemosensing, taking molecular recognition in host-guest chemistry to a higher level. Because of their special architecture and versatile host–guest binding properties, macrocyclic arenes, principally calix[n]arenes and, in recent years, pillar[n]arenes, in combination with various fluorophores, are widely used in F-IDAs for the specific and selective sensing of cationic, anionic, and neutral analytes. In this paper, we review recent progress in the development of F-IDAs based on macrocyclic arenes and outline the prospects and remaining challenges relating to macrocyclic arenes-based F-IDAs.

A Water-Soluble Cycloparaphenylene: Synthesis and Application as a Supramolecular Receptor with Visible Fluorescence

“…The water-soluble corral [5]arene (Figure 1a, right) reported by Guo and Cai et al [8] showed high inclusion ability (~10 11 M -1 ), which arises from the induced fit process based on the structural change of the host molecule associated with the guest inclusion. The CPP-based water-soluble supramolecular host in this study has a rigid macrocyclic framework that allows for the inclusion of up to two cationic guest molecules into the cavity.…”

“…https://doi.org/10.26434/chemrxiv-2024-55822 ORCID: https://orcid.org/0000-0001-8860-0745 Content not peer-reviewed by ChemRxiv. License: CC BY-NC-ND 4.0 [6]arene (left) [4] and watersoluble corral [5]arene (right), [8] (b) [8] cycloparaphenylene derivative with two alkoxysulphonate units. [12] (c) Water-soluble [9]cycloparaphenylene derivative containing three hydrindacene units with four carboxylates at the 2,6-positions (This work).…”

“…On the other hand, the supramolecular hosts exhibiting visible fluorescence in water typically involve either the immobilization of a fluorophore or inclusion of a fluorescent guest into the macrocyclic structures. [5] A limited number of water-soluble macrocyclic hosts exhibit visible fluorescence directly from their cyclic skeleton, with examples including macrocyclic hosts containing anthracene and pyrene. [6] [7] Very recently, Guo and Cai et al reported that water solubilization of a macrocyclic π-conjugated compound consisting of five diphenylacetylene units linked at the 2,2'-position (corral [5]arene) by introducing sulfate groups at the 4,4'-positions of each units, which selectively forms 1:1 inclusion complexes with various cationic guest molecules in water with extremely high association constants (Ka ~ 10 11 M -1 ) (Figure 1a, right).…”

“…[5] A limited number of water-soluble macrocyclic hosts exhibit visible fluorescence directly from their cyclic skeleton, with examples including macrocyclic hosts containing anthracene and pyrene. [6] [7] Very recently, Guo and Cai et al reported that water solubilization of a macrocyclic π-conjugated compound consisting of five diphenylacetylene units linked at the 2,2'-position (corral [5]arene) by introducing sulfate groups at the 4,4'-positions of each units, which selectively forms 1:1 inclusion complexes with various cationic guest molecules in water with extremely high association constants (Ka ~ 10 11 M -1 ) (Figure 1a, right). [8] However, water-soluble supramolecular hosts composed of aromatic rings connected though the methylene or ethynylene units would suffer from reduced fluorescence properties, especially brightness (ε×ΦF) based on fluorescence quantum yield (ΦF), due to the thermal vibration arising from the molecular flexibility and aggregation [4] induced by the intermolecular dispersion interactions in the aqueous environment.…”

Editorial: Host–guest chemistry of macrocycles— Volume II

“…In a minireview paper, Duan et al further summarized recent progresses on FID assays based on macrocyclic arenes ( Duan et al, 2022b ). The authors mainly divided the content to two parts: CA[n]-based FID assays and PA[n]-based FID assays.…”