Apparent fractal distribution of open durations in cyclodextrin-based ion channels

Abstract

Cyclodextrin-based ion channels are readily prepared via a "click" reaction and exhibit a range of membrane activities consistent with the formation of ion channels in planar bilayer membranes. The durations of irregular and transient conductance events appear to follow a power-law scaling.

Palladium(II)‐Mediated Assembly of Biotinylated Ion Channels

“…[12] In a similar manner, active half-channel ionophores have been created by linking multiple steroids to calixarenes, [13] spermine [14] or b-cyclodextrin. [15] Our aim was to elaborate 1 into ion channels able to undergo additional levels of supramolecular assembly, where an external multivalent ligand will laterally assemble membrane-spanning Pd II complexes into pores. Biotinylation in particular, for example to give 2 (Scheme 1), will also allow these channels to be linked through a multivalent avidin bridge to the commercially available suite of biotinylated proteins and enzymes.…”

When Cyclodextrins Meet Click Chemistry

“…In a totally different field of application, Chui and Fyles developed CD‐based ion channels by using a click reaction (Scheme ) 32. These compounds exhibited a range of membrane activities consistent with the formation of ion channels in planar bilayer membranes.…”

A Chiral and Colorful Redox Switch: Enhanced π Acidity in Action

“…Herein, we introduce simple sulfur redox chemistry [1,2] to generate enhanced p acidity, [3][4][5] demonstrate the functional relevance of the investigated system through anion transport experiments, [2,[4][5][6][7] and create the switchable chiral p-acidic surfaces that are needed for future applications toward asymmetric anion-p catalysis. Efforts to expand the number of noncovalent interactions available to construct new supramolecular systems with significant functions such as sensors, optoelectronic devices, and catalysts or drugs are of paramount importance.…”

“…Efforts to expand the number of noncovalent interactions available to construct new supramolecular systems with significant functions such as sensors, optoelectronic devices, and catalysts or drugs are of paramount importance. [4] To contribute to this adventure, we have explored the use of potential-macrodipole, [2,7] anionmacrodipole, [7] aromatic electron donor-acceptor [7] as well as anion-p interactions [4,5] to build stimuli-responsive transport systems [4][5][6][7] in lipid bilayer membranes. Core-substituted naphthalenediimides (cNDIs) [8] are ideal to explore the usefulness of anion-p interactions to create functional systems because the quadrupole moment of the parent NDI 1 is already Q ZZ = + 19 B (Figure 1 a and b).…”

“…[5][6][7][8] In a recent inversion of paradigm, activity to transport anions was considered as a tool to identify more exotic interactions and to assess their functional relevance for translocation and catalysis, where much weaker interactions are of interest than for simple binding. [4,14] For this purpose, the ability of cNDIs 2-6 to use anion-p interactions to transport anions across lipid bilayer membranes was evaluated with the 8-hydroxy-1,3,6-pyrenetrisulfonate (HPTS) assay.…”