Cation-induced pesticide binding and release by a functionalized calix[4]arene molecular host.

Ion-controlled switchable progress is very important in many biological behaviors. Here, we reported K(+)-controlled switch, this switch system exhibited excellent carbaryl (G) binding/release by fluorescent (FL), ultraviolet-visible (UV) spectrums and (1)H NMR spectroscopy. More importantly, the K(+)-controlled G binding/release switch based on C4C5 not only in the solution, but also on the surface, promising for the application for the pesticide controlled release.

A tryptophan responsive fluorescent and wettable dual-signal switch.

A new fluorescent dianthracene calix[4]arene (C4DA) was designed and synthesized via coupling the fluorescent anthracene units and calix[4]arene units. Then it was used to form self-assembled monolayers (C4DA-SAMs) by the simple click reaction to give the first fluorescent and wettable dual-signal switch for tryptophan (Trp) on a micro- and nano-structured silicon surface. The switch for Trp on the C4DA functional surface was confirmed by contact angle (CA) measurements and fluorescent spectroscopy (FL).

Hg2+ wettability and fluorescence dual-signal responsive switch based on a cysteine complex of piperidine-calix[4]arene.

The recognition of the mercury(II) ion (Hg(2+)) is essential because of its extreme toxicity in the environment and food. Hence we reported a novel cysteine (Cys) complex of piperidine-calix[4]arene (L) as a convenient and effective dual-signal responsive switch for Hg(2+). This switch system exhibited excellent selectivity toward Hg(2+) by fluorescence (FL), (1)H NMR spectroscopy and the atomic force microscopy (AFM).

Switchable wettability sensor for ion pairs based on calix[4]azacrown clicking.

A new calix[4]azacrown is synthesized from 1,3-dipropynyloxycalix[4]arene in a good yield of 85% and was modified on a silicon surface via click chemistry to be a switchable wettability sensor for ion pairs ([C(4)mim]Cl). A cooperative mechanism involving supramolecular interactions is proposed.