Novel coumarin-based ratiometric bifunctional fluorescent probe mimicking a set-reset memorized device

A novel coumarin-based fluorescent sensor CHE, incorporating 2-hydrazinylbenzothiazole and coumarin aldehyde, has been developed that demonstrated a preferential detection of Hg2+ and Ag+ in presence of interferences. Compared to previously prevalent intensity-based fluorescent probes, CHE exhibited a ratiometric fluorescence response to Hg2+ and Ag+, and further accurately differentiated Hg2+ and Ag + using the differential extractive ability of EDTA when interacting with ion-CHE complexes. Sensing mechanism was investigated and elucidated. The chemosensor CHE was successfully applied to detect Hg2+ and Ag+ in six distinct samples with satisfactory results. Additionally, combinatorial logic circuits were constructed utilizing three distinct logic gates (NOT, OR, and INH) based on the sensor's differential output signals in response to Hg2+/Ag+ and other cations. Interestingly, utilizing the reversible and reproducible switching behavior of the EDTA interaction with Hg2+, a conceptual 'Write-Read-Erase-Read' memory function with multi-write capability was proposed, offering a novel perspective for molecular-based memory systems.

A simple urea-based multianalyte and multichannel chemosensor for the selective detection of F−, Hg2+ and Cu2+ in solution and cells and the extraction of Hg2+ and Cu2+ from real water sources: a logic gate mimic ensemble

Herein, a hydrazine-based chromogenic, fluorogenic and electrochemical chemosensor BCC [1,5-bis(4-cyanophenyl) carbonohydrazide] was reported.

Nanomolar-level selective dual channel sensing of Cu2+and CN−from an aqueous medium by an opto-electronic chemoreceptor

A novel chromogenic and fluorogenic chemoreceptor exhibiting a proclivity towards Cu²⁺and CN⁻, with applications in bioimaging and molecular electronics, was developed.

Sequential Detection of CN- and HSO4- Anions in an Aqueous Environment Utilizing a New Colorimetric Azoimine Receptor: Mimicking Logic Gate Behaviour and a Security Keypad Lock

A new isonicotiamide-based azoimine receptor has been successfully devised and synthesised for dual-recognition of CN− and HSO4− anions in aqueous media (3 : 2 DMSO–water solution). The devised azomethine probe detected lethal cyanide ions under UV-vis spectroscopy through the rapid appearance of an orange colour. More importantly, the colour and spectroscopic changes of the devised chemosensor could be revived upon the addition of HSO4− to the sensor containing cyanide ions. Furthermore, other surveyed anions failed to induce a similar response. Interestingly, based on changes in absorption intensity at a particular wavelength in the presence of two aforementioned anions, as two chemical inputs, an INHIBIT logic gate has been elaborated. Moreover, the reversibility of the sensory system provided an opportunity to present a sequential logic circuit at a molecular level. In accession, the target chemosensor could operate as a molecular keypad lock with sequential chemical inputs of CN− and HSO4− anions.

Colorimetric and fluorimetric response of Schiff base molecules towards fluoride anion, solution test kit fabrication, logical interpretations and DFT-D3 study

Two newly synthesized Schiff base molecules are herein reported as anion sensors.