Ters, CSIR-HRDC Campus Sector 19, Kamala Nehru Nagar, Ghaziabad 201002, India Correspondence: [email protected]; Tel.: +61-3-9925-Citation: Jakku, R.K.; Mirzadeh, N.; Priv , S.H.; Reddy, G.; Vardhaman, A.K.; Lingamallu, G.; Trivedi, R.; bhargava, S.K. TetraphenylethyleneSubstituted Bis(thienyl)imidazole (DTITPE), An Effective Molecular Sensor for the Detection and Quantification of Fluoride Ions. Chemosensors 2021, 9, 285. https:// doi.org/10.3390/chemosensors9100285 Academic Editors: Valerio Vignoli and Enza PanzardiAbstract: Fluoride ion plays a pivotal part within a range of biological and chemical applications even so excessive exposure can cause severe kidney and gastric challenges. A very simple and selective molecular sensor, 4,5-di(thien-2-yl)-2-(4-(1,two,2-triphenylvinyl)-phenyl)-1H-imidazole, DTITPE, has been synthesized for the detection of fluoride ions, with detection limits of 1.37 10- 7 M and two.67 10-13 M, determined by UV-vis. and fluorescence spectroscopy, respectively. The variation in the optical properties of the molecular sensor inside the presence of fluoride ions was explained by an intermolecular charge transfer (ICT) process among the bis(thienyl) and tetraphenylethylene (TPE) moieties upon the formation of a N-H–F- hydrogen bond on the imidazole proton. The sensing mechanism exhibited by DTITPE for fluoride ions was confirmed by 1 H NMR spectroscopic studies and density functional theory (DFT) calculations. Test strips coated with the molecular sensor can detect fluoride ions in THF, undergoing a color transform from white to yellow, which could be observed together with the naked eye, showcasing their possible SCH-23390 manufacturer real-world application. Search phrases: bis(thienyl) imidazole; tetraphenylethylene; molecular sensor; fluoride anion; fluorescenceReceived: 23 July 2021 Accepted: 28 September 2021 Published: 6 OctoberPublisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.1. Introduction The detection and recognition of anionic analytes has created into an exceptionally active investigation field in recent years [14]. Anions play a important role in a range of biological and chemical processes, and their detection, even at incredibly low concentrations, has been the motivation for continuous improvement in sensor development over the final few decades [15,16]. Based on the prior literature, the probable toxic dose (PTD) of fluoride was defined at 5 mg/kg of physique mass. The PTD could be the minimal dose that could trigger severe and life-threatening signs and symptoms which require immediate therapy and hospitalization [17]. The fluoride anion, possessing the smallest ionic radii, tough Lewis basic nature and higher charge density, has emerged as an appealing topic for sensor design resulting from its association using a wide range of organic, medicinal, and technological procedures. Furthermore, fluoride ions play a important part in dental health [18] and has been utilized for the remedy of osteoporosis [191] and for military uses, like the refinement of Infigratinib References uranium for nuclear weapons [22]. It really is readily absorbed by the human bodyCopyright: 2021 by the authors. Licensee MDPI, Basel, Switzerland. This short article is definitely an open access write-up distributed under the terms and situations from the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ four.0/).Chemosensors 2021, 9, 285. https://doi.org/10.3390/chemosensorshttps://www.mdpi.com/journal/chemosensorsChemosensors 20.