Design of large Stokes shift fluorescent ortho-bis-styrylbenzenes. Optical characterization and fluoride sensing in logical gates

• Published in: Dyes and pigments 2024-06, Vol.225, p.112035, Article 112035
• Main Authors: Lera-Garrido, Fernando J.de, Vázquez-Villar, Víctor, Fernández-Liencres, M. Paz, Sánchez-Ruiz, Antonio, Navarro, Amparo, Tolosa, Juan, García-Martínez, Joaquín C.
• Format: Article
• Language: English
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2024.112035

This study combines underexplored fluorescent structures with large Stokes shifts, such as ortho-derivatives of bis(styryl)benzenes, for detecting three anions (fluoride, cyanide, and hydroxyl) through the implementation of fluorescent molecular logic gates. Importantly, this approach allows for the detection of multiple analytes and discrimination between analytes with closely similar behaviours, reducing the need for sample pre-treatments and enhancing efficiency in complex environmental analyses. Compounds with large Stokes shifts are essential in spectroscopy, offering reduced self-absorption, improved sensitivity, minimal spectral overlap, better resolution, and interference-free use of multiple fluorescent compounds. Therefore, we present a study on how the substitution of these oBSB compounds influences their optical properties. Through Time-Dependent Density Functional Theory (TD-DFT) calculations, we gain comprehensive insights into the molecular structure and photophysical properties, elucidating the exceptional Stokes shift exhibited by these compounds. Additionally, our findings offer a deeper understanding of the electronic states and changes in molecular geometry that contribute to their unique optical behaviour. Finally, the appropriate analysis of the fluorescent responses of these compounds as inputs in logic gates allows the detection of fluoride, cyanide, or hydroxyl anions in an unknown sample. •The study introduced four novel o-bis(styryl)benzene (oBSB) compounds, each with distinct decoration motifs, showcasing varied responses to fluoride, cyanide, and hydroxyl anions. These compounds exhibit notable characteristics, such as moderate to high quantum yields and large Stokes shifts, making them highly promising for sensor applications.•The large Stokes shift observed in these compounds arises from the involvement of both excited states, S1 and S2, in the absorption-emission process. This feature makes oBSBs unique and further reinforces their suitability for sensor applications.•The distinct sensitivity of these compounds to fluoride, cyanide, and hydroxyl anions has enabled the design of fluorescent logic gates, facilitating the identification of specific anions in unknown samples. Compounds 1 and 4 demonstrated exceptional potential for quantifying fluoride levels in a sample.•The successful development of these fluorescent molecular logic gates and their superior performance in anion detection offer promising prospects for advancing