Theoretical Design of Near-Infrared Fluorescent Sensorfor F Anion Detection Based on 10-Hydroxybenzo[ h ]quinolineBackbone

Proper design and development of near-infrared (NIR) fluorescent sensors is very important for applications in vivo. In this work, we theoretically designed a ratiometric and NIR fluorescent sensor based on the 10-hydroxybenzo[h]quinoline (HBQ) backbone via systematically investigating the substituent effects of electron-donating groups (−NH2, −CH3, −C(CH3)3) and electron-withdrawing groups (−NO2, −CN, −F, −Cl, −CF3) at the proton donor site on the proton transfer process in HBQ in both the S0 and the S1 states. According to the calculated potential energy profiles along the proton transfer as well as the photophysical properties among all the derivatives, we successfully screened out that 7NH2-HBQ is a promising fluorescent sensor exhibiting the near IR emission spectra accompanied by the large Stokes shift. The potential use of 7NH2-HBQ for F– detection among anions (F–, Cl–, and Br–) was further studied, and the results showed that 7NH2-HBQ is very sensitive and selective toward F– based on the intermo...