Structurally-thrifty and visible-absorbing fluorophores

Xiao Luo; Yan Chen; Yanchun Li; Zhenglong Sun; Weihong Zhu; Xuhong Qian; Youjun Yang

doi:10.1016/j.saa.2020.118907

Structurally-thrifty and visible-absorbing fluorophores

Spectrochim Acta A Mol Biomol Spectrosc. 2021 Jan 15:245:118907. doi: 10.1016/j.saa.2020.118907. Epub 2020 Sep 4.

Authors

Xiao Luo¹, Yan Chen², Yanchun Li², Zhenglong Sun³, Weihong Zhu⁴, Xuhong Qian², Youjun Yang⁵

Affiliations

¹ State Key Laboratory of Bioreactor Engineering, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China; School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China.
² State Key Laboratory of Bioreactor Engineering, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China.
³ Suzhou Institute of Biomedical Engineering and Technology (SIBET), Chinese Academy of Sciences, Suzhou, Jiangsu 215163, China. Electronic address: sunzhl@sibet.ac.cn.
⁴ Key Laboratory for Advanced Materials, Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: weihongzhu@ecust.edu.cn.
⁵ State Key Laboratory of Bioreactor Engineering, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China. Electronic address: youjunyang@ecust.edu.cn.

PMID: 32932032
DOI: 10.1016/j.saa.2020.118907

Abstract

Fluorophores with a minimal push-pull backbone are actively pursued due to their potentials in biological labelling. Herein a series of structurally-thrifty and visible-absorbing fluorophores (SDXs) were successfully constructed following the D'D-π-A design strategy, in which a secondary donor (D') was introduced in conjugation with the donor (D) to enhance its electron donating capability. For a very small scaffold, SDXs exhibit a surprisingly long-wavelength absorption band in the visible spectral range (λ_abs = 420 nm) and a strong green fluorescence emission (λ_em = 530 nm) with a fluorescence quantum yield up to 0.84. Notably, fluorescence of SDXs was quenched in hydrogen-bonding solvents, e.g. MeOH and H₂O. This phenomenon renders SDXs feasibility for imaging of cellular non-hydrogen-bonding microenvironment, as demonstrated with BEAS-2B cells. These results proved that the D'D-π-A is a powerful design strategy to construct novel structurally-thrifty fluorophores.

Keywords: Cell imaging; D′D-π-A; Green emission; Structurally-thrifty; Visible-absorbing.