Flavanone-Based Fluorophores with Aggregation-Induced Emission Enhancement Characteristics for Mitochondria-Imaging and Zebrafish-Imaging.

Huaqiao Wang,Liyan Liu,Na Li,Depo Yang,Huiqing Luo,Feng He

doi:10.3390/molecules25143298

Abstract

Fluorophores with aggregation-induced emission enhancement (AIEE) characteristics applied in bioimaging have attracted more and more attention in recent years. In this work, a series of flavanone compounds with AIEE characteristics was developed and applied to fluorescence imaging of mitochondria and zebrafish. The compounds were readily prepared by the thermal dehydration of chalcone that was obtained by the reaction of o-hydroxyacetophenone and benzaldehyde. Two of these compounds showed significant AIEE characteristics by fluorescence performance experiments, including optical spectra, fluorescence spectra, fluorescence quantum yield (φF), fluorescence lifetime, and scanning electron microscopy (SEM). Compared with traditional organic fluorescent dyes, these compounds have high fluorescence emission and high fluorescence quantum yield in solid or aggregated state, which overcomes the shortcoming of aggregation-caused quenching (ACQ). More importantly, the two compounds exhibited low cytotoxicity and good cytocompatibility in A549 lung cells at the experimental concentration range and they specifically targeted mitochondria, which make it of great potential use in mitochondria labeling. In addition, they were embryonic membrane permeable and had different affinities for different tissues and organs of zebrafish, but mainly distributed in the digestive system, providing a basis for the application of such compounds in bioimaging. These AIEE compounds with superior properties could be of great potential use in mitochondria imaging and other in vivo studies.

Highlights

Organic fluorescent dyes have been widely used in bioimaging in recent years because of their excellent optical and biological properties, such as high fluorescence quantum yield, good biocompatibility and optical stability [1,2,3,4,5,6]
Traditional fluorescent dyes with aggregation-caused quenching (ACQ) characteristics emit strong fluorescence in monodisperse or dilute solutions, but emit weak fluorescence while molecules are aggregated at high concentrations or in solid state, so the application of these dyes is limited [7]
We found a series of flavonoid derivatives with aggregation-induced emission enhancement (AIEE) characteristics, which showed good cellular uptake and low cytotoxicity at the experimental concentrations range

Summary

Introduction

Organic fluorescent dyes have been widely used in bioimaging in recent years because of their excellent optical and biological properties, such as high fluorescence quantum yield, good biocompatibility and optical stability [1,2,3,4,5,6] It is very valued for biological application but traditional fluorescent dyes have an effect called aggregation-caused quenching (ACQ). Traditional fluorescent dyes with ACQ characteristics emit strong fluorescence in monodisperse or dilute solutions, but emit weak fluorescence while molecules are aggregated at high concentrations or in solid state, so the application of these dyes is limited [7]. Since the first report of AIEE molecules, these molecules have been widely studied and applied as chemical probes, bioprobes, and stimulus response probes, which provided a new way for organic luminescent materials to be applied in solid devices and high concentration conditions [17,18,19,20]

Methods

Results

Conclusion