Multiple organelle-targeted 1,8-naphthyridine derivatives for detecting the polarity of organelles.
Hao-Chi HaoGang ZhangRu SunYu-Jie XuJian-Feng GePublished in: Journal of materials chemistry. B (2023)
Four 1,8-naphthyridine derivatives (1a-1d) with different organelle targeting abilities were obtained using the Knoevenagel condensation reaction of 1,8-naphthyridine with 4-( N , N -diethylamino)benzaldehyde (2a), 4-( N , N -diphenylamino)benzaldehyde (2b), 4-(piperazin-1-yl)benzaldehyde (2c) and 4-(ethyl(4-formylphenyl)amino)- N -(2-((4-methylphenyl)sulfonamido)ethyl)butanamide (2d), respectively. The maximal absorption bands of dyes 1a-1d were observed at 375-447 nm, while their maximum emission peaks were situated at 495-605 nm. The optical properties showed that the fluorescence emission of dyes 1a-1d is shifted toward greater wavelengths as the system polarity (Δ f ) increased. Meanwhile, with increasing polarity of the mixed 1,4-dioxane/H 2 O system, the fluorescence intensity of dyes 1a-1d gradually decreased. Furthermore, the fluorescence intensity of 1a-1d enhanced by 12-239 fold as the polarity of 1,4-dioxane/H 2 O mixtures declined. 1a-1d had a large Stokes shift (up to 229 nm) in polar solvents in comparison to nonpolar solvents. The colocalization imaging experiments demonstrated that dyes 1a-1d (3-10 μM) were located in mitochondria, lipid droplets, lysosomes and the endoplasmic reticulum in living HeLa cells, respectively; and they could monitor the polarity fluctuation of the corresponding organelles. Consequently, this work proposes a molecular design idea with different organelle targeting capabilities based on the same new fluorophore, and this molecular design idea may provide more alternatives for polarity-sensitive fluorescent probes with organelle targeting.
Keyphrases
- ionic liquid
- single molecule
- endoplasmic reticulum
- cancer therapy
- photodynamic therapy
- living cells
- high resolution
- cell cycle arrest
- energy transfer
- quantum dots
- small molecule
- cell death
- blood pressure
- mass spectrometry
- signaling pathway
- endoplasmic reticulum stress
- reactive oxygen species
- structure activity relationship