Fluorescent probe, preparation method therefor and use thereof
Provided are a fluorescent probe, a preparation method therefor and a use thereof. The fluorescent probe responds to viscosity sensitively and specifically, can be used for the specific fluorescence labeling of proteins and can also be used in the quantification, detection or kinetic study of proteins and the imaging of cells, tissues and living bodies.
1 . A fluorescent probe, the fluorescent probe is a compound having a structure represented by formula (I-a) or (I-b), or a salt thereof,
wherein,
A is a structure of the following formula:
X—CH 2 —CH 2 - -
wherein, X is chlorine;
in formula (I-a), B is
in formula (I-b), B is
D is —NX 1 —X 2 , wherein in formula (I-a), D is —NX 1 (X 2 ), wherein, X 1 and X 2 is independently selected from hydrogen, an alkyl group, or
in formula (I-b), D is —X 2 —NX 1 , wherein, X 1 is selected from hydrogen, an alkyl group,
X 2 is
E is selected from structures of the following:
in formula (I-b),
is one selected from the following formulae (I-2-1) to (I-2-28):
in formula (I-a),
is one selected from the following formulae (I-2-29) to (I-2-38):
wherein the “alkyl” in formula (I-a) or formula (I-b) is a C 1 -C 10 linear or branched alkyl.
2 . A fluorescent probe selected from the following compounds or salts thereof:
3 . A fluorescent activated protein specific labeling method, comprising steps of contacting the fluorescent probe according to claim 1 with a target protein of a protein tag or a fusion protein tag; performing labeling reaction between the ligand moiety of the fluorescent probe and the protein tag to label the protein tag with the fluorescent probe; the labeling of the protein tag with the fluorescent probe is covalently labeling.
4 . The fluorescent probe according to claim 1 , wherein, the “alkyl” group in formula (I-a) or formula (I-b) is a C 1 -C 7 linear or branched alkyl.
5 . The fluorescent probe according to claim 1 , wherein, the “alkyl” group in formula (I-a) or formula (I-b) is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, isopentyl, 1-ethylpropyl, neopentyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, isohexyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 2-methylhexyl, 3-methylhexyl, 2,2-dimethylpentyl, 3,3-dimethylpentyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl, 3-ethylpentyl or 2,2,3-trimethylbutyl.
6 . The fluorescent activated protein specific labeling method according to claim 3 , wherein, a reaction medium of the labeling reaction is selected from a pure protein solution, a cell lysate or an in situ medium in which the target protein of a protein tag or a fusion protein tag is located; the in situ medium is intracellular media, organelle media, living tissue media, blood or body fluids.