It has characteristic fluorescence in the ultraviolet-visible-near-infrared region, and its fluorescence properties (excitation and emission wavelengths, intensity, lifetime, polarization, etc.) can be sensitively changed with the properties of the environment, such as polarity, refractive index, viscosity, etc. a class of fluorescent molecules.
After being excited by the excitation light, it returns to the ground state from the excited singlet state, and has characteristic luminescence in the ultraviolet-visible-near-infrared region, which is called fluorescence. A class of fluorescent molecules whose fluorescence properties (excitation and emission wavelengths, intensity, lifetime, polarization, etc.) can be sensitively changed with the properties of the environment, such as polarity, refractive index, viscosity, etc., are called fluorescent probes. There are many types of fluorescent probes, which can be divided into organic and inorganic probes according to material properties, molecular probes and nanoprobes according to the size of the probes, and single-photon, two-photon and multi-photon fluorescent probes according to the excitation light source. The needles can also be classified into metal ion fluorescent probes and biomolecular fluorescent probes according to the analyte. Fluorescent probes are widely used in various detection and labeling, such as determination of metal ions, pesticide residues, biomolecule content, tracer biomolecules, labeling of macromolecules and cellular and subcellular structures.
