Two-photon probe for real-time monitoring of intracellular free zinc ions, method for preparing the probe and method for real-time monitoring of intracellular free zinc ions using the probe

1. A two-photon probe for real-time monitoring of intracellular free zinc ions, represented by Formula 1:

wherein R is H or OCH 3 .

2. A method for preparing a two-photon probe for real-time monitoring of intracellular free zinc ions, represented by Formula 1:

wherein R is H or OCH 3 ,

the method comprising (a) adding the compound of Formula 2:

to an organic solvent and stirring the mixture, and (b) reacting the compound of Formula 2 with the compound of Formula 3:

wherein R is H or OCH 3 ,

by contacting the mixture of step (a) with the compound of formula 3 to form a reaction product.

3. The method of claim 2 , further comprising isolating the compound of Formula 1 from the reaction product after step (b).

4. The method of claim 2 , wherein the organic solvent is selected from 1-hydroxybenzotriazole, 1,3-dicyclohexylcarbodiimide and a mixture thereof.

5. The method of claim 3 , wherein the compound of Formula 1 is isolated by extraction.

6. A method for real-time monitoring of intracellular free zinc ions, the method comprising injecting the two-photon probe of claim 1 into cells of interest and observing two-photon excitation fluorescence (TPEF) images of the cells.

7. The method of claim 6 , wherein the TPEF images are obtained from the cells at a depth of 80 to 150 μm in live tissues.

8. The method of claim 6 , wherein the TPEF images are observed for longer than 1,000 seconds.