Zinquin ethyl ester is a cell membrane-penetrating and selective fluorescent probe for zinc ions that measures intracellular levels of Zn(2+) and Ca(2+) ions and can be used to stain early embryos.

RPE cell uptake of Zn2+ experiment
a. Solution preparation: Use DMSO to prepare a 10 mM Zinquin ethyl ester stock solution. For example, weigh 1 mg of Zinquin ethyl ester and add 0.4825 mL of DMSO.
Note: The prepared stock solution should be stored in aliquots to avoid repeated freezing and thawing. Unused stock solution should be divided into aliquots of single-use volume and stored at -20℃ in the dark.
b. Operation steps:
1. RPE cells were incubated with 0 ~ 18 nM Zn2+ in serum-free MEM without Zn2+ detection level for 60 minutes.
2. After removing extracellular Zn2+ from the culture, the cells were loaded with 2.5 mM zinc fluorescent sensor Zinquin ethyl ester for 30 minutes.
3. Observe the fluorescent Zinquin-Zn2+ complex under a fluorescence microscope with excitation at 364 nm and emission at 385 nm.

The above information is based on published literature. Experimental procedures should be appropriately modified to meet specific research demands.

H2O: < 0.1 mg/mL (insoluble)

DMSO: 50 mg/mL (120.63 mM), Sonication is recommended.