What do I do if I see crystals under the microscope using the Senescence β-Galactosidase Staining Kit #9860?

What do your crystals look like under the microscope? Do they look like glass shards?
We see these from time to time and they may be undissolved X-Gal which is occurring because there is an abundance of the chemical. It is important to be sure that the original solution is indeed 20mg/ml, as X-Gal can be a bit tricky to weigh out because it is so fluffy. The solutions should also be warmed to 37C prior to diluting, mixing, and adding to cells.

Were your plates wrapped in parafilm?
This is crucial to help prevent evaporation.

Have you checked the age/expiration date of your DMF?
DMF tends to expire and this can affect the solubility of the X-Gal.

We do have a solution to dissolve the crystals so you may still move forward with your experiment:
Create a 50% DMSO and water solution (please use caution when working with DMSO). Remove the staining solution, wash 1X with PBS, and add the DMSO/water solution. Once you observe dissolution of the crystals, remove the DMSO/water solution and wash your plates with 1X PBS several times before overlaying with 70% glycerol and taking your images. 

Last updated: February 26, 2024