Preparation

1. Add calculated amount of X-gal to a light-tight container.

CRITICALContainer must be light-tight to avoid degradation of X-gal.

2. Add the calculated amount of DMSO.

3. Wait for full dissolution.

4. OPTIONAL Distribute into smaller aliquots for storage.

This step will reduce the number of freeze-thaw cycles an individual sample will undergo.

5. Store at -20°C, avoid light.