Be sure that any vial has been brought to room temperature before opening. Ideally, the vials should be taken from the refrigerator at least a half hour before opening, and they should be left in a dessicator. Before opening any of the vials, be sure it is not at all cool to the touch. All of the cell isolation enzymes cited in this section can be repeatedly warmed to room temperature and then returned to the refrigerator as long as these precautions are followed. Once diluted with media or buffer, proteolytic enzymes can undergo autolysis.
Dissolve enzymes immediately before use.
Special care must be taken with the deoxyribonuclease. This product is very prone to shear denaturation. Avoid repeated freeze-thaw cycles. Stock solutions of trypsin should be made initially by reconstituting the enzyme in 0.001 N HCl. This solution can be diluted into the digestion medium or buffer immediately prior to use.