How should I store my purified collagenase?

This product is stable for at least two years from date of manufacture if stored unopened between -15 to – 25°C.
Internal studies have shown the reconstituted enzyme is stable as a frozen solution between -15 to – 25°C for at least 1 year as long as no other protease enzymes had been added to the solution. Additional studies have shown the reconstituted collagenase was successfully frozen and thawed three times as a concentrated or dilute solution without apparent loss of potency as assessed by the CDA assay. The product is shipped on dry ice to provide the most stable conditions during shipment.