Effective release of cells from tissue requires the action of both collagenase enzymes and the neutral protease. Collagenase is activated by four grams of calcium (Ca2+) per mole of the enzyme. The culture filtRate is thought to contain at least 7 different proteases ranging in molecular weight from 68-130 kDa. The pH optimum is 6.3-8.8. The enzyme is typically used to digest the connective components in tissue samples to libeRate individual cells. Collagenase treatment can cause some cells to die. Typically, concentRations varying from 0.1 to 5 mg/mL are used for digestion. The duRation of reaction can vary from 15 minutes to several hours for satisfactory cell dissociation without causing too much cell death. Zn2+ is required for activity. This product is used if the collagenase does not require a significant protease activity.http://www.creative-enzymes.com/product/Native-Collagenase-Protease-Inhibitor_1110.html