Currently, there is no simple method for defining optimal collagenase enzyme formulations for recovery of primary cells from tissue, or adherent cells from in vitro culture substrates. Crude or enriched collagenase products commonly used for these applications are minimally purified, ill-defined enzyme mixtures in which the collagenases and neutral proteases responsible for releasing cells from the extracellular matrix have variable enzyme activities and comprise only 3 to 20% of product dry weight. The DE Collagenase Optimization kit is designed to help determine the best DE Collagenase product and dose for primary cell isolation or cultured cell recovery. The products in the DE Collagenase Optimization kit are defined enzyme mixtures, containing intact forms of histolyticum collagenase and purified BP Protease (a Dispaseä-equivalent enzyme). Each DE Collagenase product is manufactured to ensure consistent enzyme activity from lot-to-lot. This consistency enables users to confidently translate results after using the DE Collagenase Optimization kit to selection of a DE Collagenase, or purified collagenase-BP Protease products to recover cells from tissue or after in vitro culture.