Corning Matrigel matrix is a solubilized basement membrane preparation extracted from the Engelbreth-Holm-Swarm (EHS) mouse sarcoma, a tumor rich in extracellular matrix (ECM) proteins, including Laminin (a major component), Collagen IV, heparan sulfate proteoglycans, entactin/nidogen, and a number of growth factors. Quality Mouse colonies routinely screened for pathogens via Mouse Antibody Production (MAP) testing Extensive PCR testing is performed to screen for a number of pathogens Tested and found negative for bacteria, fungi, and mycoplasma Protein concentrations determined by Lowry method Endotoxin units measured by Limulus Amoebocyte Lysate assay Matrigel Matrix gel stability is tested for a period of 14 days at 37°C Biological activity is determined for each lot using a neurite outgrowth assay. Source Engelbreth-Holm-Swarm (EHS) mouse tumor Preparation and Storage Store at -20°C. Avoid multiple freeze-thaws. Click here for Corning Matrigel Lot Selection and Reservation. For Customers in California only: WARNING Please refer to Safety Data Sheet (SDS) Section 15 for more information regarding California Proposition 65.