This liquid trypsin formula contains EDTA and phenol red. Gibco Trypsin-EDTA is made from trypsin powder, an irradiated mixture of proteases from porcine pancreas. Due to its digestive strength, trypsin is widely used for cell dissociation, routine cell culture passaging, and primary tissue dissociation. The trypsin concentration required for dissociation varies depending on cell type and experimental requirements.