A method for removing endotoxin bound to a protein that comprises the steps: (a) Binding the protein to a cation exchange； (b) Washing the resin with water； (c) Eluting the endotoxin using a low-ionic strength solution in the absence of added surfactant； (d) Eluting the protein with a high-ionic strength solution. The protein can be lactoferrin which can be used in the treatment of wounds.
