Use of PEI for transfection is covered by existing intellectual property rights, including US Patent 6,013,240, European Patent 0,770140, and foreign equivalents, for which Polyplus-transfection^t is the worldwide exclusive licensee. Please make sure you do not potentially infringe. Further information may be obtained by contacting Polyplus-transfection at licensing@polyplus-transfection.com. They will happily discuss licensing possibilities.Polyethyleneimine is used for various applications in products like detergents, adhesives, water treatment agents and cosmetics. It is also used as flocculating agent, enzyme carrier, wet-strength agent in the paper-making process, chelating agent form complexes with metal ions such as zinc and zirconium. It acts as scavenger for aldehydes and oxides.