The invention provides a modified haem which is chemically coupled with a polyalkylene glycol methyl ether or an .omega.-amino derivative thereof through at least one of the two carboxyl groups in said haem molecule. The modified haem has a peroxidase activity and is soluble in water or various organic...http://www.google.com.au/patents/US4822877?utm_source=gb-gplus-sharePatent US4822877 - Modified haem
