ABSTRACT
In 1972 Hoffman published [1] one of the first reports of the covalent immobiliza tion of heparin in order to prepare a nonthrombogenic material. Working with G. Schmer, he used the then-new cyanogen bromide chemistry [2] to immobilize heparin to radiation grafted silicone rubber. Thus began a long interest in bio molecule immobilization which went from heparin to enzymes [3] to cells [4]. For one of us (Μ. V. Sefton) the 1972 paper was our first ‘contact’ with A. S. Hoffman. A few years later, Alan came to Toronto as a keynote lecturer of the Canadian Biomaterials Society. His words of encouragement were extremely helpful to my student (M. F. A. Goosen) and myself, as we began a research program on heparin-PVA hydrogels. This paper reports on one of the latest episodes in the heparin-PVA saga.
