Semipermeable Aqueous Microcapsules: Iv. Nonthrombogenic Microcapsules With Heparin-Complexed Membranes

Stable nonthrombogenic microcapsules of 4 to 200 μ mean diameter consisting of a protein or detoxifying agent enclosed within thin semipermeable benzal-konium–heparin complexed polymer membranes were prepared. Such microcapsules did not cause clot formation in a nonthrombogenic extracorporeal shunt chamber when perfused for several hours by circulating blood which had normal clotting time. The enclosed enzyme retained its catalytic activity.