Methods of Immobilization of Proteins to Polymethylmethacrylate

An extracorporeal hemoperfusion chamber for insertion into the peripheral circulatory system has previously been described. In 4 to 6 hours perfusion its aim is to exert a subtractive, selective effect on the blood and to stimulate immunocompetent cells. The chamber is made from polymethylmethacrylate (PMMA). Two general methods for immobilization are described here. The first is based on hydrazinolysis of the PMMA surface. Biologically active substances can be attached through diacylhydrazine bridges, amine bonds and amide groups to the PMMA surface. In the second method carboxyl groups are generated by hydrolysis of the PMMA methyl ester groups. The biologically active substance is immobilized using diamine or dialdehyde coupling agents. Methods are provided to attach the substances to the PMMA either via their carboxyl or via their amino groups.