Patent ID: 7662898

Claim:
A medical device comprising a biocompatible material comprising a polymer obtained by polymerizing a monomer composition comprising an amino acid-type betaine monomer represented by the formula (I): wherein R 1 is a hydrogen atom or a methyl group; R 2 is an alkylene group having 1 to 6 carbon atoms; each of R 3 and R 4 is independently an alkyl group having 1 to 4 carbon atoms; R 5 is an alkylene group having 1 to 4 carbon atoms; and Z is an oxygen atom or an —NH group; and a polymerizable monomer represented by the formula (II): wherein R 1 is as defined above; and R 6 is a monovalent organic group, in a weight ratio of amino acid-type betaine monomer/polymerizable monomer of from 1/99 to 100/0, wherein said medical device is selected from the group consisting of artificial blood vessels, blood dialysis membranes, catheters, blood filters, blood storage bags, and artificial organs.