Abstract
An unsaturated lipid made from 2,4-octadecadienoic acid was used as a component of phosholipid vesicles. The vesicles (0.2 μm ø) was prepared by an extrusion method, and the unsaturated lipid was polymerized with γ-ray. Vesicles constructed from the poly lipid show enormous stability during long term storage in frozen state and can be handled easily. Negative effect could not be confirmed in vitro tests. This system satisfies all the physiological conditions, such as oxygen transport ability and solution properties as a blood substitute.