Electron microscopical study of the structure of liposome-type artificial red blood cells stabilized with carboxymethylchitin.

Stable liposome-type artificial red blood cells containing either an aqueous bromothymol solution or erythrocyte haemolysate were produced using carboxymethylchitin as a stabilizer. The structure of the resulting vesicles was investigated by electron microscopy after freeze-fracturing, freeze-substitution and negative staining. The vesicles were not homogeneous but contained unilamellar and multilamellar structures. The maximum size was about 2 microns; most vesicles were about 200-500 nm in size. The carboxymethylchitin did not yield a continuous layer but rather occurred in patches on the membrane surface probably forming a mesh-like layer over the entire liposome surface.