Hemoglobin-Liposomes as Blood Replacement Fluid

Abstract

Human hemoglobin is encapsulated in unilamellar liposomes by French press extrusion in order to form hemoglobin liposomes (HBL). The mean diameter of the HBL is 50 nm by TEM. Therefore the preparation can be passed through microbial retentive filters (200 nm). The encapsulation efficiency is 11.5% and the hemoglobin content 0.52 g/100 ml for a 5.75% (v/v) dispersion. The HBL are able to bind 3.8% (v/v) 0₂ (32% (v/v) dispersion) and show the same oxygen dissociation characteristics as the hemoglobin solution. The lipid mixture consists of hydrogenated soy lecithin, which is inexpensive and stable against oxidation, and cholesterol in a molar ratio 1:l. The French press extrusion process is suitable for a scaling up.