Preparation and Surface Characterization of Carboxymethylchitin-Incorporated Submicron Bilayer-Lipid Membrane Artificial Cells (Liposomes) Encapsulating Hemoglobin

Abstract

In view of the desirability to increase the survival time of the liposome-based artificial red blood cells in vivo, bovine hemoglobin-loaded liposomes (LEHb) are incorporated with a polyanionic polymer, a highly substituted type of carboxymethylchitin (CMC). The liposomes are prepared by a modified Reverse Phase Evaporation technique and then purified using a Sepharose 4B column. A comparative study between experimental techniques for the determination of adsorption efficiency suggests that FT-IR spectroscopy gives a more accurate quantitative adsorption index while the chitinase-based enzymatic assay should be used as a qualitative detection tool. The overall composition of the bilayer(s) can be approximated by that of the natural (RBC) membrane in terms of total lipids and carbohydrates at 87.8% (phospholipids and cholesterol) and 12.2% CMC respectively.