RADIOSYNTHESIS OF HYDROGEL CONFINED TO HOLLOW-FIBER MEMBRANES FOR THE DESIGN OF A BIOARTIFICIAL EXTRACORPOREAL LIVER.

ROMINA HIDALGO; NORA M. VIZIOLI; EDUARDO E. SMOLKO; PABLO ARGIBAY; MARIANO GRASSELLI

Eger, Hungria

Simposio; 11th Tihany Symposium on Radiation Chemistry; 2006

International Atomic Energy Agency

Current bioartificial extra-corporeal systems are bioreactors where cells are separated from the surrounding media by porous polymeric membranes. Such porous structure controls the exchange of substances, mainly depending on their molecular size, by mass transfer processes like convection, diffusion and osmosis. The present work is focused in the design of membranes that allow differential diffusion of plasma metabolites and proteins like immunoglobulin (IgG). This design will improve the catabolites removal and also reduce possible immune response and virus contamination. In this paper we demonstrate the feasibility to synthesize hydrogels confined to the macroporous structure of membranes by radiation induced polymerization. Hollow fiber membranes are soaked in aqueous monomer solution, rinsed and irradiated submerged in oil. This procedure confine the hidrogel to the internal void volume of the membrane pores. Hydrogels of polyacrylamide and polyHEMA, molar concentrations 0.1, 0.5 and 1,  and crosslinker (CL) molar ratio of 1% and 10%, were synthesized by irradiation at 10 kGy. Hydraulic permeability and diffusion of glucose, albumin (HSA) and IgG were measured in the supported hydrogels. Polyacrylamide 0.5 M and 1% CL shows the best compromise between albumin diffusion (1.2 x 107 cm/s2) and HSA / IgG selectivity (2.16).