Mass transfer effects in microencapsulated hybridoma cells producing monoclonal antibodies.

Rat-mouse and mouse-mouse hybridoma cell lines were used for formation of monoclonal antibodies (MAbs) in microcapsules of different sizes. Microcapsules were made of poly L-lysine-alginate hydrogel membranes. The effects of extracapsule liquid film, intracapsule and transmembrane transfer limitations of nutrients/products on system's performance were investigated. An agitation speed of 45 rpm (4 cm/s tip speed) was found to be optimal in spinner flasks to overcome liquid film resistances around capsules. Capsule sizes need to be reduced to smaller than 350 mu in order to eliminate intracapsule transfer limitations with a typical initial viable cell concentration of 0.5 x 10(5) viable cells/mL capsule. Double coating of capsules to improve strength of capsules resulted in higher transmembrane transfer resistances.