System design of a bioartificial liver with a high performance hemodialyzer as an immunoisolator using a mathematical kinetic model.

We propose a new bioartificial liver (BAL) system equipped with a high performance hemodialyzer to act as an immunoisolation device. We discuss the design of the BAL system using a mathematical kinetic model with the experimentally obtained mass-transfer performances of various hemodialyzers. The mass transfer resistances of the hemodialyzers did not adversely influence the ammonia-removal and bioactive-substance-supply performances of the BAL system. A suitable hemodialyzer for the BAL system is available even at present using an engineering design. The remaining problems to be overcome before realizing clinical use of the BAL system are to increase the rate constant of the first order reaction of the BAL for ammonia metabolism and to develop a new method of blood access that can be used safely with long term reliability at a high blood flow rate (ca. 556 ml/min).