Construction and performance of a minibioreactor suitable as experimental bioartificial liver

This work deals with the construction and performance of a hollow fiber-based minibioreactor (MBR). Due to its simple design and the utilization of standard materials, it could serve as a suitable tool to evaluate the behavior and performance of cold preserved or cultured hepatocytes in bioartificial liver devices. The system consists of 140 fiber capillaries through which goat blood is pumped at a flow of 9 mL/min. The cell compartment contains 90 x 10(6) rat hepatocytes (volume 10 mL) and an internal oxygenator made of silicone tubing. To test the in vitro function of the system, 2-h perfusion experiments were performed, the evolution of hematocrit, plasma and extra-fiber fluid osmolality, and plasma urea and creatinine concentrations were evaluated. The detoxication efficiency of an ammonia overload was tested, showing that the system has enough capacity to remove ammonium. Also, the MBR oxygen transfer capacity to hepatocytes was tested, showing that the cells received an adequate oxygen supply.