Enzymatic function of alginate immobilized rat hepatocytes

The use of immobilized hepatocytes represents a promising approach for the problem of detoxification in acute hepatic failure. Hepatocyte viability and detoxification function of a number of complex enzyme systems were examined before and after immobilization in alginate droplets. Detoxification function was assessed quantitatively by measuring the kinetics of several specific detoxification systems: the cytochrome P450 system, the urea cycle, and two conjugation systems. Reaction rates for all enzyme systems were similar in immobilized and nonimmobilized cells, and were in good agreement with previously published literature values. These results indicate that transport limitations do not occur in these gels and that the intrinsic reaction rate is the limiting step. Feasibility of detoxification replacement by immobilized cells is discussed using measured reaction rates.