Varga, S.Malcata, F. Xavier2011-10-142011-10-141996VARGA, S. ; MALCATA, F. Xavier - Enhancement of product selectivity via enzyme immobilization in sequential degradation reactions of polymeric substrates. Bioprocess and Biosystems Engineering. ISSN 0178-515X. 15:4 (1996) 189-194http://hdl.handle.net/10400.14/6105The balance equations pertaining to the modelling of a slap-shaped bead containing immobilized enzyme uniformly distributed which catalyzes the sequential reactions of degradation of a polymeric substrate were written and analytically solved in dimensionless form. The effect of the Thiele modulus on the selectivity of consumption of each multimeric product was studied for a simple case. Whereas plain diffusional regime leads to lower selectivities than plain kinetic regime, improvements in selectivity of species A i relative to species Ai+1 may be obtained at the expense of higher Thiele moduli within a limited range when the diffusivity of A i is larger than that of A i +1, or when the pseudo first order kinetic constant describing the rate of consumption of A i is lower than that of Ai+1.engjournal article10.1007/BF00369480