Desalination 199 (2006) 228–229 Presented at EUROMEMBRANE 2006, 24–28 September 2006, Giardini Naxos, Italy. 0011-9164/06/$– See front matter © 2006 Elsevier B.V. All rights reserved. A new combined method to localize enzyme immobilized in polymeric membranes and evaluate its activity in situ Silvia Mazzuca a , Lidietta Giorno b *, Antonia Spadafora a , Rosalinda Mazzei b , Enrico Drioli b a Department of Ecology, University of Calabria, Via P. Bucci 6/B, 87036 Rende, Italy b Institute on Membrane Technology, ITM-CNR, C/o University of Calabria, Via P. Bucci 17/C, 87036 Rende (CS), Italy email: l.giorno@itm.cnr.it; s.mazzuca@unical.it Received 26 October 2005; accepted 2 March 2006 Keywords: Enzyme immobilization; Enzyme activity in situ; Immunolocalization; Polymeric membrane 1. Introduction Biocatalytic membrane reactors using immobilized enzymes is a well-documented technology located at an emerging step in a graph of research efforts vs technology devel- opment. The immobilization of enzymes has proven to increase their stability and it has recently been shown that the widely observed inverse relationship between stability and activity is not a general rule. Various methods are used to immobilize enzymes in membranes and usually the amount of immobilized enzyme is calculated by mass balance between the initial solution (feed) and final solutions (retentate and permeate). The catalytic properties are then measured as observed reaction rate on the basis of the reaction product in the bulk solution. At authors’ knowledge, there is not yet published information on where the enzyme is immobilized within the polymeric membrane matrix. 2. Results and discussion In this study, a new combined method revealing enzyme activity in situ all together the immunolocalization of the sites of immobilization on polymeric membrane has been developed. For this purpose b-glucosidase (from almond and olive fruit) was selected among other enzymes because of its suitable target for protein engineering to address the problems of biomass production in agriculture and forestry, biomass conversion in biotechnology, as well as substrate processing in pharmaceutical. b-glucosidases were immobi- lized by physical method in asymmetric capillary *Corresponding author. doi:10.1016/j.desal.2006.03.054