Enzymatic hydrolysis of poly(ethyleneterephthalate) used for and analysed by pore modification of track-etched membranes

Publication date: Available online 8 July 2017
Source:New Biotechnology
Author(s): Caroline Gamerith, Martyna Gajda, Andreas Ortner, Enrique Herrero Acero, Georg M. Guebitz, Mathias Ulbricht
The potential of limited enzymatic poly(ethylene terephthalate) (PET) surface hydrolysis for the modification of track-etched (TE) membranes was investigated. Cutinases 1 and 2 from Thermobifida cellulosilytica as well as a fusion protein of cutinase 1 with the polymer binding module from the polyhydroxyalkanoate depolymerase of Alcaligenes faecalis (Thc_Cut1_PBM) were shown to hydrolyse highly crystalline PET TE membranes with a pore diameter of ∼120nm at very narrow size distribution. Furthermore the effects of surface chemistry were investigated by comparison of enzymatic hydrolysis by Thc_Cut1_PBM of "as received" PET TE membranes with two surface functionalized versions towards a "hydrophilic" and a more "hydrophobic" surface. The effects of adsorbed protein and the efficacy of cleaning steps after enzymatic treatment were elucidated by complementary methods for surface analysis and membrane characterization. With the optimized cleaning protocol, all adsorbed protein could be removed from the enzyme-treated membranes and effects of chemical surface functionalization of the PET TE membranes were demonstrated. The highest efficiency of enzymatic surface hydrolysis was observed for the original PET TE membranes, leading to an 0.36 % weight loss corresponding to a removal of ∼3nm PET from the entire surface of the porous membrane. This correlates very well with the measured increase of barrier pore diameter by 4nm (a radius reduction? of 2 nm), leading to about a two-fold increased water permeability.

Graphical abstract

from # All Medicine by Alexandros G. Sfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2tZ6gig
via IFTTT