Regensburg 2019 – wissenschaftliches Programm
MM 20.33: Poster
Dienstag, 2. April 2019, 18:30–20:00, Poster C
Nanoporous gold as carrier for electrochemically assisted immobilization of redox-active enzyme using a cationic binding module — •Elisabeth Hengge1, Eva-Maria Steyskal1, Alexander Dennig2, Bernd Nidetzky2, and Roland Würschum1 — 1Inst. of Mater. Phys., TU Graz — 2Inst. of Biotechnol. and Biochem. Eng. , TU Graz
An attractive application of nanoporous metals is in the field of biocatalysis, among which an important issue is related to the immobilization of enzymes that catalyse redox reactions. Here, we combine tailor-made enzymes with a nanoporous metal electrode under electrochemical control to enable regulation of the binding mechanisms and in-situ monitoring of underlying kinetics. An AuAg master alloy was used to produce self-supporting nanoporous gold samples by dealloying . The pore size was optimized for immobilization by thermal annealing. As enzyme, the cytochrome P450 BM3  fused to ZBasic2 has been chosen. It is already known that this binding module provides the possibility for oriented and selective immobilization on non-metallic carriers . The influence of the surface charge on the immobilization is studied in-situ in an electrochemical cell. Simultaneously, we determine the decrease of enzyme concentration in the electrolyte by UV/VIS spectroscopy. The biocatalytic activity of this new hybrid material was investigated by using lauric acid as a model substrate.  Bolivar JM, Nidetzky B, Langmuir 28 (2012) 10040.  Valikhani D et al. Biotechnol. Bioeng. 115 (2018) 2416.  Steyskal EM et al. Phys. Chem. Chem. Phys. 19 (2017) 29880.