Carboxylated or Aminated Polyaniline—Multiwalled Carbon Nanotubes Nanohybrids for Immobilization of Cellobiose Dehydrogenase on Gold Electrodes
Johannes Tanne,
Daniel Kracher,
Birgit Dietzel,
Burkhard Schulz,
Roland Ludwig,
Fred Lisdat,
Frieder W. Scheller,
Frank F. Bier
Affiliations
Johannes Tanne
Fraunhofer Institute for Cell Therapy and Immunology (IZI-BB), Branch Bioanalytics and Bioprocesses Potsdam-Golm, Am Mühlenberg 13, 14476 Potsdam, Germany
Daniel Kracher
Food Biotechnology Laboratory, Department of Food Sciences and Technology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
Birgit Dietzel
Institute for Thin Film and Microsensoric Technology, Kantstr. 55, 14513 Teltow, Germany
Burkhard Schulz
Institute for Thin Film and Microsensoric Technology, Kantstr. 55, 14513 Teltow, Germany
Roland Ludwig
Food Biotechnology Laboratory, Department of Food Sciences and Technology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
Fred Lisdat
Biosystems Technology, Institute of Applied Life Sciences, Technical University of Applied Sciences Wildau, Hochschulring 1, 15745 Wildau, Germany
Frieder W. Scheller
Fraunhofer Institute for Cell Therapy and Immunology (IZI-BB), Branch Bioanalytics and Bioprocesses Potsdam-Golm, Am Mühlenberg 13, 14476 Potsdam, Germany
Frank F. Bier
Fraunhofer Institute for Cell Therapy and Immunology (IZI-BB), Branch Bioanalytics and Bioprocesses Potsdam-Golm, Am Mühlenberg 13, 14476 Potsdam, Germany
Polymer-multiwalled carbon nanotube (MWCNT) nanohybrids, which differ in surface charge have been synthesized to study the bioelectrocatalysis of adsorbed cellobiose dehydrogenase (CDH) from Phanerochaete sordida on gold electrodes. To obtain negatively charged nanohybrids, poly(3-amino-4-methoxybenzoic acid-co-aniline) (P(AMB-A)) was covalently linked to the surface of MWCNTs while modification with p-phenylenediamine (PDA) converted the COOH-groups to positively charged amino groups. Fourier transform infrared spectroscopy (FTIR) measurements verified the p-phenylenediamine (PDA) modification of the polymer-CNT nanohybrids. The positively charged nanohybrid MWCNT-P(AMB-A)-PDA promoted direct electron transfer (DET) of CDH to the electrode and bioelectrocatalysis of lactose was observed. Amperometric measurements gave an electrochemical response with KMapp = 8.89 mM and a current density of 410 nA/cm2 (15 mM lactose). The catalytic response was tested at pH 3.5 and 4.5. Interference by ascorbic acid was not observed. The study proves that DET between the MWCNT-P(AMB-A)-PDA nanohybrids and CDH is efficient and allows the sensorial detection of lactose.
