@misc{LisdatBeissenhirtzSchelleretal.2006, author = {Lisdat, Fred and Beissenhirtz, Moritz K. and Scheller, Frieder W. and Viezzoli, Maria S.}, title = {Cystein-Mutanten der Cu,Zn-Superoxiddismutase und ihre Anwendung in Proteinelektroden f{\"u}r die Detektion von freien Sauerstoffradikalen}, series = {Wissenschaftliche Beitr{\"a}ge 2006}, volume = {11}, journal = {Wissenschaftliche Beitr{\"a}ge 2006}, issn = {0949-8214}, doi = {10.15771/0949-8214_2006_1_1}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus-216}, pages = {7 -- 11}, year = {2006}, abstract = {Das Enzym Superoxiddismutase (SOD) bietet wegen seiner hohen Reaktionsrate und seiner extrem hohen Substratspezifi t{\"a}t große Vorteile f{\"u}r eine Anwendung als Superoxidbiosensor. In dieser Arbeit wurden durch molekularbiologische Methoden Mutanten der humanen Cu,Zn-SOD gewonnen, welche ein oder zwei zus{\"a}tzliche Cystein-Reste enthielten, die eine einfache Immobilisierung des Proteins durch Bindung des Cystein-Schwefels auf Goldelektroden erm{\"o}glichten. Sechs solcher Mutanten wurden entworfen, exprimiert, aufgereinigt und elektrochemisch charakterisiert. Alle Mutanten konnten durch einen einfachen Inkubationsschritt auf Goldelektroden gebunden werden und zeigten ein quasi-reversibles elektrochemisches Ansprechen. F{\"u}r eine Mutante wurde die Anwendung als Superoxidsensor genauer untersucht und f{\"u}r beide Teilreaktionen der Dismutation ein Ansprechen des Sensors auf das Radikal gefunden. Bei Verwendung einer Teilreaktion konnte die Empfindlichkeit herk{\"o}mmlicher Monoschichtsensoren um etwa eine Gr{\"o}ßenordnung {\"u}bertroffen werden.}, language = {de} } @article{NitscheKurthDunkhorstetal.2007, author = {Nitsche, Andreas and Kurth, Andreas and Dunkhorst, Anna and P{\"a}nke, Oliver and Sielaff, Hendrik and Junge, Wolfgang and Muth, Doreen and Scheller, Frieder W. and St{\"o}cklein, Walter and Dahmen, Claudia and Pauli, Georg and Kage, Andreas}, title = {One-step selection of Vaccinia virus-binding DNA aptamers by MonoLEX}, series = {BMC Biotechnology}, volume = {7}, journal = {BMC Biotechnology}, number = {48}, issn = {1472-6750}, doi = {10.1186/1472-6750-7-48}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-6246}, pages = {12}, year = {2007}, abstract = {As a new class of therapeutic and diagnostic reagents, more than fifteen years ago RNA and DNA aptamers were identified as binding molecules to numerous small compounds, proteins and rarely even to complete pathogen particles. Most aptamers were isolated from complex libraries of synthetic nucleic acids by a process termed SELEX based on several selection and amplification steps. Here we report the application of a new one-step selection method (MonoLEX) to acquire high-affinity DNA aptamers binding Vaccinia virus used as a model organism for complex target structures.}, language = {en} } @article{TanneKracherDietzeletal.2014, author = {Tanne, Johannes and Kracher, Daniel and Dietzel, Birgit and Schulz, Burkhard and Ludwig, Roland and Lisdat, Fred and Scheller, Frieder W. and Bier, Frank Fabian}, title = {Carboxylated or Aminated Polyaniline—Multiwalled Carbon Nanotubes Nanohybrids for Immobilization of Cellobiose Dehydrogenase on Gold Electrodes}, series = {Biosensors}, volume = {4}, journal = {Biosensors}, number = {4}, issn = {2079-6374}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-5826}, pages = {370 -- 386}, year = {2014}, abstract = {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.}, language = {en} }