TY  - JOUR
A1  - Spricigo, Roberto
A1  - Richter, Claudia
A1  - Leimkühler, Silke
A1  - Gorton, Lo
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
T1  - Sulfite biosensor based on osmium redox polymer wired sulfite oxidase
N2  - A biosensor, based on a redoxactive osmium polymer and sulfite oxidase on screen-printed electrodes, is presented here as a promising method for the detection of sulfite. A catalytic oxidative current was generated when a sample containing sulfite was pumped over the carbon screen-printed electrode modified with osmium redox polymer wired sulfite oxidase. A stationary value was reached after approximately 50 s and a complete measurement lasted no more than 3 min. The electrode polarized at -0.1 V (vs. Ag vertical bar AgCl 1M KCl) permits minimizing the influence of interfering substances, since these compounds can be unspecific oxidized at higher potentials. Because of the good stability of the protein film on the electrode surface, a well functioning biosensor-flow system was possible to construct. The working stability and reproducibility were further enhanced by the addition of bovine serum albumin generating a more long-term stable and biocompatible protein environment. The optimized biosensor showed a stable signal for more than a week of operation and a coefficient of variation of 4.8% for 12 successive measurements. The lower limit of detection of the sensor was 0.5 mu M sulfite and the response was linear until 100 mu M. The high sensitivity permitted a 1:500 dilution of wine samples. The immobilization procedure and the operational conditions granted minimized interferences. Additionally, repeating the immobilization procedure to form several layers of wired SO further increased the sensitivity of such a sensor. Finally. the applicability of the developed sulfite biosensor was tested on real samples, such as white and red wines.
Y1  - 2010
UR  - http://www.sciencedirect.com/science/journal/09277757
U6  - https://doi.org/10.1016/j.colsurfa.2009.09.001
SN  - 0927-7757
ER  - 
TY  - JOUR
A1  - Frasca, Stefano
A1  - von Graberg, Till
A1  - Feng, Jiu-Ju
A1  - Thomas, Arne
A1  - Smarsly, Bernd M.
A1  - Weidinger, Inez M.
A1  - Scheller, Frieder W.
A1  - Hildebrandt, Peter
A1  - Wollenberger, Ursula
T1  - Mesoporous indium tin oxide as a novel platform for bioelectronics
N2  - Stable immobilization and reversible electrochemistry of cytochrome c in a tranparent indium tin oxide film with a well-defined mesoporosity (mpITO) is demonstrated. the transparency and good conductivity, in combination with the large surface area of mpITO, allow the incorporation of a high amount of elelctroactive biomolecules and their electrochemical and spectroscopic investigation. UV/Vis and resonance Raman spectroscopy, in combination with direct protein voltammetry are employed for the characterization of cytochrome c immobilized in the mpITO and reveal no perturbant of the structural of the integrity of the redox protein. The potential of this modified material as a biosensor detection of superoxide anions is also demonstrated.
Y1  - 2010
UR  - http://www3.interscience.wiley.com/journal/122208635/home
U6  - https://doi.org/10.1002/cctc.201000047
SN  - 1867-3880
ER  - 
TY  - JOUR
A1  - Baeumner, Antje J.
A1  - Gauglitz, Guenter
A1  - Scheller, Frieder W.
T1  - Focus on bioanalysis
N2  - Editoria
Y1  - 2010
UR  - http://www.springerlink.com/content/100417
U6  - https://doi.org/10.1007/s00216-010-4203-9
SN  - 1618-2642
ER  -