TY  - JOUR
A1  - Fandrich, Artur
A1  - Buller, Jens
A1  - Memczak, Henry
A1  - Stoecklein, W.
A1  - Hinrichs, K.
A1  - Wischerhoff, E.
A1  - Schulz, B.
A1  - Laschewsky, André
A1  - Lisdat, Fred
T1  - Responsive Polymer-Electrode Interface-Study of its Thermo- and pH-Sensitivity and the Influence of Peptide Coupling
JF  - Electrochimica acta : the journal of the International Society of Electrochemistry (ISE)
N2  - This study introduces a thermally responsive, polymer-based electrode system. The key component is a surface-attached, temperature-responsive poly(oligoethylene glycol) methacrylate (poly(OEGMA)) type polymer bearing photoreactive benzophenone and carboxy groups containing side chains. The responsive behavior of the polymer in aqueous media has been investigated by turbidimetry measurements. Polymer films are formed on gold substrates by means of the photoreactive 2(dicyclohexylphosphino)benzophenone (DPBP) through photocrosslinking. The electrochemical behavior of the resulting polymer-substrate interface has been investigated in buffered [Fe(CN)6](3-)/[Fe (CN)6](4-)solutions at room temperature and under temperature variation by cyclic voltammetry (CV). The CV experiments show that with increasing temperature structural changes of the polymer layer occur, which alter the output of the electrochemical measurement. Repeated heating/cooling cycles analyzed by CV measurements and pH changes analyzed by quartz crystal microbalance with dissipation monitoring (QCM-D) reveal the reversible nature of the restructuring process. The immobilized films are further modified by covalent coupling of two small biomolecules - a hydrophobic peptide and a more hydrophilic one. These attached components influence the hydrophobicity of the layer in a different way the resulting change of the temperature-caused behavior has been studied by CV indicating a different state of the polymer after coupling of the hydrophobic peptide.
KW  - Stimuli-responsive materials
KW  - electroanalysis
KW  - modified electrode
KW  - bioreceptors
KW  - peptides
KW  - surface modification
KW  - cyclic voltammetry
KW  - IR ellipsometry
KW  - quartz crystal microbalance
Y1  - 2017
U6  - https://doi.org/10.1016/j.electacta.2017.01.080
SN  - 0013-4686
SN  - 1873-3859
VL  - 229
SP  - 325
EP  - 333
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Fandrich, Artur
A1  - Buller, Jens
A1  - Schäfer, Daniel
A1  - Wischerhoff, Erik
A1  - Laschewsky, André
A1  - Lisdat, Fred
T1  - Electrochemical characterization of a responsive macromolecular interface on gold
JF  - Physica status solidi : A, Applications and materials science
N2  - This study reports on the investigation of a thermoresponsive polymer as a thin film on electrodes and the influence of coupling a peptide and an antibody to the film. The utilized polymer from the class of poly(oligoethylene glycol)-methacrylate polymers (poly(OEGMA)) with carboxy functions containing side chains was synthesized and properly characterized in aqueous solutions. The dependence of the cloud point on the pH of the surrounding media is discussed. The responsive polymer was immobilized on gold electrodes as shown by electrochemical, quartz crystal microbalance (QCM), and atomic force microscopy (AFM) techniques. The temperature dependent behavior of the polymer covalently grafted to gold substrates is investigated using cyclic voltammetry (CV) in ferro-/ferricyanide solution. Significant changes in the slope of the temperature-dependence of the voltammetric peak current and the peak separation values clearly indicate the thermally induced conformational change on the surface. Finally, a biorecognition reaction between a short FLAG peptide (N-Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys-C) covalently immobilized on the polymer interface and the corresponding IgG antibody was performed. The study shows that the responsiveness of the electrode is retained after peptide coupling and antibody binding, although the response is diminished.
KW  - biorecognition reactions
KW  - cyclic voltammetry
KW  - electrodes
KW  - gold
KW  - interfaces
KW  - responsive polymers
Y1  - 2015
U6  - https://doi.org/10.1002/pssa.201431698
SN  - 1862-6300
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1359
EP  - 1367
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Fandrich, Artur
A1  - Buller, Jens
A1  - Wischerhoff, Erik
A1  - Laschewsky, André
A1  - Lisdat, Fred
T1  - Electrochemical detection of the thermally induced phase transition of a thin stimuli-responsive polymer film
JF  - ChemPhysChem : a European journal of chemical physics and physical chemistry
KW  - cyclic voltammetry
KW  - electrochemical impedance spectroscopy
KW  - polymers
KW  - surface chemistry
KW  - surface plasmon resonance
Y1  - 2012
U6  - https://doi.org/10.1002/cphc.201100924
SN  - 1439-4235
VL  - 13
IS  - 8
SP  - 2020
EP  - 2023
PB  - Wiley-VCH
CY  - Weinheim
ER  -