TY - JOUR A1 - Buller, Jens A1 - Laschewsky, André A1 - Lutz, Jean-Francois A1 - Wischerhoff, Erik T1 - Tuning the lower critical solution temperature of thermoresponsive polymers by biospecific recognition JF - Polymer Chemistry N2 - A thermosensitive statistical copolymer based on oligo(ethylene glycol) methacrylates incorporating biotin was synthesized by free radical copolymerisation. The influence of added avidin on its thermoresponsive behaviour was investigated. The specific binding of avidin to the biotinylated copolymers provoked a marked increase of the lower critical solution temperature. Y1 - 2011 U6 - https://doi.org/10.1039/c1py00001b SN - 1759-9954 VL - 2 IS - 7 SP - 1486 EP - 1489 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Buller, Jens A1 - Laschewsky, André A1 - Wischerhoff, Erik T1 - Photoreactive oligoethylene glycol polymers - versatile compounds for surface modification by thin hydrogel films JF - Soft matter N2 - Solid surfaces are modified using photo-crosslinkable copolymers based on oligo(ethylene glycol) methacrylate (OEGMA) bearing 2-(4-benzoylphenoxy) ethyl methacrylate (BPEM) as a photosensitive crosslinking unit. Thin films of about 100 nm are formed by spin-coating these a priori highly biocompatible copolymers onto silicon substrates. Subsequent UV-irradiation assures immobilization and crosslinking of the hydrogel films. Their stability is controlled by the number of crosslinker units per chain and the molar mass of the copolymers. The swelling of the hydrogel layers, as investigated by ellipsometry, can be tuned by the crosslinker content in the copolymer. If films are built from the ternary copolymers of OEGMA, BPEM and 2-(2-methoxyethoxy) ethyl methacrylate (MEO(2)MA), the hydrogel films exhibit a swelling/deswelling transition of the lower critical solution temperature (LCST) type. The observed thermally induced hydrogel collapse is fully reversible and the onset temperature of the transition can be tuned at will by the copolymer composition. Different from analogously prepared thermo-responsive hydrogel films of photocrosslinked poly(N-isopropylacrylamide), the swelling-deswelling transition occurs more gradually, but shows no hysteresis. Y1 - 2013 U6 - https://doi.org/10.1039/c2sm26879e SN - 1744-683X VL - 9 IS - 3 SP - 929 EP - 937 PB - Royal Society of Chemistry CY - Cambridge ER - TY - CHAP A1 - Buller, Jens A1 - Laschewsky, André A1 - Wischerhoff, Erik A1 - Fandrich, Artur A1 - Lisdat, Fred T1 - Smart synthetic macromolecules recognizing proteins T2 - Abstracts of papers : joint conference / The Chemical Institute of Cananda, CIC, American Chemical Society, ACS Y1 - 2012 SN - 0065-7727 VL - 244 PB - American Chemical Society CY - Washington 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 - TY - JOUR A1 - Heydari, Esmaeil A1 - Buller, Jens A1 - Wischerhoff, Erik A1 - Laschewsky, André A1 - Döring, Sebastian A1 - Stumpe, Joachim T1 - Label-Free biosensor based on an all-polymer DFB laser JF - Advanced optical materials KW - label-free biosensors KW - DFB lasers KW - active optical resonators KW - hydrogels KW - semiconducting polymers Y1 - 2014 U6 - https://doi.org/10.1002/adom.201300454 SN - 2195-1071 VL - 2 IS - 2 SP - 137 EP - 141 PB - Wiley-VCH CY - Weinheim ER -