title: Monitoring of the Enzymatically Catalyzed Degradation of Biodegradable Polymers by Means of Capacitive Field-Effect Sensors.
abstract: Designing novel or optimizing existing biodegradable polymers for biomedical applications requires numerous tests on the effect of substances on the degradation process. In the present work, polymer-modified electrolyte-insulator-semiconductor (PMEIS) sensors have been applied for monitoring an enzymatically catalyzed degradation of polymers for the first time. The thin films of biodegradable polymer poly(D,L-lactic acid) and enzyme lipase were used as a model system. During degradation, the sensors were read-out by means of impedance spectroscopy. In order to interpret the data obtained from impedance measurements, an electrical equivalent circuit model was developed. In addition, morphological investigations of the polymer surface have been performed by means of in situ atomic force microscopy. The sensor signal change, which reflects the progress of degradation, indicates an accelerated degradation in the presence of the enzyme compared to hydrolysis in neutral pH buffer media. The degradation rate increases with increasing enzyme concentration. The obtained results demonstrate the potential of PMEIS sensors as a very promising tool for in situ and real-time monitoring of degradation of polymers.
authors.affiliation: †Institute of Nano- and Biotechnologies (INB), FH Aachen, Jülich, Germany.|‡Peter Grünberg Institute (PGI-8), Forschungszentrum Jülich GmbH, Jülich, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Schusser
authors.affiliation: †Institute of Nano- and Biotechnologies (INB), FH Aachen, Jülich, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Krischer
authors.affiliation: †Institute of Nano- and Biotechnologies (INB), FH Aachen, Jülich, Germany.|‡Peter Grünberg Institute (PGI-8), Forschungszentrum Jülich GmbH, Jülich, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Bäcker
authors.affiliation: †Institute of Nano- and Biotechnologies (INB), FH Aachen, Jülich, Germany.|‡Peter Grünberg Institute (PGI-8), Forschungszentrum Jülich GmbH, Jülich, Germany.
authors.forename: Arshak
authors.initials: A
authors.lastname: Poghossian
authors.affiliation: §Department of Physics and Astronomy, Catholic University Leuven, Leuven, Belgium.|∥Institute for Materials Research (IMO), Hasselt University, Diepenbeek, Belgium.
authors.forename: Patrick
authors.initials: P
authors.lastname: Wagner
authors.affiliation: †Institute of Nano- and Biotechnologies (INB), FH Aachen, Jülich, Germany.|‡Peter Grünberg Institute (PGI-8), Forschungszentrum Jülich GmbH, Jülich, Germany.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Schöning
mesh_terms: D055162:Biocatalysis; D001672:Biocompatible Materials; D015374:Biosensing Techniques; D018625:Microscopy, Atomic Force; D011108:Polymers / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D011108:Polymers