Influence of Fibroin Membrane Composition and Curing Parameters on the Performance of a Biodegradable Enzymatic Biosensor Manufactured from Silicon‐Free Carbon

• Published in: Physica status solidi. A, Applications and materials science Applications and materials science, 2023-11, Vol.220 (22), p.n/a
• Main Authors: Janus, Kevin A., Achtsnicht, Stefan, Tempel, Laura, Drinic, Aleksander, Kopp, Alexander, Keusgen, Michael, Schöning, Michael J.
• Format: Article
• Language: English
• Subjects: amperometric biosensors; Biocompatibility; biocompatible; biodegradable; Biodegradable materials; Biomedical materials; Biosensors; Buffer solutions; Carbon; Composition; Curing; Electrical measurement; Electrodes; Encapsulation; encapsulation materials; fibroin; Glucose oxidase; Hydrogen peroxide; Leakage current; Membranes; Parameters; Polylactic acid; Substrates
• ISSN: 1862-6300; 1862-6319
• DOI: 10.1002/pssa.202300081

Herein, fibroin, polylactide (PLA), and carbon are investigated for their suitability as biocompatible and biodegradable materials for amperometric biosensors. For this purpose, screen‐printed carbon electrodes on the biodegradable substrates fibroin and PLA are modified with a glucose oxidase membrane and then encapsulated with the biocompatible material Ecoflex. The influence of different curing parameters of the carbon electrodes on the resulting biosensor characteristics is studied. The morphology of the electrodes is investigated by scanning electron microscopy, and the biosensor performance is examined by amperometric measurements of glucose (0.5–10 mM) in phosphate buffer solution, pH 7.4, at an applied potential of 1.2 V versus a Ag/AgCl reference electrode. Instead of Ecoflex, fibroin, PLA, and wound adhesive are tested as alternative encapsulation compounds: a series of swelling tests with different fibroin compositions, PLA, and Ecoflex has been performed before characterizing the most promising candidates by chronoamperometry. Therefore, the carbon electrodes are completely covered with the particular encapsulation material. Chronoamperometric measurements with H2O2 concentrations between 0.5 and 10 mM enable studying the leakage current behavior. A silicon‐free carbon paste, screen‐printed on the biodegradable substrates fibroin and polylactide, is solidified with different curing profiles. The electrodes are modified with the enzyme glucose oxidase to form a biosensor and evaluated for their sensitivity via chronoamperometric measurements. Furthermore, the ability of polylactide, wound adhesive, Ecoflex, and fibroin to serve as biodegradable encapsulation material on this sensor is studied.