Comparison of accelerated and enzyme-associated real-time degradation of HMW PLLA and HMW P3HB films. (March 2022)

• Record Type: Journal Article
• Authors: Arbeiter, Daniela; Lebahn, Kerstin; Reske, Thomas; Senz, Volkmar; Eickner, Thomas; Schmitz, Klaus-Peter; Grabow, Niels; Oschatz, Stefan
• Is Part Of: Polymer testing. Volume 107(2022)
• Publication Date: 2022-03
• Subjects: Poly-l-lactide -- Poly-3-hydroxybutyrate -- Enzyme-associated degradation -- Accelerated degradation -- Molecular weight -- Crystallinity; Polymers -- Testing -- Periodicals; Polymères -- Tests -- Périodiques; 620.1920287
• DOI: 10.1016/j.polymertesting.2021.107471
• Languages: English
• ISSNs: 0142-9418

Abstract

Abstract: Designing laboratory-scale degradation experiments for polymer-based biomaterials is crucial for the development of safe and functional implants, in particular regarding high molecular weight polyesters. Within this work, we compared accelerated degradation of solvent cast HMW-PLLA and HMW-P3HB films at 55 °C (16 weeks) with enzyme-associated (proteinase K and lipases) real-time degradation at 37 °C (108 weeks). During real-time degradation, PLLA showed mass loss up to 83%, in contrast to accelerated conditions, where no changes occurred. Moreover, we observed wave-shape development of crystallinity for PLLA and PHB for both degradation conditions applied, whereby PLLA χ value nearly doubled to up to 75%. These results were used to develop a correlation model based on molecular weight decrease and were furthermore discussed in light of a detailed literature review. In summary, real-time in vitro studies could be adapted to accelerated protocols providing the same limiting conditions such as molecular weight and initial crystallinity are given. Highlights: Detailed literature overview on in vitro PLLA and P3HB degradation. Comparison of real-time and accelerated degradation of solvent cast HMW polyester films. Wave-shape development of crystallinity and molecular weight. Initial crystallinity has pronounced influence on degradation behavior. Proposal for a correlation model based on M w for accelerated and real-time degradation.