title: On the biodegradability of polyethylene glycol, polypeptoids and poly(2-oxazoline)s.
abstract: Despite being the gold standard of hydrophilic biomaterials and well known sensitivity of polyethylene glycol (PEG) against oxidative degradation, very little information on the decomposition of PEG under biological oxidative stress can be found in the literature. Poly(2-oxazoline)s (POx) and polypeptoids (POI), two pseudo-polypeptides, have attracted some attention for the use as biomaterials and alternative to PEG with an altered stability against oxidative degradation. All three polymer families are supposedly non-biodegradable, which could be seen as one of their main disadvantages. Here, we present evidence that PEG, POx and POI are degradable by oxidative degradation under biologically relevant conditions. Transition metal catalysed generation of reactive oxygen species (ROS) leads to a pronounced time and concentration dependent degradation of all polymers investigated. While we do not envision oxidative degradation to be of relevance in the short-term usage of these polymers, mid- and long-term biodegradability in vivo appears feasible. Moreover, influence in ROS mediated signalling cascades may be one mechanism how synthetic polymers influence complex cellular processes.
authors.affiliation: Functional Polymer Materials, Chair for Chemical Technology of Materials Synthesis, University Würzburg, Röntgenring 11, 97070 Würzburg, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Ulbricht
authors.affiliation: Professur für Makromolekulare Chemie, Department Chemie, Technische Universität Dresden, Mommsenstr. 4, 01069 Dresden, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Jordan
authors.affiliation: Functional Polymer Materials, Chair for Chemical Technology of Materials Synthesis, University Würzburg, Röntgenring 11, 97070 Würzburg, Germany. Electronic address: robert.luxenhofer@uni-wuerzburg.de.
authors.forename: Robert
authors.initials: R
authors.lastname: Luxenhofer
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D010080:Oxazoles / Q000737:chemistry*; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry; D034444:Peptoids / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D017382:Reactive Oxygen Species / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D010080:Oxazoles; D010455:Peptides; D034444:Peptoids; D017382:Reactive Oxygen Species; C577913:poly(2-oxazoline); D011092:Polyethylene Glycols; D006861:Hydrogen Peroxide
keywords: Biomaterials; Gel permeation chromatography; Hydrogen peroxide; Oxidative degradation; Reactive oxygen species