Extending the pH Stability of Poly(2‐Oxazoline)/Poly(Acrylic Acid) Double‐Network Hydrogels by Including Acrylamide as Comonomer
Year: 2025
Type: article
Abstract: ABSTRACT Double‐network hydrogels (DNHs) have outstanding mechanical properties, making them suitable for biomedical applications, such as artificial cartilage. One example of a biocompatible DNH with a mechanical behavior that exactly matches that of natural cartilage is based on poly(2‐methyl‐2‐oxazoline) (PMOx) as primary and poly(acrylic acid) (PAA) as a secondary network, which is stabilized by hydrogen bonds formed between the protonated PAA and the PMOx carbonyl groups. This DNH is shifting the deprotonation of PAA to a pH of 7.6, which makes it applicable in natural tissue. However, implanted hydrogels often encounter varying pH conditions within different tissues or in response to inflammation and infection. Thus, a further shift of the pKa toward more basic conditions is necessary. In this study, the secondary network in the PMOx‐based DNHs was systematically varied by copolymerizing acrylic acid (AA) and acryl amide (AAm) and the mechanical properties were investigated in PBS buffer with varying pH. A ratio of 10 wt.% AAm in the secondary network resulted in a PMOx/P(AA 90 ‐co‐AAm 10 ) DNH that is not deprotonated even at pH 9 and does not change its dimensions or its cartilage‐like mechanical properties up to this pH.
Institution: TU Dortmund University
Language: English
Subfield: Molecular Medicine
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,550
OpenAlex ID: W4416055650