Adjustable Degradation Properties and Biocompatibility of Amorphous and Functional Poly(ester-acrylate)-Based Materials

Abstract

Tuning the properties of materials toward a special application is crucial in the area of tissue engineering. The design of materials with predetermined degradation rates and controlled release of degradation products is therefore vital. Providing a material with various functional groups is one of the best ways to address this issue because alterations and modifications of the polymer backbone can be performed easily. Two different 2-methylene-1,3-dioxepane/glycidyl methacrylate-based (MDO/GMA) copolymers were synthesized with different feed ratios and immersed into a phosphate buffer solution at pH 7.4 and in deionized water at 37 °C for up to 133 days. After different time intervals, the molecular weight changes, mass loss, pH, and degradation products were determined. By increasing the amount of GMA functional groups in the material, the degradation rate and the amount of acidic degradation products released from the material were decreased. As a result, the composition of the copolymers greatly affected the degradation rate. A rapid release of acidic degradation products during the degradation process could be an important issue for biomedical applications because it might affect the biocompatibility of the material. The cytotoxicity of the materials was evaluated using a MTT assay. These tests indicated that none of the materials demonstrated any obvious cytotoxicity, and the materials could therefore be considered biocompatible.

Simulation of the Degradation of Cyclic Ketene Acetal and Vinyl‐Based Copolymers Synthesized via a Radical Process: Influence of the Reactivity Ratios on the Degradability Properties

“…Generally, the most common method to evaluate the copolymer degradation consists in following the decrease of the number‐average molecular weight ( M n ) with time. For example, Albertsson and co‐workers reported that MDO/glycidyl methacrylate (GMA) copolymers with a cumulative mole fraction of MDO units in the copolymer ( F MDO ) of 0.42 (synthesized with an initial MDO feed composition ( f MDO,0 ) of 0.65) lost 25% and 60% of their initial M n after 133 d of hydrolysis at 37 °C in PBS and deionized water, respectively. In the case of MDO/VA copolymers, Agarwal et al studied the hydrolytic degradation of copolymers with F MDO = 0.73 (synthesized with f MDO,0 = 0.76) in 5 wt% KOH methanol solution.…”

Thermally stable optically transparent copolymers of 2-methylene-1,3-dioxepane and N-phenyl maleimide with degradable ester linkages

“…They undergo radical and cationic ring-opening polymerization and provide polyesters, polyacetals or a combination of the two, depending on their structure and on the reaction conditions (12). 2-Methylene-1,3-dioxepane (MDO) is one of the very well studied CKAs in terms of homo-and copolymerization, with a large number of vinyl monomers such as methyl methacrylate (MMA) (13), styrene (14,15), vinyl acetate (16,17), propargyl acrylate (18), glycidyl methacrylate (GMA) (19), etc. Homopolymerization of MDO leads to an aliphatic biodegradable polyester with a polycaprolactone-like structure (20), whereas cationic polymerization of MDO provides mainly ring-retained acetal units in the polymer backbone (21).…”

Towards being genuinely smart: ‘isothermally-responsive’ polymers as versatile, programmable scaffolds for biologically-adaptable materials

“…[46][47][48][49][50][51] Poly(sulfides) provide an option for situations in which an oxidative response, such as those found in wound sites, is required 52, 53 and poly(disulfides) have potential application given the highly reducing environment found within cells compared to the systemic circulation. Poly(esters) or poly(amides), prepared by ring-opening polymerisation techniques, offer a route towards this where degradation by hydrolytic and/or enzymatic means is possible.…”