S-Nitrosothiol-modified hyperbranched polyesters†
Hyperbranched polyesters with a range of exterior thiol modifications were synthesized through a Michael addition thiol–ene reaction. S-Nitrosothiol nitric oxide (NO) donors were subsequently introduced onto the scaffolds to yield NO-releasing polyesters with total NO storage of ∼2.0 µmol mg−1. Multiple decomposition pathways (i.e., use of light, copper ions, and heat) triggered S-nitrosothiol NO donor breakdown and NO release under physiological conditions (37 °C, pH 7.4). The NO-releasing polyesters were characterized as a function of chemical modification and scaffold size or generation. The approaches described herein expand the scope of biodegradable NO-releasing materials with large NO payloads.