Biodegradable S-nitrosothiol tethered multiblock polymer for nitric oxide delivery

A biodegradable multiblock polymer containing the S-nitrosothiol moiety was synthesized via a 4 step process using non-aqueous reaction conditions. The structural and morphological properties of the material were characterized via (1)H NMR, GPC, DSC, TGA, and SAXS. The nitric oxide (NO) storage capacity of the polymer was found to be 0.42 +/- 0.01 mmol NO per g polymer using UV spectroscopy, and real-time chemiluminescence measurements demonstrated a controlled and extended NO release profile. The degradation rate of the material was the most rapid during the first week followed by a slower linear release rate. Preliminary biocompatibility testing of the material using ISO protocols indicated no cell lysis in vitro. Taken together, this material has the requisite properties to control initial biological responses and the longevity to provide longer term mechanical support.