Synthesis and Characterization of PGD Prepolymer

PGD prepolymer was synthesized following the method described by Solorio et al. [27 (link)]. Briefly, PGD prepolymer was synthesized by mixing glycerol and dodecanedioic acid with a 1:1 molar ratio in a 120 °C flask under nitrogen and stirring conditions for 24 h, followed by vacuum environment at 120 °C for 24 h. The viscous prepolymer was then cast onto InkJet Plus microscope slides (Fisherbrand, Pittsburgh, PA, USA) or into 3 mL glass vials (Supelco, Bellefonte, PA, USA). The PGD prepolymer spontaneously spread to a film on the microscope slides or created a flat surface on the bottom of glass vials, and was then cured at 130 °C for 48 h. A vacuum was pulled and maintained at 90 mTorrs for the duration of the curing process. All the PGD samples were soaked in the growth media for 2 days with three media changes to remove any possible cytotoxic PGD byproducts that could dissolve in the media.