The BioDomes were composed of a soft silicon insert that contained silk hydrogels as a controlled-release substrate and drug carrier. The fabrication of the device has been reported elsewhere (34 (link)). Briefly, the outer cylindrical silicon sleeve (20-mm H × 18-mm D) was fabricated by casting silicon elastomer (Dragon skin 10, Smooth-on, Macungie, PA) against a 3D-printed mold, which was designed using CAD software (SolidWorks, Waltham, MA, USA) and printed using a Formlabs 3D printer (Somerville, MA, USA).