Poly(glycerol sebacate) (PGS) is an elastomer used widely in tissue engineering studies due to good biocompatibility. Hereby, we report tyramine-functionalized PGS called PGS-TA. Tyramine adds a stronger physical bonding capability to PGS-TA. Tensile tests showed that the softness and toughness of the material were similar to those of PGS. However, PGS-TA demonstrated a 16-fold increase of elastic deformations compared to PGS processed under identical conditions. The in vitro studies demonstrated that the viability and metabolic activity of baboon smooth muscle cells were the same as those on tissue culture polystyrene. Porous subcutaneous implants of PGS-TA substantially degraded in vivo over two weeks, showing good biodegradability and biocompatibility. We expect PGS-TA to be useful for applications in tissues and organs that are subjected to large reversible mechanical deformations.

Strategies that can reduce harmful side effects of potent immunomodulatory drugs are in high demand to facilitate clinical translation of the newest generation of immunotherapy. Indeed, uncontrolled triggering of the immune system can lead to life-threatening cascade reactions such as e.g. cytokine storm. In particular, drug formulations that combine simplicity and degradability are of formidable relevance. Imidazoquinolines are an excellent example of such small molecule immunomodulatory drugs that exhibit in unformulated form a highly undesirable pharmacokinetic profile. Imidazoquinolines are potent inducers of type I interferons that are of great interest in the context of anti-cancer and anti-viral therapy through triggering of Toll like receptors 7 and 8. In this paper we aimed to alter the pharmacokinetic profile of imidazoquinolines using a simple, yet efficient, strategy that holds high potential for clinical translation. Hereto, we conjugated an imidazoquinoline to the backbone of poly(aspartate) and further formulated this into a degradable coacervate through complex coacervation with a non-toxic degradable polycation. The intrinsic TLR activity of the imidazoquinoline was well preserved and our formulation strategy offered spatial control over its biological activity in vivo.