Zwitterionic Porous Conjugated Polymers as a Versatile Platform for Antibiofouling Implantable Bioelectronics

Here, we describe the design, synthesis, and evaluation of two kinds of multifunctional zwitterionic linear poly(carboxybetaine thiophene) (PCBTh) and porous poly-(carboxybetaine thiophene-co-9,9'-bifluoreneylidene) (PCBTh-coBF) polymers, which can be facilely synthesized using Yamamoto and Suzuki polycondensation, respectively. The integrations of zwitterionic polymer-based biomaterials that consist of conjugated polymer backbones, multifunctional zwitterionic side chains, and distorted units are designed and studied to address a key challenge of conjugated polymers in biomedical applications: biofouling phenomena that eventually lead to the failure and reduced lifetime of bioelectronics in the body. The introduction of a twisting unit into the polymer backbone allows us to tune the porosity, morphology, optical properties, and efficiency of antibiofouling features of resulting polymers. The PCBTh-coBF coated surface exhibits good conductivity, stability, hydrophilicity, and antibiofouling properties against protein adsorption, cell growth, and bacteria attachment, which may be useful for chronic in vivo bioelectronics applications by minimizing the foreign body response.