An anticoagulant supercapacitor for implantable applications

With the rapid advancement of implantable electronic medical devices, implantable supercapacitors have emerged as popular energy storage devices. However, supercapacitors inevitably come into direct contact with blood when implanted, potentially causing adverse clinical reactions such as coagulation and thrombosis, impairing the performance of implanted energy storage devices, and posing a serious threat to human health. Therefore, this work aims to design an anticoagulant supercapacitor by heparin doped poly(3, 4-ethylenedioxythiophene) (PEDOT) for possible applications in implantable bioelectronics. Heparin (Hep), the as-known anticoagulant macromolecule acts as the counterion for PEDOT doping to enhance its conductivity, and the bioelectrode material PEDOT: Hep with anticoagulant activity is synthesized via chemical oxidation polymerization. Concurrently, the anticoagulant supercapacitor is constructed through in-situ polymerization, where PEDOT: Hep and bacterial cellulose as electrode material and electrolyte layer, respectively. Owing to the incorporation of heparin, the supercapacitor exhibits high hemocompatibility with hemolysis rate <5 %, good anticoagulant performance with coagulation time of 63.4 s, reasonable cycle stability with capacitance retention rate of 76.24 % after 20, 000 cycles, and supplies power for implanted heart rate sensors in female mice. This work provides a platform for implantable electronics to achieve anticoagulant activity in vivo. Implantable supercapacitors are promising for the use as energy supply devices within the body, but their utility is hindered by coagulation and thrombosis. Here, the authors report an implantable supercapacitor that exhibits good anticoagulant properties and cycling stability.