LAUSR

Currently available bioelectronic devices consume too much power to be continuously operated on rechargeable batteries, and are often powered wirelessly, with attendant issues regarding reliability, convenience and mobility. Thus, the availability of a robust, self-sufficient, implantable electrical power generator that works under physiological conditions would be transformative for many applications, from driving bioelectronic implants and prostheses to programing cellular behaviour and patients' metabolism. Here, capitalizing on a new copper-containing, conductively tuned three-dimensional carbon nanotube composite, we designed an implantable blood-glucose-powered metabolic fuel cell that continuously monitors blood-glucose levels, converts excess glucose into electrical power during hyperglycemia and produces sufficient energy (0.7 mW cm-2 , 0.9 V, 50 mM glucose) to drive opto- and electro-genetic regulation of vesicular insulin release from engineered beta cells. We show that this integration of blood-glucose monitoring with elimination of excessive blood glucose by combined electro-metabolic conversion and insulin-release-mediated cellular consumption enables the metabolic fuel cell to restore blood-glucose homeostasis in an automatic, self-sufficient and closed-loop manner in an experimental model of type-1 diabetes. This article is protected by copyright. All rights reserved.