Power generation and autonomous glucose detection with an integrated array of abiotic fuel cells on a printed circuit board

Wearable technologies can enable effective management of life-threatening diseases. In such systems, miniaturisation leads to minimally invasive and lightweight devices that, whilst ensuring safety, allow patients to perform their everyday activities freely. By generating direct and continuous energy from physiological fluids at body temperature, glucose fuel cells (GFCs) provide an attractive and easy-to-miniaturise power source alternative to lithium batteries. In this context, we explore for the first time the use of printed circuit boards (PCBs) for the development of integrated arrays of abiotic GFCs and successfully demonstrate their operation at physiological concentrations of glucose, both in a phosphate buffer and in synthetic interstitial fluid. Each GFC consists of a porous gold anode and a Pt/Au cathode in a single layer, and generates a maximum power of 14.3 μW cm⁻² (in 6 mM of glucose), with a linear response to glucose within a concentration range that includes hypo- and hyper-glycaemic values. We also demonstrate linear power output scale-up by electrically connecting in parallel four GFCs on PCB. Considering the simplicity of the system architecture and the ease of integration provided by PCBs, our pioneering work paves the way for exciting opportunities in the field of self-powered wearable diagnostics.