Development of a xurographically fabricated miniaturized low-cost, high-performance microbial fuel cell and its application for sensing biological oxygen demand

•First application of xurographic fabrication technology to construct micro-MFC.•The cost of fabricating the sensor is lower than 0.5 USD.•The response time of the BOD sensor could be as short as 1.1 min.•The sensor can cover a wide range of BOD between 20−490 mg/L.