A protocol to execute a lab-on-chip platform for simultaneous culture and electrochemical detection of bacteria.

Here, we present a protocol for a miniaturized microfluidic device that enables quantitative tracking of bacterial growth. We describe steps for fabricating a screen-printed electrode, a laser-induced graphene heater, and a microfluidic device with its integrations. We then detail the electrochemical detection of bacteria using a microfluidic fuel cell. The laser-induced graphene heater provides the temperature for the bacterial culture, and metabolic activity is recognized using a bacterial fuel cell. Please see Srikanth et al.1 for comprehensive information on the application and execution of this protocol.

A facile technique to develop conductive paper based bioelectrodes for microbial fuel cell applications.

Electronic devices with multifunctional capabilities is forever an attractive area with diverse scope including towards developing solutions to sustainable energy technology. Microbial biofuel cells (MiBFCs) are one such sustainable energy technology based electronic device which can not only harvest energy, but can perform biosensing leading to bioremediation. However, low energy yield, costly fabrication procedures and bulky devices are some of the limitations of such MiBFCs. In this work, for the first time a simple vacuum filtration fabrication technique is used for making thin and conductive electrodes with homogeneous CNT solution for MiBFC application. The fully paper-based MiBFC is integrated into a compact micro device with 3D printed components which adds novelty to the work. The MiBFC is capable of maintaining a stable open circuit voltage of 410 mV for more than 1 h and can deliver a maximum power density of 192 µW/cm2 which is reasonably high for such paper-based MiBFCs operating with micro-volume of substrate. This device will help in developing more freestanding power sources for instant diagnostics and data transfer.