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Running an MFC Experiment

This page is intended as a comprehensive guide to completing a microbial fuel cell setup and running an experiment from start to finish.

Creating a Testing Environment

Begin 1-2 weeks prior to experiment

Constructing Fuel Cell Components

Materials (per fuel cell)

  • 4" Polycarbonate Square Tube, 2" Outer Diameter
  • 6" x 6" Polycarbonate Sheet, 1/4" Thick
  • 4 Steel Fully Threaded Stud, 1/4"-20 Thread, 6" Length
  • 8 Zinc Alloy Wing Flange Nut, 1/4"-20 Screw Size, 1" Wing Spread
  • 1" x 1" Nafion® membrane, 0.180mm thick
  • 1" x 1" Carbon felt, 0.25" thick
  • 1.5" x 1.5" E-TEK ELAT™ GDE (platinum on carbon)
  • 2' Titanium Grade 2 Wire .046" Diameter
  • Teflon Tape, 1/4" Width
  • 5" x 2.5" Silicone Sheet
  • Silicone Glue
  • Spiral Point Tap 1/4"-28
  • 8 Plastic Luer Lock Coupling Nylon, Female to Male Thread, 1/4"-28


  1. Mill Polycarbonate
    • Cut polycarbonate sheet into 4 equal 3" x 3" pieces
    • Drill four 3/8" holes through each piece, 1 per corner, indented 5mm from both sides


    • Cut polycarbonate tube into two equal 2" halves
    • Drill four 1/4" holes through each half in configuration shown

Drilled tube.jpg

    • Tap each hole with 1/4" -28 spiral tap
  1. Glue Chambers (repeat for each half)
    • Center tube on endplate by marking plate with 'X' from corner to corner
    • Squirt 2mm thick line of silicone on edge of tube (edge furthest from holes)
    • Press tube firmly against marked location on endplate
    • Quickly spread excess silicone along edge
    • Let stand 24h to harden

Glued half.jpg

  1. Construct Gaskets
    • Cut silicone sheet into two equal 2.25" x 2.25" pieces
    • Cut out centered inner squares in each piece, 1.75" x 1.75"
    • Using inner squares, cut two 'O' rings, inner diameter 1/4", outer diameter 1/2"


  1. Construct Electrodes
    • Cut titanium wire into one 8" piece and one 16" piece
    • Using pliers, shape anode and cathode as shown


    • Spear carbon felt with tip of anode titanium wire and wedge into frame
    • Weave platinum carbon cloth through cathode titanium wire


  1. Seal Injection Ports
    • Wrap threads of all eight Luer Lock screws with 1' of teflon tape in opposite direction of screwing
    • Screw Luer Locks into all tapped holes in both chambers

Fin chamber.jpg

Setup of Measurement Device


  • Keithley 2700 Digital Multimeter
  • Keithley 7700 Multiplexer
  • Small Breadboard
  • Supply of insulted thin copper wire
  • 470 Ohm resistors (one/fuel cell)


  1. Wire Multiplexer
    • Open multiplexer, note channels
    • Cut two wire 18" wire leads per fuel cell
    • Strip ends, place one wire in each screw terminal, screw tight
    • Tape paired wires (two are attached to each channel) near non-attached ends and label
    • Clamp wire bundles near back of device with provided plastic latch clamps
    • Close Multiplexer and slide into 2700 DMM
  1. Create Resistor Array
    • Connect resistors across middle of breadboard (one per fuel cell)
    • Connect leads from multiplexer across resistors (one pair across each resistor)

Controlling the DMM with LabVIEW™

  1. Initialize Multimeter
    • Attach 2700 to COM1 port of desktop computer w/ LabVIEW™
    • Download our LabVIEW™ source code

Experiment Preparation

Begin 1 day prior to experiment

Assembling Chambers

Solutions Prep

Chamber media

  • 5.844 g/L 100mM NaCl
  • 15.1185 g/L 50mM PIPES (hydrogen)

7.0 pH

Phosphate buffer

  • 2.918 g/L Monosodium phosphate, monohydrate
  • 4.095 g/L Disodium phosphate, anhydrous
  • 5.844 g/L 100mM NaCl

7.0 pH

Gas Tubing Assembly

Growing Strains


Begin 2 hours prior to experiment


Fuel Cells


Clean Up