1. Biofuel Cells Tila Hidalgo, Alief ISD Chris Skinner, El Campo ISD Zhilei Chen, PhD, Artie McFerrin Department of Chemical Engineering Texas A&M University

2. Chemical Engineering Working with Dongli Guan, PhD Electrochemistry using reagents available in and compatible to biological systems.

3. Biofuel Cells Redox Reactions- transfer of electrons Fuel Cell- parts of the reaction are split into the anode and cathode so that electrons are forced to travel. Reagents such as oxygen and glucose produce products that are not harmful such as water while generating free electrons. Zebda et al 2011

4. The Research Question How can we make a biofuel cell generate sufficient power and longevity?

5. Why? Useful in various biomedical implants. http://whoinvented.org/wp- content/uploads/2010/11/pacemaker1.jpg

6. The Research Objective To improve power and longevity of the fuel cell. Current Issues Not a lot of power generated Poor connections Loss of enzyme from the fuel cell

7. Engineering a new protein Recombinant DNA is used to create an enzyme that will both catalyze the needed reaction and attach to the gel cathode and anode. The hope is that this will address the issues with the fuel cell.

8. Plasmids Small circular pieces of bacterial DNA. http://www.biologie.uni-regensburg.de/Experimentierlabor/Experimente/Plasmid%20Isolierung/plasmid2.gif

9. Recombinant DNA DNA for the desired protein is identified, and cut out with restriction enzymes. Plasmid DNA is cut with the same restriction enzymes. The pieces are put together with an enzyme called ligase to create a new plasmid. http://explorebio.wikispaces.com/file/view/sticky_ends.jpg/204841238/sticky_ends.jpg

10. http://biologyjunction.com/plasmid.gif

11. Transformation Newly engineered plasmid is then put into E. coli through a process called transformation. Transformed E. coli is then grown and induced to make the newly engineered enzyme. The protein is then harvested, purified and tested in the biofuel cell.

12. Protein Purification Once harvested, the proteins must be purified, or isolated During the engineering of the protein, it was "tagged" to make isolation easier The solution containing the protein is poured through a filter system.

13. Purification continued The protein is eluted from the filter using a buffer that has a higher affinity for the molecule The collected protein solution undergoes electrophoresis to demonstrate its purity

14. Construct a Fuel Cell Mix enzyme with Multi-walled carbon nanotubes (MWNT’s) Fix enzyme to electrodes Argarose + MWNT + enzyme

15. Adhere to electrode

16. Measure Voltage

18. Summary Biofuel cells have great potential for real world application. Addressing issues with current models of biofuel cells by engineering proteins will provide low cost, high yield, green technology for use in living organisms.

19. Acknowledgements TAMU E3 program National Science Foundation Nuclear Power Institute Dr. Chen and Dr. Guan

20. Citation Zebda, Abdelkader, Gondran, Chantal, Le Goff, Alan, Holziger, Michael, Cinquin, Phlippe, Consiner, Serge. Mediatorless high-power glucose biofuel cells based on compressed carbon nanotube- enzyme electrodes. Nature Communications. 2011. 10: 1038.