Susan Lees
White House High School
Chemistry

Dr. G. Kane Jennings, Organic Films Lab

My lab experience was based on a plant’s ability to transfer the energy of sunlight into electrical impulses through the photosynthetic processes.  We extracted photosystem I (p-700 sites) from spinach leaves.  The extraction process is a three day procedure.  We de-veined a bag of baby spinach leaves and prepared a variety of solutions and buffers to be used in the course of the extraction. (Chemistry skills are a must!) We then set up a column to filter the prepared spinach extract trapping the p-700 sites that we had released.  Once the p-700 sites were trapped, we used an elution buffer to suspend the concentrated sites.  Once collected, we stored the p-700 sites in a -80º C freezer to be used over next few months by the research team.  We then tested our extraction to make sure that we had captured the p-700 sites.  We used IR spectroscopy to prove the sites were present in our extraction.  We then prepared self-assembled monolayers (SAMS) of different bases to attach the p-700 sites from the extraction.  I was responsible for the covalent attachments and the stability studies of the covalent attachments.  The SAMS are made of a silicon wafer with a chromium base and a gold layer.  The bases attach to the gold layer and the covalent bonds attach to the base.  This provides a bed on which the p-700 sites attach.  If attached and viable, these sites provide an electron transfer station to move electric impulses from the gold, through the p-700 molecules.  The molecules then serve as a nano-battery supplying energy.  We tested our SAMS layers for stability by sonification and then used electrochemistry to see if our p-700 sites were providing any amperage.  We had success and showed amperage being produced in the presence of light, with no amperage in the absence of light.  We had trapped viable p-700 sites and used them to produce energy on a non-living surface.

I plan to use my greatly enhanced knowledge to help me to teach covalent bonding in my chemistry class.  The curriculum I have designed is based on a covalent attachments normal repulsion of water. I plan to use this to emphasize polar and non-polar covalencies as a real-life application. I can also impress on the students the alternate fuel source research that is being done to help our world in general.