Musings on Thomas Edison and Auto Paint Analysis

Step three of my summer research plan is to identify a characteristic spectrum for each manufacturer auto paint sample. We have two different auto paints samples one from Honda and the other from Toyota. To begin the initial testing I performed a normal Raman scan without silver nanoparticles of each paint. One was found to be normal Raman active and the other was not. Normal Raman active means that without silver nanoparticles I was able to identify a characteristic spectrum. After the normal Raman scans, I performed a simple SERS test on each paint. A simple SERS test is done by only applying silver nanoparticles to the paint sample. This yielded some results but not as distinctive of a characteristic spectrum as I would like. In order to get a more characteristic spectrum, I started to develop an extraction method. The extraction method, in theory, would coax out the chromophore or pigment into the solvent making it easier to see a characteristic spectrum with SERS. However, this has not been the case. Auto paint matrixes are extremely complex with multiple additives, binders, resin, and pigments. Due to their complexity I have not been able to fully extract the chromophore, but I have been able to slowly breaking down the matrix with some simple solvents. This has allowed me to see some characteristic spectrum for the two paints, but again not to the distinctiveness that we would like. Research is a complicated process. I often like to take comfort in Thomas Edison’s wise words that he said when he was inventing the light bulb: “I have not failed. I’ve just found 10,000 ways that won’t work.” I have not failed either. I’ve just found five ways that won’t extract a paint pigment.