Thin Layer Chromatography for the Smartphone Biosensor

The research project makes use of thin layer chromatography (TLC) to identify and tag different mixtures, molecules or compositions and also their concentration within any given sample. TLC plates are covered with an adsorbent, usually silica or alumina, but any other material can also be used depending upon the molecules we are trying to detect. The solvent mixture/molecule is placed at the very bottom of the plate which rises up due to the adsorbent as a result of capillary action. We then picture and analyze the spots on the plate under UV light to classify the mixture/molecule and also come up with useful statistics such as concentration. An example is when two or more samples of the same mixture are used and their distance from the bottom of the plate and their size and positions are measured and analyzed to find their respective concentrations and/or to check counterfeit samples. Being a part of the smartphone biosensor project, a cradle is created that is customized for each phone we are trying to use to detect these molecules in the solvent mixture. The cradle is customized to fit the smartphone in question, a UV light, and has a crevice to fit in the TLC plate for analysis. This picture taken from the smartphone is then fed into the computer and analyzed using software and settings dependent upon the kind of mixture/molecule. The results so far have been very encouraging and we are trying to increase the number of compatible phones by designing new and improved cradles. We encountered some problems regarding the minimum concentration that the smartphone biosensors can detect but we are actively working to increase the range of detection.U of I OnlyUndergraduate senior thesis not recommended for open acces