Serine is an amino acid that exists in mammalian tissues. Researchers suggest that low level of Serine may contribute to neuropsychiatric disorders. The objective of this research is to develop a new disposable reduced Graphene oxide- Congo red-molecular imprinted polymer (rGO-CR-MIP) sensor using organic thin film transistor {OTFT) on polyethylene terephthalate (PET) flexible substrate for serine detection. The rGO-CRMIP, as sensing material, was polymerized on interdigitated electrodes of OTFT. In this thesis, a molecular modeling was developed to study the intermolecular interactions in the pre-polymerization mixture of MIP. Using HYPERChem software the optimum binding energy was obtained at a I :5 ratio. In order to confirm the results of molecular modeling, six different ratios MIP were synthesized for binding study. From the study, it is shown that I :5 ratio have the highest binding with the adsorption capacity of 23.63
mg/g. The rGO-CR was introduced in order to improve conductivity of MIP. The conductivity of rGO-CR-MIP differs significantly due to the intrinsic characteristic of rGO-CR. The resulting rGO-CR-MJP exhibit bulk conductivity of 3.1 Ox I o·3 sm·' at 0.4 % (w/v) rGO-CR. The influences of the temperature of substrate temperature (Tsub) on electrical performance of TIPS-Pentacene OTFT have been investigated. TlPSPentacene deposited at substrate temperature Tsub, 100 °C exhibited a better performance. With the drain current Io, 0.07135 A. By increasing Tsub temperature will increase grain size and carrier mobility of transistors. The performance of rGO-CR-MIP OTFT sensor exhibited a fast response with a response time of 14 seconds. During the
selectivity test the 10 is much higher than valine and isoluecine, implying a highly selective recognition of rGO-CR-MIP OTFT sensor to Serine. From the sensitivity analysis, the sensor exhibited a limit of detection at 20 ppm.The sensor exhibited a high sensitivity and good selectivity for Serine and it was successfully applied to its detection.
