Development of a biomimetic sensor through molecular imprinting

Molecular imprinting is a technique for creating synthetic receptor sites in a polymer. In this research, a molecularly imprinted polymer (MIP) biomimetic sensor was formed for theophylline using a copolymer of two monomers, methacrylic acid and ethylene glycol dimethacrylate. The presence of theophylline in the biomimetic sensor was measured using cyclic voltammetry, specifically, the corresponding peak currents on the voltammograms. The peak currents of the MIP sensor in the presence and absence of theophylline were compared to the blank sensor (non-imprinted polymer).; In the initial measurements, the peak current for the MIP sensor on indium tin oxide (ITO) increased by a factor of 5.3 upon addition of theophylline compared to the blank non-imprinted MIP. The ratio of peak currents increased by a factor of 7.5 for the MIP sensor on silicon compared to the blank. The sensitivity of the MIP on ITO was between 2--4 mM theophylline. The concentration of theophylline that resulted in the best signal was 3 mM. The MIP sensor showed no cross reactivity to caffeine, which has a similar chemical structure. This research will provide the foundation for future work in biomimetic sensors by developing durable sensors with longer shelf lives when exposed to rugged and harsh environments.