LAUSR

In this study, non-enzymatic and enzymatic tyramine sensors were prepared by using P[5]A as a surface modification material. P[5]A, which belongs to the group of ionic liquids, enables the development of a biocompatible and stable electroactive electrode surface. In the modification process, P[5]A dispersed in gelatin solution was dropped on a glassy carbon electrode (GCE). In the preparation of enzymatic sensor, tyrosinase (TYR) was immobilized by used glutaraldehyde as a cross-linker on P[5]A modified GCE surface. Surface morphology and electrochemical behavior of P[5]A modified GCE was investigated by scanning electron microscope (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Experimental conditions such as pH, working potential and P[5]A amount were optimized as GCE/Gel/P[5]A and GCE/Gel/P[5]A/TYR. Under optimum experimental conditions, linear working ranges of GCE/Gel/P[5]A and GCE/Gel/P[5]A/TYR was $8.0\times 10^{-8} - 1.5\times 10^{-6}$ M with LOD of $4.0\times 10^{-8}$ M and $1.6\times 10^{-6} - 4.2\times 10^{-5}\text{M}$ with LOD of $5.0\times 10^{-7}$ M, respectively. These sensors showed a lower detection limit, high selectivity and good repeatability for tyramine. Analytical applicability of non-enzymatic and enzymatic sensor was examined by tyramine analysis and recovery studies in the sauerkraut sample.