Preparation of polyneutral red on reduced graphene oxide modified electrodes and biosensor applications

In this study, polyneutral red (PNR) was prepared on the reduced graphene oxide modified surface printed electrodes and it was aimed to amperometric detection of dopamine (DA) as a biosensor application. Firstly, screen printed electrodes (SPCE) were modified with reduced graphene oxide (RGO). By the polymerizing of the neutral red on SPCE-RGOs with electropolymerization technique, SPCE-RGO-PNR electrodes were prepared. The optimum conditions of the electropolymerization of the PNR (the number of cycles and scan rate) were determined. The characterizations of the SPCE-RGO-PNR electrodes were performed electrochemically. Finally, the SPCE-RGO-PNR electrodes were modified with gold nanoparticles (AuNP). The SPCE-RGO-PNR-AuNP electrodes were used for the amperometric determination of DA as a biosensor application. The optimum working conditions (optimum pH, optimum working potential, linear working range) were determined in the amperometric determination of DA. The results of analytical characterizations, repeatability for 50 µM DA, sensitivity, the limit of detection and the limit of quantification and the linear range were found to be 2.14% (n = 10) as relative standard deviation (R.S.D.), 13,38 µA. mM-1; 0.17 µM and 0.57 µM and was 0.57 µM - 500 µM respectively. The developed DA sensor was used for DA determination in artificial blood serum samples. 2019, 71 pages KEYWORDS: Reduced graphene oxide, polyneutral red, dopamine, biosensor, screen-printed electrot