A sensitive and selective graphene/cobalt tetrasulfonated phthalocyanine sensor for detection of dopamine

Electrochemical dopamine-sensing surfaces were fabricated by deposition of graphene sheets modified with cobalt tetrasulfonated phthalocyanine on glassy carbon electrodes (CoTSPc/Gr-GC) using differential pulse amperometry. Differential pulse stripping voltammetry was used to detect dopamine (DA) and the influence of pH value, scan rate, accumulation potential and time as well as dopamine concentration on the performance of CoTSPc/Gr-GC electrodes was investigated. The modified electrodes were successfully used as sensors for the selective and high sensitive determination of DA in presence of high concentrations of ascorbic acid (AA) and uric acid (UA) with a detection limit of 0.87 nM over the dynamic linear range of 20 nM to 220 nM.