Label-free ultrasensitive electrochemical dopamine sensor fabrication using a low-cost pencil graphite electrode.

A novel and label-free electrochemical sensing strategy was explored for designing the ultra-low-level dopamine sensor based on a low-cost pencil graphite electrode (PGE). Electrochemical measurements of the PG electrode towards dopamine detection were performed using the anodic sweeping voltammetry (ASV) technique with optimized deposition voltage and time. With a sensitivity of 0.022 μA nM−1 cm−2, the PG electrode demonstrated sufficient potential for highly selective detection of dopamine down to 26.5 nM concentration in the presence of other interfering bioanalytes. [Display omitted] • Pencil graphite electrode (PGE) shows excellent low-level detection ability of Dopamine. • PGE offers very low-cost sensing strategy for Dopamine sensor. • Bare PGE can detect dopamine down to 26.5 nM. • PGE shows excellent specific selectivity of the Dopamine in the presence of ascorbic and uric acids. • PGE based Dopamine sensor shows 74 % reusibility. [ABSTRACT FROM AUTHOR]