An efficient optical-electrochemical dual probe for highly sensitive recognition of dopamine based on terbium complex functionalized reduced graphene oxide†
Abstract
A novel organic–inorganic hybrid sensor based on diethylenetriaminepentaacetic acid (DTPA) modified reduced graphene oxide (RGO–DTPA) chelated with terbium ions allows detection of dopamine (DA) through an emission enhancement effect. Its luminescence, peaking at 545 nm, has been improved by a factor of 25 in the presence of DA (detection limit = 80 nM). In addition, this covalently bonded terbium complex functionalized reduced graphene oxide (RGO–DTPA–Tb) can be successfully assembled on a glassy carbon electrode. The assay performed through differential pulse voltammetry (DPV) yielded obvious peak separation between DA and excessive amounts of the interfering ascorbic acid (AA).