A carbon paste electrode (CPE) modified with (9, 10-dihydro-9, 10-ethanoanthracene-11, 12-dicarboximido)-4-ethylbenzene-1, 2-diol (DEDE) and NiO/CNTs nanocomposite was used for the sensitive
voltammetric determination of cysteamine (CA), nicotinamide adenine dinucleotide (NADH) and folic
acid (FA) for the first time. The synthesized materials were characterized with different methods such as
XRD, cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and square wave voltammetry
(SWV). The modified electrode exhibited a potent and persistent electron mediating behavior followed
by well-separated oxidation peaks of CA, NADH and FA. The peak currents were linearly dependent on
CA, NADH and FA concentrations using square wave voltammetry (SWV) method in the ranges of
0.01–250, 1.0–500, and 3.0–550 mmol L−1
, with detection limits of 0.007, 0.6, and 0.9 mmol L−1
, respectively. The modified electrode was used for the determination of CA, NADH and FA in biological and
pharmaceutical samples.