2.3. Electrochemical measurements
Cyclic voltammetry measurements were made in an unstirred
0.10M phosphate buffer (pH 7.0). All potentials were measured
and reported versus Ag/AgCl. After the preparation of the
modified electrode (i.e., DSNPs-GCE), it was rinsed with
double-distilled water and placed in 0.10M phosphate buffer
(pH 7.0). Cyclic voltammograms and linear sweep voltammetry
were performed. Differential pulse voltammetry (DPV) was
measured in 10.0 mL 0.10M phosphate buffer (pH 7.0) containing
different concentrations of NA. The current of the
voltammograms versus the NA concentrations were then
depicted, and the linear ranges were determined