One step electrosynthesis of polyacrylamide crosslinked by reduced graphene oxide and its application in the simultaneous determination of dopamine and uric acid

Polyacrylamide (PAM)/reduced graphene oxide (rGO) nanocomposite (PAM/rGO) with rGO nanosheets as cross-linkers were synthesized via electropolymerizing acrylamide in an aqueous suspension of GO containing sodium nitrate and potassium persulfate. The PAM/rGO was characterized with X-ray diffraction (XRD), Fourier transfer infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). XRD patterns of the PAM/rGO indicated that rGO was fully exfoliated into individual sheets in the polymer matrix. SEM study exhibits the highly uniform coverage of PAM/rGO membrane on the GCE and its fibrous nanostructure. The electrochemical characteristics of the PAM/rGO modified glassy carbon electrode (GCE) were investigated with cyclic voltammetry (CV), suggesting the extraordinary electrocatalytic effect of PAM/rGO/GCE towards the electro-oxidation of UA and DA. The PAM/rGO/GCE behaved linearly to DA and UA in the concentration range of 3 × 10−7 to 5 × 10−5 M and 1 × 10−6 to 5 × 10−5 M with a detection limit of 1 × 10−7 M and 5 × 10−7 M, respectively. The proposed method was successfully utilized for simultaneous determination of UA and DA in real samples.