An electrochemical platform for guanosine-5’-monophosphate detection using gold doped polypyrrole nanocomposite embedded on graphitic carbon nitride

In this study, an electrochemical platform based on a novel ternary nanocomposite of advantageously united gold nanoparticles , polypyrrole and graphitic carbon nitride (Au-PPy@ g- C 3 N 4 ) for detection of guanosine-5’-monophosphate (GMP) was designed. Owing to the π-π stacking interaction between the ring structures of the nucleobases in GMP and the hexagonal cells original from g -C 3 N 4 in Au-PPy@ g- C 3 N 4 , the irreversible oxidation of GMP occurred with the potential of 1.08 V (vs. SCE) in phosphate buffer solution (PBS). Under the optimized conditions, the peak currents were linear with the concentration of GMP ranging from 0.05 to 200 μg•mL −1 with a detection limit of 0.028 μg•mL −1 (S/N=3). Meanwhile, the Au-PPy@ g- C 3 N 4 /APTES/GCE sensor exhibited good stability, high reproducibility and acceptable anti-interference ability. Importantly, the results of the detection of GMP with the proposed sensor were well consistent with the data determined by high performance liquid chromatography (HPLC), indicating a promising platform for evaluation of soup quality.