A sensitive porphyrin/reduced graphene oxide electrode for simultaneous detection of guanine and adenine

In this study, we prepared the porphyrin/reduced graphene oxide (porphyrin/RGO) nanocomposite which combined the excellent electrical conductivity and high specific surface area of RGO and the catalytic effect on the oxidation of guanine and adenine of porphyrin for simultaneous detection of guanine and adenine. Since the nanocomposite had remarkable synergistic effect between porphyrin and RGO, the modified glassy carbon electrode (GCE) exhibited excellent electrochemical catalytic activities and high sensitivity toward the detection of guanine and adenine. The nanocomposite was successfully applied to simultaneous quantitative detection of guanine and adenine with a linear range covering 0.05–150 and 0.2–100 μM, respectively, and the detection limits (LOD) ( S / N  = 3) were estimated to be 0.016 μM for guanine and 0.06 μM for adenine. The porphyrin/RGO/GCE was applied for simultaneous detection of trace amounts of guanine and adenine in hydrochloric calf thymus DNA. Moreover, the porphyrin/RGO/GCE was simply fabricated and displayed good reproducibility.