N-Graphene Paper Electrodes as Sustainable Electrochemical DNA Sensor

Abstract

The heteroatom doped graphene structure provides an effective platform for electrochemical sensing of deoxyribonucleic acid (DNA). In this work, we have doped heteroatoms such as nitrogen (N), phosphorus (P), and sulphur (S) to the graphene sheets obtained from biomass. The obtained heteroatom doped graphene was used to prepare electrodes on paper substrate and utilized for electrochemical sensing of calf thymus DNA. The electrochemical sensing response of the electrodes is confirmed from the oxidative peak (0.6 V to 0.8 V) related to guanine (G) sensing for all the electrodes. In addition, N-doped graphene electrode shows effective electrocatalytic oxidation of adenine (A), with high sensing towards guanine and adenine compared to that of other heteroatoms doped printed electrodes. The calculated limit of detection for N-doped graphene electrode is 227 ng ml−1 and 322 ng ml−1 with the sensitivity of 1.35 μA ng−1 cm−2 and 1.33 μA ng−1 cm−2 for guanine and adenine sensing, respectively. The fabricated N-doped graphene electrode has open-up a new pathway to develop an economically and environmentally friendly electrodes for DNA sensing.