Highly sensitive and selective amperometric nitrite sensor based on electrochemically activated graphite modified screen printed carbon electrode

A novel and sensitive amperometric nitrite sensor has been developed using electrochemically activated graphite (EAG) modified screen printed carbon electrode (SPCE) for the first time. The enhanced oxidation peak current (Ipa) with lower oxidation overpotential (Epa) of nitrite is observed at EAG modified SPCE than that of electrochemically activated SPCE and graphite/SPCE. Under optimum conditions, the linear response of nitrite is found from 0.1 μM to 16.4 mM with a lower limit of detection of 38 nM. The sensitivity is calculated as 0.126 μA μM−1 cm−2. The EAG modified SPCE exhibits its high selectivity in the presence of common ions and biological co-active interfering species. In addition, the fabricated nitrite sensor shows a good repeatability, reproducibility and long term stability along with excellent practicality.