A rapid and sensitive electrochemiluminescent sensor for nitrites based on C3N4 quantum dots on C3N4 nanosheets

Nitrite, an inorganic anion, is widely applied in various fields. Excessive nitrites are harmful to humans and the environment. Here we report on preparation of a nanocomposite, C3N4 quantum dots on C3N4 nanosheets (CNQD@CNNS). With the use of this nanocomposite, we developed a rapid and sensitive electrochemiluminescent (ECL) sensor based on a CNQD@CNNS-modified glassy carbon electrode (GCE). The CNQD@CNNS-modified GCE exhibited strong ECL response using S2O82- as the coreactant. In the presence of nitrites, ECL intensity obviously decreased. After optimizing the dosage of CNQD@CNNS and concentration of co-reactant, the ECL sensor showed a wide linear range (0.28-40 mu M) and good detection limit (0.12 mu M) and selectivity. Further, the proposed ECL sensor was also used to assay nitrites in extract of sausage with satisfactory results.