SO32−-based chemiluminescence in unbuffered solution with ClO2 as oxidant and its analytical application

In this paper, SO32−-chemiluminescence (CL) system in unbuffered solution with ClO2 as oxidant is proposed. ClO2 could oxidize sulfite in unbuffered solution to produce CL emission, and riboflavin could sensitize the ClO2–SO32−-based CL system. The ClO2–SO32−–riboflavin CL reaction was chosen as a model system and explored the possibility of SO32−-based CL system in unbuffered solution. Compared with the reported SO32−-based CL system in strong acid media, the proposed CL system owns its advantages. Combined with flow-injection analysis, the proposed CL system was applied to measurement of riboflavin in pharmaceuticals.