‘Turn-on’ fluorescence sensing of hydrogen peroxide in marine food samples using a carbon dots–MnO2 probe

A ‘turn-on’ fluorescence method for detection of hydrogen peroxide (H 2 O 2 ) in marine food samples is presented in this article. Using this method, a carbon dots (CDs)–MnO 2 probe was formed in which fluorescence intensity (FI) of CDs was quenched through fluorescence resonance energy transfer by addition of MnO 2 nanosheets. When H 2 O 2 was added into the CDs–MnO 2 solution, the MnO 2 nanosheets formed Mn 2+ ions due to a redox reaction between H 2 O 2 and MnO 2 nanosheets, and CD FI was recovered. Under optimized conditions, the detection limit for H 2 O 2 was 0.87 μM, and analytical linear range was 4–100 μM. Furthermore, this developed fluorescence sensing system was successfully used with satisfactory results to determine trace H 2 O 2 content in marine food samples.