Resonance energy transfer based electrochemiluminescence and fluorescence sensing of riboflavin using graphitic...

Graphitic carbon nitride quantum dots (g-CNQDs) are rarely used in the field of electrochemiluminescence. In this paper, g-CNQDs have a strong and stable electrochemiluminescence (ECL) signal generated in the presence of co-reactant K₂S₂O₈. The ECL signal of g-CNQDs was quenched by the mechanism of resonance energy transfer (RET) between donor g-CNQDs and receptor riboflavin (RF) that is proved by UV-vis absorption spectroscopy, electrochemiluminescence and fluorescence emission spectroscopy analysis technology. Therefore, we achieved detection of the riboflavin content in the drug tablets of vitamin B₂ using ECL and FL. The determination results of ECL showed that the riboflavin content of the drug vitamin B₂ (VB₂) tablets was consistent with the fluorescence (FL) analysis, with wider linear range of 0.02-11 μM and lower minimum detection limit of 0.63 nM (S/N = 3) than FL. Hence, the riboflavin content in human serum was further detected using ECL. The relative standard deviation is less than 6.5%, with an acceptable recovery of 95.33%-104.22%, which means that this sensor has potential applications in the actual sample analysis. As a new ECL luminary, g-CNQDs have opened a new field for the development and application of ECL sensor.