Selective and sensitive fluorescence turn-on detection of bilirubin using resorcinol-sucrose derived carbon dot

Carbon dots have been prepared from resorcinol and sucrose (rsCDs) hydrothermally, which show green emis-sion at 525 nm with a fluorescence quantum yield (PLQY) of 17.2%. The intense emission of rsCDs is quenched upon the addition of Cu2+. In the presence of bilirubin (BR), the emission intensity is enhanced due to the competitive binding of Cu2+ with bilirubin and hence releasing rsCDs to the sensing medium. It is the first time report on turn-on fluorescence sensing towards BR with a detection limit of 85 nM. Even in the presence of other comparable biomolecules, the sensor is selective and ultrasensitive to bilirubin. A cellulose paper-based sensor strip has also been designed for the naked-eye detection of BR in blood serum. Due to the specific recognition of this rsCDs towards BR, it can be applied to detect BR in practical human serum samples.

Automated summary

In this study, carbon dots (rsCDs) were prepared hydrothermally and showed quenching of fluorescence in the presence of Cu2+ and enhancement of fluorescence in the presence of bilirubin (BR). These rsCDs can be used for naked-eye detection of BR in blood serum with high selectivity and sensitivity.