Preparation of biomass-waste-derived carbon dots from apricot shell for highly sensitive and selective detection of ascorbic acid

An ascorbic acid (AA) fluorescence sensor was built using biomass-waste-derived carbon dots (CDs). The CDs were prepared using apricot shell biomass, which serves as an abundant starting source. The prepared CDs displayed good dispersion, uniform particle size, high photostability, and a greenish-yellow luminescence. The experimental results confirmed the greenish-yellow fluorescence was selectively quenched by Fe3+ and then recovered selectively upon adding AA to the Fe3+-CD system, exhibiting an off-on phenomenon. The recovered fluorescence intensity was linear with AA concentration. The linear range is 1–100 μM and detection limit is 40 nM. Analysis of a real sample was also carried out to determine the AA content in human urine. The proposed strategy allowed efficient use of discarded apricot shells that have good economic, environmental, and medical benefits.