Green synthesis of doped fluorescent carbon dots for the detection of phosphate and morin in environmental water samples and living organisms

：Green emitting fluorescent carbon dots （NCDs） with quantum yield of 16.6% were successfully synthesized by one-step hydrothermal method using glucose as carbon source and m-phenylenediamine as dopant without adding any organic solvent. The particle size，morphology，and surface functional groups of NCDs were characterized，and it was found that NCDs were spherical with obvious lattice stripes. The surfaces of NCDs are rich in hydrophilic groups such as-OH，-COOH and-NH. Fluorescence spectroscopy showed that NCDs exhibited excitation dependence. The quenching mechanism of PO4 3- on NCDs was determined by UV absorption spectroscopy，fluorescence decay curve，and changes in quenching constants at different temperatures，which belonged to dynamic quenching. The linear range for the detection of PO4 3- was 0.1-10 µμmol/L with a detection limit of 39.4 nmol/L. The quenching mechanism of morin on NCDs was a combination of internal filtration effect and static quenching. The linear range of morin was 0.1-15 µμmol/L with a detection limit as low as 44.8 nmol/L. 3-The spiked recoveries for the detection of PO4 and morin in environmental water and biological samples were 96.2%-104.4%. © 2024, Youke Publishing Co.,Ltd. All rights reserved.