High-efficient synthesis of carbon quantum dots from orange pericarp as fluorescence turn-on probes for Ca and Zn ion detection and their application in trypsin activity characterization.

Objectives: In this work, we propose an efficient preparation process for the synthesis of natural carbon quantum dots (NCQDs) by the usage of orange pericarp as the carbon natural resource, which is performed through hydrothermal treatment and top-down approaches.

Materials And Methods: The structural, morphological, average size, and optical properties of synthesized NCQDs were investigated via dynamic light scattering (DLS), transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), field emission scanning electron microscope (FESEM), energy dispersive x-ray spectroscopy (EDX), ultraviolet-visible spectroscopy (UV-Vis), and fluorescence PL spectra.

Results: The shape of obtained NCQDs was observed to be spherical in the results of TEM analysis with an average size of 6-7 nm which confirms NCQDs essence.