Detection of Baicalin capsule and Scutellariae Radix based on nitrogen-doped carbon dots as a fluorescence probe

•A method for detection of Baicalin has been established.•The proposed analytical method showed high sensitivity towards Baicalin.•The analytical method was utilized for Baicalin determination in Baicalin capsule.•The analytical method was utilized for evaluate quality of Scutellariae Radix. Nitrogen-doped fluorescent carbon dots (N-CDs) were prepared via hydrothermal synthesis method using citric acid and ethylenediamine as raw materials. The synthesized N-CDs were characterized by transmission electron microscopy (TEM) and multi-spectroscopic techniques. A fluorescent sensor based on the inner filter effect (IFE) was successfully established using synthesized carbon dots to detect the content of Baicalin in Baicalin capsule and the quality of Scutellariae Radix. The Baicalin linear range of the method is 1.6–72 μg·mL−1 (r = 0.9992), the detection limit is 1.0 μg·mL−1 (3-foldσ), and the precision was 0.2%. Furthermore, the N-CDs probe was used to evaluate quality of Scutellariae Radix.