Abstract:

To establish a robust quality control standard for Yuzhu pharyngitis granules, thin-layer chromatography (TLC) was employed for the qualitative identification of Glycyrrhizae Radix et Rhizoma, Scrophulariae Radix, and Menispermi Rhizoma, while high-performance liquid chromatography (HPLC) was utilized for the quantitative determination of buddleoside. Chromatographic separation was achieved on an Agilent 1260 system equipped with a Kromasil C₁₈ column (4.6 mm × 250 mm, 5 μm). The mobile phase consisted of methanol and 1% acetic acid solution (49:51, v/v), delivered at a flow rate of 1.0 mL/min. Detection was performed at a wavelength of 334 nm, with the column temperature maintained at 30 °C and an injection volume of 10 µL. The TLC profiles of Glycyrrhizae Radix et Rhizoma, Scrophulariae Radix, and Menispermi Rhizoma exhibited distinct, well-resolved spots without interference from the negative control, indicating high specificity of the method. The calibration curve for buddleoside demonstrated excellent linearity over the range of 0.0087–0.4344 µg (n = 6), with a correlation coefficient (r) of 0.9999. The relative standard deviations (RSDs) for precision, stability, and repeatability were all below 2.0% (n = 6), confirming the method’s reliability. The average recovery was 100.8% with an RSD of 1.5% (n = 9), reflecting high accuracy. Analysis of three independent batches yielded a mean buddleoside content of 0.28 mg/g (n = 3), and it was recommended that the content in Yuzhu pharyngitis granules should not be less than 0.22 mg/g. Overall, the established method demonstrated excellent stability, accuracy, and reproducibility, and was therefore suitable for application as a standardized quality control protocol for Yuzhu pharyngitis granules.

Key words: Yuzhu pharyngitis granules, TLC, Content determination, Quality standard, Buddleoside