Study on the Content Determination of Shenbei Beigua Ointment

Objective: A TLCS method was established for the determination of the content of Shenbei Beigua ointment, and the product quality of six samples from two formulations was evaluated. Methods: The determination method was thin-layer chromatography scanning (TLCS), using a developing solvent composed of ethyl acetate–methanol–strong ammonia water (17: 2: 1). The plates were heated at 105 °C for 5 minutes, then sprayed with a mixture of dilute bismuth potassium iodide and 1% ferric chloride in ethanol (10: 1), and scanned at a wavelength of 500 nm. Results: Peimine showed good linearity in the concentration range of 0.21–2.1 μg with a correlation coefficient of r = 0.9997, and Peiminine also exhibited good linearity in the same range with r = 0.9995. The accuracy was ≥ 95.0%, and the relative standard deviation (RSD) was ≤ 5.0% (n = 6). Conclusion: This method allows for the simultaneous determination of peimine and peiminine, providing a reliable reference for the quality control of the product.