The development of the monograph of a commonly used Chinese medicine, Lini Semen, for the Hong Kong Chinese Materia Medica Standards (HKCMMS) was recorded. HKCMMS is a set of reliable and internationally recognized standards of Chinese medicine. The monograph of Lini Semen was proposed, endorsed, and under editorial phase for the publication of the 9th volume of HKCMMS. In the proposed HKCMMS monograph of Lini Semen, besides regular content such as macroscopic and microscopic identification, and TLC identification, a HPLC fingerprint method and two assay methods were developed. All methods were well-established and validated. TLC identification: Lini Semen n-hexane extract is identified on a HPTLC Silica gel RP-18 plate, with α-linolenic acid and linoleic acid as the markers. The developing system consisted of acetone, acetic acid and dichloromethane in the ratio of 5:4:2. The spraying reagent was 5% sulphuric acid - ethanol solution and the plate was observed under 366 nm. HPLC fingerprint: Fingerprint of Lini Semen was conducted on a HPLC system with a C8 column. Mobile phase consisted of (A) water and (B) acetonitrile and isopropanol (9:1). Six characteristic peaks, including α-linolenic acid and linoleic acid were detected under 210 nm. Assay: α-Linolenic acid and linoleic acid were detected from Lini Semen n-hexane extract under the same HPLC condition of the fingerprint of Lini Semen. The proposed total content of α-linolenic acid and linoleic acid was not less than 0.56%. Secoisolariciresinol diglucoside (SDG) was detected from hydrolysed Lini Semen extract by HPLC system with a C18 column. Mobile phase consisted of (A) water and (B) acetonitrile. The detection wavelength was 280 nm. The proposed content of SDG was not less than 0.81%. Conclusion: It is the first time to propose a HPLC fingerprint and introduce SDG as a assay marker of Lini Semen in a regional standard monograph. The established methods for TLC identification, HPLC fingerprint, assay of the total content of α-linolenic acid and linoleic acid, as well as assay for SDG were validated with in-house and inter-laboratory comparison to prove that the methods are reliable.
|Date of Award
|4 Jul 2018
|Simon Q B HAN (Supervisor)
- High performance liquid chromatography