Primary Study of Novel Method for Determination of Saponin in Ziziphi Spinosae Semen (Suan-Zao-Ren) by Digitally Scanning the Photo of the HPTLC Image without Configuration of TLC Scanner Facility

摘要

Conventional quantity determination of Chinese herbal medicines by High-Performance Thin-Layer Chromatography (HPTLC) must be carried out on a TLC scanner for measuring the marker component on the HPTLC plate. Generally the HPTLC image of the herbal drug always takes the photograph as the permanent visual document. Considering the photo of the HPTLC image preserving all the visual quality-related parameters, there might be an alternative cost/effective approach worth studying. It would be presumably applicable to use the exclusively developed software as a virtual scanner instead of the TLC Scanner instrument to do digital scanning, integrating and calculating target components in the photo of the HPTLC image. It means digitally scanning the photo of the HPTLC image solely with software does the same thing as the instrumental scanner does. Based on this protocol, we primarily conducted the assay of the contents of the major saponins, jujuboside a and jujuboside b, in Ziziphi Spinosae Semen (Suan-Zao-Ren). Using home-developed software “digiscan” for acquiring the raw data and integrating the peaks area of the target components with “Origin Pro”, the contents of jujuboside a and jujuboside b can then be calculated respectively. The primary investigated experiment results were well compatible with official HPLC-ELSD method in Chinese Pharmacopoeia. The methodology validation and comparative analysis with HPLC confirmed that the unprecedented method is acceptable. The advantage of the recommended approach is far more simple, flexible and cost/effective than the conventional method, and it can be done at anytime and anywhere once only if the high quality HPTLC image photo is available. There would be a bright perspective for application to other herbal medicines. And the one-stop software for merging digital scanning, integration and calculation together is in progress.