Millisecond dynamics of colloidal suspension studied by X-ray photon correlation spectroscopy at the Shanghai Synchrotron Radiation Facility

X-ray photon correlation spectroscopy(XPCS)has emerged as a powerful tool for probing the nanoscale dynamics of soft condensed matter and strongly correlated materials owing to its high spatial resolution and penetration capabilities.This technique requires high brilliance and beam coherence,which are not directly available at modern synchrotron beamlines in China.To facilitate future XPCS experiments,we modified the optical setup of the newly commissioned BL10U1 USAXS beamline at the Shanghai Synchrotron Radiation Facility(SSRF).Subsequently,we performed XPCS measurements on silica suspensions in glycerol,which were opaque owing to their high concentrations.Images were collected using a high frame rate area detector.A comprehensive analysis was performed,yielding correlation functions and several key dynamic parameters.All the results were consistent with the theory of Brownian motion and demonstrated the feasibility of XPCS at SSRF.Finally,by carefully optimizing the setup and analyzing the algorithms,we achieved a time resolution of 2 ms,which enabled the characterization of millisecond dynamics in opaque systems.

Extraction of the Main Ingredients from Chuanxiong by CO₂Supercritical Fluid Extraction

As one of the most frequently used medicinal herbs in China, Chuanxiong Rhizoma (Chuanxiong) is notable for its beneficial effects in alleviation of cardio- and cerebro- vascular disorders. Results from previous phytochemical, pharmacological and pharmacokinetic studies supported the contributions of 10 main components, namely ferulic acid (3), senkyunolide I (4), senkyunolide H (5), senkyunolide A (6), coniferylferulate (7), Z-ligustilide (8), sedanolide (9), 3-butylidenephthalide (10), riligustilide (11) and levistolide A (12), for therapeutic outcomes of the herb. To prepare a Chuanxiong extract, which is selectively enriched with these main components, the supercritical fluid extraction (SCFE) technique using CO2 was chosen in the present study due to its superiority in extraction of lipophilic components, especially thermo-labile components from natural products. Eight Chuanxiong samples were extracted under different SCFE conditions. Contents of 3 - 12 in SCFE extracts and remained in herbal residues were determined using HPLC-UV and compared with those in 95% ethanol extracts of the respective herbal samples. The results showed that contents of 3 - 12 were generally enriched by SCFE with higher recoveries achieved for lipophilic constituents, including the three most abundant constituents 6, 7 and 8. Moreover, extraction yield of the less lipophilic 3, 4 and 5 was improved by adding ethanol as entrainer. Higher flow rate of CO2 (10 - 13 L/h vs 9 - 12 L/h) enhanced the overall extraction, while lower temperature (32℃ vs 40℃) reduced degradation of thermo-labile compounds, in particular 7, 8 and 10. Our established SCFE condition yielded high extraction recoveries for both total (75.6%) and three major chemical ingredients (6: 83.5%, 7: 77%, 8: 78.3%) from Chuanxiong with an adequate overall reproducibility, demonstrating a successful application of SCFE in selective enrichment of certain ingredients and efficient extraction of thermo-labile components from medicinal herbs using specifically designed SCFE conditions.

LC-MS-based Metabolomics in Traditional Chinese Medicines Research: Personal Experiences

LC-MS-based metabolomics has being widely used in traditional Chinese medicines （TCMs） research due to the great coverage of mass ranges, high sensitivity to detect metabolites, and no need of sample derivatization. Herein, we reviewed our research on the applications of LC-MS-based metabolomics in TCMs research over the past decade in the following aspects： herbal authentication, determination of herb harvest time, chemical transformation of herbs during post-harvest handlings （sulfurfumigation and drying）, discrimination of raw and processed herbs, chemical transformation of TCMs during preparation, screening endogenous toxic compounds in TCMs, unveiling synergistic mechanisms between small molecules （such as saponins） and polysaccharides in TCMs, revealing synergistic actions of TCMs with chemical drugs, which demonstrated that metabolomics is a superior strategy in TCMs research concerning the holistic perspectives.