Off-line comprehensive two-dimensional high-performance liquid chromatography system with size exclusion column and reverse phase column for separation of complex traditional Chinese medicine Qingkailing injection

Comparative pharmacokinetics of baicalin and geniposide in juvenile and adult rats after oral administration of Qingkailing Granules

Objective

To explore the effect of age on Qingkailing Granules disposition by comparing the pharmacokinetics of geniposide and baicalin in juvenile and adult rats.

Methods

A simple and rapid LC-MS/MS method was developed and validated to simultaneously determine geniposide and baicalin in rat plasma after a simple protein precipitation. The analytes were separated on an Agilent ZORBAX Extend-C₁₈ column. The mobile phase consisted of acetonitrile and water with 0.1% (volume percent) formic acid at a flow rate of 0.6 mL/min. The ionization was conducted using an ESI source in negative ion mode. Multiple reaction monitoring was used for quantification at transitions of m/z 445.0 → m/z 268.9 for baicalin, m/z 433.2 → m/z 225.0 for geniposide, m/z 431.0 → m/z 341.0 for vitexin (IS). Juvenile and adult rats were administrated Qingkailing Granules (3 g/kg) orally. Plasma concentrations of baicalin and geniposide were determined by LC-MS/MS.

Results

The linear ranges of the analytes were 1–1000 ng/mL for baicalin and 2–2000 ng/mL for geniposide. The method was successfully applied to compare the pharmacokinetics of the analytes between juvenile and adult rats after oral administration of Qingkailing Granules. AUC was bigger in adult rats, while t_1/2 was longer in juvenile rats.

Conclusion

These results suggested that the absorption and elimination of baicalin and geniposide in juvenile rats was lower than that in adult rats. Additional attention should be paid to the pharmacokinetic difference when Qingkailing Granules were used in children.

Multidimensional information-based HPLC technologies to evaluate traditional chinese medicine

Traditional Chinese medicines (TCMs) are usually complex mixtures and contain hundreds of chemically different constituents, which make the quality control (QC) of crude drugs and their medical preparations extremely difficult. In the past years, with the rapid development of modern instrumental analysis and computer-aided data processing techniques, great progress has been made in the research of quality standards and the development of QC techniques. Among them, the use of the high-performance liquid chromatography (HPLC) technique is one of the best approaches because of its high separation efficiency. However, one-way separation, single detection methods or data processing cannot meet the needs of the QC of TCMs. Multidimensional information-based HPLC technologies such as two-dimensional HPLC, HPLC coupled with several different detection methods and HPLC fingerprint combined with multicomponent quantification have solved this problem with their comprehensive analysis; these methods have gradually been accepted by more researchers for further in-depth study. The present work provides an overview of the development of QC for TCMs based on HPLC technologies with modern hyphenated techniques, multiseparation methods and some common data processing methods in fingerprint spectra over the last six years.

Separation of Liquiritin by Two-Dimensional Liquid Chromatography

Two-dimensional liquid chromatography (2DLC) is an important technology for the separation and analysis of complex samples. Liquiritin, an important active component in licorice, was chosen as the target compound and it was separated by three kinds of off-line 2DLC, i.e. size exclusion chromatography × reversed phase chromatography, normal phase × reversed phase chromatography and reversed phase chromatography × reversed phase chromatography (SEC×RP, NP×RP and RP×RP). The chromatographic conditions were selected and the 2D systems were combined. The results show that it is feasible to separate Liquiritin from licorice extract using 2DLC. Among the 2D modes mentioned above, the highest purity of Liquiritin was obtained in the RP×RP mode, and the concentration of Liquiritin was increased most significantly in the NP×RP mode.

Recent analytical approaches in quality control of traditional Chinese medicines--a review

Traditional Chinese medicines (TCMs) are gaining more and more attention all over the world, due to their specific theory and long historical clinical practice. But the uncontrollable quality is a bottleneck for its modernization and globalization. This paper reviewed the recent analytical methods in the quality control of TCMs, including screening strategies of bioactive markers from TCMs through biochromatographic methods, the traditional chromatographic methods, DNA methods, as well as the spectroscopic methods, including FT-IR, NIR and NMR. The comprehensive methods, such as fingerprint and multi-component quantification are emphasized; hyphenated techniques, like HPLC-MS, GC-MS, CE-MS, LC-NMR, chemometric methods, and combination of chemical and biological methods, such as biofingerprint, metabolic fingerprint are now more and more widely used in TCMs. In a few word, the analysis and quality control of TCMs are moving towards an integrative and comprehensive direction, in order to better address the inherent holistic nature of TCMs.

Multidimensional liquid phase separations for mass spectrometry

Large part of the current research in biology, medicine, and biotechnology depends on the analysis of DNA (genomics), proteins (proteomics), or metabolites (metabolomics). The advances in biotechnology also command development of adequate analytical instrumentation capable to analyze minute amounts of samples. The analysis of the content of single cells may serve as an example of ultimate analytical applications. Most of the separation techniques have been developed in the last three decades and alternative approaches are being investigated. At present, the main protocols for analyses of complex mixtures include 2-DE (IEF) followed by electrophoresis in SDS polyacrylamide gel (SDS-PAGE) and chromatographic techniques. Information-rich techniques such as MS and NMR are essential for the identification and structure analysis of the analyzed compounds. High resolution separation of the individual sample components is often a prerequisite for success. High resolution proteomic analysis in the majority of laboratories still relies on the time consuming and laborious offline methods. This review highlights some of the important aspects of 2-D separations including microfluidics.

Recent developments in sample preparation techniques for chromatography analysis of traditional Chinese medicines

Traditional Chinese medicines (TCMs) have a long history dating back thousands of years. Recently, there has been increasing interest worldwide in the use of TCMs for the prevention and treatment of various illnesses. In China, a large number of analytical tools, especially chromatographic techniques have been used to analyze the constituents of TCMs in order to control their quality and discover new bioactive compounds. In this paper, recent developments in sample preparation techniques for the extraction, clean-up, and concentration of analytes from TCMs are compared. These techniques include headspace solid-phase microextraction (HS-SPME), headspace liquid-phase microextraction (HS-LPME), microwave-assisted extraction (MAE), supercritical-fluid extraction (SFE), pressurized-liquid extraction (PLE), and microwave distillation (MD).