Exploration and optimization of conditions for quantitative analysis of lignans in Schisandra chinensis by an online supercritical fluid extraction with supercritical fluid chromatography system.

An online supercritical fluid extraction with supercritical fluid chromatography system could provide sequential extraction and quantitative analysis of lignans in Schisandra chinensis. Supercritical fluid extraction conditions were optimized at 15 MPa, 50°C, and 4 min with supercritical CO adding 1% methanol; the elution volume and flow rate were set at 6 mL and 2 mL/min to blow extract out of the tank completely. The split-flow rate was confirmed at 2.

Design, synthesis and evaluation of a series of alkylsiloxane-bonded stationary phases for expanded supercritical fluid chromatography separations.

Supercritical fluid chromatography (SFC) today represents an alternative technique in analytical chemistry due to its obvious benefits in kinetic performance and its complementarity to liquid chromatography. In this paper, a series of alkylsiloxane-bonded stationary phases were synthesized and evaluated to expand their SFC applications. Five kinds of non-endcapped C8 stationary phases (C8-1 to C8-5) with increasing bonding density were synthesized, and the carbon content was 3.

[Separation and purification of compounds from using preparative reversed-phase liquid chromatography and preparative supercritical fluid chromatography].

A method based on preparative reversed-phase liquid chromatography (prep-RPLC) and preparative supercritical fluid chromatography (prep-SFC) was developed for the separation and purification of compounds from . A pretreatment method was first developed, including methanol extraction, water precipitation, petroleum ether extraction, etc. Chlorophyll and other strong polar impurities were removed from the samples, and the target components were enriched in petroleum ether extracts.

[Application of off-line two dimensional reversed-phase liquid chromatography/supercritical fluid chromatography to the separation of the seeds of ].

An off-line two dimensional reversed-phase liquid chromatography/supercritical fluid chromatography (2D RPLC/SFC) method was developed for the separation of the seeds of . (.).

[Separation and purification of the components in by two dimensional hydrophilic interaction liquid chromatography- reversed-phase liquid chromatography].

A preparative two dimensional hydrophilic interaction liquid chromatography/reversed-phase liquid chromatography (Pre-2D-HILIC/RPLC) method was established to separate and purify the components in . The pigments and strongly polar components were removed from the crude extract after the active carbon decolorization and solid phase extraction processes. A Click XIon column (250 mm×20 mm, 10 μm) was selected as stationary phase and water-acetonitrile as mobile phases in the first dimensional HILIC.

Preparative separation of the polar part from the rhizomes of Anemarrhena asphodeloides using a hydrophilic C18 stationary phase.

The goal of this study was to develop a method that utilized a hydrophilic C18 stationary phase in the preparative high performance liquid chromatography to isolate the polar part from the rhizomes of Anemarrhena asphodeloides. The results showed that an initial mobile phase of pure water for the separation could greatly increase the retention and solubility of the polar compounds at the preparative scale. Introducing polar groups on the surface of the hydrophilic C18 column together with the use of optimized mobile phase compositions improved the column separation selectivity for polar compounds.

Rapid purification of diastereoisomers from Piper kadsura using supercritical fluid chromatography with chiral stationary phases.

Supercritical fluid chromatography (SFC) with chiral stationary phases (CSPs) is an advanced solution for the separation of achiral compounds in Piper kadsura. Analogues and stereoisomers are abundant in natural products, but there are obstacles in separation using conventional method. In this paper, four lignan diastereoisomers, (-)-Galbelgin, (-)-Ganschisandrin, Galgravin and (-)-Veraguensin, from Piper kadsura were separated and purified by chiral SFC.

Purification of lignans from Fructus Arctii using off-line two-dimensional supercritical fluid chromatography/reversed-phase liquid chromatography.

As a common traditional Chinese medicine, Fructus Arctii has important clinical medical values. Its main components are lignans, which are difficult to separate and analyze because of the complex composition, similar chemical structures, and close properties. In this study, an off-line two-dimensional supercritical fluid chromatography/reversed-phase liquid chromatography method, as well as an effective sample pretreatment method based on hydrophilic interaction chromatography material, was developed to enrich the minor lignan fractions and obtain high-purity compounds.

Development, validation and application of a hydrophilic interaction liquid chromatography-evaporative light scattering detection based method for process control of hydrolysis of xylans obtained from different agricultural wastes.

Purified standards of xylooligosaccharides (XOSs) (DP2-6) were first prepared from a mixture of XOSs using solid phase extraction (SPE), followed by semi-preparative liquid chromatography both under hydrophilic interaction liquid chromatography (HILIC) modes. Then, an accurate quantitative analysis method based on hydrophilic interaction liquid chromatography-evaporative light scattering detection (HILIC-ELSD) was developed and validated for simultaneous determination of xylose (X1), xylobiose (X2), xylotriose (X3), xylotetraose (X4), xylopentaose (X5), and xylohexaose (X6). This developed HILIC-ELSD method was applied to the comparison of different hydrolysis methods for xylans and assessment of XOSs contents from different agricultural wastes.

Hydrophilic interaction liquid chromatography for the separation, purification, and quantification of raffinose family oligosaccharides from Lycopus lucidus Turcz.

A systematic strategy based on hydrophilic interaction liquid chromatography was developed for the separation, purification and quantification of raffinose family oligosaccharides from Lycopus lucidus Turcz. Methods with enough hydrophilicity and selectivity were utilized to resolve the problems encountered in the separation of oligosaccharides such as low retention, low resolution and poor solubility. The raffinose family oligosaccharides in L.

[Structural characterization of Astragalus polysaccharides using partial acid hydrolysis-hydrophilic interaction liquid chromatography-mass spectrometry].

Water-soluble polysaccharides from traditional Chinese medicine (TCM) have properties of broad-spectrum treatment and low toxicity, making them as important components in natural medicines and health products. In order to solve the problem of polysaccharides characterization caused by their complex structures, a "bottom-up" approach was developed to complete the characterization of polysaccharides from Astragalus. Firstly, Astragalus pieces were extracted with hot water and then were precipitated by ethanol to obtain Astragalus polysaccharides.

Preparation and chromatographic evaluation of a newly designed steviol glycoside modified-silica stationary phase in hydrophilic interaction liquid chromatography and reversed phase liquid chromatography.

A diterpene glycoside compound, rebaudioside A (commonly abbreviated as RA), was immobilized onto porous silica surface through "thiol-ene" click chemistry strategy. The successful immobilization of the RA on the silica support was confirmed by FT-IR and elemental analysis. Chromatographic characteristics of the new stationary phase, named Click TE-RA, were evaluated by a set of diverse analytes such as carbohydrates, nucleosides, and organic acids in hydrophilic interaction liquid chromatography (HILIC) mode.

Alkaloids analysis using off-line two-dimensional supercritical fluid chromatography × ultra-high performance liquid chromatography.

In this study, an off-line two-dimensional (2-D) supercritical fluid chromatography (SFC) × ultra-high performance liquid chromatography (UHPLC) method with high orthogonality was developed for the analysis of the practical amide alkaloids fraction from P. longum L. The effects of SFC parameters such as column type, organic modifier, temperature and back-pressure on separation were systematically evaluated.