A dual preconcentration method by combining micro matrix solid-phase dispersion extraction with field-enhanced sample injection and micelle to cyclodextrin stacking for sensitive analysis of neutral coumarins.

A rapid, sensitive, environmental friendly dual preconcentration method by combining micro matrix solid-phase dispersion extraction with field-enhanced sample injection and micelle to cyclodextrin stacking has been developed for the determination of furocoumarins. Molecular sieve, KIT-6, was used as an adsorbent in micro matrix solid-phase dispersion process. The important parameters affecting off-line and online CE preconcentration efficiency were optimized.

A Simple and Sensitive Dispersive Micro-Solid-Phase Extraction Coupled with High-Performance Liquid Chromatography for Quantification of Honokiol and Magnolol in Complex Matrices.

Background: Honokiol and magnolol were considered as markers for the analysis of Cortex Magnoliae Officinalis, its related Chinese Patent Medicines and their metabolites. However, the determination of these two analytes in a water-soluble sample is difficult and therefore requires a more efficient method.

Objective: To develop a sensitive method for the determination of honokiol and magnolol in a water-soluble sample for better quality control of Cortex Magnoliae Officinalis and its related Chinese Patent Medicines.

Simultaneous determination of seven compounds in Chinese patent medicines Chenxiangqu by matrix solid-phase dispersion coupled with ultra high performance liquid chromatography and quadrupole time-of-flight mass spectrometry.

A simple, efficient, and sensitive strategy by coupling matrix solid-phase dispersion with ultra high performance liquid chromatography quadrupole time-of-flight mass spectrometry was proposed to extract and determine three types of components (including seven analytes) in Chinese patent medicines Chenxiangqu. The highly ordered mesoporous material Fe-SBA-15 synthesized under weakly acidic conditions was selected as a dispersant in matrix solid phase dispersion extraction for the first time. Several parameters including the mass ratio of sample to dispersant, the type of dispersant, the grinding time, and the elution condition were investigated in this work.

Online preconcentration by electrokinetic supercharging for sensitive determination of berberine and jatrorrhizine in biological samples.

Electrokinetic supercharging, a convenient and powerful online preconcentration technique in capillary electrophoresis, was introduced and evaluated for the determination of two alkaloids, berberine and jatrorrhizine, in mice fecal samples for the first time. The method depended on using a bare fused silica capillary (50 cm × 50 μm i.d.

A sensitive two-step stacking by coupling field-enhanced sample injection and micelle to cyclodextrin stacking for the determination of neutral analytes.

To promote the detection sensitivity of neutral analytes, a sensitive two-step stacking strategy by coupling field-enhanced sample injection and micelle to cyclodextrin stacking in reverse migrating micelles MEKC has been established by selecting jujuboside A and B as models. The stacking mechanism, affecting factors as well as analytical performances of the proposed method were investigated. Compared with typical injection, the sensitivity enhancement factors of this method were up to 140- and 152-fold for jujuboside A and B, respectively.

On-line synergistic stacking in capillary zone electrophoresis featuring field-amplified sample stacking and micelle to cyclodextrin stacking in the determination of two alkaloids in complicated matrix samples.

A novel on-line synergistic proconcentration strategy coupling field-amplified sample stacking and micelle to cyclodextrin stacking for cationic analytes in capillary zone electrophoresis has been proposed and applied for the separation and determination of two alkaloids, matrine, and oxymatrine in complicated matrix samples. The approach was performed by the long injection of sample in a low-conductivity sodium dodecyl benzene sulfonate solution followed by the injection of hydroxypropyl-β-cyclodextrin solution in higher conductivity. The stacking mechanism of this method has been expounded and parameters affecting stacking effect have been optimized in our study.

Microwave-assisted ionic liquid-based micelle extraction combined with trace-fluorinated carbon nanotubes in dispersive micro-solid-phase extraction to determine three sesquiterpenes in roots of Curcuma wenyujin.

Introduction: Germacrone, furanodiene and β-elemene are the representative bioactive compounds in Curcuma species. The conventional extraction methods of these three sesquiterpenes are usually time-consuming and require a large volume of hazardous organic solvents. Thus, a fast and reliable method for extracting these sesquiterpenes from Curcuma plant is required urgently.

New Vortex-Synchronized Matrix Solid-Phase Dispersion Method for Simultaneous Determination of Four Anthraquinones in Cassiae Semen.

In this study, a green ionic-liquid based vortex-synchronized matrix solid-phase dispersion (VS-MSPD) combined with high performance liquid chromatography (HPLC) method was developed as a quantitative determination method for four anthraquinones in Cassiae Semen. Two conventional adsorbents, C and silica gel were investigated. The strategy included two steps: Extraction and determination.

A sensitive dispersive micro solid-phase extraction coupled with high performance liquid chromatography for determination of three flavonoids in complex matrics by using crab shell as a sorbent.

A sensitive dispersive micro solid-phase extraction coupled with HPLC has been developed for preconcentration and determination of three flavonoids (quercetin, kaempferol, and isorhamnetin) in complex matrix samples. Parameters that affect extraction efficiency have been optimized. The optimal extraction conditions are using 2 μg/mL of crab shell as the sorbent, extraction for 2 min at pH 7, and then eluting with 100 μL of methanol.

Over 1000-fold improvement in an online preconcentration of trace anionic compounds by capillary electrophoresis with ionic liquid micelle-based three-step stacking.

A sensitive, simple, and environmentally friendly online three-step stacking strategy combining field-enhanced sample injection, sweeping and micelle to solvent stacking has been developed to determine trace amounts of organic anionic analytes in complex biological samples. A green ionic liquid, 1-dodecyl-3-methylimidazolium hydrogen sulfate, was first introduced as a micellar solution and used for electroosmotic flow reversal in this stacking strategy. The mechanism of stacking has been discussed, and parameters affecting three-step stacking preconcentration efficiency have been optimized.

Molecular-sieve-based matrix solid-phase extraction combined with field-amplified sample stacking in capillary electrophoresis for the determination of three organic acids in a complex solid matrix.

A simple, convenient, and sensitive method that involves combining matrix solid-phase dispersion extraction with field-amplified sample stacking in capillary electrophoresis has been developed for the determination of organic acids in a complex solid matrix. Mesoporous molecular sieve, MCM-48, was synthesized by a hydrothermal method and selected as the adsorbent in matrix solid-phase dispersion. After fast extraction, the enriched analytes were back-extracted into a basic aqueous solution for field-amplified sample stacking in capillary electrophoresis.