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Gentiana radix is used in traditional Chinese medicine and has functions of clearing heat and drying dampness, as well as purging liver and gallbladder fire. A highly sensitive and effective strategy for rapid screening and identification of target constituents has been developed by using ultra high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap) in crude and wine-processed . Based on the accurate mass measurement (&lt, 5 ppm), retention times, and MS fragmentation ions, 52 constituents were unambiguously or tentatively characterized from Gentiana radix, including 21 iridoids, 11 flavonoids, 19 xanthones, and a triterpenoid. This study demonstrated that the established method could be a rapid, effective analytical tool for screening and characterization of compounds in the complex systems of . By comparing the structure and peak areas of chemical constituents in crude and wine-processed Gentiana radix, we found that some compounds in crude and wine-processed Gentiana radix were significantly different.

Atractylodis Rhizoma is the dried rhizome of Atractylodes lancea (Thunb.) DC. or Atractylodes chinensis (DC.) Koidz and is often processed by stir-frying with wheat bran to reduce its dryness and increase its spleen tonifying activity. However, the mechanism by which the processing has this effect remains unknown. To explain the mechanism based on the pharmacokinetics of the active compounds, a rapid, sensitive ultra-performance liquid chromatography-tandem mass spectrometry method was developed to analyze atractylenolides I, II, and III, and atractyloside A simultaneously in rat plasma after oral administration of raw and processed Atractylodis Rhizoma. Acetaminophen was used as the internal standard and the plasma samples were pretreated with methanol. Positive ionization mode coupled with multiple reaction monitoring mode was used to analyze the four compounds. The method validation revealed that all the calibration curves displayed good linear regression over the concentration ranges of 3.2&ndash, 350, 4&ndash, 500, 4&ndash, 500, and 3.44&ndash, 430 ng/mL for atractylenolides I, II, and III, and atractyloside A, respectively. The relative standard deviations of the intra- and inter-day precisions of the four compounds were less than 6% with accuracies (relative error) below 2.38%, and the extraction recoveries were more than 71.90 &plusmn, 4.97%. The main pharmacokinetic parameters of the four compounds were estimated with Drug and Statistics 3.0 and the integral pharmacokinetics were determined based on an area under the curve weighting method. The results showed that the integral maximum plasma concentration and area under the curve increased after oral administration of processed Atractylodis Rhizoma.

A simple method that consumes low organic solvent is proposed for the analysis of phthalic acid esters in Chinese white spirit using dispersive liquid-liquid microextraction coupled with sweeping-micellar electrokinetic chromatography. Tetrachloromethane and white-spirit-containing ethanol were used as the extraction and dispersing solvents, respectively. The electrophoresis separation buffer was composed of 5 mM β-cyclodextrin, 50 mM sodium dodecyl sulfate and 25 mM borate buffer (pH 9.2) with 9% acetonitrile, enabling the baseline resolution of the analytes within 13 min. Under the optimum conditions, satisfactory linearities (5-1000 ng/mL, r ≥ 0.9909), good reproducibility (RSD ≤ 6.7% for peak area, and RSD ≤ 2.8% for migration time), low detection limits (0.4-0.8 ng/mL) and acceptable recovery rates (89.6-105.7%) were obtained. The proposed method was successfully applied to 22 Chinese white spirits, and the content of dibutyl phthalate in 55% of the samples exceeded the Specific Migration Limit of 0.3 mg/kg established by the domestic and international regulations.

A selective and low organic-solvent-consuming method of sample preparation combined with high-performance liquid chromatography with diode-array detection is introduced for analysis of phthalic acid esters in edible oils. Sample treatment involves initial liquid–liquid partitioning with acetonitrile, then QuEChERS cleanup by dispersive solid-phase extraction with primary secondary amine as sorbent. Preconcentration of the analytes is performed by ionic-liquid-based dispersive liquid–liquid microextraction, with the cleaned-up extract as disperser solvent and 1-hexyl-3-methylimidazolium hexafluorophosphate as extraction solvent. Under the optimized conditions, correlation coefficients (r) were 0.998–0.999 and standard errors (S y/x ) were 2.67–3.37 × 103 for calibration curves in the range 50–1000 ng g−1. Detection limits, at a signal-to-noise ratio of 3, ranged from 6 to 9 ng g−1. Intra-day and inter-day repeatability, expressed as relative standard deviation, were in the ranges 1.0–6.9 % and 2.4–9.4 %, respectively. Recovery varied between 84 % and 106 %. The developed method was successfully used for analysis of the analytes in 28 edible oils. The dibutyl phthalate content of four of the 28 samples (14 %) exceeded the specific migration limit established by domestic and international regulations.

A very simple, sensitive, and reliable method for the routine determination of riboflavin in cereal grains by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) was established. Two on-line concentration techniques, namely, stacking in reverse migrating micelles (SRMM) and sweeping, were examined to enhance the detection signal. The optimum separation buffer consisted of 20 mM phosphoric acid and 140 mM sodium dodecyl sulfate (SDS), and a hydrodynamic injection of 30 s at 0.5 psi was confirmed for the introduction of a sample. In addition, it was found that salt in sample matrix influenced the performance of SRMM, showing the standard addition method was required for the quantitative analysis. The linearity of the method was good with a range of 0.5–500 ng/mL (r = 0.9990). The limit of detection (LOD) was 0.29 ng/mL at a signal-to-noise ratio of 3. This procedure presented was successfully applied to determine riboflavin in 18 samples of 9 types of cereal grains. The recovery rat...

This paper describes a simple, sensitive and environmentally benign method for the direct determination of aniline and its derivatives in environmental water samples by capillary zone electrophoresis (CZE) with field-enhanced sample injection. The parameters that influenced the enhancement and separation efficiencies were investigated. Surprisingly, under the optimized conditions, two linear ranges for the calibration plot, 1–50 ng/mL and 50–1000 ng/mL (R > 0.998), were obtained. The detection limit was in the range of 0.29–0.43 ng/mL. To eliminate the effect of the real sample matrix on the stacking efficiency, the standard addition method was applied to the analysis of water samples from local rivers.

In this study, two novel sample extraction methods for the analysis of bisphenol A (BPA) in edible oils were developed by using liquid–liquid extraction followed by a dispersive liquid–liquid microextraction (LLE-DLLME) and reversed-phase dispersive liquid–liquid microextraction (RP-DLLME). RP-DLLME showed a superior characteristic over LLE-DLLME and other previously reported procedures because of its easy operation, short extraction time, high sensitivity, low organic solvent consumption and waste generation. The optimized extraction conditions of RP-DLLME for 1.0 g of edible oil diluted in 4 mL of n-hexane were: extractant, 100 μL 0.2 M sodium hydroxide solution (80% methanol, v/v); extraction time, 1 min; centrifugation, 3 min. The determination of BPA was carried out by high performance liquid chromatography coupled with a DAD detector. The method offered excellent linearity over a range of 0.010–0.5 μg g −1 with a correlation coefficient of r > 0.997. Intra-day and inter-day repeatability values expressed as relative standard deviation were 1.9% and 5.9%, respectively. The quantitation limit and detection limit were 6.3 and 2.5 ng g −1 . The target analyte was detected in 5 out of 16 edible oil samples. The recovery rates in real samples ranged from 89.5 to 99.7%.