Chemical profiling and quality evaluation of Pogostemon cablin Benth by liquid chromatography tandem mass spectrometry combined with multivariate statistical analysis.

Pogostemon cablin Benth (PCB) is a well-known traditional Chinese medicine that has been used for treatment of many ailments for several centuries. In presently, the chemical profiling and quality control study of PCB has mainly concentrated on the volatile fractions. However, the non-volatile chemical profile of PCB was still unclear. In this study, 73 non-volatile constituents (i.e., 33 flavonoids, 21 organic acids, 9 phenylpropanoids, 4 sesquiterpenes, 3 alkaloids, and 3 other types of compounds) were identified and characterized in PCB using high performance liquid chromatography coupled with quadruple time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS). Meanwhile, to assess PCB samples, an established HPLC-Q-TOF-MS fingerprint was combined with multivariate statistical analysis that included similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least squares-discriminant analysis (OPLS-DA). The PCB samples could be classified into two groups (herbal decoction pieces and processed medicinal materials), and acteoside, isoacteoside, 4',6-Dihydroxy-5,7-dimethoxyflavone, pachypodol and pogostone were screened as the potential chemical markers that attributed classification. In addition, nine representative components (pachypodol, vicenin-2, apigenin, rhamnocitrin, acteoside, isoacteoside, chlorogenic acid, azelaic acid and pogostone) in PCB were simultaneously determined by using an ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UPLC-QQQ-MS/MS). This study is the first to describe the chemical profile of PCB using liquid chromatography tandem mass spectrometry, which would improve our understanding of the substance basis of PCB and is helpful to the PCB further quality evaluation.

Pharmacokinetic studies of six major 2-(2-phenylethyl) chromones in rat plasma using ultra high performance liquid chromatography with tandem mass spectrometry after oral administration of agarwood ethanol extract.

In this study, a simple, quick, sensitive and reliable method utilizing ultra-high performance liquid chromatography with tandem mass spectrometry method was validated for simultaneous quantification of six main 2-(2-phenylethyl) chromones, including agarotetrol, isoagarotetrol, (5S,6R,7R,8S)-5,6,7,8-tetrahydroxy-(4-methoxyphenethyl)-5,6,7,8-tetrahydro-4H-chromen-4-one, 8-chloro-2-(2-phenyl ethyl)-5,6,7-trihydroxy-5,6,7,8-tetrahydrochromone, 6,7-dimethoxy-2-(2-phenylethyl) chromone, and 2-(2-phenylethyl) chromone in rat plasma after oral administration of agarwood ethanol extract. Separation was performed on a Waters ACQUITY UPLC BEH C18 column (2.1 × 100 mm, 1.7 µm) using gradient elution with mobile phase of 0.2% formic acid-water and acetonitrile. The tandem mass was performed in the multiple reaction monitoring mode with positive ionization. The calibration curves indicated good linearity (r2  > 0.99) over the corresponding concentration range. The precision and accuracy were within the acceptable range. Mean absolute recoveries of all analytes were between 73.31% and 94.76%, and the relative standard deviations of matrix effects were not higher than 15%. The six analytes were proven to be stable during sample storage and analysis procedures. The validated method was successfully applied to pharmacokinetic study of six 2-(2-phenylethyl) chromones in rat after oral administration of agarwood ethanol extract for the first time. This study could serve as a reference and provide theoretical guidance for further pharmacodynamic research and clinical applications of agarwood.

Rapid analysis of short- and medium-chain chlorinated paraffins in wine by dispersive liquid-liquid micro-extraction coupled with high performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry.

This study established a simple and rapid method for determination of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) by dispersive liquid-liquid micro-extraction coupled with high performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF/MS) in white and red wines. Affecting variables, including extraction solvent, salt concentration, ultrasound-vortex conditions and ethanol content, were evaluated. Under optimized conditions, the limit of detection (LODs) for SCCPs and MCCPs were in the range of 0.15-3.00 ng mL-1 and 0.08-2.50 ng mL-1, respectively. The spiked recoveries of SCCPs and MCCPs from white and red wine ranged from 63.2% to 127%. The method is precise with intra- and inter-day variations within 14.0% and 17.0%, respectively. SCCPs and MCCPs in wines from china varied widely, from

Development a simple and rapid HPLC-ESI-Q-TOF/MS method for determination of short- and medium- chain chlorinated paraffins in human serum.

This study established a simple and rapid method for simultaneous determination of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in human serum by high performance liquid chromatography coupled with electron spray ionization quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF/MS). A simple pretreatment procedure of protein precipitation by acetonitrile coupled with liquid-liquid extraction by n-hexane was employed for extraction and purification. The purified samples were separated by a PFP chromatographic column. This method could effectively eliminate the matrix effect by lipids and other matrix substances in serum samples with less time and solvent consuming. 76 congener groups of SCCPs and MCCPs with C10-C17 and Cl5-Cl13 were quantified by their [M-H]- ions. Method detection limit (MDL) were 1.0-8.0 ng mL-1 for ∑SCCPs and ∑MCCPs. Recoveries were 98.4 ±â€¯4.42%, 98.8 ±â€¯3.96% and 90.7 ±â€¯2.79% for SCCPs and 93.1 ±â€¯6.67%, 108 ±â€¯1.21% and 90.8 ±â€¯3.78% for MCCPs at spiking concentrations of 20, 50 and 200 ng·mL-1, respectively. The relative standard deviations (RSDs) of intra- and inter-day variations were 1.41% and 9.84% for SCCPs, and 4.23% and 6.26% for MCCPs. The suitability of the developed method was demonstrated through the application to analysis of SCCPs and MCCPs in human serum samples.

The study of the constituents and source of toxicants in poisonous honey.

A novel method for non-target screening of toxicants in poisonous honey was established in this study. Poisonous honey and nontoxic honey were contrastive detected using liquid chromatography quadrupole-time-of-flight mass spectrometry and analyzed by Mass Profiler Professional Software. 4 poisonous alkaloids were screened out and confirmed by comparison with reference compounds. In order to investigate the source of these poisonous alkaloids, 6 poisonous alkaloids, ubiquitous in Gelsemium elegan, from honey, honeybees, pollen in honeycomb and different organs of Gelsemium elegan, were quantified by liquid chromatography triple-quadrupole tandem mass spectrometry. The results showed that alkaloids composition characteristics in honey, honeybees, and pollen were similar to those in the flower and bud of Gelsemium elegan and significant different from those in leave, stem and root. This result demonstrated that poisonous alkaloids in honey were come from the gathering honey process. This strategy provided an efficient and rapid method for non-target screening of toxicants in food.

[Identification of dalbergia odorifera and dalbergia spp by solid phase microextraction-gas chromatography-mass spectrometry].

In addition to species identification, the volatile components of dalbergia odorifera and dalbergia spp, were investigated by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). Small amounts of powder samples were acquired by drilling from dalbergia, then the volatile components of the powder samples were concentrated by SPME, and separated by AB-FFAP polar capillary GC column. Of all the volatile components, twenty types were identified, and two pairs of them, 2-(1,1-dimethylethyl)-5-heptyl-5-methyl-1,3-dioxolan-4-one and 2,6,10-trimethyl-7,10-epoxy-2,11-dodecadien-6-ol, 2-methylbutylidene-cyclopentane and 2-(5-methyl-furan-2-yl)-propionaldehyde, could be considered specific volatile components for the identification of dalbergia odorifera and dalbergia spp, and the relative contents of these two pairs were compared for the species identification analysis. The method has the advantages of less sample requirement, simple operation, and no construction damage. The method is suitable for the research of volatile components and species identification analysis of dalbergia odorifera and dalbergia spp, and has broad prospective application in the analysis of furniture, art collections and raw wood of dalbergia.

[Simultaneous rapid determination of 81 glucocorticoids in cosmetics by dispersive solid phase extraction and liquid chromatography-tandem mass spectrometry].

A novel method was developed for the simultaneous rapid determination of 81 illegally added glucocorticoids (GCs) in cosmetics using dispersive-solid phase extraction (d-SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The analytes were extracted by acetonitrile after dispersing with water, and then purified using the C18 and primary secondary amine (PSA). The chromatographic separations were performed on a Poroshell 120 PFP column (100 mm×2.1 mm, 2.7 µ m) under multiple chromatographic retention modes. Acetonitrile and 0.2% (v/v) acetic acid aqueous solution were used as mobile phases with gradient elution, and all the 10 groups of isomers were baseline separated. The qualitative identification and quantitative analysis of the 81 GCs were operated in the electrospray ionization positive mode using dynamic multiple reaction monitoring (DMRM). The 81 GCs finally were quantified by internal standard method. The correlation coefficients of linear calibration curves were greater than 0.99 in the corresponding mass concentration ranges. The average recoveries of the 81 GCs at three spiked levels ranged from 68.8% to 105.3% with relative standard deviations (RSDs) of 2.9%-13.1% (n=6). The LODs (S/N ≥ 3) and LOQs (S/N ≥ 10) were 0.002-0.006 µ g/g and 0.005-0.020 µ g/g, respectively. A number of 137 cosmetic samples submitted by customers were screened. Sixteen positive samples were found, and the contents of GCs were from 16.9 µ g/g to 158 µ g/g. The results showed that the new method is simple, rapid, sensitive and reliable, and it is suitable for qualitative and quantitative screening analysis of the 81 GCs in cosmetics simultaneously.

[Multiresidue analysis of 63 veterinary drugs in meat by dispersive solid-phase extraction and high performance liquid chromatography-tandem mass spectrometry].

A novel multiresidue analytical method has been developed and validated for the determination of five classes of veterinary drugs including 18 ß-lactams, 15 quinolones, 21 sulfonamides, 3 sulfonamide potentiators and 6 antiparasitics in meat using dispersive solid-phase extraction (dispersive-SPE) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The analytes were extracted with a vortex mixer by 0.1 mol/L Na2 EDTA solution and acetonitrile containing 1% (v/v) acetic acid, and then the extracts were purified using dispersive-SPE with C18 sorbent. Electrospray ionization mass spectrometry was operated in positive mode using dynamic multiple reaction monitoring (DMRM) for the qualitative and quantitative analysis of the 63 analytes after the separation on a Poroshell EC-C18 column (100 mm x 2.1 mm, 2.4 µm). The correlation coefficients of linear calibration curves were over 0.99 in the corresponding concentration ranges. The average recoveries of the 63 analytes ranged from 62.2% to 112.0%, and the relative standard deviations (RSDs) were 3.1%-16.3% in spiked meat (pork, beef and chicken muscle) at three levels. The limits of detection (LODs, S/N ≥ 3) and the limits of quantification (LOQs, S/N ≥ 10) were 0.1-3.0 µg/kg and 0.5-10.0 µg/kg, respectively. The method is simple, rapid, sensitive, reliable and suitable for the determination of residues in animal products.

Identification and determination of the saikosaponins in Radix bupleuri by accelerated solvent extraction combined with rapid-resolution LC-MS.

A method based on accelerated solvent extraction combined with rapid-resolution LC-MS for efficient extraction, rapid separation, online identification and accurate determination of the saikosaponins (SSs) in Radix bupleuri (RB) was developed. The RB samples were extracted by accelerated solvent extraction using 70% aqueous ethanol v/v as solvent, at a temperature of 120 degrees C and pressure of 100 bar, with 10 min of static extraction time and three extraction cycles. Rapid-resolution LC separation was performed by using a C(18) column at gradient elution of water (containing 0.5% formic acid) and acetonitrile, and the major constituents were well separated within 20 min. A TOF-MS and an IT-MS were used for online identification of the major constituents, and 27 SSs were identified or tentatively identified. Five major bioactive SSs (SSa, SSc, SSd, 6''-O-acetyl-SSa and 6''-O-acetyl-SSd) with obvious peak areas and good resolution were chosen as benchmark substances, and a triple quadrupole MS operating in multiple-reaction monitoring mode was used for their quantitative analysis. A total of 16 RB samples from different regions of China were analyzed. The results indicated that the method was rapid, efficient, accurate and suitable for use in the quality control of RB.