Determination of brominated diphenyl ethers in atmospheric particulate matter using selective pressurized liquid extraction and gas chromatography–mass spectrometry with a negative chemical ionization

This study describes the development and validation of a sensitive and reliable method for determination of polybrominated diphenyl ethers（PBDEs）in atmospheric particulate matter using selective pressurized liquid extraction（SPLE）and gas chromatography–mass spectrometry with a negative chemical ionization（GC-NCI-MS）.Extraction and clean-up were performed using PLE with 2 g florisil and 3 g silica placed in the extraction cells.Under optimal conditions,14 PBDEs were extracted at 70℃ using hexane/dichloromethane（50：50,v/v）as solvent.Validation of SPLE returned excellent recoveries for most analytes,with relative standard deviations mostly below20%.Method detection limits ranged from 0.13 to15.38 ng·mL^-1 for the GC-MS analyses.The method was successfully applied to atmospheric particulate matter of Beijing,where analytes were detected in the range of182.79 to 468.99 pg·m^-3.

Effect of severe acute pancreatitis on pharmacokinetics of Da-Cheng-Qi Decoction components

AIM:To investigate the effect of severe acute pan- creatitis(SAP)on pharmacokinetics of Da-Cheng-Qi Decoction(DCQD)components in rats. METHODS:Rats were divided into SAP group and sham-operation group as a control group(n=6). Rhein,chrysophanol,rheochrysidin,magnolol,hesperidin and naringin in DCQD were quantified in rat serum by high performance liquid chromatography tandem mass spectrometry for studying their pharmacokinetics. RESULTS:Early absorption of each DCQD component was tended to degrade in SAP group after treatment with DCQD by gavage.The Cmax(chrysophanol,P= 0.0059;rheochrysidin,P=0.0288;magnolol,P= 0.0487;hesperidin,P=0.0277;naringin,P=0.0023) and AUC(rhein,P=0.0186;chrysophanol,P=0.0013; magnolol,P=0.001;hesperidin,P=0.0081;naringin, P=0.0272)of DCQD component were obviously lower in SAP group than in control group.The T1/2α of chrysophanol and rheochrysidin(P=0.0467 and 0.0005,respectively)and Tmax of chrysophanol and rheochrysidin(P=0.0101 and 0.0037,respectively) lasted longer in SAP group than in control group. CONCLUSION:SAP can significantly impact the ab-sorption of DCQD components in rats and their phar-macokinetic parameters.

Economic and Qualitative Traits of Italian Alps Saffron

Saffron, obtained from the flower stigmas of Crocus sativus L., is one of the most expensive food spices. The introduction of saffron in alpine areas could help to broaden and diversify the activities of mountain multifunctional farms, with a positive impact on economy and land management. According to ISO 3632(2010/2011), saffron can be classified into three categories of quality(I, II, III) depending on the concentration of the three main metabolites responsible for its characteristic colour, flavor and aroma: Crocin, Picrocrocin and Safranal. This study represents the first investigation of the quality of saffron produced in the Italian Alps evaluated with spectrophotometry, HPLC, solid-phase microextraction(SPME), and gas chromatographic analysis combined with mass spectrometry(GC/MS). The experiments used Crocus sativus stigmas produced in 2012-2013 in different areas of the Central Italian Alps were located at an altitude between 720 and 1200 m a.s.l.. Results obtained were compared to commercial saffron. The analyses confirmed that all samples can be classified in the first quality category according to the ISO classification. This high quality is also confirmed by HPLC analysis. Moreover, the SPME-GC/MS analysis identified some differences in the aromatic profile of saffron samples, in particular regarding safranal concentration. A preliminary assessment of the economic viability of high quality saffron production for local markets was also performed. Our study provides valid information regarding the quality and economic sustainability of saffron production in the alpine area confirming this crop as a good candidate for a new source of income for multifunctional farms in mountain areas.

Study on the basic nitrogen compounds from coal-derived oil

The distillation range analysis and elemental analysis of fractioned direct liquefied oil were conducted. Each fraction of liquefied oil contains some nitrogen compounds. Using the acid extraction method and gas chromatography/mass spectrometry （GC-MS）, the basic nitrogen compounds have been separated and identified. Compared with the nitrogen content of the liquefied oil before and after separation, the basic nitrogen compounds account for more than half of all nitrogen compounds. The basic nitrogen compounds in the light liquefied oil are easily separated, and contain more types of basic nitrogen compounds. The results also show that there are many basic nitrogen compounds in liquefied oil, such as pyrrole, aniline, pyridine, quinoline and so on. However, there are fewer other types of basic nitrogen compounds.

Quantitative analysis of trace levels of β-ionone in water by liquid-liquidphase extraction-gas chromatography-mass spectrometry(LLE-GC-MS)

A simple and rapid technique based on liquid-liquid extraction coupled to gas chromatography-mass spectrometric detection(LLE-GC-MS) was developed for analysis of taste and odour compound β-ionone in water. Instrument parameters including programmed oven temperature, injection temperature and ion source temperature were evaluated and optimized. Effects of extraction time, ionic strength and p H on the detection efficiency were investigated and optimum conditions were 8 min of extraction time, without Na Cl addition at p H=9. Good linearity(R2=0.9997) was obtained when the linear range was 10-500 μg/L. The recoveries of β-ionone in ultrapure water and tap water samples were 88%-95% and 110%-114%, respectively. The relative standard deviations(RSD) were less than 10%. The method detection limit(MDL) and rejection quality level(RQL) were achieved at1.98 μg/L and 6.53 μg/L, respectively. LLE-GC-MS was demonstrated to be a rapid and convenient method for the determination ofβ-ionone in water samples.

Determination of the gas compositions for direct coal liquefaction by gas chromatography

Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and permanent gases, such as CO2, H2S, H2, and CO, for direct coal liquefaction has been realized. With four packed chromatographic columns, which are Hayesep-Q pre-column, Hayesep-Q column, molecular sieve 5A column and one PLOT A1203 S capillary column, the gas compositions for direct coal liquefaction are analyzed qualitatively and quantitatively by the external standard method. The determination method has such advantages as excellent separation, simple operation, rapid analysis and accurate results.

Research on Comparison of Gas Chromatography and Liquid Chromatogram Detecting Pesticide Residue

The existing methods of detecting pesticide residue include gas chromatography, high performance liquid chromatography, gas chromatograph-mass, liquid chromatograph-mass, capillary electrophoresis, radioimmunoassay, biosensor and rapid detection on the spot. The paper analyzes the comparison of gas chromatography and liquid chromatogram detecting pesticide residue, for achieving the development tendency and the future goal of analyzing pesticide residue.

现代卫生理化检验前瞻

现代卫生理化检验,是研究如何把现代分析化学理论、方法和技术,应用于卫生检验理论中,制定卫生理化检验分析程序,为所检样品的物理和化学组成的分析,提供可靠的方法和手段。1卫生理化检验与分析化学理论的关系1.1分析化学为卫生理化检验提供发展基础一个时期卫生理化检验技术发展到怎样的水平,

Urine metabonomic study for blood-replenishing mechanism of Angelica sinensis in a blood-deficient mouse model

This study aimed at determining the effects of Angelica sinensis(AS) on urinary metabolites in blood deficiency mice and exploring its replenishing blood mechanism. Gas chromatography–mass spectrometry(GC-MS) was applied to detect metabolites in the urine samples in different collection periods. Principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) were used to investigate the differences in metabolic profiles among control group(CG), blood deficiency model group(MG), AS groups, and Colla Corii Asini group(CCAG). The potential biomarkers were identified based on the variable importance in the projection(VIP), T-test, and National Institute of Standards and Technology(NIST) and mass spectra library. The metabolites were analyzed using metabolomics pathway analysis(Met PA) to build the metabolic pathways. Our results indicated that, on the seventh day, the levels of glucose, lactic acid, pyruvic acid, alanine, acetoacetic acid, and citric acid changed significantly in blood deficiency mice. However, these metabolic deviations came to closer to normal levels after AS intervention. The reversing blood-deficiency mechanism of AS might involve regulating synthesis and degradation of ketone bodies, Pyruvate metabolism, TCA cycle, and Glycolysis / Gluconeogenesis. In conclusion, metabonomics is a robust and promising means for the identification of biomarkers and elucidation of the mechanisms of a disease, thereby highlighting its importance in drug discovery.

Quantification of selected monohydroxy metabolites of polycyclic aromatic hydrocarbons in human urine

An analytical method was developed to quantitatively determine selected monohydroxy metabolites of polycyclic aromatic hydrocarbons(PAHs) in human urine. The procedure included enzymatic hydrolysis to cleave the conjugated metabolites, solid-phase microextraction enrichment, and gas chromatography-mass spectrometry analysis. The method proved to be sensitive enough to detect the selected PAH metabolites in human urine.