Direct Determination of 23 Kinds of Per-and Polyfluoroalkyl Substances in Crude Plant Extracts by Liquid Chromatography-Tandem Mass Spectrometry Coupled with Online Solid Phase Extraction / 分析化学

A new method for simultaneous determination of 23 kinds of per-and polyfluoroalkyl substances(PFASs)(13 kinds of perfluoro carboxylic acids,4 kinds of perfluoro sulfonic acids,and 6 kinds of new substitutes)in plant leaf tissue by ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)using automatic online solid phase extraction(SPE)to remove the matrix interference components in plant crude extracts was developed.The plant leaf samples were extracted twice with 1%formic acid-methanol solution,then evaporated to dry,redissolved with 70%methanol solution,and directly injected for analysis.After 23 kinds of target PFASs were purified automatically by online SPE with a WAX column,the six-way valve was switched to rinse PFASs onto an alkaline mobile phase system-compatible C18 analytical column.Then,the 23 kinds of target PFASs were separated within 16 min by gradient elution using a binary mobile phase system of methanol/water(Containing 0.4%ammonium hydroxide).Tandem mass spectrometry was performed in multiple reaction monitoring(MRM)mode for online detection of various PFASs,and quantification was carried out by internal standard method.The results of the method validation showed that satisfactory average recoveries of 23 kinds of PFASs in plant leaf samples(64.2%-125.5%),precision(relative standard deviations(RSDs)of 0.7%-12.8%),linearity(R2＞0.990),and sensitivity(the detection limits(S/N=3)were in the range of 0.02-0.50 μg/kg)were achieved.Finally,this method was used to detect PFASs in the marine green tide algae(Enteromorpha prolifera)and several tree leaves,and a total of 6 kinds of PFASs were detected,in which PFBA was the main contaminant.Compared with the reported offline SPE methods,the proposed online SPE technique significantly simplified the sample pretreatment process and provided an automatic,simple,and environment-friendly method for the routine monitoring of legacy and emerging PFASs in plant tissues.

Determination of glufosinate ammonium and three metabolites in urine by ultra performance liquid chromatography-tandem mass spectrometry / 环境与职业医学

Backgroud At present, there is no unified standard for the detection of glufosinate ammonium and three metabolites in urine, which affects the accurate assessment of occupational exposure risk to a certain extent. It is of great significance to establish a rapid and effective inspection method to ensure occupational safety and public health. Objective To establish an ultra performance liquid chromatography-tandem mass spectrometry for simultaneous determination of glufosinate ammonium and three metabolites in urine. Methods The effects of dilution solvents and dilution ratios on the response values of glufosinate ammonium and three metabolites were compared, and the retention capacities of solid phase extraction columns for targets as well as the effects of chromatographic columns and mobile phase systems on chromatographic peaks were analyzed. Samples were quantified by matrix effect matching external standard method. Accuracy of the method was evaluated by recovery rate of standard addition, and precision of the method was evaluated by relative standard deviation of intra-day and inter-day measurements. Urine samples of 30 health individuals were collected to evaluate the application of the method. Results The urine samples were diluted with 0.2 mL water and 0.6 mL acetonitrile, purified by HLB solid phase extraction columns, and separated by Dikma Polyamino HILIC columns, and gradient elution was carried out with 0.5 mmol·L−1 ammonium acetate and 0.1% ammonia water as mobile phase, which achieved a good peak shape and mass spectrum response. The linearities of the four target compounds were good in the range of 0.5-50 ng·mL−1, and the correlation coefficients (r) were all greater than 0.998. The detection limits were 0.56-2.86 μg·L−1, the quantification limits were 1.87-29.54 μg·L−1, and the recovery rates of standard addition ranged from 75.0% to 103.6%, The relative standard deviations of intra-batch and inter-batch were from 2.5% to 8.1% and from 4.3% to 9.3% respectively. The method was applied to detect 30 urine samples of subjects, and no target was detected. Conclusion The method is simple, rapid, sensitive, and accurate. It is suitable for the determination of glufosinate ammonium and its metabolites in human urine without derivatization.

Determination of eight high polar pesticide residues in vegetables and fruits by hydrophilic interaction liquid chromatography combined with ultra-performance liquid chromatography-tandem mass spectrometry / 环境与职业医学

Background The production and consumption of high polar pesticides in China are the largest in the world. Therefore, it is urgent to develop a method with fast analysis, large flux, and high accuracy to determine the residues of these pesticides in food. Objective To establish a method for the determination of eight highly polar pesticides [chlormequat, paraquat, difenzoquat, cyromazine, propamocarb, glyphosate, (aminomethyl)-phosphonic acid, and glufosinate] in vegetables and fruits by ultra-performance liquid chromatography-tandem mass spectrometry. Methods After comparing various types of hydrophilic interaction liquid chromatography (HILIC) columns, and optimizing pH value and buffer concentration of mobile phase, effective chromatographic retention and separation of selected eight pesticides were achieved. Based on the optimization of mass spectrometry under chromatographic conditions, a multiple reaction monitoring (MRM) channel of target compounds was established. In the sample pretreatment, through optimization of water content, extraction solvent, and purification method, a final MRM mode of ultra-performance liquid chromatography-tandem mass spectrometry was used for detection, and the isotope internal standard method was used for quantification. The accuracy and the precision of the method were evaluated using recovery and relative standard deviation. The established method was applied to detect 57 samples of retail vegetables and fruits to investigate the adaptability of the proposed method and the residual levels of selected high polar pesticides. Results For positive ion electrospray ionization (ESI+) detection, we chose Sielc Obelisc R as chromatographic column, and 20 mmol·L−1 ammonium formate solution (pH=3±0.05) and acetonitrile as mobile phase; for negative ion electrospray ionization (ESI−) detection, we chose Shodex Asahipak NH2P-50 2D as chromatographic column, and 5 mmol·L−1 ammonium acetate solution (pH=11±0.05) and acetonitrile as mobile phase to obtain good chromatographic separation and peak shape. Under the optimal conditions of sample water content standardization, using 2% acidified methanol as extraction solvent, and C18 dispersed solid phase extraction purification, the linearity ranges of five analytes (chlormequat, paraquat, difenzoquat, cyromazine, and propamocarb) and three analytes [glyphosate, (aminomethyl)phosphonic acid, and glufosinate] were 1.00-100 μg·L−1 and 5.00-500 μg·L−1 (both correlation coefficients>0.999) respectively, the detection limits were 0.002-0.010 mg·kg−1, and the limits of quantification (LOQ) were 0.005-0.025 mg·kg−1. At three spiked levels (LOQ, 2LOQ, and 5LOQ), the recoveries were in the range of 85.3%–113.2%, and the relative standard deviations were 1.5%–9.5% (n=6). Three target pesticides (chlormequat, cyromazine, and propamocarb) were detected in 57 samples of retail vegetables and fruits, and the residue of chlormequat in cowpea exceeded the maximum residue limit. Conclusion The established method of HILIC combined with ultra-performance liquid chromatography-tandem mass spectrometry and isotopic internal standard quantification has the characteristics of simplicity, stability, and easy operation, which is suitable for rapid screening and quantitative detection of selected eight high polar pesticide residues in large quantities of vegetables and fruits, and provides technical support for monitoring and risk assessment of high polar pesticide residues.

Detection of Phosphatidylethanol in Whole Blood by UPLC-MS/MS / 法医学杂志

OBJECTIVES@#To establish the ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method to detect ethanol metabolites phosphatidylethanol (PEth) in whole blood.@*METHODS@#An appropriate amount of aqueous solution including 1% formic acid was added to 100 μL whole blood, the protein was precipitated with acetone, centrifuged and the supernatant was purified and enriched by using Bond Elut Certify column. The eluent was redissolved with 1/1 isopropanol/acetonitrile (v/v) solution after nitrogen blowing and then tested by UPLC-MS/MS. Selective reaction monitoring scanning was carried out in negative ionization mode, and quantitative analysis was performed by external standard method.@*RESULTS@#PEth showed a linear relationship over the concentration range of 1-160 ng/mL in whole blood (r=0.999 9) with peak area. The detection limit was 0.2 ng/mL, the quantification limit was 1 ng/mL, the recovery rate was 97.43%-103.61%, the accuracy was 0.99%-1.77%, the intra-day precision was 0.4%-2.4%, and the inter-day precision was 1.1%-3.3%, and the matrix effect was 91.00%-99.55%. PEth was not detected in the in vitro blood samples supplemented with ethanol. PEth was detected positive in three drunk driving cases, and the concentration were 195.49, 83.67 and 876.12 ng/mL, respectively.@*CONCLUSIONS@#The established method has high sensitivity and specificity and the analysis results are accurate. It is suitable for the qualitative and quantitative analysis of PEth in whole blood.

Determination and Risk Assessment of Six Hepatotoxic Pyrrolizidine Alkaloids in Verbenae Herba / 中国实验方剂学杂志

Objective:To establish ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） for simultaneous determination of six hepatotoxic pyrrolizidine alkaloids in Verbenae Herba， and to carry out preliminary risk assessment according to the research results. Method:An ACQUITY UPLC HSS T3 column （2.1 mm×100 mm， 1.8 μm） was used for analysis with 0.05% formic acid and 2.5 mmol·L^-1 ammonium formate in water （A）-0.05% formic acid and 2.5 mmol·L^-1 ammonium formate in acetonitrile （B） as mobile phase for gradient elution （0-12 min， 3%-8%B； 12-25 min， 8%-15%B； 25-26 min， 15%-3%B； 26-30 min， 3%B）， the flow rate was 0.3 mL·min^-1， the column temperature was 40 ℃， and the injection volume was 1 μL. MS system was operated by electrospray ionization （ESI） in the positive ion mode with multiple reaction monitoring mode. MS parameters of triple quadrupole and six analytes were optimized for qualitative and quantitative analysis. According to the determination results， the risk assessment was carried out by using margin of exposure （MOE） combined with transfer rate of hot water extraction. Result:Based on the instrument precision， linear range， repeatability， stability， recovery and other methodological validations， the results were in conformity with relevant standards of quantitative analysis. The linear ranges of intermedine， lycopsamine， intermedine <italic>N</italic>-oxide， lycopsamine<italic> N</italic>-oxide， echimidine<italic> N</italic>-oxide and echimidine were good （<italic>r</italic>≥0.999 0） between peak area and mass concentration in the ranges of 0.984-49.20， 0.994-49.70， 1.012-50.60， 1.032-51.60， 1.004-50.20， 1.016-50.80 µg·L^-1， respectively. The average recoveries of these six analytes were 87.2%-94.2% with relative standard deviation （RSD）<4.0%. Their MOE values were >10 000. Conclusion:The UPLC-MS/MS established in this study is stable and feasible， which can provide scientific basis for the quality control and safety evaluation of hepatotoxic pyrrolizidine alkaloids in Verbenae Herba.

Difference Analysis of Pharmacokinetic Behavior of Active Ingredients in Wujiwan Between Normal Rats and Rats with Irritable Bowel Syndrome / 中国实验方剂学杂志

Objective:To establish an ultra-performance liquid chromatography-mass spectrometry （UPLC-MS/MS） for determining the plasma concentrations of 10 active ingredients in Wujiwan at different time points after oral administration， and to compare the pharmacokinetic characteristics between normal rats and rats with chronic visceral hypersensitive irritable bowel syndrome （CVH-IBS）. Method:CVH-IBS rat model was prepared by the neonatal rat colon percutaneous transluminal coronary angioplasty （PTCA） balloon stimulation method. After intragastric administration of Wujiwan （0.245 g·kg^-1）， blood was collected from the jugular vein at different time points， and the plasma concentrations of 10 active ingredients （berberine hydrochloride， palmatine hydrochloride， coptisine hydrochloride， jatrorrhizine hydrochloride， epiberberine， dihydroberberine， evodiamine， evodine， paeoniflorin， albiflorin） in Wujiwan was detected simultaneously by UPLC-MS/MS， the pharmacokinetic parameters of each component in normal rats and CVH-IBS rats were calculated. Result:The established UPLC-MS/MS could sensitively and accurately detect the plasma concentrations of 10 active ingredients of Wujiwan in rats. Compared with the normal group， the absorption rates of these 10 active ingredients of Wujiwan in the blood of CVH-IBS rats all decreased to a certain extent， and the peak time （<italic>t</italic>_max） was prolonged. Among them， the <italic>t</italic>_max of berberine hydrochloride and jatrorrhizine hydrochloride were significantly prolonged from 54 minute and 39 minute to 90 minute， respectively （<italic>P</italic><0.05， <italic>P</italic><0.01）. Area under the plasma concentration-time curve （AUC_0-<italic>_t</italic>） of each component increased， and evodiamine and paeoniflorin were significantly different （<italic>P</italic><0.05，<italic> P</italic><0.01）. The clearance rates （CL/<italic>F</italic>） of these 10 active ingredients were all decreased， among which berberine hydrochloride， palmatine hydrochloride and evodiamine had significant differences （<italic>P</italic><0.05， <italic>P</italic><0.01）. Conclusion:There are significant differences in the pharmacokinetic behavior of the active ingredients in Wujiwan between normal rats and CVH-IBS rats， which may be related to the destruction of microstructure of intestinal epithelial cells and the change of activity of liver enzymes under the pathological state of IBS.

Analysis on Content Differences of Artemisinin and Arteannuin B in Different Provenances of Artemisia annua Under Indoor Hydroponic Conditions / 中国实验方剂学杂志

Objective:To establish a method for the determination of artemisinin and arteannuin B in different <italic>Artemisia annua</italic> germplasms， compare the differences of the two compounds among different <italic>A. annua</italic> germplasm under the condition of hydroponic homogenization and explore the key factors affecting contents of principal compounds in different<italic> A. annua</italic> germplasms. Method:Seedlings from different <italic>A. annua</italic> germplasms were arranged randomly and fed in a hydroponic cultivation system. Contents of artemisinin and arteannuin B were detected by ultra performance liquid chromatography tandem mass spectrometry （UPLC-MS/MS） with multi-reaction monitoring mode and ACQUITY UPLC^® BEH C₁₈ column （2.1 mm×100 mm， 1.7 μm）， mobile phase was water-acetonitrile （95∶5， containing 0.1% formic acid， A） and acetonitrile-water （95∶5， containing 0.1% formic acid， B） for gradient elution （0-3.5 min， 25%-1%A； 3.5-3.6 min， 1%-25%A； 3.6-5.0 min， 25%A）， the flow rate was set at 0.4 mL·min^-1. The content differences of artemisinin and arteannuin B in different provenances of <italic>A. annua</italic> were detected and analyzed statistically. Result:The established method had high sensitivity and good separation. A significant difference of artemisinin and arteannuin B contents was observed in different germplasms under the same culture conditions， that is， under the constant temperature of 25 ℃ in hydroponics. The provenance with higher artemisinin content was Yunnan， and the content was 3 810.597 μg·g^-1. The highest strain of arteannuin B was Shanxi provenance germplasm with the content of 1 691.747 μg·g^-1. According to the content of artemisinin， the provenances were arranged as follows：Yunnan， Hainan， Hubei， Guangxi， Zhejiang， Shanxi， Beijing， Shandong， Heilongjiang， and Gansu province germplasms. Correlation analysis showed that there was a significant negative correlation between artemisinin content and latitude of <italic>A. annua</italic>， but there was no significant correlation between contents of artemisinin and arteannuin B and longitude. Conclusion:The contents of artemisinin and arteannuin B among different <italic>A. annua</italic> germplasms were significantly different under the same culture environment， and the dominant factors affecting biosynthesis and accumulation of artemisinin and arteannuin B in <italic>A. annua</italic> may be the genetic background， suggesting that germplasm improvement is the key factor to improve the medicinal quality of <italic>A. annua</italic> in subsequent cultivation.

Regulatory Effect of Polygala tenuifolia and Licorice-simmered P. tenuifolia on Learning and Memory， HPA Axis Function and Neurotransmitters in Rats with Heart-kidney Imbalance Insomnia / 中国实验方剂学杂志

Objective:To compare the regulatory effects of <italic>Polygala tenuifolia</italic> and licorice-simmered <italic>P. tenuifolia</italic> on learning and memory， hypothalamus-pituitary-adrenal axis （HPA axis） function and neurotransmitters in rats with heart-kidney imbalance insomnia. Method:The rat model of insomnia induced by multi-factor stimulation was established. After the model being made， the administration groups were given the extracts of <italic>P. tenuifolia</italic> and licorice-simmered <italic>P. tenuifolia</italic> by gavage （dose of 8 g·kg^-1·d^-1）， while the normal group and model group were given the same volume of normal saline for 7 days. Morris water maze was used to detect the changes of learning and memory ability of rats in each group. Enzyme-linked immunosorbent assay （ELISA） was used to determine the levels of corticotropin-releasing hormone （CRH）， adrenocorticotropic hormone （ACTH） and cortisol （CORT） in serum of rats from each group. The contents of 5-hydroxytryptamine （5-HT）， dopamine （DA）， <italic>γ</italic>-aminobutyric acid （GABA） and glutamic acid （Glu） in the hypothalamus of rats were determined simultaneously by ultra performance liquid chromatography tandem mass spectrometry （UPLC-MS/MS）. Result:Compared with the normal group， the spatial learning and memory ability of rats in the model group<italic> </italic>was decreased， the times and time of staying in target quadrant were significantly reduced （<italic>P<</italic>0.05， <italic>P<</italic>0.01）， the levels of CORT， CRH and ACTH in serum were significantly increased （<italic>P<</italic>0.01）， the contents of GABA， DA， 5-HT in hypothalamus tissue were significantly decreased （<italic>P<</italic>0.01）， and the content of Glu was significantly increased （<italic>P<</italic>0.01）. Compared with the model group， the spatial learning and memory ability of rats in the <italic>P. tenuifolia</italic> group and licorice-simmered <italic>P. tenuifolia </italic>group<italic> </italic>were increased， the times and time of staying in the target quadrant were significantly increased （<italic>P<</italic>0.05， <italic>P<</italic>0.01）， the levels of CORT， CRH and ACTH in serum were significantly decreased （<italic>P<</italic>0.05， <italic>P<</italic>0.01）， the contents of GABA， DA and 5-HT in hypothalamus tissue were significantly increased （<italic>P<</italic>0.05， <italic>P<</italic>0.01）， and the content of Glu was significantly decreased （<italic>P<</italic>0.05）. The recovery degree of each index in the licorice-simmered <italic>P. tenuifolia</italic> group was better than that in the <italic>P. tenuifolia</italic> group. Conclusion:Both <italic>P. tenuifolia</italic> and licorice-simmered <italic>P. tenuifolia</italic> can improve the learning and memory ability， improve the function of HPA axis， regulate the level of central neurotransmitters， and have the effect of calming the mind and improving the intelligence of rats with heart-kidney imbalance insomnia. The effect of licorice-simmered <italic>P. tenuifolia</italic> is better than that of <italic>P. tenuifolia.</italic>

\Quantitative determination of 10 illicit drugs in wastewater by liquid-liquid extraction-ultra performance liquid chromatography-tandem mass spectrometry / 中国药科大学学报

@#A deuterated internal standard quantitative analysis method based on liquid-liquid extraction-ultra performance liquid chromatography-tandem mass spectrometry (LLE-UPLC-MS/MS) for simultaneous determination of 10 illicit drugs in wastewater was established.Wastewater samples were concentrated by liquid-liquid extraction with dichloromethane: ethyl acetate (1∶1), and separated by a linear gradient of 0.1% formic acid-5 mmol/L ammonium formate aqueous solution and acetonitrile on a C18 column. The samples were then detected by ESI positive ion mode and multiple reaction monitoring mode (MRM) for quantitative analysis.All analytes had a good linear relationship (r ≥ 0.995 7) within the range of their respective standard curves; the limit of quantification was 1 ng/L (except amphetamine at 2.5 ng/L); the relative recovery rate ranged from 96.36% to 106.43%, and the intra- and inter-day precisions were less than 4.70%.This method is accurate, reliable and reproducible, and is suitable for the quantitative determination of 10 illicit drugs in wastewater.It is also suitable for wastewater with complex matrixes that affect solid phase extraction and enrichment.It provides a new analytical method for real-time monitoring of drug abuse.

Effect of Lidan Ruanjian Prescription on Lipid-lowering and Antiobesity andMetabolic Profile of Bile Acid / 中国实验方剂学杂志

Objective:To investigate the pharmacodynamics effects of antiobesity, lipid-lowering and the regulations of serum bile acid profiles of Lidan Ruanjian prescription (LDRJ) in obesity rats induced by high-fat diet. Method:The 42 rats were fed high-fat diet for 9 weeks to establish model of obese rats，24 rats were randomly divided into model group, high and low-dose LDRJ group (30,15 g·kg-1). Another 8 normal rats were selected as the normal group.The model group and normal group were given normal saline, and drug group was given the corresponding dose of drug for 4 weeks. Body weight, liver weight, white adipose tissue (WAT) weight were determined after administration medicine for 4 weeks. The bile flow of the rats was measured by bile duct intubation and fasting serum lipid levels of total cholesterol (TC), total triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) were detected by automatic biochemical analyzer. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) assay was used to test serum bile acid profile of each group rats. Result:Compared with the control group, the average body weight, liver weight, WAT weight of the model group were significantly increased (P<0.01), while the fasting serum TC, TG and LDL-C levels were elevated (P<0.05，P<0.01). The total bile secretion and bile flow at each test point within 2 h were decreased and the proportion of primary bile acids was decreased (P<0.05).The serum total bile acid content decreased significantly（P<0.01），levels of cholic acid (CA), deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), hyodeoxycholic acid (HDCA), taurocholic acid (TCA), taurodeoxycholic acid (TDCA), taurochenodeoxycholic acid (TCDCA), taurohyodeoxycholic acid (THDCA) and glycodeoxycholic acid (GDCA) were significantly reduced (P<0.05，P<0.01). Compare with model group, body weight, liver weight in high and low-dose LDRJ groups reduced significantly(P<0.05，P<0.01). Fasting serum TC, TG and LDL-C levels were decreased in high-dose group(P<0.05，P<0.01), so did as TG levels in low-dose group(P<0.05). The bile flow rate increased significantly in high-dose group 1~1.5 h after administration (P<0.05). All dose treatment groups increased the proportion of primary bile acids (P<0.05) and changed the bile acid profile, especially elevated the bile acid levels of TCA, DCA, glycocholic acid (GCA), GDCA in high-dose LDRJ group (P<0.05，P<0.01), while TCA and TCDCA in low-dose group (P<0.05). Conclusion:LDRJ has significant lipid-lowering and antiobesity effects and the mechanism might involve the increase of bile secretion, the stimulation of primary bile acid synthesis and the regulation of bile acid profile.

Determination of Lamotrigine, Olanzapine and Quetiapine in Human Plasma by Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry and Its Application in Therapeutic Drug Monitoring / 中国药学杂志

OBJECTIVE: To establish a highly sensitive and selective ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneous determination of the concentrations of lamotrigine, olanzapine and quetiapine in human plasma to provide guidance for clinical drug use. METHODS: The plasma samples were precipitated by methanol, voriconazole was used as internal standard, and then gradiently eluted by ACQUITY UPLC BEH C18 column (2.1 mm×50 mm, 1.7 μm) using mobile phase consisting of 0.1% formic acid solution and methanol. Multiple reaction monitoring (MRM) was conducted in ion detection mode using positive electrospray ionization source. RESULTS: The linear ranges of the calibration curves for lamotrigine, olanzapine and quetiapine in human plasma were 0.5-20 μg•mL-1, 2-200 and 10-1 000 ng•mL-1, respectively. The method had good matrix effect, extraction recovery, accuracy, precision and stability, and was successfully applied to analyze plasma samples of 45 patients. CONCLUSION: The UPLC-MS/MS method for determination of lamotrigine, olanzapine and quetiapine is proven to be a sensitive and reliable protocol for clinical therapeutic drug monitoring.

Determination of perfluorocarboxylic acids in fish by ultra performance liquid chromatography tandem mass spectrometry / 预防医学

Objective@#To develop the ultra performance liquid chromatography tandem mass spectrometry ( UPLC-MS/MS ) for the determination of perfluorocarboxylic acids ( PFCAs ) in fish.@*Methods@#The fish samples were extracted with tert-butyl methyl ether and purified by WAX columns. The WAX cartridges were rinsed with methanol and 25 mmol/L ammonium acetate, and the target compound residues were eluted with 0.5% ammonia methanol and then redissolved with 50% methanol aqueous solution after nitrogen blowing to nearly dry. Nine kinds of PFCAs were simultaneously quantified by UPLC-MS/MS with 1 mmol/L ammonium acetate-methanol solution as the mobile phase.@*Results@#The extraction was separated well in UPLC BEH C18 column. There were good linear correlations of nine kinds of PFCAs in the range of 1.0-200.0 ng/mL, with the coefficients all more than 0.99. The limits of detection and quantification were 0.06-0.19 μg/kg and 0.19-0.62 μg/kg, respectively. The recovery rates were 70.08%-117.24% at different spiked levels ( 5.0, 25.0, 50.0 μg/kg ), and the relative standard deviations were 2.31%-19.68%. @*Conclusion@#Through optimizing the pretreatment conditions, the mobile phase of liquid chromatography and the detection conditions of mass spectrometry, the UPLC-MS/MS could meet the monitoring requirements of PFCAs in fish.

Assay of unbound teicoplanin in human plasma by centrifugal ultrafiltration combined with ultra performance liquid chromatography-tandem mass spectrometry / 药学实践杂志

Objective To establish an assay method for unbound teicoplanin in plasma by centrifugal ultrafiltration combined with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods Protein was removed from plasma by a Centrifree® ultrafiltration device. The ultrafiltrate was injected to determine the unbound concentration of teicoplanin. EndeadvorsilTM C18 column (1.8 μm, 50 mm×2.1 mm) was used with gradient elution of acetonitrile and 0.02 mol/L ammonium acetate solution (containing 0.1% formic acid). The detection was performed on a triple-quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM)mode via electro spray ionization (ESI). Results The calibration curve of unbound teicoplanin in plasma was linear over the range of 0.10 to 8.00 μg/ml (r=0.999). The intra-assay precision and the inter-assay precision of samples didn't exceed 7.00%. The average relative recovery ratio was 97.9%, and the matrix effect factor was 0.97. The samples had good stability after being stored at room temperature for 10 h or at −20 ℃ for 15 days, and freeze-thawed 3 times (RSDs were all within 6.50%). Conclusion This method is convenient, fast, sensitive and accurate. It provided a basis for clinical development of teicoplanin unbound concentration monitoring.

Simultaneous determination of illicit drugs and their metabolites in wastewater by SPE-UPLC-MS/MS / 中国药科大学学报

@#A quantitative analysis method based on solid phase extraction-ultra performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS) for simultaneous determination of illicit drugs and their metabolites in wastewater was established. Samples filtered at pH of 2 and spiked with internal standard were loaded to Oasis Prime MCX cartridges for solid-phase extraction. The samples were washed with 4 mL of methanol and eluted with 4 mL of 5% ammonia in acetonitrile before reconstituting with 0.1% formic acid/water solution. ZORBAX Eclipse Plus C18 column was used for chromatography, and gradient elution was performed with 0.1% formic acid/water solution and acetonitrile as mobile phase. The samples were then detected by electrospray ionization (ESI) in positive ion mode, and multiple reaction monitoring mode (MRM) was adopted for quantitative analysis. All analytes had a good linear relationship (r ≥ 0.993 2) within the range of their respective standard curve; the limit of quantification was 1 ng/L (except amphetamine at 2.5 ng/L); the extraction recovery ranged from 82.13% to 99.96%; and the intra- and inter-day precisions were less than 9.43%. The method is accurate, reliable and reproducible, and is suitable for the quantitative determination of illicit drugs and their metabolites in wastewater and can provide an analytical method for real-time monitoring of drug abuse.

Determination of 13 Kinds of Sulfonylurea Herbicides Residues in Aquatic Products by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry / 分析化学

A sensitive method was proposed for determination of 13 kinds of sulfonylurea herbicides residues in aquatic products by solid phase extraction-ultra performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (SPE-UPLC-MS/MS). The edible part of carp, penaeus vannamei,crab,clam and sea cucumber were collected and homogenized. Analytes was extracted with ethyl acetate,and then cleaned up by MAX solid phase extraction column. Qualitation of the analytes was achieved with multiple reaction monitoring (MRM) and the external standard method was used for quantification. The 13 kinds of sulfonylurea herbicides showed good linearity in the concentration range of 5.0-100.0 μg/L respectively. The detection limits of the 13 analytes were 1.0 μg/kg, and the limit of quantification was 2.0 μg/kg. The average recoveries ranged from 75.4% to 118.3% with relative standard deviations from 2.1% to 14.5%. The 13 target analytes were not detected in grass carp,carp,sea cucumber,prawn,turbot of breeding and crabs from the market. The halosulfuron-methyl was detected in the edible tissues of crabs exposed to a 1.0 mg/L halosulfuron-methyl solution for 24,48 and 72 h,and the concentrations were 6.20, 12.1 and 16. 6 μg/kg respectively. The method can be stable and sensitive, and is applied to the determination of 13 kinds of sulfonylurea herbicides residues in aquatic products.

Determination of Pyraclostrobin and Its Metabolite Residues in Pollens and Honeys of Litchi By Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry / 分析化学

An effective method was developed for determination of pyraclostrobin and BF 500-3 residues in pollen and honey of litchi by QuEChERS coupled with ultra performance liquid chromatography-tandem mass spectrometry. The samples were extracted by acetonitrile and cleaned by primary secondary amine(PSA) and C18. In the positive ion mode and multi reaction monitoring mode,the analytes were quantified by the matrix matching standard solutions, and the pretreatment and mass spectrometry conditions were evaluated. The matrix matched standard solutions of pyraclostrobin and its metabolite BF 500-3 showed good linearities in the concentration range of 1-100 μg/L, with the correlation coefficients (R2) of 0.991-0.999. The average recoveries were 87.0%-97.8% with relative standard deviations of 1.3%-3.7%. The limit of detection (LOD) and the limit of quantification(LOQ) were 0.08-0.20 μg/kg and 0.20-0.50 μg/kg,respectively. The method was easy, quick and highly sensitive, and was suitable for quick determination of pyraclotrobin and its metabolites in pollen and honey of litchi.

Improve diagnostic performance of PCOS by measurements of testosterone and dehydcoepiandrosterone sulfate with ultra-performance liquid chromatography tandem mass spectrometry / 中华内分泌代谢杂志

Objective To compare ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) and chemiluminescence immunoassay(CLIA) measurement of human serum androgen levels in polycystic ovarian syndrome(PCOS). Methods 160 PCOS patients and 146 healthy subjects(control group) were recruited and their serum androgen levels——measurements of testosterone and dehydcoepiandrosterone sulfate (DHEA-S) were tested by UPLC-MS/MS and CLIA. The androgen results combined with body mass index(BMI) were analyzed by ROC curve. According to area under curve(AUC) calculated by SPSS, a better method will be selected to provide accurate test results for physicians. Results (1)AUC of DHEA-S tested by UPLC-MS/MS was significantly higher than the one tested by CLIA(P<0.01). There was no significant difference between the AUC of T tested by UPLC-MS/MS and the one tested by CLIA. (2)AUC of T combined with DHEA-S tested by HPLC was not only significantly higher than the AUC of two combined indicators tested by CLIA(P<0.01),but also significantly higher than the AUC of a single indicator——either T(P<0.01) or DHEA-S(P<0.01) tested by UPLC-MS/MS. (3)The AUC of T,DHEA-S combined with BMI tested by HPLC was not only significantly higher than the AUC of three combined indicators tested by CLIA(P<0.01),but also higher than the AUC of two combined indicators tested by UPLC-MS/MS(P<0.05). Conclusion T and DHEA-S tested by UPLC-MS/MS combined with BMI has a certain reference value in the diagnosis of PCOS.

Study on main components of water extract in Xiefei-Pingchuanling using UPLC-MS / 国际中医中药杂志

Objective To establish a Ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS) chromatographic method for Xiefei-Pingchuanling extract, and to analyze the main components of its water extract. Methods The UPLC-MS was adopted with acetonitrile -0.2% formic acid aqueous solution (gradient elution) as mobile phase at a flow rate of 0.8 ml/min, detection wave length at 254 nm, and column temperature was 30 ℃. Results Eighteen components were separated from Xiefei-Pingchuanling extract, and eight ingredients were identified, such as the ephedrine, pseudoephedrine hydrochloride, salvianolic acidB, rhein, aloeemodin, chrysophanol, physcionwere. Conclusions The UPLC-MS chromatographic method has the specialty of stability and repeatability, and it is suitable for analysis of Xiefei-Pingchuanling extract.

Simultaneous Determination of Plant Growth Regulators and Imidacloprid, Acetamiprid in Tea by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry / 分析化学

An efficient method for the analysis of multiclass plant growth regulators and pesticide (imidacloprid, acetamiprid) residues in tea was developed based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The samples were extracted with acetonitrile/formic acid (99∶1, V/V) solution, cleaned up with four sorbents including C18, strong anion exchanger (SAX), primary secondary amine (PSA) and anhydrous MgSO4. The compounds were separated on a HSS T3 column under positive/negative electrospray ionization mode, detected by scheduled multiple reaction monitoring (SMRM), and quantified by matrix-matched external standard curves. All pesticide residues showed good linearity in the concentration range of 1-200 μg/L (6-benzylaminopurine, paclobutrazol, uniconazole, forchlorfenuron, mepiquat chloride, imidacloprid, acetamiprid) or 5-1000 μg/L (2,4-dichlor-ophenoxyacetic acid, 4-chlorophenoxyacetic acid, indole-3-acetic acid, gibberellic acid, 1-naphthaleneacetic acid, indole-3-butyric acid) , with correlation coefficient (R2≥0.99). Limits of detection (LOD, S/N=3) and limits of quantitation (LOQ, S/N=10) were 0.18-9.68 μg/kg and 0.61-32.26 μg/kg, respectively. In addition, the spiked recoveries of tea samples were 73.1％-108.9％, and RSDs were 0.6％-8.0％. This method was applied to commercial samples, and all the detections were confirmed by acquiring transitions for each pesticide in the samples.

Simultaneous Determination of Seven Kinds of Fluorescent White Agents in Mushroom by QuEChERS-UltraPerformance Liquid Chromatography-Tandem Mass Spectrometry / 分析化学

A method based on QuEChERS coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the determination of seven kinds of fluorescent white agent residues in mushroom.After mixing with 10 mL of water, the sample was extracted with acidified acetonitrile, cleaned up by C18, primary secondary amine (PSA) and MgSO4.The separation of seven kinds of fluorescent white agents was performed on a C18 column with a gradient elution of acetonitrile and 0.1% acidified water as mobile phase.The target compounds were detected by electrospray ionization mass spectrometry in positive ion mode with multi reaction monitoring (MRM).Under the optimum conditions, the method had good linear relationship in the determination of the seven kinds of fluorescent white agents in a certain concentration range, with correlation coefficients greater than 0.991.Moreover, the limits of detection (S/N=3) were 0.05-0.4 μg/kg, the limits of quantitation (S/N=10) were 0.2-1.3 μg/kg, and the average recoveries for seven kinds of fluorescent white agent residues in msushroom were 70.1%-109.2%.In comparison with previous methods, the new procedure has characteristics of simple sample preparation and higher sensitivity.