[Objectives]To identify stained Schisandrae Chinensis Fructus in Lifei Tablets with carmine and acid red 73 as target substances.[Methods]High performance liquid chromatography(HPLC)and liquid chromatography tandem-ma...[Objectives]To identify stained Schisandrae Chinensis Fructus in Lifei Tablets with carmine and acid red 73 as target substances.[Methods]High performance liquid chromatography(HPLC)and liquid chromatography tandem-mass spectrometry(LC-MS/MS)was used to analyze the 70%methanol extract of the drug.The HPLC was equipped with an Inertstain-C_(18)(250 mm×4.6 mm,5μm)chromatographic column.The mobile phase was acetonitrile-5 mmol/L ammonium acetate solution,gradient elution:volume flow rate of 1.0 mL/min,column temperature of 30℃,detection wavelength of 509 nm.LC-MS/MS was equipped with a Waters-C_(18)(2.1 mm×150 mm,1.7μm)chromatographic column,the mobile phase was methanol-0.1%formic acid solution(containing 5 mmol/L ammonium acetate),gradient elution;the volume flow rate was 0.3 mL/min;ESI ion source,positive ion mode,full scan of primary and secondary mass spectrometry.[Results]Carmine and acid red 73 showed good linear relationship in HPLC and LC-MS/MS,with r greater than 0.995.The sample recovery and RSD values of HPLC and LC-MS/MS met the requirements.The RSD of the results determined by HPLC and LC-MS/MS was not greater than 5.0%.Both methods had good compatibility and could be used for the examination of carmine and acid red 73 in Lifei Tablets.[Conclusions]The method is reliable and reproducible and can be used to identify stained Schisandrae Chinensis Fructus in Lifei Tablets.展开更多
The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tande...The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for determining catecholamines and metanephrines in urine to replace an existing liquid chromatographic method using electrochemical detection.Urine samples were prepared using Oasis weak-cation-exchange cartridges.The eluate was analyzed on an Agilent ZORBAX Eclipse Plus Phenyl-Hexyl column in 3 min.Adrenaline,noradrenaline,dopamine,metanephrine,normetanephrine,and their deuterated internal standards were monitored in positive electrospray ionization mode by multiple reaction monitoring(MRM).No evidence of ion suppression was observed.The assay was linear up to 5μmol/L for adrenaline,5μmol/L for noradrenaline,6.1μmol/L for dopamine,5.6μmol/L for metanephrine,and 34.6μmol/L for normetanephrine,with lower limits of quantification of 5,5,12,6 and 7nmol/L,respectively.The intra-day and inter-day precisions for all analytes ranged from 0.59%to 4.64%and1.98%to 4.80%,respectively.External quality assurance samples were assayed and showed excellent agreement with the target values.This simple method provides an improved assay for determining urine catecholamines and metanephrines.展开更多
A simple,rapid and sensitive liquid chromatography-mass spectrometry(LC-MS)method was developed for the determination of salidroside in rat plasma and study of its pharmacokinetics after oral administration of suspe...A simple,rapid and sensitive liquid chromatography-mass spectrometry(LC-MS)method was developed for the determination of salidroside in rat plasma and study of its pharmacokinetics after oral administration of suspension of Erzhi Wan and Fructus Ligustri lucidi into Wistar rats.Plasma sample of 200 μL was extracted with acetic ether-isopropanol(2∶1)and the extraction was performed on a Kromasil C18 column(150 mm×4.6 mm,5 μm)with the mobile phase of methanol-water(41∶59,v/v)within a run time of 6.0 min.The analyte was monitored with positive electrospray ionization(ESI)by selected ion monitoring(SIM)mode.The target ions were m/z 323.05 for salidroside and m/z 411.05 for internal standard(IS)geniposide.A good linear relationship was obtained over the range of 5.0-500.0 ng/mL and the lower limit of quantification was 5.0 ng/mL.The validated method was successfully applied to the pharmacokinetic study of salidroside in rat plasma after oral administration of suspension of Erzhi Wan and Fructus Ligustri lucidi.展开更多
An accurate and sensitive method for the simultaneous determination of gibberellic acid(GA3), gibberellin A4(GA4) and gibberellin A7(GA7) residues in tomato paste was developed by coupling solid phase extraction...An accurate and sensitive method for the simultaneous determination of gibberellic acid(GA3), gibberellin A4(GA4) and gibberellin A7(GA7) residues in tomato paste was developed by coupling solid phase extraction to high performance liquid chromatography-tandem mass spectrometry(LC-MS/MS) with electrospray ionization based stable isotope dilution analysis(SIDA). The isotope labeled internal standard can compensate for the losses during the extraction and cleanup steps and for discrimination due to ion suppression. After extraction from methanol, hydrophile lipophilic balance(HLB) solid phase extraction(SPE) column was tested for the capacity of the cleanup of the tomato paste in compared with C18 SPE column which is the common way to the detection of GAs, and the former gained better result. Spiked experiments were performed in the non-contaminated tomato pastes and the recoveries of GA3, GA4 and GA7 were 42.6%―75.0% in external standard method(ESM) and 91.1%―103.8% in internal standard method(ISM) respectively. The validities of this method were investigated and good analytical performance for the three GAs was obtained, including low limits of method detection(2 ng/g for GA3 and GA4, 0.3 ng/g for GA7), excellent linear dynamic ranges(5―500 ng/g for GA3 and GA4, 1―100 ng/g for GA7) and good relative standard deviation ranges(4.8%―9.4% for the intra-day test and 3.5%―11.9% for the inter-day test).展开更多
Over the past decade, the use of hair specimens for the long-term detection of the alcohol biomarker ethyl glucuronide has been increasing in popularity and usage. We evaluated the usefulness of fingernail clippings a...Over the past decade, the use of hair specimens for the long-term detection of the alcohol biomarker ethyl glucuronide has been increasing in popularity and usage. We evaluated the usefulness of fingernail clippings as a suitable alterna-tive to hair for ethyl glucuronide detection. A liquid chromatography-tandem mass spectrometry method for the detection of ethyl glucuronide in fingernail clippings was fully validated and used to analyze the hair and/or fingernail specimens of 606 college-aged study participants. The limit of detection was 2 pg/mg, the limit of quantitation was 8 pg/mg and the method was linear from 8 to 2000 pg/mg. Intra- and inter-assay imprecision studies at three different concentrations (20, 40, 200 pg/mg) were all within 7.8% and all intra- and inter-assay bias studies at these levels were within 115.1% of target concentration. Ethyl glucuronide levels in fingernail (mean = 29.1 ± 55.6 pg/mg) were higher than ethyl glucuronide levels in hair (mean = 9.48 ± 22.3 pg/mg) and a correlation of the matched pairs was observed (r = 0.552, P < 0.01, n = 529). Evaluating each gender separately revealed that the correlation of male fingernail to male hair was large and significant (r = 0.782, P < 0.01, n = 195) while female hair to female fingernail was small yet sig-nificant (r = 0.249, P < 0.01, n = 334). The study results demonstrated that fingernail may be a suitable alternative to hair for ethyl glucuronide detection and may be the preferred sample type due to the lack of a gender bias.展开更多
A simple, rapid and sensitive liquid chromatography-tandem mass spectrometry(LC-MS/MS) for the determination of glycyrrhetic acid in human plasma with ginsenoside Rh2 as internal standard was developed and validated...A simple, rapid and sensitive liquid chromatography-tandem mass spectrometry(LC-MS/MS) for the determination of glycyrrhetic acid in human plasma with ginsenoside Rh2 as internal standard was developed and validated. The plasma samples were prepared via liquid-liquid extraction with ethyl acetate. Chromatographic separation was accomplished on a Venusil MP-C18(50 mm×2.1 mm, 5 μm i.d.) column at 25 °C. The mobile phase consisted of acetonitrile/5 mmol?L-1 ammonium acetate(10:90, volume ratio) at a flow rate of 0.4 mL/min. Negative electrospray ionization was utilized as the ionization source. Glycyrrhetic acid and internal standard were determined via the mutiple reaction monitoring of precursor→production ion transitions at m/z 469→425, 409 and m/z 621→161, respectively. Each sample was chromatographed within 2.5 min. The lower limit of quantification was 0.50 ng/mL for 200 μL of plasma sample and the linear range was from 0.50 ng/mL to 800 ng/mL. The intra- and inter-day precisions were less than 8.76% in terms of relative standard deviation(RSD), and the accuracy was within a range of -3.25%-1.32% in terms of relative error(RE). The method was successfully applied to the pharmacokinetic studies of glycyrrhetic acid in healthy male Chinese volunteers after a single oral administration of 75 mg of glycyrrhizin.展开更多
The major objective of this study was to determine the effect of corn straw or mixed diet on the small molecule metabolites of liver and milk production of healthy Chinese Holstein cows during lactation.In this study,...The major objective of this study was to determine the effect of corn straw or mixed diet on the small molecule metabolites of liver and milk production of healthy Chinese Holstein cows during lactation.In this study,metabolomic methods based on ultra performance liquid chromatography-mass spectrometry(LC-MS)were used to study the liver metabolites of dairy cows fed on corn straw diet or mixed diet.Ten healthy Chinese Holstein cows were randomly assigned to two groups,under the same management condition,fed different diets respectively,corn straw group(CS)or a mixture of alfalfa hay and Chinese wild rye hay mixed forage group(MF).All the cows were fed for 8 weeks and recorded body weight,dry matter intake,body condition score,fat,protein,lactose,milk yield and the total solids.Livers were sampled from each cow through a liver puncture needle for analysis of a significant difference in small molecule metabolites in cow liver samples from the two different diets.The results suggested that different diet types had significant effects on liver metabolism and milk components in dairy cows.The contents of milk fat,the total solids,milk protein,lactose,dry matter intake(DMI),milk yield,milk protein(%),lactose(%)and milk fat(%)of the corn straw group were significantly lower than those of the mixed forage group(p<0.05);the contents of phosphatidylcholine(PC),histidine,hypoxanthine and mridine in liver tissues of the corn straw group were significantly lower than those in the mixed forage group(p<0.05);acetylcarnitine,uric acid,triacylglycerol(TG),acetal phosphatidylcholine(plasmenyl-PC),acetalphosphatidylethanolamine(plasmenyl-PE)and sphingomyelin(SM)of the corn straw group were significantly higher than those in the mixed forage group(p<0.05).In summary,cows fed on mixed forage diet significantly improved milk yield and lactation performance clearly.展开更多
The purpose of this study was to characterize mulberry leaf instant tea(MLIT)powder prepared from the'Longsang No.1'(Morus abla L.cv.Longsang 1)mulberry leaves in Heilongjiang Province(China)and assess its obe...The purpose of this study was to characterize mulberry leaf instant tea(MLIT)powder prepared from the'Longsang No.1'(Morus abla L.cv.Longsang 1)mulberry leaves in Heilongjiang Province(China)and assess its obesity-preventing/relieving effects.A total of 174 compounds including quercetin,chlorogenic acid,1-deoxyecomycin(1-DNJ)related to antihyperlipidemia effects were identified from the MLIT powder.MLIT treatment reversed the Lee's index,fat coefficient,and serum biochemical parameters in both the obesity relieving and obesity preventing mice fed with high-fat diet.In the obesity relieving experiment,the relative abundance of Desulfovibrio in mouse feces decreased after both 0.5%and 1%MLIT treatments.In obesity preventing experiments,mouse with different amount of MLIT treatments showed increased relative abundance of Akkermansia,Bifidobacterium and Lactobacillus,while Deferribacteres,Desulfobacterota decreased.The beneficial bacteria in the intestinal tract of mice treated with MLIT increased.This study proved that MLIT had antihyperlipidemia potential via modulating intestinal microbiota in mice.展开更多
Glioblastoma Multiforme (GBM) represents one of the most aggressive and metastatic brain tumors, with a dismal success rate of less than three percent after five years, particularly in tumors with active immune checkp...Glioblastoma Multiforme (GBM) represents one of the most aggressive and metastatic brain tumors, with a dismal success rate of less than three percent after five years, particularly in tumors with active immune checkpoints. This necessitates the development of targeted endogenous agents for precise GBM treatment. Previous experiments utilizing Chemovar Specific Cannabis Extractions (CSCEs), fractionated with polar solvents and quantified using Liquid and Gas Column Chromatography combined with Mass Spectrometry (LC/GCMS), have shown reduced viability and motility in human GBM cell lines. However, the complexity of the botanical substance has hindered the personalization of standard cannabis medicines for GBM due to unknown synergistic effects of multiple compounds. To address this limitation, our study focuses on exposing AM251 cells to chemovar fractions extracted using a non-polar solvent, thereby isolating a broader spectrum of constituents. By employing LC/GCMS in conjunction with Nuclear Magnetic Resonance (NMR), we have identified and quantified nine* compounds present in the non-polar CSCE that exhibit significant efficacy (0.1 μM) in inducing cytotoxicity* in GBM tumor cells. Conversely, the polar fraction in our experiment did not demonstrate efficacy against UM251 cells. The quantification of individual compounds within a cannabis extraction that selectively induces cell death in brain tumors holds promise for guiding future research and facilitating the development of a standardized CSCE for GBM therapy.展开更多
Surfactant is widely used in the industry,and its determination is important in both performance and quality control consideration.A liquid chromatography coupling mass spectrometry(LC-MS)method was established for an...Surfactant is widely used in the industry,and its determination is important in both performance and quality control consideration.A liquid chromatography coupling mass spectrometry(LC-MS)method was established for analyzing surfactants in lubricant.Three surfactants,including polyoxyethylene(9)nonyl phenyl ether,polyoxyethylene(10)decanamine ether,and polyoxyethylene(5)oleylamine ether were identified.展开更多
Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments,...Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments, and fish muscles were developed. In water samples, drugs were extracted with solid-phase extraction (SPE) by passing 1000 mL of water through hydrophilic lipophilic balanced (HLB) SPE cartridges. Sediment samples were solvent-extracted, followed by tandem SPE (strong anion exchange (SAX) + HLB) clean-ups. Fish muscles were extracted by a mixture of acetonitrile and citric buffer (80:20, v/v) solution, and cleaned by SPE. Liquid chromatography-tandem mass spectrometry (LC-MS/ MS) with multiple reaction monitoring (MRM) detection was employed to quantify all compounds. The recoveries for the antibiotics in the spiked water, sediment, and fish samples were 60.2%-95.8%, 48.1%-105.3%, and 59.8%- 103.4%, respectively. The methods were applied to samples taken from Dianchi Lake, China. It showed that concentrations of the detected antibiotics ranged from limits of quantification (LOQ) to 713.6 ng- L1 (ofloxacin) in surface water and from less than LOQ to 344.8 μg·kg-1 (sulphamethoxazole) in sediments. The number of detected antibiotics and the overall antibiotic concentrations were higher in the urban area than the rural area, indicating the probable role of livestock and human activities as important sources of antibiotic contamination. In fish muscles, the concentration of norfioxacin was the highest (up to 38.5 μg·kg-1), but tetracyclines and macrolides were relatively low. Results showed that the methods were rapid and sensitive, and capable of determining several classes of antibiotics from each of the water, sediment, and fish matrices in a single run.展开更多
To establish HPLC electrospray ionization mass spectrometry (HPLC-ESI MS) method for determination of osthole in food additive.The samples were dipped in methanol overnight and extracted with it by ultrasonic instrume...To establish HPLC electrospray ionization mass spectrometry (HPLC-ESI MS) method for determination of osthole in food additive.The samples were dipped in methanol overnight and extracted with it by ultrasonic instrument,then the supernatant was send to sampler for detection.Sample was chromatographed using 0.4%HAc solution-MeOH (35:65,by volume) mobile phase on an Xterra MS C18 column.Analyte determination was performed by ESI MS/MS in the multiple reaction monitoring(MRM)mode.The established method of LC-MS/MS determining the concentration of osthole in food additive has the characteristic of strong specificity,high sensitivity and good reproducibility.The linear range of papaverine was 0.001-10 μg/mL,method recovery was 97.42%,RSD was 8.37%,the limit of detection was 1 ng/mL and the limit of quantitation was 0.001 μg/mL.展开更多
A total of 133 shellfish samples were collected in seven cities of Shandong Province,China,from May to October,2019.The domoic acid(DA)concentrations were determined by liquid chromatographytandem mass spectrometry(LC...A total of 133 shellfish samples were collected in seven cities of Shandong Province,China,from May to October,2019.The domoic acid(DA)concentrations were determined by liquid chromatographytandem mass spectrometry(LC-MS/MS),and their distribution characteristics were investigated.DA concentration was detected high in over 1/3(36.1%)of the samples of four kinds of shellfish in all three seasons in range from 0 to 102μg/kg.The highest DA concentrations were 102,101,36.7,and 10.2μg/kg in Crassostrea gigas,Chlamys farreri,Mactra veneriformis,and Mytilus edulis,respectively.Geographically,Yantai(22.0μg/kg)and Weihai(16.9μg/kg)showed relatively high concentrations of DA,whereas Rizhao and Dongying presented only 0.85-and 1.76-μg/kg DA,respectively.DA concentrations in the shellfish samples were strongly related to seasonal changes,being significantly higher in autumn and summer than that in spring.The DA risk exposure assessments indicate that dietary seafood consumption did not pose a health threat to general human population.In addition,three isomers(isoA,isoD,isoE)and 5′-epimer DA were detected in 3.00%-15.80%of the shellfish samples.This study is the first to observe DA and its isomers in shellfish samples of Shandong Province.The results demonstrate that DA contamination is very common and should be continuously monitored.展开更多
A reliable liquid chromatography-tandem mass spectrometric(LC-MS/MS) method was developed and va- lidated for the simultaneous determination of vancomycin and voriconazole in human plasma. The analytes and internal ...A reliable liquid chromatography-tandem mass spectrometric(LC-MS/MS) method was developed and va- lidated for the simultaneous determination of vancomycin and voriconazole in human plasma. The analytes and internal standard 10-hydroxycarbazepine were separated at a flow rate of 0.9 mL/min using a Zorbax SB-C18 column (50 min×4.6 mm, 2.7 μm). Positive ion electrospray ionization was used to detect vancomycin, voriconazole and intrenal standard(IS) 10-hydroxycarbazepine followed by multiple reaction monitoring(MRM) of the transition at m/z 725.5→144.2, 350.3→281.0 and 253.1→208.0, respectively. The total run time for both vancomycin and voriconazole samples was 5 min; 0.30μg/mL was the lower limit of quantification. The precision of intraday and interday was no more than 12.4%. The method was successfully and resoundingly applied in therapeutic drug monitoring of 156 patients treated with vancomycin and voriconazole.展开更多
Hemipteran insects are the most devastating pest for different crops of high economic value. Colocasia esculenta tuber agglutinin (CEA), a mannose binding monocot lectin from araceae family was previously reported by ...Hemipteran insects are the most devastating pest for different crops of high economic value. Colocasia esculenta tuber agglutinin (CEA), a mannose binding monocot lectin from araceae family was previously reported by the present group to be effective against some members of this class of pests. In the present study, efficacy of this potent lectin has been extended to cotton aphid (Aphis gossypii) which is becoming a highly damaging pest of cotton in recent days. Because, like other aphids, A. gossypii not only extracts the phloem fluid but also transmit disease causing viruses and add to the high degree of yield loss. Efficacy of the lectin on cotton aphid as well as other hemipteran insects prompted us further to clone the protein coding gene. Very little sequence information of this gene was available in the database. Hence, attempt had been made to study the protein through liquid chromatography-tandem mass spectrometry (LC-MS/MS) to have the detailed peptide information. On the basis of the peptide homology information obtained from LC-MS/MS the complete coding sequence of CEA was determined. The coding sequence corresponding to CEA was cloned further using primers designed on the basis of above information and genome walk technology for its potential utilisation in insect management programme.展开更多
Astilbin is a potential immunosuppressive agent with minor cytotoxicity. Its oral bioavailability is supposed to be rather low and therefore a sensitive analytical method is required for its pharmacokinetic study afte...Astilbin is a potential immunosuppressive agent with minor cytotoxicity. Its oral bioavailability is supposed to be rather low and therefore a sensitive analytical method is required for its pharmacokinetic study after oral administration. A simple, sensitive and rapid liquid chromatography-tandem mass spectrometry(LC-MS/MS) method was developed and validated for the determination of astilbin in rat plasma. Plasma samples were subjected to liquid-liquid extraction with ethyl acetate and separated by reversed phase high performance liquid chromatography(HPLC) with methanol-0.01%(volume fraction) formic acid(50:50, volume ratio) as mobile phase. Quantitive determination was achieved on negative LC-MS/MS by a multiple reaction moitoring method with transitions m/z 449.1→150.9(quantifier) and m/z 449.1→284.9(qualifier) for astilbin and m/z 128.9→42.0 for internal standard(IS). A lower limit of quantification(LLOQ) of ng/mL was achieved within a short cycle time of 3.4 min. The method was successfully applied to a pharmacokinetic study involving oral and intravenous administrations of 6 mg/kg astilbin to six rats.展开更多
A rapid and sensitive liquid chromatography-tandem mass spectrometry(LC-MS/MS) method for the de- termination of cefotetan in human plasma was developed and validated. After the protein precipitation of sample with ...A rapid and sensitive liquid chromatography-tandem mass spectrometry(LC-MS/MS) method for the de- termination of cefotetan in human plasma was developed and validated. After the protein precipitation of sample with acetonitrile, the analyte and internal standard(IS), tramadol, were separated on a Zorbax XDB C8 column using ace- tonitrile/1%(volume fraction) formic acid(volume ratio 35:65, pH=2.5) as mobile phase at a flow rate of 1.0 mL/min with a 1 : 1 split. The detection was performed by electrospray ionization with positive ion mode, followed by multiple reaction monitoring of the transitions for cefotetan at m/z 576.3→460.2(quantifier) and m/z 576.3→432.2(qualifier) and for IS at m/z 264.1→58.1. Cefotetan and IS were eluted at 1.86 and 1.87 rain, respectively. The assay was linear over the concentration range of 0.1-100 gg/mL for 20 μL of human plasma only with intra- and inter-day preci- sions(expressed as the relative standard deviation) of less than 6.62% and accuracies(as relative error) of +1.31%. The method was applied to the pharmacokinetic study of a l-h intravenous infusion of 1.0 g of cefotetan disodium for human volunteers(n=6).展开更多
Migraine is an episodic neurological disorder and the second most disabling disease with unclear pathogenesis.Since dietary adjustment and probiotics supplement can improve the symptoms of migraine,the intestinal flor...Migraine is an episodic neurological disorder and the second most disabling disease with unclear pathogenesis.Since dietary adjustment and probiotics supplement can improve the symptoms of migraine,the intestinal flora metabolites of bile acids(BAs)attract attentions in this work.21 BAs,including cholic acid(CA),chenodeoxycholic acid(CDCA),deoxycholic acid(DCA),lithocholic acid(LCA),ursodeoxycholic acid(UDCA),hyocholic acid(HCA),hyodeoxycholic acid(HDCA)and their glycine-and taurine-conjugated species,were compared in serum of migraine patients and healthy controls using liquid chromatography-tandem mass spectrometry(LC-MS/MS),which is the first study about the correlation between BAs and migraine.Two secondary BAs,DCA and LCA as well as their glycine-and taurine-conjugated forms,were demonstrated with significant difference between male patients and male controls,while no obvious difference was found in the two female groups.The result indicated that the variation of BAs might be gender-related when referred to migraine,which would emphasize the importance of gender-stratified analysis for the disease with varying morbidity in male and female.Five differential metabolites may serve as potential serum biomarkers for the male migraine patients,providing a new sight for the understanding and biomarker exploring of the migraine in male.展开更多
基金Supported by Chongqing Pharmaceutical Research Project of Chongqing Drug Administration and Chongqing Science and Technology Bureau(Yu Yao Jian[2021]30)。
文摘[Objectives]To identify stained Schisandrae Chinensis Fructus in Lifei Tablets with carmine and acid red 73 as target substances.[Methods]High performance liquid chromatography(HPLC)and liquid chromatography tandem-mass spectrometry(LC-MS/MS)was used to analyze the 70%methanol extract of the drug.The HPLC was equipped with an Inertstain-C_(18)(250 mm×4.6 mm,5μm)chromatographic column.The mobile phase was acetonitrile-5 mmol/L ammonium acetate solution,gradient elution:volume flow rate of 1.0 mL/min,column temperature of 30℃,detection wavelength of 509 nm.LC-MS/MS was equipped with a Waters-C_(18)(2.1 mm×150 mm,1.7μm)chromatographic column,the mobile phase was methanol-0.1%formic acid solution(containing 5 mmol/L ammonium acetate),gradient elution;the volume flow rate was 0.3 mL/min;ESI ion source,positive ion mode,full scan of primary and secondary mass spectrometry.[Results]Carmine and acid red 73 showed good linear relationship in HPLC and LC-MS/MS,with r greater than 0.995.The sample recovery and RSD values of HPLC and LC-MS/MS met the requirements.The RSD of the results determined by HPLC and LC-MS/MS was not greater than 5.0%.Both methods had good compatibility and could be used for the examination of carmine and acid red 73 in Lifei Tablets.[Conclusions]The method is reliable and reproducible and can be used to identify stained Schisandrae Chinensis Fructus in Lifei Tablets.
文摘The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for determining catecholamines and metanephrines in urine to replace an existing liquid chromatographic method using electrochemical detection.Urine samples were prepared using Oasis weak-cation-exchange cartridges.The eluate was analyzed on an Agilent ZORBAX Eclipse Plus Phenyl-Hexyl column in 3 min.Adrenaline,noradrenaline,dopamine,metanephrine,normetanephrine,and their deuterated internal standards were monitored in positive electrospray ionization mode by multiple reaction monitoring(MRM).No evidence of ion suppression was observed.The assay was linear up to 5μmol/L for adrenaline,5μmol/L for noradrenaline,6.1μmol/L for dopamine,5.6μmol/L for metanephrine,and 34.6μmol/L for normetanephrine,with lower limits of quantification of 5,5,12,6 and 7nmol/L,respectively.The intra-day and inter-day precisions for all analytes ranged from 0.59%to 4.64%and1.98%to 4.80%,respectively.External quality assurance samples were assayed and showed excellent agreement with the target values.This simple method provides an improved assay for determining urine catecholamines and metanephrines.
文摘A simple,rapid and sensitive liquid chromatography-mass spectrometry(LC-MS)method was developed for the determination of salidroside in rat plasma and study of its pharmacokinetics after oral administration of suspension of Erzhi Wan and Fructus Ligustri lucidi into Wistar rats.Plasma sample of 200 μL was extracted with acetic ether-isopropanol(2∶1)and the extraction was performed on a Kromasil C18 column(150 mm×4.6 mm,5 μm)with the mobile phase of methanol-water(41∶59,v/v)within a run time of 6.0 min.The analyte was monitored with positive electrospray ionization(ESI)by selected ion monitoring(SIM)mode.The target ions were m/z 323.05 for salidroside and m/z 411.05 for internal standard(IS)geniposide.A good linear relationship was obtained over the range of 5.0-500.0 ng/mL and the lower limit of quantification was 5.0 ng/mL.The validated method was successfully applied to the pharmacokinetic study of salidroside in rat plasma after oral administration of suspension of Erzhi Wan and Fructus Ligustri lucidi.
基金Supported by the Project of Chinese Academy of Inspection and Quanrantine(No.2010JK001)the Project of Xinjiang Entry-exit Inspection and Quarantine Bureau, China(No.2010XK0033)
文摘An accurate and sensitive method for the simultaneous determination of gibberellic acid(GA3), gibberellin A4(GA4) and gibberellin A7(GA7) residues in tomato paste was developed by coupling solid phase extraction to high performance liquid chromatography-tandem mass spectrometry(LC-MS/MS) with electrospray ionization based stable isotope dilution analysis(SIDA). The isotope labeled internal standard can compensate for the losses during the extraction and cleanup steps and for discrimination due to ion suppression. After extraction from methanol, hydrophile lipophilic balance(HLB) solid phase extraction(SPE) column was tested for the capacity of the cleanup of the tomato paste in compared with C18 SPE column which is the common way to the detection of GAs, and the former gained better result. Spiked experiments were performed in the non-contaminated tomato pastes and the recoveries of GA3, GA4 and GA7 were 42.6%―75.0% in external standard method(ESM) and 91.1%―103.8% in internal standard method(ISM) respectively. The validities of this method were investigated and good analytical performance for the three GAs was obtained, including low limits of method detection(2 ng/g for GA3 and GA4, 0.3 ng/g for GA7), excellent linear dynamic ranges(5―500 ng/g for GA3 and GA4, 1―100 ng/g for GA7) and good relative standard deviation ranges(4.8%―9.4% for the intra-day test and 3.5%―11.9% for the inter-day test).
文摘Over the past decade, the use of hair specimens for the long-term detection of the alcohol biomarker ethyl glucuronide has been increasing in popularity and usage. We evaluated the usefulness of fingernail clippings as a suitable alterna-tive to hair for ethyl glucuronide detection. A liquid chromatography-tandem mass spectrometry method for the detection of ethyl glucuronide in fingernail clippings was fully validated and used to analyze the hair and/or fingernail specimens of 606 college-aged study participants. The limit of detection was 2 pg/mg, the limit of quantitation was 8 pg/mg and the method was linear from 8 to 2000 pg/mg. Intra- and inter-assay imprecision studies at three different concentrations (20, 40, 200 pg/mg) were all within 7.8% and all intra- and inter-assay bias studies at these levels were within 115.1% of target concentration. Ethyl glucuronide levels in fingernail (mean = 29.1 ± 55.6 pg/mg) were higher than ethyl glucuronide levels in hair (mean = 9.48 ± 22.3 pg/mg) and a correlation of the matched pairs was observed (r = 0.552, P < 0.01, n = 529). Evaluating each gender separately revealed that the correlation of male fingernail to male hair was large and significant (r = 0.782, P < 0.01, n = 195) while female hair to female fingernail was small yet sig-nificant (r = 0.249, P < 0.01, n = 334). The study results demonstrated that fingernail may be a suitable alternative to hair for ethyl glucuronide detection and may be the preferred sample type due to the lack of a gender bias.
基金Supported by the Xinjiang Vurge Autonomous Region(China) Tackle Key Problems in Science and Technology and Plan of Emphasis Project(No.200733146-4)
文摘A simple, rapid and sensitive liquid chromatography-tandem mass spectrometry(LC-MS/MS) for the determination of glycyrrhetic acid in human plasma with ginsenoside Rh2 as internal standard was developed and validated. The plasma samples were prepared via liquid-liquid extraction with ethyl acetate. Chromatographic separation was accomplished on a Venusil MP-C18(50 mm×2.1 mm, 5 μm i.d.) column at 25 °C. The mobile phase consisted of acetonitrile/5 mmol?L-1 ammonium acetate(10:90, volume ratio) at a flow rate of 0.4 mL/min. Negative electrospray ionization was utilized as the ionization source. Glycyrrhetic acid and internal standard were determined via the mutiple reaction monitoring of precursor→production ion transitions at m/z 469→425, 409 and m/z 621→161, respectively. Each sample was chromatographed within 2.5 min. The lower limit of quantification was 0.50 ng/mL for 200 μL of plasma sample and the linear range was from 0.50 ng/mL to 800 ng/mL. The intra- and inter-day precisions were less than 8.76% in terms of relative standard deviation(RSD), and the accuracy was within a range of -3.25%-1.32% in terms of relative error(RE). The method was successfully applied to the pharmacokinetic studies of glycyrrhetic acid in healthy male Chinese volunteers after a single oral administration of 75 mg of glycyrrhizin.
基金Supported by the National Natural Science Foundation of China(31101784)Funds for Young Researchers from Northeast Agricultural University(14QC43)。
文摘The major objective of this study was to determine the effect of corn straw or mixed diet on the small molecule metabolites of liver and milk production of healthy Chinese Holstein cows during lactation.In this study,metabolomic methods based on ultra performance liquid chromatography-mass spectrometry(LC-MS)were used to study the liver metabolites of dairy cows fed on corn straw diet or mixed diet.Ten healthy Chinese Holstein cows were randomly assigned to two groups,under the same management condition,fed different diets respectively,corn straw group(CS)or a mixture of alfalfa hay and Chinese wild rye hay mixed forage group(MF).All the cows were fed for 8 weeks and recorded body weight,dry matter intake,body condition score,fat,protein,lactose,milk yield and the total solids.Livers were sampled from each cow through a liver puncture needle for analysis of a significant difference in small molecule metabolites in cow liver samples from the two different diets.The results suggested that different diet types had significant effects on liver metabolism and milk components in dairy cows.The contents of milk fat,the total solids,milk protein,lactose,dry matter intake(DMI),milk yield,milk protein(%),lactose(%)and milk fat(%)of the corn straw group were significantly lower than those of the mixed forage group(p<0.05);the contents of phosphatidylcholine(PC),histidine,hypoxanthine and mridine in liver tissues of the corn straw group were significantly lower than those in the mixed forage group(p<0.05);acetylcarnitine,uric acid,triacylglycerol(TG),acetal phosphatidylcholine(plasmenyl-PC),acetalphosphatidylethanolamine(plasmenyl-PE)and sphingomyelin(SM)of the corn straw group were significantly higher than those in the mixed forage group(p<0.05).In summary,cows fed on mixed forage diet significantly improved milk yield and lactation performance clearly.
基金supported by the Natural Science Foundation of Heilongjiang Province (LH2021C075)Key Laboratory of Functional Inorganic Material Chemistry (Heilongjiang University),Ministry of Education。
文摘The purpose of this study was to characterize mulberry leaf instant tea(MLIT)powder prepared from the'Longsang No.1'(Morus abla L.cv.Longsang 1)mulberry leaves in Heilongjiang Province(China)and assess its obesity-preventing/relieving effects.A total of 174 compounds including quercetin,chlorogenic acid,1-deoxyecomycin(1-DNJ)related to antihyperlipidemia effects were identified from the MLIT powder.MLIT treatment reversed the Lee's index,fat coefficient,and serum biochemical parameters in both the obesity relieving and obesity preventing mice fed with high-fat diet.In the obesity relieving experiment,the relative abundance of Desulfovibrio in mouse feces decreased after both 0.5%and 1%MLIT treatments.In obesity preventing experiments,mouse with different amount of MLIT treatments showed increased relative abundance of Akkermansia,Bifidobacterium and Lactobacillus,while Deferribacteres,Desulfobacterota decreased.The beneficial bacteria in the intestinal tract of mice treated with MLIT increased.This study proved that MLIT had antihyperlipidemia potential via modulating intestinal microbiota in mice.
文摘Glioblastoma Multiforme (GBM) represents one of the most aggressive and metastatic brain tumors, with a dismal success rate of less than three percent after five years, particularly in tumors with active immune checkpoints. This necessitates the development of targeted endogenous agents for precise GBM treatment. Previous experiments utilizing Chemovar Specific Cannabis Extractions (CSCEs), fractionated with polar solvents and quantified using Liquid and Gas Column Chromatography combined with Mass Spectrometry (LC/GCMS), have shown reduced viability and motility in human GBM cell lines. However, the complexity of the botanical substance has hindered the personalization of standard cannabis medicines for GBM due to unknown synergistic effects of multiple compounds. To address this limitation, our study focuses on exposing AM251 cells to chemovar fractions extracted using a non-polar solvent, thereby isolating a broader spectrum of constituents. By employing LC/GCMS in conjunction with Nuclear Magnetic Resonance (NMR), we have identified and quantified nine* compounds present in the non-polar CSCE that exhibit significant efficacy (0.1 μM) in inducing cytotoxicity* in GBM tumor cells. Conversely, the polar fraction in our experiment did not demonstrate efficacy against UM251 cells. The quantification of individual compounds within a cannabis extraction that selectively induces cell death in brain tumors holds promise for guiding future research and facilitating the development of a standardized CSCE for GBM therapy.
文摘Surfactant is widely used in the industry,and its determination is important in both performance and quality control consideration.A liquid chromatography coupling mass spectrometry(LC-MS)method was established for analyzing surfactants in lubricant.Three surfactants,including polyoxyethylene(9)nonyl phenyl ether,polyoxyethylene(10)decanamine ether,and polyoxyethylene(5)oleylamine ether were identified.
基金This work was financially supported by the National Natural Science Foundation of China (Grant No. 51178438) and the National Basic Research Program of China (No. 2008CB418201).
文摘Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments, and fish muscles were developed. In water samples, drugs were extracted with solid-phase extraction (SPE) by passing 1000 mL of water through hydrophilic lipophilic balanced (HLB) SPE cartridges. Sediment samples were solvent-extracted, followed by tandem SPE (strong anion exchange (SAX) + HLB) clean-ups. Fish muscles were extracted by a mixture of acetonitrile and citric buffer (80:20, v/v) solution, and cleaned by SPE. Liquid chromatography-tandem mass spectrometry (LC-MS/ MS) with multiple reaction monitoring (MRM) detection was employed to quantify all compounds. The recoveries for the antibiotics in the spiked water, sediment, and fish samples were 60.2%-95.8%, 48.1%-105.3%, and 59.8%- 103.4%, respectively. The methods were applied to samples taken from Dianchi Lake, China. It showed that concentrations of the detected antibiotics ranged from limits of quantification (LOQ) to 713.6 ng- L1 (ofloxacin) in surface water and from less than LOQ to 344.8 μg·kg-1 (sulphamethoxazole) in sediments. The number of detected antibiotics and the overall antibiotic concentrations were higher in the urban area than the rural area, indicating the probable role of livestock and human activities as important sources of antibiotic contamination. In fish muscles, the concentration of norfioxacin was the highest (up to 38.5 μg·kg-1), but tetracyclines and macrolides were relatively low. Results showed that the methods were rapid and sensitive, and capable of determining several classes of antibiotics from each of the water, sediment, and fish matrices in a single run.
文摘To establish HPLC electrospray ionization mass spectrometry (HPLC-ESI MS) method for determination of osthole in food additive.The samples were dipped in methanol overnight and extracted with it by ultrasonic instrument,then the supernatant was send to sampler for detection.Sample was chromatographed using 0.4%HAc solution-MeOH (35:65,by volume) mobile phase on an Xterra MS C18 column.Analyte determination was performed by ESI MS/MS in the multiple reaction monitoring(MRM)mode.The established method of LC-MS/MS determining the concentration of osthole in food additive has the characteristic of strong specificity,high sensitivity and good reproducibility.The linear range of papaverine was 0.001-10 μg/mL,method recovery was 97.42%,RSD was 8.37%,the limit of detection was 1 ng/mL and the limit of quantitation was 0.001 μg/mL.
基金Supported by the Science&Technology Basic Resources Investigation Program of China(No.2018FY100200)the National Natural Science Foundation of China(Nos.32072329,41976110)+1 种基金the Central PublicInterest Scientifi c Institution Basal Research Fund,CAFS(No.2020TD71)the Earmarked Fund for CARS(CARS-49)。
文摘A total of 133 shellfish samples were collected in seven cities of Shandong Province,China,from May to October,2019.The domoic acid(DA)concentrations were determined by liquid chromatographytandem mass spectrometry(LC-MS/MS),and their distribution characteristics were investigated.DA concentration was detected high in over 1/3(36.1%)of the samples of four kinds of shellfish in all three seasons in range from 0 to 102μg/kg.The highest DA concentrations were 102,101,36.7,and 10.2μg/kg in Crassostrea gigas,Chlamys farreri,Mactra veneriformis,and Mytilus edulis,respectively.Geographically,Yantai(22.0μg/kg)and Weihai(16.9μg/kg)showed relatively high concentrations of DA,whereas Rizhao and Dongying presented only 0.85-and 1.76-μg/kg DA,respectively.DA concentrations in the shellfish samples were strongly related to seasonal changes,being significantly higher in autumn and summer than that in spring.The DA risk exposure assessments indicate that dietary seafood consumption did not pose a health threat to general human population.In addition,three isomers(isoA,isoD,isoE)and 5′-epimer DA were detected in 3.00%-15.80%of the shellfish samples.This study is the first to observe DA and its isomers in shellfish samples of Shandong Province.The results demonstrate that DA contamination is very common and should be continuously monitored.
基金Supported by the National Natural Science Foundation of China(Nos.81603182, 81430087, 81673396).
文摘A reliable liquid chromatography-tandem mass spectrometric(LC-MS/MS) method was developed and va- lidated for the simultaneous determination of vancomycin and voriconazole in human plasma. The analytes and internal standard 10-hydroxycarbazepine were separated at a flow rate of 0.9 mL/min using a Zorbax SB-C18 column (50 min×4.6 mm, 2.7 μm). Positive ion electrospray ionization was used to detect vancomycin, voriconazole and intrenal standard(IS) 10-hydroxycarbazepine followed by multiple reaction monitoring(MRM) of the transition at m/z 725.5→144.2, 350.3→281.0 and 253.1→208.0, respectively. The total run time for both vancomycin and voriconazole samples was 5 min; 0.30μg/mL was the lower limit of quantification. The precision of intraday and interday was no more than 12.4%. The method was successfully and resoundingly applied in therapeutic drug monitoring of 156 patients treated with vancomycin and voriconazole.
文摘Hemipteran insects are the most devastating pest for different crops of high economic value. Colocasia esculenta tuber agglutinin (CEA), a mannose binding monocot lectin from araceae family was previously reported by the present group to be effective against some members of this class of pests. In the present study, efficacy of this potent lectin has been extended to cotton aphid (Aphis gossypii) which is becoming a highly damaging pest of cotton in recent days. Because, like other aphids, A. gossypii not only extracts the phloem fluid but also transmit disease causing viruses and add to the high degree of yield loss. Efficacy of the lectin on cotton aphid as well as other hemipteran insects prompted us further to clone the protein coding gene. Very little sequence information of this gene was available in the database. Hence, attempt had been made to study the protein through liquid chromatography-tandem mass spectrometry (LC-MS/MS) to have the detailed peptide information. On the basis of the peptide homology information obtained from LC-MS/MS the complete coding sequence of CEA was determined. The coding sequence corresponding to CEA was cloned further using primers designed on the basis of above information and genome walk technology for its potential utilisation in insect management programme.
基金the National Natural Science Foundation of China,the Science and Technology Major Specialized Projects for "Significant New Drugs Creation" of the 12th Five-year Plan of China,the National Key Technology R&D Program of the Ministry of Science and Technology,China
文摘Astilbin is a potential immunosuppressive agent with minor cytotoxicity. Its oral bioavailability is supposed to be rather low and therefore a sensitive analytical method is required for its pharmacokinetic study after oral administration. A simple, sensitive and rapid liquid chromatography-tandem mass spectrometry(LC-MS/MS) method was developed and validated for the determination of astilbin in rat plasma. Plasma samples were subjected to liquid-liquid extraction with ethyl acetate and separated by reversed phase high performance liquid chromatography(HPLC) with methanol-0.01%(volume fraction) formic acid(50:50, volume ratio) as mobile phase. Quantitive determination was achieved on negative LC-MS/MS by a multiple reaction moitoring method with transitions m/z 449.1→150.9(quantifier) and m/z 449.1→284.9(qualifier) for astilbin and m/z 128.9→42.0 for internal standard(IS). A lower limit of quantification(LLOQ) of ng/mL was achieved within a short cycle time of 3.4 min. The method was successfully applied to a pharmacokinetic study involving oral and intravenous administrations of 6 mg/kg astilbin to six rats.
基金Supported by the National Natural Science Foundation of China(Nos.81430087, 81473142, 81102383) and the Prej ect of China Equipment and Education Resources System(CERS)(No.CERS-1-70).
文摘A rapid and sensitive liquid chromatography-tandem mass spectrometry(LC-MS/MS) method for the de- termination of cefotetan in human plasma was developed and validated. After the protein precipitation of sample with acetonitrile, the analyte and internal standard(IS), tramadol, were separated on a Zorbax XDB C8 column using ace- tonitrile/1%(volume fraction) formic acid(volume ratio 35:65, pH=2.5) as mobile phase at a flow rate of 1.0 mL/min with a 1 : 1 split. The detection was performed by electrospray ionization with positive ion mode, followed by multiple reaction monitoring of the transitions for cefotetan at m/z 576.3→460.2(quantifier) and m/z 576.3→432.2(qualifier) and for IS at m/z 264.1→58.1. Cefotetan and IS were eluted at 1.86 and 1.87 rain, respectively. The assay was linear over the concentration range of 0.1-100 gg/mL for 20 μL of human plasma only with intra- and inter-day preci- sions(expressed as the relative standard deviation) of less than 6.62% and accuracies(as relative error) of +1.31%. The method was applied to the pharmacokinetic study of a l-h intravenous infusion of 1.0 g of cefotetan disodium for human volunteers(n=6).
基金This work was supported by the Beijing Natural Science Foundation Essential Research Project,China(No.Z170002)the National Natural Science Foundation of China(Nos.22125401,22074003,82071226 and 81901145).
文摘Migraine is an episodic neurological disorder and the second most disabling disease with unclear pathogenesis.Since dietary adjustment and probiotics supplement can improve the symptoms of migraine,the intestinal flora metabolites of bile acids(BAs)attract attentions in this work.21 BAs,including cholic acid(CA),chenodeoxycholic acid(CDCA),deoxycholic acid(DCA),lithocholic acid(LCA),ursodeoxycholic acid(UDCA),hyocholic acid(HCA),hyodeoxycholic acid(HDCA)and their glycine-and taurine-conjugated species,were compared in serum of migraine patients and healthy controls using liquid chromatography-tandem mass spectrometry(LC-MS/MS),which is the first study about the correlation between BAs and migraine.Two secondary BAs,DCA and LCA as well as their glycine-and taurine-conjugated forms,were demonstrated with significant difference between male patients and male controls,while no obvious difference was found in the two female groups.The result indicated that the variation of BAs might be gender-related when referred to migraine,which would emphasize the importance of gender-stratified analysis for the disease with varying morbidity in male and female.Five differential metabolites may serve as potential serum biomarkers for the male migraine patients,providing a new sight for the understanding and biomarker exploring of the migraine in male.