[Objectives]To extract and purify perfluoroalkyl and polyfluoroalkyl substances(PFAS)from aquatic products and determine the optimal pretreatment conditions.[Methods]The QuEChERS method was employed for the extraction...[Objectives]To extract and purify perfluoroalkyl and polyfluoroalkyl substances(PFAS)from aquatic products and determine the optimal pretreatment conditions.[Methods]The QuEChERS method was employed for the extraction and purification of PFAS in aquatic products.The detection of PFAS was carried out using liquid chromatography-tandem mass spectrometry(LC-MS/MS)in ESI negative ion mode with multiple reaction monitoring(MRM),and quantification was performed using the external standard method.By optimizing instrument parameters such as ion source temperature,spray voltage,and collision energy,high selectivity and sensitivity of the detection were ensured.[Results]The established calibration curves for 28 PFAS compounds compounds,covering a range of 0.02 to 20 ng/mL,demonstrated excellent linearity.Spike recovery tests yielded limits of detection(LOD)between 0.02 and 0.5μg/kg for the 28 PFAS compounds compounds,with recovery rates ranging from 72.2%to 113.0%.[Conclusions]The method established in this study demonstrates excellent linearity,and is accurate,reliable,efficient,simple,and rapid.It possesses considerable practical applicability and can be used for the quality and risk assessment of 28 PFAS compounds compounds in aquatic products,indicating high practical utility.展开更多
[Objectives]This study was conducted to establish a detection method for the simultaneous determination of 18 perfluorinated compounds(PFCs)in milk tea by ultra-high performance liquid chromatography-tandem mass spect...[Objectives]This study was conducted to establish a detection method for the simultaneous determination of 18 perfluorinated compounds(PFCs)in milk tea by ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS).[Methods]The samples were first subjected to precipitation of proteins by potassium ferrocyanide solution and zinc acetate solution,and then extracted by acetonitrile and detected by LC-MS/MS.Next,sodium chloride was added,and after vortex centrifugation,the acetonitrile layer was dried by blowing with nitrogen.Subsequently,1 ml of methanol was added to prepare a test solution.An ACQUITY UPLC BEH C18(2.6 m,2.1 mm×100 mm)chromatographic column was used for liquid phase separation,and gradient elution was performed using 10 mmol ammonium acetate solution-acetonitrile as the mobile phase.The MS detection adopted the MRM mode for acquisition,positive and negative ion mode switching for simultaneous determination,and external standard method for quantification.[Results]In the linear ranges of the target substances,the correlation coefficients R^(2)were all greater than 0.99.The detection limits of the method was in the range of 0.001-0.05μg/kg,and the quantitation limits were in the range of 0.03-0.20 ng/L.The recovery values ranged from 72.8%to 110.5%.[Conclusions]This method has high sensitivity and good accuracy,and thus strong practical value.展开更多
Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more ...Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines （TCs）, sulfanilamides （SAs）, and quinolones （QLs）. The method consists of solid-phase extraction （SPE） and liquid chromatography-tandem mass spectrometry （LC-MS/MS） analysis, using electrospray ionization （ESI） in positive mode. The SPE was performed with Oasis HLB and Oasis MCX cartridges. Chromatographic separation on a Cr8 column was achieved using a binary eluent containing methanol and water with 0.1% formic acid. Typical recoveries of the analytes ranged from 67.4% to 109.3% at a fortification level of 100 ng/L. The precision of the method, calculated as relative standard deviation （RSD）, was below 14.6% for all the compounds. The limits of detection （LODs） varied from 0.45 pg to 7.97 pg. The method was applied to detemaine the target analytes in coastal waters of the Yellow Sea in Liaoning, China. Among the tested antibiotics, 31 were found in coastal ＇waters, with their concentrations between the LOD and 212.5 ng/L. These data indicate that this method is valid for analysis of antibiotics in coastal waters. The study first reports such a large number of antibiotics along the Yellow Sea coast of Liaoning, and should facilitate future comprehensive evaluation of antibiotics in coastal ecosystems展开更多
A rapid and accurate high performance liquid chromatography tandem mass spectrometry（HPLS-MS） method was established for quantification of chlorpromazine in pork. The porcine samples were pretreated with acetonitril...A rapid and accurate high performance liquid chromatography tandem mass spectrometry（HPLS-MS） method was established for quantification of chlorpromazine in pork. The porcine samples were pretreated with acetonitrile to precipitate proteins and followed by extraction with tert--butyl methyl ether（TBME）. The separation was performed on a 5 μm Agilent XDB--C18 column with gradient elution. The mobile phase A was 0.01 mol/L ammonium formate in water and mobile phase B was acetonitrile. The flow rate was at 0.8 mL/min. Quantification was performed on a triple-quadrupole tandem mass spectrometer using the multiple selected reaction monitoring（MRM） mode. Transition of m/z ＋319.1 to 58.1 was used for the quantification of chlorpromazine. The method was validated at the concentration range of 0.4040 μg/kg to 8.080 μg/kg for chlorpromazine with correlation coefficient of 0.9999. The spiked recoveries were more than 80.0% and the limit of detection（LOD） was 0.052 μg/kg. The developed method, which offers advantages of convenience, rapid, specificity and higher sensitivity, can be used for determination of chlorpromazine hydrochloride in porcine muscles.展开更多
A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 s...A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues.展开更多
To establish an analytical method for determination of four bisphenols （BPA, BPB, BPF, and BPS） and two alkylphenols （4-n-OP, 4-n-NP） in water by ultra performance liquid chromatography- tandem mass spectrometry ...To establish an analytical method for determination of four bisphenols （BPA, BPB, BPF, and BPS） and two alkylphenols （4-n-OP, 4-n-NP） in water by ultra performance liquid chromatography- tandem mass spectrometry （UPLC/MS/MS）. The water samples were extracted and condensed with solid-phase extraction （SPE） using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%.展开更多
[Objective] This study aimed to develop a method of C_18-functionalized magnetic silica nanoparticles solid phase extraction-high performance liquid chro- matography-tandem mass spectrometry for the determination of s...[Objective] This study aimed to develop a method of C_18-functionalized magnetic silica nanoparticles solid phase extraction-high performance liquid chro- matography-tandem mass spectrometry for the determination of sulfadimidine in royal jelly. [Method] The royal jelly samples were pretreated by MCX SPE column and C_18-functionalized magnetic silica nanoparticles, and the purified samples were de- tected by HPLC-MS/MS. [Result] The detection method showed a good linear rela- tionship in the range of 5-80 ugkg （r=0.993 1）. The recovery ranges were between 93%- 104% with the relative standard deviations （RSD） below 11.3%. [Conclusion] Combined with automation equipment, the method is simple, fast, time-saving, and easy to real- ize the automation of sulfadimidine in the royal jelly samples before determination.展开更多
Summary： A liquid chromatography-tandem mass spectrometry （LC-MS/MS） method was developed and validated for the determination of butoconazole in human plasma. Human plasma samples of 0.2 μL were pretreated by a si...Summary： A liquid chromatography-tandem mass spectrometry （LC-MS/MS） method was developed and validated for the determination of butoconazole in human plasma. Human plasma samples of 0.2 μL were pretreated by a single step protein precipitation procedure and analyzed using a high performance liquid chromatography （HPLC） electrospray tandem mass spectrometer system. The compounds were eluted isocratically on an Inertsil ODS-SP column （100 min×2.1 mm, 3 μm）, ionized using a positive ion atmospheric pressure electrospray ionization source and analyzed using multiple reaction monitoring （MRM） mode. The ion transitions monitored were m/z 412.8→q65.1 for butoconazole and m/z 453.4→230.3 for the internal standard. The chromatographic run time was 3.5 min per injection, with retention time of 2.47 rain and 2.15 min for butoconazole and repaglinide, respectively. The method was validated to be linear over the range of 20 to 8000 pg/mL （r〉0.999） by using a weighted （1/x2） quadratic regression. The mean recovery rate was more than 86.7%, and the intra- and inter-day precision of the quality control samples （QCs） was less than 8.3% and the accuracy ranged from 96.0% to 110.2%, which indicated that the quantitative method was reliable and accurate. The method is simple, rapid, and has been applied successfully to a pharmacokinetics study of butoconazole nitrate suppositories in healthy Chinese females.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
With the long -term and irrational use of veterinary drugs and drug additives in the process of animal feeding, the veterinary drug resi- dues in animals and their additives can be ingested into the human body and pos...With the long -term and irrational use of veterinary drugs and drug additives in the process of animal feeding, the veterinary drug resi- dues in animals and their additives can be ingested into the human body and pose potential threat to human health. Detection of veterinary drug resi- dues are extremely important practical significance to protect the ecological environment and human health. In recent years, liquid chromatography -tandem mass spectrometry has been widely used in vetednary drug residue detection because of its applicability, qualitative and quantitative fea- tures as well as high sensitivity. This article summarized the application of liquid chromatography -tandem mass spectrometry in detection veterinary drug residues from feed, animal products, arid udne as well as illicit drugs and harmful additives.展开更多
Objective To establish a rapid,sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of acyclovir (the metabolite of valacyclovir hydrochloride) in human plasma...Objective To establish a rapid,sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of acyclovir (the metabolite of valacyclovir hydrochloride) in human plasma. Methods After addition of ganciclovir as internal standard (IS),plasma samples were prepared by one-step protein precipitation using acetonitrile as precipitant,followed by an isocratic elution with 0.1% formic acid solution-methanol (95∶5,v/v) on an Agilent ZORBAX SB-C18 (150mm×2.1mm i.d.,3.5μm) column. Detection was performed on a triple-quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operating in positive ion and selected reaction monitoring (SRM) mode with the precursor to product ion transitions m/z 226.2→152.1 for acyclovir and m/z 256.2→152.1 for the IS. Results The analytical results demonstrated a good linearity over the ranges from 0.005 to 4μg/mL (r=0.9999) for valacyclovir hydrochloride. The relative standard deviations (RSD) of intra-batch and inter-batch were less than 4.06% and 9.23%,respectively. The limit of detection and lower limit of quantification in human plasma were 2ng/mL and 5ng/mL,respectively. Conclusion The method was simple,sensitive,accurate and reproducible and has been successfully applied to a bioequivalence study of valacyclovir hydrochloride capsules in Chinese healthy male volunteers.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 aim of this work was to develop a liquid chromatography-tandem mass spectrometry method for the determination of milk allergen and egg allergen in food products.Signature peptides GGLEPINFQTAADQAR,VGINYWLAHK,VLVLD...The aim of this work was to develop a liquid chromatography-tandem mass spectrometry method for the determination of milk allergen and egg allergen in food products.Signature peptides GGLEPINFQTAADQAR,VGINYWLAHK,VLVLDTDYK,FFVAPFPEVFGK,and NAVPITPTLNR were confirmed and synthesized as the quantitative peptide of ovalbumin,α-lactalbumin,β-lactoglobulin,α_(S1)-casein andα_(S2)-casein,the relative isotope-labeled internal standards were used in the quantitative analysis.Linear range was in the range of0.5-5000.0 nmol/L for egg and milk allergen in bread,cake,cookie,rice crust and wheat flour samples with free from egg and milk,the limits of detection of milk allergens and egg allergen were in the range between0.94 mg/100 g and 56.71 mg/100 g,limits of quantification of milk allergens and egg allergen were in the range between 2.36 mg/100 g and 141.78 mg/100 g.The recoveries ranged from 76.7%to 122.8%,the relative standard deviations were in the range of 1.60%-15.60%.The developed method has been successfully used for the detection of egg and milk allergen in various food samples.展开更多
[Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-g...[Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-glucuronidase and extracted with 5%acetic acid-acetonitrile(1:99,V/V)solution.An Eclipse plus C 18 column was used for separation,and the MRM mode was used for qualitative analysis,and the external standard method was used for quantitative analysis of matrix standard solutions.[Results]Under the optimal conditions,the retention time of the 14 kinds ofβ-receptor agonists ranged from 1.0 to 9.5 min.When the mass concentration was in the range of 0.05-0.50μg/ml,the linear relationship ofβ-receptor agonists was good,with correlation coefficients(r)≥0.9992.The detection limits of the method were in the range of 0.04-0.87μg/kg,and the quantitative limits were in the range of 0.35-1.86μg/kg.The average recovery values were in the range of 82.8%-108.9%,with RSDs(n=6)in the range of 1.9%-6.7%.[Conclusions]The method is simple,sensitive,reproducible,accurate,and can be used for simultaneous determination of the 14 kinds ofβ-receptor agonist residues in mutton.展开更多
[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The ...[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The samples were extracted with an acetonitrile water solution(8∶2),0.1 mol/L hydrochloric acid and a purification extraction bag with shaking.Centrifugation was performed to obtain supernatants,which were added to purification tubes containing PSA and C_(18) for purification,and then filtered with membranes for determination.Each test solution was separated by a ZORBAX Eclipse plus C_(18) column with acetonitrile and 5 mmol/L ammonium acetate as mobile phases,and determined with electrospray ionization and multiple reaction monitoring.[Results]The method had good linearity in the concentration range of 1.0-50 ng/ml,and the correlation coefficient was 0.9997.The limit of detection was 0.25μg/kg and the limit of quantification was 0.75μg/kg.The recovery was between 87.4%and 112.5%,and the RSD%was between 0.5%and 10.0%.[Conclusions]The method has simple operation and high sensitivity,and is suitable for trace detection of sodium pentachlorophenoxide in large quantities of animal-derived food.展开更多
A highly sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the quantification of vancomycin (VAN) in low volumes of rabbit serum. For each analysis,...A highly sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the quantification of vancomycin (VAN) in low volumes of rabbit serum. For each analysis, 2 μL rabbit serum was precipitated with methanol that contained the internal standard teicoplanin (TEI). The supernatant was transferred into a 384 well-plate, diluted with water, covered with a pierceable silicone mat and 5 μL was analyzed in positive ionization mode. The UHPLC-MS/MS consisted of an Agilent 1290 Infinity UHPLC system connected to an AB Sciex QTrap®5500 hybrid linear ion-trap triple quadrupole mass spectrometer equipped with a Turbo Spray source. Chromatographic separation was achieved using a Waters Acquity UPLC BEH C18 (1.7 μm, 2.1 mm × 100 mm) column, a VanGuard (1.7 μm, 2.1 × 5 mm) guard column and a mobile phase of water and methanol both containing 5 mM ammonium acetate with 0.1% formic acid. VAN was quantified with multiple reaction monitoring using the transitions of m/z 725.5/144.2, and TEI was monitored at m/z 940.6/316.4. The accuracy, precision, linearity, range and lower limit of quantification (LLOQ) were determined. The accuracy was ≤9.93% and the precision was ≤10.6%. The range was established as 0.1 to 40 μg·mL-1. The LLOQ was 0.1 μg·mL-1 VAN requiring 2 μL of sample with an accuracy of -20.2% and precision of 8.39%. The method was applied successfully to determine the VAN concentrations in rabbit serum after the i.v. administration of VAN via implanted ear catheters.展开更多
The residual clothianidin in rice was determined by Agilent ultra-performance liquid chromatography-tandem mass spectrometry, quantified by external standard method, adjusted the elution gradient of mobile phase and t...The residual clothianidin in rice was determined by Agilent ultra-performance liquid chromatography-tandem mass spectrometry, quantified by external standard method, adjusted the elution gradient of mobile phase and the parameters of ion monitoring and analysis, and compared the precision of recovery and repeatability of parallel standard addition. The experimental results showed that the clothianidin residue in rice was ultrasonically extracted by 0.1% acetic acid-acetonitrile and purified by matrix dispersed solid-phase extractant, and the linearity of the test was good. The correlation coefficient R was greater than or equal to 0.999, and the quantitative limit was 0.010mg/kg. The recoveries of clothianidin residue were 96.9% and 95.0% respectively, and the repeatability precision RSD was 1.48%. In this paper, the recovery and precision of parallel standard addition for determination of clothianidin residues in rice by Agilent ultra-performance liquid chromatography-tandem mass spectrometry were studied. Good results were obtained, which could provide reference for the detection of pesticide residues in other cereals.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
In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purificatio...In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.展开更多
In this paper,we developed and validated a simple,sensitive,and selective high-performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS） method to identify and measure the following prohibited substance...In this paper,we developed and validated a simple,sensitive,and selective high-performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS） method to identify and measure the following prohibited substances that may be found in cosmetic products：minoxidil,hydrocortisone, spironolactone,estrone,canrenone,triamcinolone acetonide and progesterone.Chromatographic separation was performed on a Waters Symmetry C18（100 mm×2.1 mm,3.5μm particle size） with a gradient elution system composed of 0.2%（v/v） formic acid aqueous solution and methanol containing 0.2%（v/v） formic acid at a flow rate of 0.3 mL/min.The substances were detected using a triple quadrupole mass spectrometer in the multiple reaction monitoring mode with an electrospray ionization source.All of the calibration curves showed good linearity（r 〉 0.999） within the tested concentration ranges.The limit of detection was 〈25 pg.The relative standard deviations for intraday precision for each of the prohibited substances were 〈3.5%at two concentration levels（2μg/g,10μg/g）. The relative recovery rate for each of the prohibited substances ranged from 91.8%to 111%at three concentration levels（0.1μg/g,2μg/g,10μg/g）,including the limit of quantification.In conclusion,we have developed and validated a method that can identify seven prohibited substances in cosmetic products.展开更多
文摘[Objectives]To extract and purify perfluoroalkyl and polyfluoroalkyl substances(PFAS)from aquatic products and determine the optimal pretreatment conditions.[Methods]The QuEChERS method was employed for the extraction and purification of PFAS in aquatic products.The detection of PFAS was carried out using liquid chromatography-tandem mass spectrometry(LC-MS/MS)in ESI negative ion mode with multiple reaction monitoring(MRM),and quantification was performed using the external standard method.By optimizing instrument parameters such as ion source temperature,spray voltage,and collision energy,high selectivity and sensitivity of the detection were ensured.[Results]The established calibration curves for 28 PFAS compounds compounds,covering a range of 0.02 to 20 ng/mL,demonstrated excellent linearity.Spike recovery tests yielded limits of detection(LOD)between 0.02 and 0.5μg/kg for the 28 PFAS compounds compounds,with recovery rates ranging from 72.2%to 113.0%.[Conclusions]The method established in this study demonstrates excellent linearity,and is accurate,reliable,efficient,simple,and rapid.It possesses considerable practical applicability and can be used for the quality and risk assessment of 28 PFAS compounds compounds in aquatic products,indicating high practical utility.
基金Supported by Natural Science Foundation of Hunan Province(2024JJ8266).
文摘[Objectives]This study was conducted to establish a detection method for the simultaneous determination of 18 perfluorinated compounds(PFCs)in milk tea by ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS).[Methods]The samples were first subjected to precipitation of proteins by potassium ferrocyanide solution and zinc acetate solution,and then extracted by acetonitrile and detected by LC-MS/MS.Next,sodium chloride was added,and after vortex centrifugation,the acetonitrile layer was dried by blowing with nitrogen.Subsequently,1 ml of methanol was added to prepare a test solution.An ACQUITY UPLC BEH C18(2.6 m,2.1 mm×100 mm)chromatographic column was used for liquid phase separation,and gradient elution was performed using 10 mmol ammonium acetate solution-acetonitrile as the mobile phase.The MS detection adopted the MRM mode for acquisition,positive and negative ion mode switching for simultaneous determination,and external standard method for quantification.[Results]In the linear ranges of the target substances,the correlation coefficients R^(2)were all greater than 0.99.The detection limits of the method was in the range of 0.001-0.05μg/kg,and the quantitation limits were in the range of 0.03-0.20 ng/L.The recovery values ranged from 72.8%to 110.5%.[Conclusions]This method has high sensitivity and good accuracy,and thus strong practical value.
基金Supported by Young Scientists Research Program (No. 2009507)the Key Laboratory of Marine Bioactive Substances and Modern Analytical Techniques (No. MBSMAT-2010-04),SOA of China
文摘Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines （TCs）, sulfanilamides （SAs）, and quinolones （QLs）. The method consists of solid-phase extraction （SPE） and liquid chromatography-tandem mass spectrometry （LC-MS/MS） analysis, using electrospray ionization （ESI） in positive mode. The SPE was performed with Oasis HLB and Oasis MCX cartridges. Chromatographic separation on a Cr8 column was achieved using a binary eluent containing methanol and water with 0.1% formic acid. Typical recoveries of the analytes ranged from 67.4% to 109.3% at a fortification level of 100 ng/L. The precision of the method, calculated as relative standard deviation （RSD）, was below 14.6% for all the compounds. The limits of detection （LODs） varied from 0.45 pg to 7.97 pg. The method was applied to detemaine the target analytes in coastal waters of the Yellow Sea in Liaoning, China. Among the tested antibiotics, 31 were found in coastal ＇waters, with their concentrations between the LOD and 212.5 ng/L. These data indicate that this method is valid for analysis of antibiotics in coastal waters. The study first reports such a large number of antibiotics along the Yellow Sea coast of Liaoning, and should facilitate future comprehensive evaluation of antibiotics in coastal ecosystems
文摘A rapid and accurate high performance liquid chromatography tandem mass spectrometry（HPLS-MS） method was established for quantification of chlorpromazine in pork. The porcine samples were pretreated with acetonitrile to precipitate proteins and followed by extraction with tert--butyl methyl ether（TBME）. The separation was performed on a 5 μm Agilent XDB--C18 column with gradient elution. The mobile phase A was 0.01 mol/L ammonium formate in water and mobile phase B was acetonitrile. The flow rate was at 0.8 mL/min. Quantification was performed on a triple-quadrupole tandem mass spectrometer using the multiple selected reaction monitoring（MRM） mode. Transition of m/z ＋319.1 to 58.1 was used for the quantification of chlorpromazine. The method was validated at the concentration range of 0.4040 μg/kg to 8.080 μg/kg for chlorpromazine with correlation coefficient of 0.9999. The spiked recoveries were more than 80.0% and the limit of detection（LOD） was 0.052 μg/kg. The developed method, which offers advantages of convenience, rapid, specificity and higher sensitivity, can be used for determination of chlorpromazine hydrochloride in porcine muscles.
基金supported by the Natural Science Foundation of Zhejiang Province,China(No.LY17C200009)the Foundation of Zhejiang Educational Committee(No.Y201328477)
文摘A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues.
基金supported by the Preventive medicine and public health research project of Anhui,China(No.2011Y0103)the Natural Science Foundation of Anhui,China(No.11040606M216)
文摘To establish an analytical method for determination of four bisphenols （BPA, BPB, BPF, and BPS） and two alkylphenols （4-n-OP, 4-n-NP） in water by ultra performance liquid chromatography- tandem mass spectrometry （UPLC/MS/MS）. The water samples were extracted and condensed with solid-phase extraction （SPE） using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%.
基金Supported by the Innovation Fund for Technology Based Firms of Ministry of Science and Technology(09C26214425280)the National Key Technology R&D Program during the 12th Five-Year Plan Period(2012BAK17B10)the International S&T Cooperation and Communication Program of China(2011DFA32930)~~
文摘[Objective] This study aimed to develop a method of C_18-functionalized magnetic silica nanoparticles solid phase extraction-high performance liquid chro- matography-tandem mass spectrometry for the determination of sulfadimidine in royal jelly. [Method] The royal jelly samples were pretreated by MCX SPE column and C_18-functionalized magnetic silica nanoparticles, and the purified samples were de- tected by HPLC-MS/MS. [Result] The detection method showed a good linear rela- tionship in the range of 5-80 ugkg （r=0.993 1）. The recovery ranges were between 93%- 104% with the relative standard deviations （RSD） below 11.3%. [Conclusion] Combined with automation equipment, the method is simple, fast, time-saving, and easy to real- ize the automation of sulfadimidine in the royal jelly samples before determination.
基金supported by National Science&Technology Specific Projects in the 12th Five-Year Plan of China(No.2011ZX09302-002-01)
文摘Summary： A liquid chromatography-tandem mass spectrometry （LC-MS/MS） method was developed and validated for the determination of butoconazole in human plasma. Human plasma samples of 0.2 μL were pretreated by a single step protein precipitation procedure and analyzed using a high performance liquid chromatography （HPLC） electrospray tandem mass spectrometer system. The compounds were eluted isocratically on an Inertsil ODS-SP column （100 min×2.1 mm, 3 μm）, ionized using a positive ion atmospheric pressure electrospray ionization source and analyzed using multiple reaction monitoring （MRM） mode. The ion transitions monitored were m/z 412.8→q65.1 for butoconazole and m/z 453.4→230.3 for the internal standard. The chromatographic run time was 3.5 min per injection, with retention time of 2.47 rain and 2.15 min for butoconazole and repaglinide, respectively. The method was validated to be linear over the range of 20 to 8000 pg/mL （r〉0.999） by using a weighted （1/x2） quadratic regression. The mean recovery rate was more than 86.7%, and the intra- and inter-day precision of the quality control samples （QCs） was less than 8.3% and the accuracy ranged from 96.0% to 110.2%, which indicated that the quantitative method was reliable and accurate. The method is simple, rapid, and has been applied successfully to a pharmacokinetics study of butoconazole nitrate suppositories in healthy Chinese females.
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With the long -term and irrational use of veterinary drugs and drug additives in the process of animal feeding, the veterinary drug resi- dues in animals and their additives can be ingested into the human body and pose potential threat to human health. Detection of veterinary drug resi- dues are extremely important practical significance to protect the ecological environment and human health. In recent years, liquid chromatography -tandem mass spectrometry has been widely used in vetednary drug residue detection because of its applicability, qualitative and quantitative fea- tures as well as high sensitivity. This article summarized the application of liquid chromatography -tandem mass spectrometry in detection veterinary drug residues from feed, animal products, arid udne as well as illicit drugs and harmful additives.
文摘Objective To establish a rapid,sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of acyclovir (the metabolite of valacyclovir hydrochloride) in human plasma. Methods After addition of ganciclovir as internal standard (IS),plasma samples were prepared by one-step protein precipitation using acetonitrile as precipitant,followed by an isocratic elution with 0.1% formic acid solution-methanol (95∶5,v/v) on an Agilent ZORBAX SB-C18 (150mm×2.1mm i.d.,3.5μm) column. Detection was performed on a triple-quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operating in positive ion and selected reaction monitoring (SRM) mode with the precursor to product ion transitions m/z 226.2→152.1 for acyclovir and m/z 256.2→152.1 for the IS. Results The analytical results demonstrated a good linearity over the ranges from 0.005 to 4μg/mL (r=0.9999) for valacyclovir hydrochloride. The relative standard deviations (RSD) of intra-batch and inter-batch were less than 4.06% and 9.23%,respectively. The limit of detection and lower limit of quantification in human plasma were 2ng/mL and 5ng/mL,respectively. Conclusion The method was simple,sensitive,accurate and reproducible and has been successfully applied to a bioequivalence study of valacyclovir hydrochloride capsules in Chinese healthy male volunteers.
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 National Key Research and Development Program of China(2019YFC1606400)Science and Technology Project of State Administration for Market Regulation(2021MK023)+1 种基金Hebei Province High-level Talent Funding Program(A201901008)Research Project of Hebei Administration for Market Regulation(2020ZD12)。
文摘The aim of this work was to develop a liquid chromatography-tandem mass spectrometry method for the determination of milk allergen and egg allergen in food products.Signature peptides GGLEPINFQTAADQAR,VGINYWLAHK,VLVLDTDYK,FFVAPFPEVFGK,and NAVPITPTLNR were confirmed and synthesized as the quantitative peptide of ovalbumin,α-lactalbumin,β-lactoglobulin,α_(S1)-casein andα_(S2)-casein,the relative isotope-labeled internal standards were used in the quantitative analysis.Linear range was in the range of0.5-5000.0 nmol/L for egg and milk allergen in bread,cake,cookie,rice crust and wheat flour samples with free from egg and milk,the limits of detection of milk allergens and egg allergen were in the range between0.94 mg/100 g and 56.71 mg/100 g,limits of quantification of milk allergens and egg allergen were in the range between 2.36 mg/100 g and 141.78 mg/100 g.The recoveries ranged from 76.7%to 122.8%,the relative standard deviations were in the range of 1.60%-15.60%.The developed method has been successfully used for the detection of egg and milk allergen in various food samples.
基金Supported by The Fourth Batch of High-end Talent Project in Hebei ProvinceTangshan Science and Technology Entrepreneurship and Innovation Leading Talent Project(21130243A).
文摘[Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-glucuronidase and extracted with 5%acetic acid-acetonitrile(1:99,V/V)solution.An Eclipse plus C 18 column was used for separation,and the MRM mode was used for qualitative analysis,and the external standard method was used for quantitative analysis of matrix standard solutions.[Results]Under the optimal conditions,the retention time of the 14 kinds ofβ-receptor agonists ranged from 1.0 to 9.5 min.When the mass concentration was in the range of 0.05-0.50μg/ml,the linear relationship ofβ-receptor agonists was good,with correlation coefficients(r)≥0.9992.The detection limits of the method were in the range of 0.04-0.87μg/kg,and the quantitative limits were in the range of 0.35-1.86μg/kg.The average recovery values were in the range of 82.8%-108.9%,with RSDs(n=6)in the range of 1.9%-6.7%.[Conclusions]The method is simple,sensitive,reproducible,accurate,and can be used for simultaneous determination of the 14 kinds ofβ-receptor agonist residues in mutton.
文摘[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The samples were extracted with an acetonitrile water solution(8∶2),0.1 mol/L hydrochloric acid and a purification extraction bag with shaking.Centrifugation was performed to obtain supernatants,which were added to purification tubes containing PSA and C_(18) for purification,and then filtered with membranes for determination.Each test solution was separated by a ZORBAX Eclipse plus C_(18) column with acetonitrile and 5 mmol/L ammonium acetate as mobile phases,and determined with electrospray ionization and multiple reaction monitoring.[Results]The method had good linearity in the concentration range of 1.0-50 ng/ml,and the correlation coefficient was 0.9997.The limit of detection was 0.25μg/kg and the limit of quantification was 0.75μg/kg.The recovery was between 87.4%and 112.5%,and the RSD%was between 0.5%and 10.0%.[Conclusions]The method has simple operation and high sensitivity,and is suitable for trace detection of sodium pentachlorophenoxide in large quantities of animal-derived food.
基金supported by the operating grant of the Collaborative Health Research Project,Natural Sciences and Engineering Research Council of Canada,and Canadian Institute of Health Research(CHRPJ 385967).
文摘A highly sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the quantification of vancomycin (VAN) in low volumes of rabbit serum. For each analysis, 2 μL rabbit serum was precipitated with methanol that contained the internal standard teicoplanin (TEI). The supernatant was transferred into a 384 well-plate, diluted with water, covered with a pierceable silicone mat and 5 μL was analyzed in positive ionization mode. The UHPLC-MS/MS consisted of an Agilent 1290 Infinity UHPLC system connected to an AB Sciex QTrap®5500 hybrid linear ion-trap triple quadrupole mass spectrometer equipped with a Turbo Spray source. Chromatographic separation was achieved using a Waters Acquity UPLC BEH C18 (1.7 μm, 2.1 mm × 100 mm) column, a VanGuard (1.7 μm, 2.1 × 5 mm) guard column and a mobile phase of water and methanol both containing 5 mM ammonium acetate with 0.1% formic acid. VAN was quantified with multiple reaction monitoring using the transitions of m/z 725.5/144.2, and TEI was monitored at m/z 940.6/316.4. The accuracy, precision, linearity, range and lower limit of quantification (LLOQ) were determined. The accuracy was ≤9.93% and the precision was ≤10.6%. The range was established as 0.1 to 40 μg·mL-1. The LLOQ was 0.1 μg·mL-1 VAN requiring 2 μL of sample with an accuracy of -20.2% and precision of 8.39%. The method was applied successfully to determine the VAN concentrations in rabbit serum after the i.v. administration of VAN via implanted ear catheters.
文摘The residual clothianidin in rice was determined by Agilent ultra-performance liquid chromatography-tandem mass spectrometry, quantified by external standard method, adjusted the elution gradient of mobile phase and the parameters of ion monitoring and analysis, and compared the precision of recovery and repeatability of parallel standard addition. The experimental results showed that the clothianidin residue in rice was ultrasonically extracted by 0.1% acetic acid-acetonitrile and purified by matrix dispersed solid-phase extractant, and the linearity of the test was good. The correlation coefficient R was greater than or equal to 0.999, and the quantitative limit was 0.010mg/kg. The recoveries of clothianidin residue were 96.9% and 95.0% respectively, and the repeatability precision RSD was 1.48%. In this paper, the recovery and precision of parallel standard addition for determination of clothianidin residues in rice by Agilent ultra-performance liquid chromatography-tandem mass spectrometry were studied. Good results were obtained, which could provide reference for the detection of pesticide residues in other cereals.
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.
基金National Key Research and Development Program of China(Project No.2018YFC1603400)Science and Technology Program of Hebei Province(Project No.19225503D)Technical Support Project of State Administration for Market Regulation(Project No.2019YJ009).
文摘In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.
基金the State Food and Drug Administration of the People's Republic of China for financially supporting this work
文摘In this paper,we developed and validated a simple,sensitive,and selective high-performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS） method to identify and measure the following prohibited substances that may be found in cosmetic products：minoxidil,hydrocortisone, spironolactone,estrone,canrenone,triamcinolone acetonide and progesterone.Chromatographic separation was performed on a Waters Symmetry C18（100 mm×2.1 mm,3.5μm particle size） with a gradient elution system composed of 0.2%（v/v） formic acid aqueous solution and methanol containing 0.2%（v/v） formic acid at a flow rate of 0.3 mL/min.The substances were detected using a triple quadrupole mass spectrometer in the multiple reaction monitoring mode with an electrospray ionization source.All of the calibration curves showed good linearity（r 〉 0.999） within the tested concentration ranges.The limit of detection was 〈25 pg.The relative standard deviations for intraday precision for each of the prohibited substances were 〈3.5%at two concentration levels（2μg/g,10μg/g）. The relative recovery rate for each of the prohibited substances ranged from 91.8%to 111%at three concentration levels（0.1μg/g,2μg/g,10μg/g）,including the limit of quantification.In conclusion,we have developed and validated a method that can identify seven prohibited substances in cosmetic products.
