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
This paper describes the quantitative determination of rare-earth elements cerium, dysprosium and non-rare-earth element copper, lead and the homogeneity examination of these four elements in yttrium oxide reference m...This paper describes the quantitative determination of rare-earth elements cerium, dysprosium and non-rare-earth element copper, lead and the homogeneity examination of these four elements in yttrium oxide reference material by isotope dilution spark source mass spectrometry (ID-SSMS). The sensitivity of the meth- od is l0^(-5)～10^(-7%). The precision is better than 6%. The accuracy is better than 5%. The interferences of the spectra and the optimum amount of the spike added to the sample are discussed. The choice of the conducting material for the sample electrodes is studied.展开更多
Background:Accurate quantification of 17-hydroxyprogesterone(17-OHP)in serum is vital for clinical and research applications.However,inter-laboratory variability in test results exists owing to the lack of a standardi...Background:Accurate quantification of 17-hydroxyprogesterone(17-OHP)in serum is vital for clinical and research applications.However,inter-laboratory variability in test results exists owing to the lack of a standardized reference measurement procedure(RMP).Therefore,in this study,we developed a highly accurate,cost-effective,and user-friendly candidate RMP(cRMP)for analyzing 17-OHP in serum.Methods:We quantified 17-OHP in serum using a one-step liquid–liquid extraction method with the addition of 17-OHP-^(13)C_(3),followed by liquid chromatography–tandem mass spectrometry.The ability of these methods to suppress interference was evaluated by chromatographic analysis.We assessed accuracy,specificity,the lower limit of quantitation,linearity,and matrix effects by following the standards specified by the Clinical and Laboratory Standards Institute.The consistency between the developed cRMP and the chemiluminescence method was evaluated through experiments with 120 clinical samples.Results:The developed cRMP required only 8 min for accurate quantification of serum 17-OHP without bias from matrix effects or interference from 19 metabolites added as potential interferents.The method exhibited favorable measurement performance,with a quantitation limit of 0.086 ng/mL,linear range of 0.1–400 ng/mL,a total imprecision of≤2.90%,spike recovery of 100.1%–100.6%,and relative deviations from assigned target values(RfB Institution)of−2.91%to 1.10%.The cRMP demonstrated good consistency with the conventional assay(chemiluminescence method),with a correlation coefficient R of 0.96977.Conclusion:A cRMP with high accuracy,cost-effectiveness,and convenient operation was developed for quantifying 17-OHP in serum.Its simplicity and robust performance make it an invaluable addition to the arsenal of analytical tools available for laboratories.This method can enhance the accuracy and reliability of 17-OHP measurements across various laboratories.展开更多
The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples rema...The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples remains challenging. Cr(VI) analyses with multipoint calibration and speciated isotope dilution (SID) adapted from U.S. EPA method 6800 were used to measure lower-level Cr(VI) on an ion chromatograph coupled with a tandem mass spectrometer (IC-MS/MS). Lake sediment samples were collected from various locations in Northern Ontario and Cr(VI) was extracted using both alkaline digestion and ethylene diaminetetraacetic acid (EDTA) extraction. Certified reference materials were extracted and analyzed by IC-MS/MS and UV-VIS detection. The SID-MS approach allowed for the quantification of Cr(VI) in samples with concentration levels below 0.5 μg.g-1 wet weight.展开更多
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This paper describes the quantitative determination of rare-earth elements cerium, dysprosium and non-rare-earth element copper, lead and the homogeneity examination of these four elements in yttrium oxide reference material by isotope dilution spark source mass spectrometry (ID-SSMS). The sensitivity of the meth- od is l0^(-5)～10^(-7%). The precision is better than 6%. The accuracy is better than 5%. The interferences of the spectra and the optimum amount of the spike added to the sample are discussed. The choice of the conducting material for the sample electrodes is studied.
基金Science and Technology Project of Dongguan,Grant/Award Number:20211800905072Graduate Education Innovation Program Project of Guangdong Province,Grant/Award Number:2022KCXTD010+6 种基金Discipline Construction Project of Guangdong Medical University,Grant/Award Numbers:4SG22098G,4SG22259G,4SG23030G,4SG23143GNational Natural Science Foundation of China,Grant/Award Numbers:81870016,82270013Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2022A1515010525Guangdong Medical UniversityShenzhen YHLO Biotech Co.,Ltd.Huazhong University of Science and TechnologyShenzhen Maternal and Child Health Care Hospital。
文摘Background:Accurate quantification of 17-hydroxyprogesterone(17-OHP)in serum is vital for clinical and research applications.However,inter-laboratory variability in test results exists owing to the lack of a standardized reference measurement procedure(RMP).Therefore,in this study,we developed a highly accurate,cost-effective,and user-friendly candidate RMP(cRMP)for analyzing 17-OHP in serum.Methods:We quantified 17-OHP in serum using a one-step liquid–liquid extraction method with the addition of 17-OHP-^(13)C_(3),followed by liquid chromatography–tandem mass spectrometry.The ability of these methods to suppress interference was evaluated by chromatographic analysis.We assessed accuracy,specificity,the lower limit of quantitation,linearity,and matrix effects by following the standards specified by the Clinical and Laboratory Standards Institute.The consistency between the developed cRMP and the chemiluminescence method was evaluated through experiments with 120 clinical samples.Results:The developed cRMP required only 8 min for accurate quantification of serum 17-OHP without bias from matrix effects or interference from 19 metabolites added as potential interferents.The method exhibited favorable measurement performance,with a quantitation limit of 0.086 ng/mL,linear range of 0.1–400 ng/mL,a total imprecision of≤2.90%,spike recovery of 100.1%–100.6%,and relative deviations from assigned target values(RfB Institution)of−2.91%to 1.10%.The cRMP demonstrated good consistency with the conventional assay(chemiluminescence method),with a correlation coefficient R of 0.96977.Conclusion:A cRMP with high accuracy,cost-effectiveness,and convenient operation was developed for quantifying 17-OHP in serum.Its simplicity and robust performance make it an invaluable addition to the arsenal of analytical tools available for laboratories.This method can enhance the accuracy and reliability of 17-OHP measurements across various laboratories.
文摘The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples remains challenging. Cr(VI) analyses with multipoint calibration and speciated isotope dilution (SID) adapted from U.S. EPA method 6800 were used to measure lower-level Cr(VI) on an ion chromatograph coupled with a tandem mass spectrometer (IC-MS/MS). Lake sediment samples were collected from various locations in Northern Ontario and Cr(VI) was extracted using both alkaline digestion and ethylene diaminetetraacetic acid (EDTA) extraction. Certified reference materials were extracted and analyzed by IC-MS/MS and UV-VIS detection. The SID-MS approach allowed for the quantification of Cr(VI) in samples with concentration levels below 0.5 μg.g-1 wet weight.
文摘提出了同位素稀释-液相色谱-串联质谱法测定鱼、虾、蟹、贝4类水产品中甲霜灵残留量的方法。取样品(5±0.05)g,加入10 ng的内标甲霜灵-d 6,静置10 min,用10 mL含1%(体积分数)乙酸的乙腈溶液涡旋混合、离心。取上清液,于45℃氮吹至0.5 mL以下,加入7.5 mL 20%(体积分数,下同)乙腈溶液混匀,用7.5 mL正己烷去脂,Agela Cleanert S C_(18)固相萃取柱富集净化。所得溶液于45℃氮吹至干,用1 mL 20%乙腈溶液复溶,混匀后过0.22μm针式水相尼龙滤膜,滤液收集至进样小瓶中。以SHISEIDO CAPCELL PAK C_(18)色谱柱为固定相,以不同体积比的0.1%(体积分数)甲酸溶液和乙腈的混合液为流动相进行梯度洗脱,内标法定量。结果表明,甲霜灵标准曲线的线性范围为1.0~100.0μg·L^(-1),检出限(3S/N)为0.5μg·kg^(-1)。以不同品种水产品为空白基质,在1.0,2.0,10.0μg·kg^(-1)等3个浓度水平下,甲霜灵的回收率为93.8%~105%,测定值的相对标准偏差(n=6)均小于13%。
