[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived f...[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food.展开更多
The accurate and efficient measurement of small molecule disease markers for clinical diagnosis is of great importance.In this study,a quadrupole-linear ion trap(Q-LIT)tandem mass spectrometer was designed and built i...The accurate and efficient measurement of small molecule disease markers for clinical diagnosis is of great importance.In this study,a quadrupole-linear ion trap(Q-LIT)tandem mass spectrometer was designed and built in our laboratory.Target precursor ions were first selected in the quadrupole,and then injected,trapped,and fragmented simultaneously in the linear ion trap(LIT)to reduce the space charge effect,enrich the target product ions,and promote sensitivity.The targeted analytes were measured with selected reaction monitoring using a positive scan mode with electrospray ionization(ESI).Ions with a mass-to-charge ratio(m/z)ranging from 195 to 2022 were demonstrated.When scanning at 1218amu.s^(-1),unit resolution and an accuracy of higher than m/z 0.28 was obtained for m/z up to 2000.The dimensionless Mathieu parameter(q)value used in this study was 0.40 for collision-induced dissociation(CID),which was activated by resonance excitation.And an overall CID efficiency of 64%was achieved(activation time,50 ms).Guanidinoacetic acid(GAA)and creatine(CRE)were used as model compounds for small molecule clinical biomarkers.The limits of quantification were 1.0 and 0.2 nmol.L^(-1)for GAA and CRE,respectively.A total of 77 actual samples were successfully analyzed by the home-built ESI-Q-LIT tandem mass spectrometry system.The developed method can reduce matrix interference,minimize space charge effects,and avoid the chromatographic separation of complex samples to simplify the pretreatment process.This novel Q-LIT system is expected to be a good candidate for the determination of biomarkers in clinical diagnosis and therapeutics.展开更多
The 27Al＋ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it canno...The 27Al＋ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it cannot be laser-cooled directly in the absence of 167nm laser to date. This problem can be solved by sympathetic cooling. In this work, a linear Paul trap is used to trap both 40Ca＋ and 27A1＋ ions simultaneously, and a single Dopplercooled 40Ca＋ ion is employed to sympathetically cool a single 27A1＋ ion. Thus a ＇bright-dark＇ two-ion crystal has been successfully synthesized. The temperature of the crystal has been estimated to be about 7mK by measuring the ratio of carrier and sideband spectral intensities. Finally, the dark ion is proved to be an 27Al＋ ion by precise measuring of the ion crystal＇s secular motion frequency, which means that it is a great step for our 2Z Al＋ quantum logic clock.展开更多
We propose a practical scheme to generate cluster states by simultaneously accomplishing two-qubit conditional gating on an array of equidistant ions by using transverse modes. Our operation is robust to heating and i...We propose a practical scheme to generate cluster states by simultaneously accomplishing two-qubit conditional gating on an array of equidistant ions by using transverse modes. Our operation is robust to heating and insensitive to Lamb-Dicke parameter. Meanwhile, as it is carried out in a geometric quantum computing fashion, our scheme enables the fast and high-fidelity generation of cluster states. The experimental feasibility is discussed with sophisticated ion trap techniques.展开更多
The 7Li＋ ion is one of the most important candidates for verifying QED theory and obtaining the precise value of the fine-structure constant ~. However, direct laser cooling of trapped Li＋ ions will lead to strong b...The 7Li＋ ion is one of the most important candidates for verifying QED theory and obtaining the precise value of the fine-structure constant ~. However, direct laser cooling of trapped Li＋ ions will lead to strong background fluorescence which will influence the spectrum detection. The sympathetic cooling technique is a good choice to solve the problem. In this work, we report sympathetic cooling of 7 Li＋ ions to few mK using 40Ca＋ ions in a linear Paul trap. A mixed ion crystal of 40Ca＋ ions and 7Li＋ ions are obtained. We also analyze the motion frequency spectra of pure 40 Ca＋ ions and mixed ions.展开更多
目的基于高效液相色谱-三重四极杆/复合线性离子阱质谱法(high performance liquid chromatography-triple quadrupole/composite linear ion trap mass spectrometry,HPLC-QTRAP MS)建立同时测定液态发酵食品中14中生物胺及其代谢物的...目的基于高效液相色谱-三重四极杆/复合线性离子阱质谱法(high performance liquid chromatography-triple quadrupole/composite linear ion trap mass spectrometry,HPLC-QTRAP MS)建立同时测定液态发酵食品中14中生物胺及其代谢物的分析方法。方法采用Waters Atlantis Premier BEH Z-HILIC色谱柱(100mm×2.1mm,1.7μm),以0.025%(V/V)甲酸水和0.1%(V/V)甲酸乙腈进行梯度洗脱,电喷雾离子源(electrospray ionization,ESI)正离子模式、多反应监测(multiple reaction monitoring,MRM)离子扫描模式、信息依赖性采集(information dependent acquisition,IDA)、增强子离子扫描(enhanced ion scanning,EPI)和EPI谱库搜索的复合模式进行测定。结果在0.05~200.00μg/L质量浓度范围内,14种生物胺及其代谢物的线性关系良好,相关系数均大于0.99;方法检出限(S/N=3)为0.15~6.00μg/L;在不同添加质量浓度(2.0、10.0、50.0μg/L)下,其回收率为75.2%~107.9%,相对标准偏差在1.98%~9.07%之间。结论该方法具有操作简便、快速、准确、灵敏等优点,可满足液态类发酵食品中14种生物胺的定性定量分析需要,为液态发酵类食品中生物胺的检测分析奠定基础。展开更多
基金Supported by Scientific Research Project of Dalian Customs(2022DK09).
文摘[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food.
基金financially supported by the National Key R&D Program of China(2018YFF0212503,2019YFF0216303,and 2016YFF0200502)the National Natural Science Foundation of China(21927812)the Research Project of the National Institute of Metrology(AKY1934)。
文摘The accurate and efficient measurement of small molecule disease markers for clinical diagnosis is of great importance.In this study,a quadrupole-linear ion trap(Q-LIT)tandem mass spectrometer was designed and built in our laboratory.Target precursor ions were first selected in the quadrupole,and then injected,trapped,and fragmented simultaneously in the linear ion trap(LIT)to reduce the space charge effect,enrich the target product ions,and promote sensitivity.The targeted analytes were measured with selected reaction monitoring using a positive scan mode with electrospray ionization(ESI).Ions with a mass-to-charge ratio(m/z)ranging from 195 to 2022 were demonstrated.When scanning at 1218amu.s^(-1),unit resolution and an accuracy of higher than m/z 0.28 was obtained for m/z up to 2000.The dimensionless Mathieu parameter(q)value used in this study was 0.40 for collision-induced dissociation(CID),which was activated by resonance excitation.And an overall CID efficiency of 64%was achieved(activation time,50 ms).Guanidinoacetic acid(GAA)and creatine(CRE)were used as model compounds for small molecule clinical biomarkers.The limits of quantification were 1.0 and 0.2 nmol.L^(-1)for GAA and CRE,respectively.A total of 77 actual samples were successfully analyzed by the home-built ESI-Q-LIT tandem mass spectrometry system.The developed method can reduce matrix interference,minimize space charge effects,and avoid the chromatographic separation of complex samples to simplify the pretreatment process.This novel Q-LIT system is expected to be a good candidate for the determination of biomarkers in clinical diagnosis and therapeutics.
基金Supported by the National High Technology Research and Development Program of China under Grant No 2012AA120701the National Natural Science Foundation of China under Grant No 11174326
文摘The 27Al＋ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it cannot be laser-cooled directly in the absence of 167nm laser to date. This problem can be solved by sympathetic cooling. In this work, a linear Paul trap is used to trap both 40Ca＋ and 27A1＋ ions simultaneously, and a single Dopplercooled 40Ca＋ ion is employed to sympathetically cool a single 27A1＋ ion. Thus a ＇bright-dark＇ two-ion crystal has been successfully synthesized. The temperature of the crystal has been estimated to be about 7mK by measuring the ratio of carrier and sideband spectral intensities. Finally, the dark ion is proved to be an 27Al＋ ion by precise measuring of the ion crystal＇s secular motion frequency, which means that it is a great step for our 2Z Al＋ quantum logic clock.
基金supported by the National Natural Science Foundation of China (Grant Nos.10774163 and 10804132)
文摘We propose a practical scheme to generate cluster states by simultaneously accomplishing two-qubit conditional gating on an array of equidistant ions by using transverse modes. Our operation is robust to heating and insensitive to Lamb-Dicke parameter. Meanwhile, as it is carried out in a geometric quantum computing fashion, our scheme enables the fast and high-fidelity generation of cluster states. The experimental feasibility is discussed with sophisticated ion trap techniques.
基金Supported by the National Basic Research Program of China under Grant No 2010CB832803the National Natural Science Foundation of China under Grant Nos 11004222 and 91121016the Chinese Academy of Sciences
文摘The 7Li＋ ion is one of the most important candidates for verifying QED theory and obtaining the precise value of the fine-structure constant ~. However, direct laser cooling of trapped Li＋ ions will lead to strong background fluorescence which will influence the spectrum detection. The sympathetic cooling technique is a good choice to solve the problem. In this work, we report sympathetic cooling of 7 Li＋ ions to few mK using 40Ca＋ ions in a linear Paul trap. A mixed ion crystal of 40Ca＋ ions and 7Li＋ ions are obtained. We also analyze the motion frequency spectra of pure 40 Ca＋ ions and mixed ions.
文摘目的基于高效液相色谱-三重四极杆/复合线性离子阱质谱法(high performance liquid chromatography-triple quadrupole/composite linear ion trap mass spectrometry,HPLC-QTRAP MS)建立同时测定液态发酵食品中14中生物胺及其代谢物的分析方法。方法采用Waters Atlantis Premier BEH Z-HILIC色谱柱(100mm×2.1mm,1.7μm),以0.025%(V/V)甲酸水和0.1%(V/V)甲酸乙腈进行梯度洗脱,电喷雾离子源(electrospray ionization,ESI)正离子模式、多反应监测(multiple reaction monitoring,MRM)离子扫描模式、信息依赖性采集(information dependent acquisition,IDA)、增强子离子扫描(enhanced ion scanning,EPI)和EPI谱库搜索的复合模式进行测定。结果在0.05~200.00μg/L质量浓度范围内,14种生物胺及其代谢物的线性关系良好,相关系数均大于0.99;方法检出限(S/N=3)为0.15~6.00μg/L;在不同添加质量浓度(2.0、10.0、50.0μg/L)下,其回收率为75.2%~107.9%,相对标准偏差在1.98%~9.07%之间。结论该方法具有操作简便、快速、准确、灵敏等优点,可满足液态类发酵食品中14种生物胺的定性定量分析需要,为液态发酵类食品中生物胺的检测分析奠定基础。
