[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by ga...[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton.展开更多
The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides...The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.展开更多
[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
In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy...In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy of current methods approaches this limit, further exploration of new prediction techniques may become redundant. Conversely, a need for more precise prediction methods or models may be indicated. In this study, we have experimentally analyzed the limits of accuracy at different numbers of ions and parameters using repeated spectral pairs and integrating various similarity metrics. Results show significant achievements in accuracy for backbone ion methods with room for improvement. In contrast, full-spectrum prediction methods exhibit greater potential relative to the theoretical accuracy limit. Additionally, findings highlight the significant impact of normalized collision energy and instrument type on prediction accuracy, underscoring the importance of considering these factors in future theoretical tandem mass spectrometry predictions.展开更多
Introduction: On the 5<sup>th</sup> of June 2022, an incident of a mass attack following multiple gunshots and explosions occurred in a community in Ondo State Nigeria. This study aims to assess the mental...Introduction: On the 5<sup>th</sup> of June 2022, an incident of a mass attack following multiple gunshots and explosions occurred in a community in Ondo State Nigeria. This study aims to assess the mental health status of victims of the mass attack to guide further interventions among them. Methods: A cross-sectional study was conducted among victims of a mass attack in Owo community, Ondo State. A total of 209 affected victims were interviewed on socio-demographic characteristics, symptoms of anxiety (AD) and post-traumatic stress disorder (PTSD), threat experienced, and mental health support received. A 7-item Generalized Anxiety Disorder (GAD-7) and 9-item Post Traumatic Stress Disorder (PTSD) scale were used to assess the mental health status of the victims. A point was assigned to respondents who reported the symptoms of GAD, with a maximum score of 7 attained. For GAD, scores were categorized as follows: 1 - 2 as mild, 2 - 3 as minimal, 4 - 5 as moderate and 6 - 7 as severe. The PTSD symptoms were rated using a 5-point Likert scale response, and assigned the following points;4 = extremely, 3 = quite a bit, 2 = moderate, 1 = a little bit and 0 = not at all. From a maximum score of 36, participants with scores 18 and above were categorized as those with provisional PTSD. The independent samples t-test and correlational analysis were used to determine the association between PTSD score and other independent variables, with an alpha level of significance set at 0.05. Results: Generally, 38 (18.2%) of the respondents had severe AD. About half (89;42.6%) were categorized as those with provisional PTSD. The mean level of both AD (3.40 ± 2.26) and PTSD (16.51 ± 7.63) score is higher among those who were married compared to those not married (anxiety disorder;2.52 ± 2.20, P = 0.005 and PTSD;13.20 ± 8.86, P = 0.004). Respondents who have been counseled by a healthcare worker had a higher mean level (15.89 ± 7.58) of provisional PTSD compared to those not counseled by a healthcare worker (13.56 ± 9.22, P = 0.046). The level of PTSD score increased with a higher age group (r = 0.21, P = 0.003). Conclusions: The results show that the mass attack had psychological consequences among a high proportion of the victims, particularly, those married and in the older age groups. This suggests the need for continuous supportive counseling targeting these affected groups, and considering other factors moderating the effectiveness of counseling among them in future interventions.展开更多
Pesticide residue detection is an important work to ensure the quality safety of agricultural products.In the process of agricultural production,in order to prevent and control agricultural diseases and pests,a certai...Pesticide residue detection is an important work to ensure the quality safety of agricultural products.In the process of agricultural production,in order to prevent and control agricultural diseases and pests,a certain amount of pesticides need to be used.However,if pesticides are used excessively,there will be certain pesticide residues in crops and related products.Therefore,it is necessary to do a good job in pesticide residue detection.The gas chromatography-mass spectrometry(GC-MS)and liquid chromatography-mass spectrometry(LC-MS)detection methods have good results and can effectively detect pesticide residues in related products.This paper reviewed and analyzed the application of GC-MS and LC-MS in pesticide residue detection,and proposed optimization measures based on practical experience,hoping to provide reference for relevant scholars.展开更多
Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic geochemistry.It is the only approach to capture biomarker features of organic matter and provide...Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic geochemistry.It is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity determination.However,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this method.To overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,China.In this way,the mass chromatogram can be automatically interpreted.This research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(i.e.MI and PMI)that represent the organic matter thermal maturity and parent material type,respectively.Subsequently,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2values typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,respectively.The significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies.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
BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.neg...BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development.展开更多
[Objective] The inductively coupled plasma mass spectrometry(ICP-MS)was constructed to determine the contents of lead,cadmium,mercury and arsenic in Archyranthes bidentata Blume.[Method]Under the optimum operation con...[Objective] The inductively coupled plasma mass spectrometry(ICP-MS)was constructed to determine the contents of lead,cadmium,mercury and arsenic in Archyranthes bidentata Blume.[Method]Under the optimum operation condition of ICP-MS,the samples were digested by microwave.The element 114In was taken as an internal standard element to compensate body effect and ICP-MS method was used to determine the contents of lead,cadmium,mercury and arsenic.[Result]For the determined elements,the correlation coefficient(r)of standard curve was over 0.9995 and recovery rate was from 96.7% to 106.4% while RSD was less than 11.2%.The result of determination showed that the heavy metal content in Archyranthes bidentata Blume.beyond standard was serious.[Conclusion]The constructed ICP-MS method with simple operation,rapid response,accuracy and high sensitivity in this experiment could be used for quality control of Chinese medicinal materials by detecting heavy metal contents in different Chinese medicinal materials from original places.展开更多
目的评估自动化磁珠法提取血清脂溶性维生素应用液相色谱串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)检测的性能。方法收集200例临床剩余血清样本,采用自动化磁珠法提取血清中脂溶性维生素A,D_(2),D_(3),E和K...目的评估自动化磁珠法提取血清脂溶性维生素应用液相色谱串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)检测的性能。方法收集200例临床剩余血清样本,采用自动化磁珠法提取血清中脂溶性维生素A,D_(2),D_(3),E和K;同时联合LC-MS/MS检测脂溶性维生素A,D_(2),D_(3),E和K的线性、定量限、精密度、正确度、携带污染率等性能指标以及基质效应。并比较此方法与传统萃取法检测结果的一致性。结果自动化磁珠法提取脂溶性维生素A,D_(2),D_(3),E和K线性相关系数均>0.99;五种物质的定量限分别为5,0.25,0.25,125和0.025ng/ml;批内精密度和批间精密度分别为0.66%~4.83%,0.15%~3.70%;平均加标回收率为87.05%~111.11%;基质效应为95.43%~99.07%;高-低值样本循环进样结果均值与低-低值样本循环进样结果均值之差,均小于低-低值样本循环进样结果均值的3s;统计学结果显示自动化磁珠法和传统萃取法提取的脂溶性维生素结果相关性良好(r>0.99),两种方法的检测结果无显著偏倚。结论自动化磁珠法提取脂溶性维生素的检测性能良好,有望提高样品通量和分析效率。展开更多
基金Supported by The Fourth Batch of High-end Talent Project in Hebei Province.
文摘[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton.
基金supported by the National Natural Science Foundation of China(Nos.12125509,12222514,11961141003,and 12005304)National Key Research and Development Project(No.2022YFA1602301)+1 种基金CAST Young Talent Support Planthe CNNC Science Fund for Talented Young Scholars Continuous support for basic scientific research projects。
文摘The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.
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.
文摘In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy of current methods approaches this limit, further exploration of new prediction techniques may become redundant. Conversely, a need for more precise prediction methods or models may be indicated. In this study, we have experimentally analyzed the limits of accuracy at different numbers of ions and parameters using repeated spectral pairs and integrating various similarity metrics. Results show significant achievements in accuracy for backbone ion methods with room for improvement. In contrast, full-spectrum prediction methods exhibit greater potential relative to the theoretical accuracy limit. Additionally, findings highlight the significant impact of normalized collision energy and instrument type on prediction accuracy, underscoring the importance of considering these factors in future theoretical tandem mass spectrometry predictions.
文摘Introduction: On the 5<sup>th</sup> of June 2022, an incident of a mass attack following multiple gunshots and explosions occurred in a community in Ondo State Nigeria. This study aims to assess the mental health status of victims of the mass attack to guide further interventions among them. Methods: A cross-sectional study was conducted among victims of a mass attack in Owo community, Ondo State. A total of 209 affected victims were interviewed on socio-demographic characteristics, symptoms of anxiety (AD) and post-traumatic stress disorder (PTSD), threat experienced, and mental health support received. A 7-item Generalized Anxiety Disorder (GAD-7) and 9-item Post Traumatic Stress Disorder (PTSD) scale were used to assess the mental health status of the victims. A point was assigned to respondents who reported the symptoms of GAD, with a maximum score of 7 attained. For GAD, scores were categorized as follows: 1 - 2 as mild, 2 - 3 as minimal, 4 - 5 as moderate and 6 - 7 as severe. The PTSD symptoms were rated using a 5-point Likert scale response, and assigned the following points;4 = extremely, 3 = quite a bit, 2 = moderate, 1 = a little bit and 0 = not at all. From a maximum score of 36, participants with scores 18 and above were categorized as those with provisional PTSD. The independent samples t-test and correlational analysis were used to determine the association between PTSD score and other independent variables, with an alpha level of significance set at 0.05. Results: Generally, 38 (18.2%) of the respondents had severe AD. About half (89;42.6%) were categorized as those with provisional PTSD. The mean level of both AD (3.40 ± 2.26) and PTSD (16.51 ± 7.63) score is higher among those who were married compared to those not married (anxiety disorder;2.52 ± 2.20, P = 0.005 and PTSD;13.20 ± 8.86, P = 0.004). Respondents who have been counseled by a healthcare worker had a higher mean level (15.89 ± 7.58) of provisional PTSD compared to those not counseled by a healthcare worker (13.56 ± 9.22, P = 0.046). The level of PTSD score increased with a higher age group (r = 0.21, P = 0.003). Conclusions: The results show that the mass attack had psychological consequences among a high proportion of the victims, particularly, those married and in the older age groups. This suggests the need for continuous supportive counseling targeting these affected groups, and considering other factors moderating the effectiveness of counseling among them in future interventions.
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)+1 种基金Special Project of the Central Government in Guidance of Local Science and Technology Development(226Z5504G)Tangshan Talent Project(A202202005).
文摘Pesticide residue detection is an important work to ensure the quality safety of agricultural products.In the process of agricultural production,in order to prevent and control agricultural diseases and pests,a certain amount of pesticides need to be used.However,if pesticides are used excessively,there will be certain pesticide residues in crops and related products.Therefore,it is necessary to do a good job in pesticide residue detection.The gas chromatography-mass spectrometry(GC-MS)and liquid chromatography-mass spectrometry(LC-MS)detection methods have good results and can effectively detect pesticide residues in related products.This paper reviewed and analyzed the application of GC-MS and LC-MS in pesticide residue detection,and proposed optimization measures based on practical experience,hoping to provide reference for relevant scholars.
基金financially supported by China Postdoctoral Science Foundation(Grant No.2023M730365)Natural Science Foundation of Hubei Province of China(Grant No.2023AFB232)。
文摘Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic geochemistry.It is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity determination.However,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this method.To overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,China.In this way,the mass chromatogram can be automatically interpreted.This research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(i.e.MI and PMI)that represent the organic matter thermal maturity and parent material type,respectively.Subsequently,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2values typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,respectively.The significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies.
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BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development.
基金Supported by the National Science Foundation for Post-doctoral Scientists of China(20070410616)Excellent Youth Foundation of He'nan Scientific Committee(074100510018)~~
文摘[Objective] The inductively coupled plasma mass spectrometry(ICP-MS)was constructed to determine the contents of lead,cadmium,mercury and arsenic in Archyranthes bidentata Blume.[Method]Under the optimum operation condition of ICP-MS,the samples were digested by microwave.The element 114In was taken as an internal standard element to compensate body effect and ICP-MS method was used to determine the contents of lead,cadmium,mercury and arsenic.[Result]For the determined elements,the correlation coefficient(r)of standard curve was over 0.9995 and recovery rate was from 96.7% to 106.4% while RSD was less than 11.2%.The result of determination showed that the heavy metal content in Archyranthes bidentata Blume.beyond standard was serious.[Conclusion]The constructed ICP-MS method with simple operation,rapid response,accuracy and high sensitivity in this experiment could be used for quality control of Chinese medicinal materials by detecting heavy metal contents in different Chinese medicinal materials from original places.
文摘目的评估自动化磁珠法提取血清脂溶性维生素应用液相色谱串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)检测的性能。方法收集200例临床剩余血清样本,采用自动化磁珠法提取血清中脂溶性维生素A,D_(2),D_(3),E和K;同时联合LC-MS/MS检测脂溶性维生素A,D_(2),D_(3),E和K的线性、定量限、精密度、正确度、携带污染率等性能指标以及基质效应。并比较此方法与传统萃取法检测结果的一致性。结果自动化磁珠法提取脂溶性维生素A,D_(2),D_(3),E和K线性相关系数均>0.99;五种物质的定量限分别为5,0.25,0.25,125和0.025ng/ml;批内精密度和批间精密度分别为0.66%~4.83%,0.15%~3.70%;平均加标回收率为87.05%~111.11%;基质效应为95.43%~99.07%;高-低值样本循环进样结果均值与低-低值样本循环进样结果均值之差,均小于低-低值样本循环进样结果均值的3s;统计学结果显示自动化磁珠法和传统萃取法提取的脂溶性维生素结果相关性良好(r>0.99),两种方法的检测结果无显著偏倚。结论自动化磁珠法提取脂溶性维生素的检测性能良好,有望提高样品通量和分析效率。