液相色谱-氢化物发生-原子荧光联用同时测定洛克沙胂及其代谢物

利用液相色谱-氢化物发生-原子荧光联用技术同时检测5种砷形态化合物(亚砷酸、砷酸、一甲基胂酸、二甲基胂酸和洛克沙胂).结果表明,在梯度洗脱条件下,以C18反相柱作分离柱,含0.5 mmol/L四丁基溴化铵的NaH2PO4-CH3OH溶液为流动相,5种砷化合物得以完全分离;以20 g/L K2S2O8为氧化剂进行紫外消解,7% HCl为载流,20 g/L KBH4为还原剂,砷化合物形成最佳的原子荧光信号.5种砷化合物在一定的浓度范围内与荧光峰面积呈良好的线性关系; 检出限＜10 μg/L; 加标回收率为81.4%～105.6%; 相对标准偏差RSD<4.0%.本方法适用于饲料、鸡粪、土壤和植物样品中洛克沙胂及其代谢物(亚砷酸、砷酸、一甲基胂酸和二甲基胂酸)的含量分析.     

人肝细胞中砷代谢产物分析表征研究

采用高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)联用技术对染砷后Chang肝细胞中的砷代谢产物进行分析.通过参考文献及相关实验推测出两种未知砷代谢产物,并采用标准合成加入法证明其中一种未知砷代谢产物为一甲基亚胂酸(MMAⅢ).定量分析结果显示,随着染砷浓度的增大,细胞中的-甲基砷、二甲基砷以及无机砷含量...     

日本遗弃化学武器污染土壤中砷的形态分析方法研究

土壤中无机砷的污染比较普遍,有机砷的污染情况比较特殊,处理日本遗弃在华化学武器(JACW)过程中与化学武器接触的土壤往往有机砷的污染比较严重,有时总砷含量超过国家标准的数十倍.为了查明污染的来源,必须砷的形态进行分析研究.本文在总砷含量测定的基础上,使用气相色谱-质谱(GC/MS)法对污染土壤砷的形态分析进行了研究,查明了东北某地被JACW污染的土壤中砷化合物的形态,主要含砷化合物为2-氯乙烯胂酸、双(2-氯乙烯基)胂酸、三(2-氯乙烯基)胂、三苯胂、笨胂酸和二苯胂酸等,为这些污染土壤的修复提供了技术数据.     

鱿鱼丝中砷的形态分析

采用电感耦合等离子体-质谱(ICP-MS)测定了14种鱿鱼丝(Dried Shredded Squid,DSS)中的砷总量,发现14种鱿鱼丝中的砷总量均低于2μg.g-1;用高效液相色谱(HPLC)与ICP-MS联用技术建立了As(Ⅲ)、As(Ⅴ)、二甲基胂酸(DMA)、甲基胂酸(MMA)、砷甜菜碱(AsB)和砷胆碱(AsC)六种砷形态的分离分析方法;采用快速溶剂萃取(ASE)、超声溶剂提取(SON)和盐酸浸提三种不同的前处理方法分析了3种鱿鱼丝中的砷形态,发现鱿鱼丝中的砷主要以AsB形式存在。     

树脂分离-氢化物发生-原子荧光光谱法测定食品中无机砷、一甲基胂和二甲基胂

建立了用阴离子交换树脂分离-氢化物发生原子荧光光谱法测定食品中无机砷、一甲基胂和二甲基胂的方法.分别从样品上样条件及二甲基胂、一甲基胂、 As(Ⅲ)和As(Ⅴ)分离条件进行了优化.研究了树脂处理程序对分离的影响,并探讨了共存离子对测定砷的干扰和消除的方法.对方法的适用范围做了研究.本方法具有操作简便、快速、灵敏度高等优点.检出限(以砷计)分别为: 无机砷0.34 μg/L,一甲基胂0.57 μg/L,二甲基胂0.46 μg/L.     

人肝细胞中甲基硫代砷酸的表征及其代谢过程的推测

利用高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)联用技术对染砷后Chang肝细胞中的砷代谢产物进行分析.借助合成标准,采用标准加入法,表征出肝细胞中一种未知砷代谢产物甲基硫代砷酸(MMTA).定量分析显示,MMTA含量随染砷浓度升高呈上升趋势.采用质量平衡分析法对双氧水处理前后的染砷细胞样品进行研究.结果显示,除小分子砷代谢产物外,细胞中部分砷代谢产物以大分子形态存在,推测其为砷蛋白类物质.由于MMTA系首次在人体肝细胞中发现,本研究结合实验现象和相关文献推测该物质系细胞代谢产物,并且其代谢途径与二甲基硫代砷酸相似,是以细胞内与其对应的一甲基亚砷酸为代谢起点.     

高效液相色谱-电感耦合等离子体质谱联用测定鸡肉及鸡肝中10种砷形态化合物

建立了一种有效分离检测鸡肉及鸡肝样品中洛克沙砷(ROX)、阿散酸(ASA)、硝苯胂酸(NPAA)、卡巴胂(CBS)、砷酸(AsⅤ)、亚砷酸(AsⅢ)、一甲基胂酸(MMA)、二甲基胂酸(DMA)、砷甜菜碱(As B)和砷胆碱(As C)共10种砷形态化合物的高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)分析方法。采用10%甲醇为提取液,碳酸铵溶液为流动相,以阴离子分析柱将样品提取液进行分离,最后进行ICP-MS测定。10种砷形态化合物在0.1~100μg/L范围内线性关系良好,相关系数(r2)均大于0.999,检出限为0.3~1.5μg/kg,定量下限为1.0~5.0μg/kg,加标回收率为81.3%~97.7%,相对标准偏差为0.1%~3.5%。该法重现性好、灵敏度高,且采用组织研磨仪机械振荡5 min即可成功提取10种砷形态化合物,与常规水浴加热振荡提取相比更加简便、高效。该法适用于鸡肉及鸡肝样品中10种砷形态化合物的同时检测,通过对实际样品的分析测定,在鸡肝样品中检出阿散酸和亚砷酸。     

方便面中砷元素的形态分析

建立了硝酸提取,高效液相色谱一原子荧光联用技术测定方便面中不同砷形态的分析方法。样品经0．15mol／L盐酸溶液超声提取后离心过滤,上机测试。实验表明：砷的4种形态亚砷酸[As（Ⅲ）]、砷酸[As（V）]、一甲基胂酸（MMA）和二甲基胂酸（DMA）的线性范围为0-50μg／L,相关系数（r）均优于0．9990,检出限在2～8μg／L之间,砷各形态的测量重复性（以RSD表示）均小于5％,样品的加标回收率为78％-118％。同时用原子荧光光度计检测了样品中总砷,并将两种方法测定结果进行了对比,结果符合理论以及文献报道。该方法操作简单快速、结果准确可靠,适用于方便面中砷形态的分析测定。     

液相色谱-氢化物发生原子荧光光谱法测定饲料中砷的形态

建立了饲料中亚砷酸盐(As~(3+))、砷酸盐(As~(5+))、一甲基砷酸(MMA)、二甲基砷酸(DMA)、对氨基苯胂酸(p-ASA)、羟基苯胂酸(4-OH)和洛克沙胂(ROX)共7种不同形态砷的高效液相色谱-氢化物发生原子荧光光谱(HPLC-HG-AFS)分析方法。饲料样品采用甲醇-水(1∶1,V/V)溶液提取,15 mmol/L(NH_4)_2HPO_4和10 mmol/L邻苯二甲酸氢钾为流动相,经PRP-X100阴离子交换色谱柱分离后,由HG-AFS测定。结果表明,7种砷形态标准曲线的线性关系良好(R2≥0.9964),方法检出限为5~30 μg/kg,平均回收率为76.3%~108.1%,日内相对标准偏差≤7.7%,日间相对标准偏差≤17.4%。本方法灵敏度高、前处理简单、运行费用低廉,适用于饲料产品中砷的形态分析。     

高效液相色谱-电感耦合等离子质谱法分析雄黄在大鼠脏器中代谢的砷形态

采用HPLC-ICP-MS联用技术建立了大鼠脏器中AsB,As?,MMA,DMA和As?等砷形态的分析方法。采用超声水浴提取对样品进行前处理,Dionex IonPac AS19阴离子交换柱,20 mmol/L(NH4)2CO3(pH 9.7)为流动相,对雄黄染毒后大鼠肝肾中的砷形态进行分析。实验表明,方法不受40Ar35Cl+干扰,常见的5种砷形态化合物的线性范围为1~300μg/L,相关系数(R2)均大于0.999,检出限为0.3~0.5(μg/L),RSD均小于5%,加标回收率为83.8%~111.7%。通过对肝肾的形态分析,表明经雄黄染毒后大鼠肝脏中的砷形态主要为DMA、As?和未知物2;肾脏中的砷形态主要为DMA、MMA、As?、未知物1、未知物2和未知物3。综合表明,此方法适用于雄黄代谢后的主要砷形态分析。     

Effect of realgar on extracellular amino acid neurotransmitters in hippocampal CA1 region determined by online microdialysis–dansyl chloride derivatization–high‐performance liquid chromatography and fluorescence detection

An online microdialysis (MD)–dansyl chloride (Dns) derivatization–high‐performance liquid chromatography (HPLC) and fluorescence detection (FD) system was developed for simultaneous determination of eight extracellular amino acid neurotransmitters in hippocampus. The MD probe was implanted in hippocampal CA1 region. Dialysate and Dns were online mixed and derivatized. The derivatives were separated on an ODS column and detected by FD. The developed online system showed good linearity, precision, accuracy and recovery. This online MD‐HPLC system was applied to monitor amino acid neurotransmitters levels in rats exposed to realgar (0.3, 0.9 and 2.7 g/kg body weight). The result shows that glutamate concentrations were significantly increased (p < 0.05) in hippocampal CA1 region of rats exposed to three doses of realgar. A decrease in γ‐aminobutyric acid concentrations was found in rats exposed to medium and high doses of realgar (p < 0.05). Elevation of excitotoxic index (EI) values in hippocampal CA1 region of realgar‐exposed rats was observed (p < 0.05). Positive correlation was found between EI values and arsenic contents in hippocampus of realgar‐exposed rats, which indicates that the change in extracellular EI values is associated with arsenic accumulation in hippocampus. The developed online MD–Dns derivatization–HPLC–FD system provides a new experimental method for studying the effect of toxic Chinese medicines on amino acid neurotransmitters. Copyright © 2014 John Wiley & Sons, Ltd.     

雄黄染毒后大鼠脑组织中氨基酸类神经递质含量的变化

研究了雄黄对大鼠脑组织氨基酸类神经递质含量的影响.将32只Wistar大鼠随机分为对照组(0.5%CMC-Na)以及低剂量(0.3g/kg)、中剂量(0.9g/kg)、高剂量(2.7g/kg)雄黄染毒组,通过连续灌胃给予雄黄混悬液两周.采用高效液相色谱-柱前衍生化法测定了大鼠脑组织中氨基酸类神经递质含量的变化.结果表明,与对照组比较,低剂量组大鼠脑组织中丝氨酸、甘氨酸和γ-氨基丁酸含量明显增加.中、高剂量组大鼠脑组织中同型半胱氨酸、谷氨酰胺、丝氨酸和天冬氨酸含量明显比对照组的低.总体而言,雄黄可对大鼠脑组织氨基酸类神经递质产生影响,氨基酸类神经递质可能是雄黄毒性作用的靶点之一.     

Optimization of microwave‐assisted extraction for six inorganic and organic arsenic species in chicken tissues using response surface methodology

Response surface methodology was applied to optimize the parameters for microwave‐assisted extraction of six major inorganic and organic arsenic species (As(III), As(V), dimethyl arsenic acid, monomethyl arsenic acid, p‐arsanilic acid, and roxarsone) from chicken tissues, followed by detection using a high‐performance liquid chromatography with inductively coupled mass spectrometry detection method, which allows the simultaneous analysis of both inorganic and organic arsenic species in the extract in a single run. Effects of extraction medium, solution pH, liquid‐to‐solid ratio, and the temperature and time of microwave‐assisted extraction on the extraction of the targeted arsenic species were studied. The optimum microwave‐assisted extraction conditions were: 100 mg of chicken tissue, extracted by 5 mL of 22% v/v methanol, 90 mmol/L (NH₄)₂HPO₄, and 0.07% v/v trifluoroacetic acid (with pH adjusted to 10.0 by ammonium hydroxide solution), ramping for 10 min to 71°C, and holding for 11 min. The method has good extraction performance for total arsenic in the spiked and nonspiked chicken tissues (104.0 ± 13.8% and 91.6 ± 7.8%, respectively), except for the ones with arsenic contents close to the quantitation limits. Limits of quantitation (S/N = 10) for As(III), As(V), dimethyl arsenic acid, monomethyl arsenic acid, p‐arsanilic acid, and roxarsone in chicken tissues using this method were 0.012, 0.058, 0.039, 0.061, 0.102, and 0.240 mg/kg (dry weight), respectively.     

Determination and pharmacokinetic properties of arsenic speciation in Xiao‐Er‐Zhi‐Bao‐Wan by high‐performance liquid chromatography with inductively coupled plasma mass spectrometry

A method of high performance liquid chromatography with a Hamilton PRP‐X100 ion‐exchange column (250 × 4.1 mm id, 10 μm) coupled to inductively coupled plasma mass spectrometry was employed to generate a full concentration–time profile of arsenic speciation after oral administration. The results exhibited good linearity and revealed that, in the pills, the average arsenic concentration was 10105.4 ± 380.7 mg/kg, and in the water extraction solution, the inorganic As(III) and As(V) concentrations were 220.1 ± 12.6 and 45.5 ± 2.3 mg/kg, respectively. No trace of monomethyl arsenic acid was detected in any of the plasma samples. We then successfully applied the established methodology to examine the pharmacokinetics of arsenic speciation. The resulting data revealed that, after oral administration in rats, the plasma concentration of each arsenic species reached C_max shortly after initial dosing, and that the distribution and elimination of As(V) was faster than that of As(III) and dimethyl arsenic acid. Additionally, the t_1/2 values of As(V), As(III), and dimethyl arsenic acid were 3.4 ± 1.6, 14.3 ± 4.0, and 19.9 ± 1.6 h, respectively. This study provides references for the determination of arsenic speciation in mineral‐containing medicines and could serve as a useful tool in measuring the true toxicity in traditional medicines that contain them.     

A method for rapid determination of arsenic species in vegetables using microwave‐assisted extraction followed by detection with HPLC hyphenated to inductively coupled plasma‐mass spectrometry

Driven by the significant need for characterization of the chemical speciation of arsenic in food, this work developed a method for rapid determination of four common arsenic species, namely, arsenite, arsenate, monomethyl arsenic acid, and dimethyl arsenic acid, in vegetables using microwave‐assisted extraction, followed by detection with high‐performance liquid chromatography hyphenated to inductively coupled plasma‐mass spectrometry. Initial screening results showed that microwave‐assisted extraction using 1% HNO₃ exhibited the highest overall efficiencies for all arsenic species without causing significant degradation of the organic ones. With the aid of response surface methodology, the optimum conditions established for extraction of arsenic species from vegetables were: 500 mg of freeze‐dried vegetable sample, extracted by closed vessel microwave‐assisted extraction using 10 mL of 2% v/v HNO₃ at 90°C for 17 min. Application of the method in the analysis of 24 market vegetable samples indicates that the extraction efficiencies for total arsenic species were in the range of 91.4–106%. Arsenite and arsenate were found to be the predominant arsenic species in the vegetables, which suggests that vegetable consumption could be an important route of inorganic arsenic exposure for the population with a heavy vegetable diet in arsenic polluted regions.     

Arsenic speciation based on ion exchange high-performance liquid chromatography hyphenated with hydride generation atomic fluorescence and on-line UV photo oxidation

An on-line method capable of the separation of arsenic species was developed for the speciation of arsenite As(III), arsenate As(V), monomethylarsenic (MMA) and dimethylarsenic acid (DMA) in biological samples. The method is based on the combination of high-performance liquid chromatograph (HPLC) for separation, UV photo oxidation for sample digestion and hydride generation atomic fluorescence spectrometry (HGAFS) for sensitive detection. The best separation results were obtained with an anion-exchange AS11 column protected by an AG11 guard column, and gradient elution with NaH2PO4 and water as mobile phase. The on-line UV photo oxidation with 1.5% K2S2O8 in 0.2 mol L(-1) NaOH in an 8 m PTFE coil for 40 s ensures the digestion of organoarsenic compounds. Detection limits for the four species were in the range of 0.11-0.15 ng (20 microL injected). Procedures were validated by analysis of the certified reference materials GBW09103 freeze-dried human urine and the results were in good agreement with the certified values of total arsenic concentration. The method has been successfully applied to speciation studies of blood arsenic species with no need of sample pretreatment. Speciation of arsenic in blood samples collected from two patients after the ingestion of realgar-containing drug reveals slight increase of arsenite and DMA, resulting from the digestion of realgar.     

HPLC-ICP-MS测定植物样品中6种砷形态化合物

通过优化色谱分离、样品前处理条件,同时对比了电感耦合等离子体质谱的标准模式(STD)、碰撞模式(KED)、氧气反应模式(Oxygen-DRC)、甲烷反应模式(Methane-DRC)的检测结果,建立了一种有效分离植物样品中砷甜菜碱(AsB)、二甲基砷酸(DMA)、亚砷酸(As(Ⅲ))、砷胆碱(AsC)、一甲基砷酸(MM...     

Enzymatic digestion and chromatographic analysis of arsenic species released from proteins

A method combining gel filtration chromatography (GFC), protease digestion, and ion pair chromatography with inductively coupled plasma mass spectrometry detection was developed for the determination of arsenic species bound to proteins. The method was first established by examining the interactions of two model proteins, metallothionein (MT) and hemoglobin, with three reactive trivalent arsenic species. It was then successfully applied to the speciation of arsenic in red blood cells of rats. Inorganic arsenite (iAs^III), monomethylarsonous acid (MMA^III), and dimethylarsinous acid (DMA^III) were efficiently released from the proteins by protease digestion at pH 8.0, with the recovery ranging from 93% to 106%. There was no oxidation of iAs^III or MMA^III during the protease digestion process. Up to 61% DMA^III (the least stable arsenic species) was unchanged, and the rest was oxidized to the pentavalent dimethylarsinic acid (DMA^V). The arsenic species in the red blood cells of control rats was present as DMA^III complex with hemoglobin. The method enabling the determination of the specific arsenic species that bind to cellular proteins is potentially useful for studying arsenic distribution, metabolism, and toxicity.     

Arsenic speciation based on ion exchange high-performance liquid chromatography hyphenated with hydride generation atomic fluorescence and on-line UV photo oxidation

An on-line method capable of the separation of arsenic species was developed for the speciation of arsenite As(III), arsenate As(V), monomethylarsenic (MMA) and dimethylarsenic acid (DMA) in biological samples. The method is based on the combination of high-performance liquid chromatograph (HPLC) for separation, UV photo oxidation for sample digestion and hydride generation atomic fluorescence spectrometry (HGAFS) for sensitive detection. The best separation results were obtained with an anion-exchange AS11 column protected by an AG11 guard column, and gradient elution with NaH₂PO₄ and water as mobile phase. The on-line UV photo oxidation with 1.5% K₂S₂O₈ in 0.2 mol L^–1 NaOH in an 8 m PTFE coil for 40 s ensures the digestion of organoarsenic compounds. Detection limits for the four species were in the range of 0.11–0.15 ng (20 μL injected). Procedures were validated by analysis of the certified reference materials GBW09103 freeze-dried human urine and the results were in good agreement with the certified values of total arsenic concentration. The method has been successfully applied to speciation studies of blood arsenic species with no need of sample pretreatment. Speciation of arsenic in blood samples collected from two patients after the ingestion of realgar-containing drug reveals slight increase of arsenite and DMA, resulting from the digestion of realgar.     

Analysis and leaching characteristics of mercury and arsenic in Chinese medicinal material

The purpose of this study is to investigate the amounts and characteristics of heavy metals (As, Hg) leachable from several Chinese medicinal materials (CMM) under conditions simulating stomach and intestine digestion and absorption. Analysis by inductively coupled plasma mass spectrometry (ICP-MS) was compared with that by hydride generation atomic fluorescence spectrometry (HG-AFS). Focused microwave assisted extraction (MAE) and Soxhlet extraction were carried out to compare with the conventional sequential extraction method. The CMM studied included two mineral drugs: realgar and cinnabar, and two formulated drugs containing the two minerals. The leachable amounts of the target elements into artificial stomach fluid, artificial intestinal fluid, and artificial intestinal fluid in 0.5% trypsin were compared. The last solvent gave the greatest amounts of leachable As (0.41%) from realgar and Hg (1×10⁻⁴%) from cinnabar, but otherwise no significant effect on the leachable amounts was observed upon changing the following parameters: temperature (37-60 °C), HCl concentration (0.5-6 M), and CMM sample particle size (74 and 250 μm). The low leaching efficiencies observed confirmed the presence of As and Hg as insoluble species (sulfides)in these mineral drugs. Sequential extraction schemes were used to determine the species of mercury and arsenic in formulated drugs containing the minerals. Trace amounts of organic forms of arsenic (0.43%) and mercury (2.9×10⁻⁴%) were observed which could be the transformation products derived from the original cinnabar or realgar minerals in drug formulation.