Simultaneous analysis of several synthetic cannabinoids,THC, CBD and CBN,in hair by ultra‐high performance liquid chromatography tandem mass spectrometry. Method validation and application to real samples

A simple procedure for the quantitative detection of JWH‐018, JWH‐073, JWH 200, JWH‐250, HU‐210, Δ⁹‐tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN) in hair has been developed and fully validated. After digestion with NaOH and liquid–liquid extraction, the separation was performed with an ultra‐high performance liquid chromatography system coupled to a triple quadrupole mass spectrometer operating in the selected reaction monitoring mode. The absence of matrix interferents, together with excellent repeatability of both retention times and relative abundances of diagnostic transitions, allowed the correct identification of all analytes tested. The method was linear in two different intervals at low and high concentration, with correlation coefficient values between 0.9933 and 0.9991. Quantitation limits ranged from 0.07 pg/mg for JWH‐200 up to 18 pg/mg for CBD The present method for the determination of several cannabinoids in hair proved to be simple, fast, specific and sensitive. The method was successfully applied to the analysis of 179 real samples collected from proven consumers of Cannabis, among which 14 were found positive to at least one synthetic cannabinoid. Copyright © 2012 John Wiley & Sons, Ltd.     

Determination of cyantraniliprole and its major metabolite residues in vegetable and soil using ultra-performance liquid chromatography/tandem mass spectrometry

A rapid, highly sensitive and selective method was developed for the determination of the cyantraniliprole and its major metabolite J9Z38 in cucumber, tomato and soil by ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS). Target compounds were extracted with acetonitrile and an aliquot cleaned with primary and secondary amine. Two pairs of precursor product ion transitions for cyantraniliprole and J9Z38 were measured and evaluated. Average recoveries for cucumber, tomato and soil at three levels (10, 50 and 100 µg/kg) ranged from 74.7 to 96.2% with intra‐day relative standard deviation (RSD) of 2.6–15.1% and inter‐day RSD of 3.4–13.3%. The limit of quantitation for cyantraniliprole and J9Z38 were determined to be 5 and 10 µg/kg in samples (cucumber, tomato and soil), respectively. This method was used to determine the cyantraniliprole and J9Z38 residues in real cucumber, tomato and soil samples for studies on their dissipation. The trial results showed that the half‐lives of cyantraniliprole obtained after treatments were 2.2, 2.8 and 9.5 days in cucumber, tomato and soil in Zhejiang, respectively, and that the average levels of cyantraniliprole and J9Z38 residues in cucumber and tomato were all <0.01 mg/kg with the interval of 10 days after treatment. Copyright © 2011 John Wiley & Sons, Ltd.     

人参中农药多残留的超高效液相色谱-串联质谱分析方法研究

以传统中药人参为研究对象, 建立一种同时检测人参中46 种农药多残留的基质固相分散-超高效液相色谱-串联质谱(MSPD-UPLC-MS/MS)方法. 前处理方法分别采用N-丙基乙二胺(PSA)和乙腈作为MSPD的分散剂和洗脱剂, 检测方法采用正负离子同时扫描, 利用超高效液相色谱-串联质谱在分时段多反应监测模式下进行定量和定性分析. 大部分农药在5～500 μg/kg 范围内线性关系良好, 在低(10 μg/kg)、中(50 μg/kg)、高(100 μg/kg)三个浓度水平上的添加回收率平均值在70%～110%之间, 相对标准偏差(RSD)小于15% (n＝3), 定量限小于0.01 mg/kg, 能够满足农药多残留分析要求. 该方法通用性强、选择性好、灵敏度高、简单廉价.     

超高效液相色谱-四极杆-飞行时间质谱同时筛查腐败血液中24种农药

利用超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF-MS)技术建立了腐败血液中24种常见投毒农药的快速筛查方法。采用Qu ECh ERS方法进行样品前处理。腐败血液经乙腈-水(4∶1)提取,同时加入无水硫酸镁脱水,超声后过0.22μm滤膜后直接测定。目标药物经ACQUITY UPLCTMHSS C18柱分离,以乙腈和0.1%甲酸-甲酸铵水溶液为流动相进行梯度洗脱,采用正离子全信息串联质谱扫描模式(MSE)进行筛查。结果表明,腐败血液中24种农药的检出限(LOD,S/N=3)为0.43~10.0 ng/m L;3个加标水平下的平均回收率为61%~98%,相对标准偏差(RSD)为1.5%~16.9%。该方法快速简便、灵敏度较高,可用于腐败血液中24种常见投毒农药的快速筛查。     

超高效液相色谱-四极杆飞行时间质谱法快速筛查水产品中15种碱性合成色素

建立了超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF MS)快速检测水产品中15种碱性合成色素的方法。水产样品经乙腈(含10%(v/v)乙酸)提取,采用C₁₈复合硅胶基质分散管进行样品净化处理。目标物采用C₁₈色谱柱分离,以乙腈和0.1%(v/v)甲酸-5 mmol/L乙酸铵溶液为流动相,梯度洗脱,四极杆飞行时间串联质谱电喷雾正离子模式检测。结果表明:15种碱性色素的定量限(LOQs, S/N=10)为0.1~100 μg/kg,并在各自的线性范围内线性关系良好,相关系数(r)≥0.993。在3个加标水平下的平均回收率为80.60%~107.37%,测定结果的相对标准偏差为3.33%~6.69%(n=6)。该方法快速、简便、灵敏度高,适用于日常水产品中15种碱性合成色素的快速筛查。     

分散固相萃取净化-超高效液相色谱-串联质谱法测定鸡蛋和鸡肉中金刚烷胺和金刚乙胺残留

建立了鸡蛋和鸡肉中金刚烷胺和金刚乙胺残留量的分散固相萃取-超高效液相色谱-串联质谱测定方法。鸡蛋和鸡肉样品经氨水-乙腈(2 : 98, v/v)提取后,提取液经氮气吹干至1 mL后,利用C18和NH₂填料进行分散固相萃取净化,过滤膜后分析。采用ZORBAX C18色谱柱分离,用1 mmol/L乙酸铵水溶液(含0.1%(v/v)甲酸)-甲醇作为流动相进行梯度洗脱,正离子多反应监测模式。结果表明,金刚烷胺和金刚乙胺在0.15~10.0 μ g/L范围内具有较好的线性关系,鸡蛋和鸡肉中的检出限均为0.05 μ g/kg,定量限均为0.20 μ g/kg。当2种药物在鸡蛋和鸡肉中的加标水平为0.2、1.0和2.0 μ g/kg时,平均回收率范围为89%~108%,相对标准偏差范围为5.0%~8.6%。该方法能够满足鸡蛋和鸡肉中金刚烷胺和金刚乙胺残留量分析的要求。     

Double-ion imprinted polymer @magnetic nanoparticles modified screen printed carbon electrode for simultaneous analysis of cerium and gadolinium ions

A typical, reproducible, and rugged screen printed carbon electrode, modified with dual-ion imprinted beads, was fabricated employing the “surface grafting from” approach. For this, the acyl chloride functionalized magnetic nanoparticles were first immobilized and chemically attached with a typical functional monomer (but-2-enedioic acid bis-[(2-amino-ethyl)-amide]) on the electrode surface. This was subsequently subjected to the thermal polymerization in the presence of template ions (Ce(IV) and Gd(III)), cross-linker (ethylene glycol dimethacrylate), initiator (AIBN), and multiwalled carbon nanotubes. The modified sensor was used for the simultaneous analysis of both template ions in aqueous, blood serum, and waste-water samples, using differential pulse anodic stripping voltammetry which revealed two oxidation peaks for respective templates with resolution as much as 950 mV, without any cross reactivity, interferences and false-positives. The detection limits realized by the proposed sensor, under optimized conditions, were found to be as low as 0.07 ng mL⁻¹ for Ce(IV) and 0.19 ng mL⁻¹ for Gd(III) (S/N = 3) that could eventually be helpful for lanthanide estimation at stringent levels.     

Application of HPLC to measure vanadium in environmental,biological and clinical matrices

Vanadate and vanadium compounds exist in many environmental, biological and clinical matrices, and despite the need only limited progress has been made on the analysis of vanadium compounds. The vanadium coordination chemistry of different oxidation states is known, and the result of the characterization and speciation analysis depends on the subsequent chemistry and the methods of analysis. Many studies have used a range of methods for the characterization and determination of metal ions in a variety of materials. One successful technique is high performance liquid chromatography (HPLC) that has been used mainly for measuring total vanadium level and metal speciation. Some cases have been reported where complexes of different oxidation states of vanadium have been separated by HPLC. Specifically reversed phase (RP) HPLC has frequently been used for the measurement of vanadium. Other HPLC methods such as normal phase, anion-exchange, cation-exchange, size exclusion and other RP-HPLC modes such as, ion-pair and micellar have been used to separate selected vanadium compounds. We will present a review that summarizes and critically analyzes the reported methods for analysis of vanadium salts and vanadium compounds in different sample matrices. We will compare various HPLC methods and modes including sample preparation, chelating reagents, mobile phase and detection methods. The comparison will allow us to identify the best analytical HPLC method and mode for measuring vanadium levels and what information such methods provide with regard to speciation and quantitation of the vanadium compounds.     

水合醋酸铈直接热分解制备超细氧化铈及其抛光性能

Ultra fine ceria was prepared by calcining hydrate cerium acetate. The effects of pyrolysis temperature on the particle size, morphology, specific surface area and loose packing density of ceria were investigated, and the removal rate of optical glasses polishing by ceria was determined. The results show that with the increase of pyrolysis temperature, the loose deposit density and crystallinity increases and the specific surface area decreases, however, the particle size decreases firstly and then increases, the minimum medium particle size D₅₀ is 0.47 μm at pyrolysis temperature of 1 000 ℃. The SEM images of ceria prepared by the decomposition at 800 ℃ or at 1 100 ℃ show porous powders or quasi-sphere small particles with loosely agglomeration, respectively. It was found that the removal rate varied with pyrolysis temperature in preparation of ceria and the property of glass polished. The removal rate for three kinds of glasses was in the order of ZF7> F1> K9, and the maximum value appeared at around 1 000 ℃ for ZF7 and F1, and at around 1 100 ℃ for K9.     

大气压电离质谱在超高纯气体纯度分析中的应用

超高纯气体在工业领域有着重大的需求,必须有相应的高灵敏度杂质检测技术作为支撑。大气压电离质谱(APIMS)具有非常高的灵敏度,通常比电子轰击质谱(EIMS)高104~106倍,是分析超高纯气体纯度最有效的方法。该文介绍了APIMS的产生、发展及电离原理,并综述了以往APIMS对超高纯气体纯度分析的工作,包括底气、杂质种类、杂质检出限及特殊杂质的检测方法。由于方法灵敏度对超高纯气体纯度分析至关重要,文中侧重总结了文献中报道的不同杂质的检出限。