Determination of non-toxic and potentially toxic elements concentration and antioxidant capacity in selected natural and essential oils with high market values

Natural oils (NOs) and essential oils (EOs) are widely used in the food and beverage, medical, aromatherapy and cosmetic industries, but little is known about their elemental composition or antioxidant ability. Microwave-assisted acid digestion and inductively coupled plasma-optical emission spectroscopy were used to determine the non-toxic elements (Al, Ca, Cu, Fe, K, Mg, Na, Se and Zn) and potentially toxic elements (As, Cr, Cd, Mn, Ni and Pb) concentrations in 13 selected NOs and EOs. The per cent recoveries of laboratory-fortified blanks analysed for quality control were 94–110%. The elemental concentrations varied widely in NO and EO samples, as demonstrated by the large standard deviation obtained for some elements. The average levels of non-toxic elements (Al (14.5 ± 3.7 μg/g); Ca (278 ± 138 μg/g); Cu (7 ± 14 μg/g); Fe (16 ± 5 μg/g); K (36 ± 31 μg/g); Mg (56 ± 27 μg/g); Na (266 ± 277 μg/g); Se (0.7 ± 0.3 μg/g) and Zn (6.1 ± 2.6 μg/g)) were determined in NOs and EOs. Comparatively, low levels of potentially toxic elements (As (0.1 ± 0.2 μg/g); Cd (0.1 ± 0.0 μg/g); Cr (0.2 ± 0.1 μg/g); Mn (0.8 ± 0.1 μg/g); Ni (4.5 ± 2.2 μg/g); and Pb (0.3 ± 0.2 μg/g)) were obtained in the oils. Principal component analysis (PCA) revealed that the first two principal components explained 100% of the variability in the elemental concentrations. Na, Ca, Mg and K were the main contributors to PCA. Non-toxic element pairs were strongly correlated (R² > 0.9440) indicating a common source in these oils, but toxic element pairs were poorly correlated. Although toxic element concentrations were low, routine monitoring in oils is recommended. The antioxidant ability of NOs and EOs to potentially reduce free radicals, which are often involved in several degenerative diseases, such as ageing, stroke, diabetes and cancers was determined by DPPH (2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl) free radical scavenging assay and ultraviolet-visible spectroscopy. Jasmine, castor and tea tree lemon oils were the best antioxidants. The oils in this study have the potential to replace artificial antioxidants used in foods, cosmetics and other products.     

磁性碳包铁纳米粒子在重金属元素检测分离富集中的应用

以氩电弧等离子体法制备的碳包铁纳米粒子为固相萃取材料,采用等离子体原子发射光谱法(ICP-AES)系统研究了该材料对Cr、Ni、Cd、Pb离子的吸附性能,并确定了最佳吸附和洗脱条件。实验结果表明:当pH值为8.0～9.0时,分析物均可被碳包铁纳米粒子定量吸附;采用酸性溶液(pH=1.0～2.0)可将吸附在碳包铁纳米粒子上的金属离子完全脱附。该法对Cr、Ni、Cd、Pb的检出限分别为3.6、4.1、1.1、9.8μg/L,Cr、Ni、Cd的线性范围为1～500μg.L-1,Pb的线性范围为10～1 000μg.L-1,线性相关系数均大于0.999。方法用于自来水中Cr、Ni、Cd、Pb离子的测定,回收率可达到93%～105%;碳包铁纳米粒子对Cr、Ni、Cd、Pb离子的吸附量分别为3.6、4.8、6.3、2.1 mg/g。     

嵌段分子筛聚合材料P123-SH萃取分离-石墨炉原子吸收光谱法分析痕量铬的形态

研究了嵌段分子筛聚合材料P123-SH萃取分离-石墨炉原子吸收光谱法对尿中痕量铬的形态分析方法,探讨了嵌段分子筛聚合材料P123-SH吸附铬的原理和最佳条件。在pH 7.0、常温下,Cr3+和Cr(Ⅵ)被很好的分离,且Cr3+可被该材料定量吸附,其吸附容量为6.15 mg/g。吸附的Cr3+可用2 mol/L的HCl洗脱,用石墨炉原子吸收法测定洗脱下来的Cr3+,往溶液中加入0.1%抗坏血酸将Cr(Ⅵ)还原为Cr3+测总铬,Cr(Ⅵ)含量为总铬减去Cr3+,方法测定Cr3+的检出限为0.011μg/L(3σ,n=11),线性范围为0.1～10μg/L,加标回收率在94%～106%之间,对0.50μg/L的Cr3+溶液平行测定7次,RSD为3.6%。方法可应用于生物样品和环境样品中痕量铬的形态分析。     

Analysis of abuse drugs in urine using surfactant-assisted dispersive liquid-liquid microextraction

The process of surfactant-assisted dispersive liquid-liquid microextraction (SA-DLLME) followed by high-performance liquid chromatography-UV detection was successfully applied for the extraction and determination of selected cannabinoids (cannabidiol, Δ(9)-tetrahydrocannabinol, and cannabinol) in urine samples. The effective parameters on the extraction efficiency were studied and optimized utilizing two different optimization methods: one variable at a time (OVAT) and face center design (FCD). Under the optimum conditions (extraction solvent and its volume, toluene, 85 μL; disperser agent and its concentration, 1.0 mL of ultra-pure water containing 0.5 mmol/L tetradecyl tremethyl ammonium bromide (TTAB); sample pH, 2.0 and salt concentration, 11% w/v NaCl), the limits of detection of the method were in the range of 0.1-0.5 μg/L and the repeatability and reproducibility of the proposed method, expressed as relative deviation, varied between 4.1 and 8.5% and 6.7 and 11.6%, respectively. Linearity was found to be in the range of 1.0-200 μg/L and under the optimum conditions, the preconcentration factors (PFs) were between 190 and 292. This proposed method was successfully applied in the analysis of three male advocate urine samples and good recoveries were obtained.     

混凝土中重金属元素溶出量的质谱分析

利用带八极杆碰撞/反应池和屏蔽炬技术的电感耦合等离子体质谱直接测定混凝土中Cr,Mn,Ni,Cu,Zn,As,Cd,Sn,Sb,Pb等多种重金属元素的溶出量。通过向碰撞池中引入氢气和氦气消除多元素分子离子的干扰,以50μg/L的Ge,In,Tb为内标元素校正基体干扰和漂移。10种待测元素的检出限为0.001～0.033μg/L,相对标准偏差为0.85%～2.8%,样品的加标回收率在91.1%～103.9%之间。     

Square wave Stripping voltammetry of Cobalt Based on Adsorptive accumulation of its Hydroxynaphthol Blue (HNB) Complex at the Static Mercury Drop Electrode

ABSTRACT

A new method is described for the determination of cobalt based on the square wave adsorptive stripping voltammetry of Co(II) complexed with hydroxynaphthol blue (HNB) at the static mercury drop electrode. Optimal conditions were found to be: preconcentration potential, -0.500V vs. Ag/AgCl (KCl 3M); preconcentration time, 30 s (with stirring); pulse height, 50 mV; frequency, 100 Hz; scan increment, 4 mV; step time, 0.010 s; supporting electrolyte, HEPES/HCl (0.1 M, pH 7.0-8.0) or triethanolamine/HCl (0.1 M, pH 7.6); concentration of hydroxynaphthol blue, 5.0 × 10^?6 M. The response of the system was found to be linear in a range of Co(II) concentrations from 2.0 to 10.0 μg/L. The limit of detection was found to be 1.8 × 10^?9 M with 2 minutes of preconcentration time. The effect of various potential interferences were also studied including a variety of cations, anions and organic surfactants. The interferences by Ni(II), and Cr(VI) may be eliminated by addition of EDTA or CDTA and the of Fe(III) and Ti(IV) by fluoride. The merits of the procedure were demonstrated in the analysis of certified and biological samples.     

直接稀释进样-电感耦合等离子体原子发射光谱法同时测定原油中20种元素

原油样品(2.0g)用稀释剂航空煤油稀释至20.0g后,直接进样供电感耦合等离子体原子发射光谱法测定其中银、铝、硼、钡、钙、镉、铬、铜、铁、镁、锰、钼、钠、镍、铅、硅、锡、钛、钒和锌等20种元素的含量。在优化的试验条件下,20种元素的检出限(3S/N)在0.1～3mg·kg-1之间。方法用于分析原油样品,所得测定值的相对标准偏差(n=6)在1.24%～6.23%之间,回收率在80%～105%之间。     

环形聚焦单模微波消解–ICP–MS法检测罐头食品中钒、铬、镍、镉、铅、砷、锰、铝、铜、锡

建立环形聚焦单模微波消解–电感耦合等离子体质谱法同时测定罐头食品中钒、铬、镍、镉、铅、砷、锰、铝、铜、锡金属元素的含量。采用浓硝酸消解样品,各元素分析目标物分别为Pb208,Cd111,As75,Mn55,Cu63,V51,Ni60,Sn120,Cr53,Al27。Pb208以Bi209为内标,Cd111,Sn120以In115为内标,Ni60,Cr53,V51,Mn55,Cu63,As75,Al27以Sc45为内标。各元素工作曲线线性良好,相关系数不小于0.999 5,方法检出限为0.0030~0.030μg/g,加标回收率在98.0%~104.1%之间,测定结果的相对标准偏差为1.29%~4.50%(n=6)。该方法简便快捷,灵敏度高,适合分析大批量罐头食品中多种金属元素。     

Slurry atomization of wheat-milled fractions for electrothermal atomic absorption spectrometric determination of nickel and chromium.

A slurry electrothermal atomic absorption spectrometric technique was used to determine Ni and Cr in wheat flour and its by-products. Slurries (3%, w/v) were prepared in a mixture of 15% HNO3-10% H2O2 as suspended medium. Differences in Ni and Cr contents due to origin and texture of the wheat and to the effects of the milling process were studied. Ni and Cr levels were more markedly influenced by the geographical origin of the wheat than by its texture. Both metals were related to the amount of bran present in each milled fraction and varied over the ranges of 212-298 ng/g (Ni) and 34-85 ng/g (Cr) in flours (with minimal bran contents); 297-460 ng/g (Ni) and 67-118 ng/g (Cr) in shorts; and 424-723 ng/g (Ni) and 106-165 ng/g (Cr) in brans. The Ni and Cr contents were not significantly affected by the technological processes typically performed in a flour-producing factory.     

高效液相色谱-四极杆/线性离子阱质谱测定替米沙坦中N-甲基邻苯二胺残留量

建立了高效液相色谱-四极杆/线性离子阱质谱(HPLC-QTRAP-MS/MS)测定替米沙坦中N-甲基邻苯二胺残留量的分析方法。替米沙坦药物以水-乙腈(80∶20,体积比)溶解后,采用Agilent Eclipse XDB-C18色谱柱(3.5μm,2.1 mm×100 mm)进行分离,以0.1%(体积分数)甲酸水和乙腈作为流动相进行梯度洗脱,电喷雾正离子(ESI+)扫描方式下选择离子监测(SRM)模式对样品进行检测。结果表明,N-甲基邻苯二胺在2.0~50μg/L范围内线性关系良好(r0.99),检出限(S/N=3)为0.5μg/L,定量下限(S/N=10)为2.0μg/L。该方法操作简单、灵敏度高、重现性好,可用于替米沙坦中N-甲基邻苯二胺残留量的测定。     

Multielemental analysis in small amounts of environmental reference materials with inductively coupled plasma mass spectrometry

The lowest possible sample weight for performing multielemental trace element analysis on environmental and biological samples by ICP-MS has been investigated. The certified reference materials Bovine Liver NIST SRM 1577b, Human Hair NCS DC 73347 and Oriental Tobacco Leaves CTA-OTL-1 were applied at sample weights (1, 5, 20 and 50 mg aliquots, n = 10) which were significantly lower than those recommended with most recoveries in the range of 95–110%. Samples were digested in a mixture of nitric acid, hydrogen peroxide and hydrogen fluoride by closed-vessel microwave digestion. Multielemental analysis was performed with an optimized ICP-QMS method. Aqueous standard solutions were applied for external calibration with rhodium as the internal standard element. The detection limits varied between 0.02–¶0.38 μg/g for Li, Na, Cr, Mn, Ni, Cu, Zn, Sr, Cd, Ba and Pb, and up to 1.92 μg/g for Mg, Al, Ca, Fe and Ni. Digested human plasma samples were spiked with multielemental solution (0.5–10 μg/L) to test the analytical method and the recoveries were 95–105% for most analytes. Our results show that in the case of homogeneous SRMs it is possible to use them in very low amounts (1–5 mg) for method development and quality control.     

Extractive separation of Tungsten as phosphotungstate

Tungsten can be extracted quantitatively as phosphotungstate in micro as well as milligram concentrations by extraction with MIBK from 0.1-1M hydrochloric acid if the w/w tungsten:phosphorus ratio = 7, and separated from Fe, Ni, Co, Cr, Mn, Cu, Ca, U, Th, As, Sb, Bi and Si, after reduction of Fe(III) and cr(VI) with thiosulphate, in natural and industrial samples. Mo and V suppress the extraction of tungsten and therefore require prior separation. The method takes 15 min for a single separation and gives highly satisfactory results with an overall error of about 0.1-0.2% over the range 10-100 mg tungsten in the sample.     

Synthesis and Efficiency of a Spherical Macroporous Epoxy-dicyandiamide Chelate Resin for Preconcentrating and Separating Trace Au, Hg, Pd and Ru from Samples

IntroductionThe preconcentration and separation of elements in samples by means of a chelateresin[l--5J or a chelate fibre[6'7J have been reported. However, the synthesis of the resin or thefibre usually takes a long time and a complex synthetic process. Accordingly, the epoxy--tan-ning chelate resin[8] and the epoxy-urea chelate .esin[9] have been synthesized and used for thepreconcentration of trace elements. However, these chelate resins could not be used for theenrichment of trace element…     

熔体旋淬合金Zr_(0.9)Ti_(0.1)(Ni,Co,Mn,V)_(2.1)的微结构与电化学性能

对比研究了熔体旋淬和常规熔铸合金Zr0 .9Ti0 .1(Ni,Co ,Mn ,V) 2 .1的微结构和电化学性能 .XRD分析表明 :熔体旋淬合金在退火前后的晶体结构和铸态合金一样 ,均为面心立方结构 ,由LaveC15相组成 ;并且随旋淬速度的增加 ,旋淬合金中的非晶成分越多 .电化学测试表明 :旋淬合金有较好的活化性能 ,但其最大放电容量较低 ,小于 2 80mAh/g ;而退火后的旋淬合金需经 30次循环才能完全活化 ,其最大放电容量皆为 34 0mAh/g左右 ,高于铸态合金和退火前的旋淬合金 ;在电流密度为 30 0mA/g下进行充放电循环 ,发现退火后的旋淬合金循环稳定性明显高于铸态合金电极 ,并且随旋淬速度的增加 ,循环稳定性越好 ,经过 80 0次循环后 ,退火后的 4 0m/s合金容量保持率高达 85 % ,容量衰减率只有 6.9%     

On Atomization of Calcium,Magnesium and Antimony from ThO2 Matrix by Atomic Absorption Spectrometric Techniques

ABSTRACT

Atomic Absorption Spectrometric methods (AAS) developed for the direct determination of Ca and Mg using flame-AAS technique have linear ranges of 0.1-2.0 μg/ml and 0.025-0.4 μg/ml with thorium concentrations optimized at 2.5 and 0.5 mg/ml, respectively, while the analytical range obtained for Sb using electrothermal-AAS technique is 0.002-0.1 μg/ml with Th sample aliquot of 2.5 mg/ml. The precision of determinations for both the techniques as evaluated from analyses of synthetic samples is 5% RSD or better. Probable mechanism for atom formation for Sb has been discussed in detail. In addition, role of chemical modifiers in enhancing the analyte signal has also been discussed.     

AAS determination of Co, Ni, Mn and Cr in ores, concentrates and dusts from copper metallurgy after matrix elements separation by extraction

Summary A method has been developed for the AAS determination of Co, Ni, Mn and Cr in ores, concentrates and dusts of copper metallurgy at the 10^–3–10^–1% level. The matrix elements (Cu, Pb, Zn, Fe) were separated in a two-stage extraction: with MIBK from 6 M HCl solution and with 0.1 M tetrahexylammonium iodide (THAI) in MIBK from 3 M HCl, in form of ion-pairs, without Co, Ni, Mn and Cr losses. Values of r.s.d. were 2.0–6.0%.

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AAS-Bestimmung von Co, Ni, Mn und Cr in Erzen, Konzentraten und Stäuben aus dem Bereich der Kupfermetallurgie nach Abtrennung der Matrixelemente durch Extraction

Zusammenfassung Das beschriebene Verfahren eignet sich für den Bereich von 10^–3 bis 10^–1%. Die Matrixelemente (Cu, Pb, Zn, Fe) wurden als Ionenpaare ohne Verluste an Co, Ni, Mn und Cr mit Hilfe einer zweistufigen Extraktion abgetrennt: mit MIBK aus 6 M HCl-Lösung und mit 0,1 M Tetrahexylammoniumiodid (THAI) in MIBK aus 3 M HCl-Lösung. Die relativen Stadardabweichungen lagen im Bereich von 2,0 bis 6,0%.

     

Quantification of lurasidone, an atypical antipsychotic drug, in rat plasma with high-performance liquid chromatography with tandem mass spectrometry

A liquid chromatography–tandem mass spectrometric (LC/MS/MS) method was developed for the determination of an atypical antipsychotic drug, lurasidone, in rat plasma. The method involves the addition of acetonitrile and ziprasidone (internal standard) solution to plasma samples, followed by centrifugation. An aliquot of the supernatant was diluted with water and directly injected into the LC/MS/MS system. The separations were performed on a column packed with octadecylsilica (5 μm, 2.0 × 50 mm) with 0.1% formic acid and 0.1% formic acid in acetonitrile as mobile phase and the detection was performed using tandem mass spectrometry by multiple‐reaction monitoring via an electrospray ionization source. The standard curve was linear (r = 0.9982) over the concentration range 0.002–1 μg/mL. The intra‐ and inter‐assay precisions were 1.7 and 8.6%, respectively. The accuracy range was from 90.3 to 101.8%. The lower limit of quantification was 2.0 ng/mL using 50 μL of rat plasma sample. The developed analytical method was successfully applied to the pharmacokinetic study of lurasidone in rats. Copyright © 2011 John Wiley & Sons, Ltd.     

微波消解/ICP-MS同时测定粮食、蔬菜中的11种重金属元素

建立了微波消解/电感耦合等离子体质谱法同时测定粮食和蔬菜中11种重金属元素(Cu、Mn、Cr、Pb、Cd、Ni、Sb、Hg、Co、Ag、As)的方法,优化了微波消解条件和仪器测定条件,采用HNO_3-HF-H_2O_2和HNO_3-H_2O_2两种混酸体系,将样品进行完全消解。结果显示,11种金属元素的线性系数不小于0.999 5,方法的检出限为0.001~10.00μg/L,测定的相对标准偏差(RSD,n=5)不大于5.0%。该方法具有快速、简便、灵敏度高、稳定性好、准确度高等优点。     

微波消解-ICP/MS测定烤烟中微量元素含量

以3 mL HNO3和2 mL H2O2的混合消解液对烟草样品进行微波消解,采用电感耦合等离子体质谱测定了烤烟中的Mn、Zn、Cu、Se、N i、Co、Cr、As、Cd、Pb 10种微量元素的含量.结果表明：方法的检出限均低于0.02μg/g,各元素测定的RSD（n=5）均小于3%,样品加标回收率为97.35%-101.30%.方法消耗试剂少,快速准确,适合烟草中多种微量元素的同时测定.     

Concentrations of major and trace elements in polished rice and paddy soils collected in Aomori,Japan

Rice grain samples and surface paddy soil samples were collected from 20 sites throughout Aomori Prefecture, Japan, and the concentrations of 25 elements in the polished rice and 33 elements in the soils were determined by neutron activation analysis, inductively coupled plasma-mass spectrometer or atomic adsorption spectrometer. The range of essential element concentrations in the polished rice was within one order of magnitude, however, the range for most of the trace elements was more than one order of magnitude. The range of element concentrations, except for I, in the paddy soils was within one order of magnitude. The ±95% confidence intervals of the soil-to-polished rice transfer factors for all elements, except for Pb, were within two orders of magnitude, and the geometric mean values were as follows: Cl, Mo and Zn (0.1–1); K, Cu, Cd, Rb, Mg, Mn, and Ag (0.01–0.1); Ni, As, Ca, Se and I (0.001–0.01); Na, Cs, Sr, Co, Cr, V, Ba, Pb, Fe and Al (<0.001).