沈阳地区正常人尿液中微量元素的测定

用电感耦合等离子体发射光谱法对沈阳地区正常人尿液中的铬、铁、锰、铝、镉、铜、锌、镍进行了测定,并考察了健康人不同年龄段各元素含量是否存在显著性差异。结果表明,各元素线性关系良好,回归系数为0.9990~0.9998,检出限为0.0004~0.0295μg/mL,方法精密度为1.9%~6.3%,回收率均为80%~120%。健康人不同年龄段尿液中Cd含量有显著性差异(P<0.01)。     

口腔癌患者尿液萘酚反应物的高效液相色谱荧光检测法筛查

利用高效液相色谱荧光检测法(HPLC/FLD)对口腔癌患者尿液中的萘酚反应物(NNR)进行分离分析,通过对34例口腔癌患者和18例健康人尿液的NNR进行分析,比较了癌症患者及健康人尿液中的成分含量差异,提出了一种可用于口腔癌辅助诊断的新方法。结果表明,在健康人及口腔癌患者尿液的萘酚反应物(NNR)中可检出一种标记物,其激发波长为440 nm,发射波长为539 nm。该标记物含量在口腔癌患者中较低,而在健康人群中显著偏高,这与通常的鉴定结果不同。通过采用非参数检验(Mann-Whitney U检验),该标记物含量在健康人群与口腔癌症患者中存在显著性差异(P0.01),其特异度为94.1%,敏感度为94.4%,ROC曲线下面积(AUC)为0.989。该模型具有较高的诊断价值,能够用于口腔癌的辅助鉴定。     

深圳市龙岗区儿童头发和全血中锌、铅含量的测定和比较分析

用电感耦合高频等离子体发射光谱仪测定了龙岗区布吉镇223例3～4岁健康儿童全血和头发的锌、铅含量，给出了各元素在全血和头发中的平均含量值和变动范围。结果表明，头发中的微量元素含量一般较全血中为高，且变动较小。对儿童全血微量元素含量随年龄、体重、性别变化及全血和头发中锌、铅含量的相关关系进行了统计学检验。通过对测定值的比较分析，认为无论是头发或是全血，男性或女性，铅和锌均呈负相关，且大多有显著性；男性和女性的发铅和血铅均呈显著正相关，而女性发锌与血锌也呈显著正相关。     

自动电位滴定法测定工业碳酸钠中氯化钠含量

采用自动电位滴定法,用硝酸银标准溶液作为滴定剂,测定工业碳酸钠中氯化钠含量。方法检出限为0.13mg/L,不同含量氯化钠样品加标回收率为99.7%~100.3%,相对标准偏差(n=5)为0.17%~2.0%,方法简单、快速,精密度和准确度高,适合大批量快速分析样品。     

电感耦合等离子体原子发射光谱法(ICP-AES)测定贵金属车间外排水中的铜、硒、碲

建立了电感耦合等离子体原子发射光谱法测定贵金属外排水中铜、硒、碲3种元素含量的分析方法。选择仪器的最佳工作条件为射频功率1 150 W,雾化器流速0.5L/min,观测高度12mm。确定了各元素测定谱线铜327.396nm、硒196.090nm、碲214.281nm作为各元素的分析线,方法的回收率在98%~103%,测定结果相对标准偏差(n=7)在0.97%~3.1%,检出限铜为0.001μg/mL、硒为0.010μg/mL、碲为0.007μg/mL,方法快速,简捷,有良好的精密度和准确度,能够满足日常生产检测需要。     

二维超高效液相色谱-三重四极杆/复合线性离子阱质谱联用快速测定全血和尿液中鱼藤酮

建立了采用二维超高效液相色谱-三重四极杆/复合线性离子阱质谱联用快速测定全血和尿液中鱼藤酮的检测方法。尿液经水等量稀释后直接进样分析;全血用乙腈沉淀除蛋白质,上清液用水稀释后进样分析。样品中的鱼藤酮被Cyclone柱保留并去除大分子杂质,然后再被流动相洗入第1维Kinetex Biphenyl色谱柱(联苯基核壳柱)进行分离,再将含有鱼藤酮的流分切割至第2维Acquity BEH C_8色谱柱上进行分离,采用多离子监测触发的增强子离子(MRM-IDA-EPI)扫描方式检测,溶剂标准外标法定量。全血和尿液中的平均加标回收率分别为84.6%~94.3%和88.4%~95.7%,相对标准偏差为2.6%~7.3%和2.8%~6.8%(n=6),方法的检出限为0.2和0.03μg/L。该方法已成功应用于鱼藤酮中毒样品的检测。     

湿法消解-原子荧光法测定全血中硒

以全血样品为原料,探讨湿法消解-原子荧光法测定全血中的硒含量。血样经硝酸-高氯酸消解后,用硼氢化钠将硒还原成硒化氢,由氩气载入原子化器,产生的原子荧光强度与试液中硒元素含量在一定范围内呈正比,外标法定量。以消解效率为指标,优化样品的消解条件,测定血中硒在0-10μg/L范围内线性情况良好,相关系数为0.9992,最低检出限为0.143μg/L,相对标准偏差为1.51%-1.58%,平均加标回收率为90.86%-104.62%。血中硒的原子荧光测定法灵敏度高,精密度和稳定性好,可应用于血中硒的生物监测。     

在线固相萃取结合液相色谱-线性离子阱多级质谱法同时检测生物样品中7种乌头类生物碱

建立了在线固相萃取(on-line SPE)结合液相色谱-线性离子阱多级质谱(LC-LIT/MSⁿ)同时测定全血、尿液和肝组织样品中7种乌头类生物碱的分析方法,并根据7种乌头类生物碱的多级质谱碎片对裂解规律进行了推测和总结。用乙腈沉淀样品中的蛋白质,于稀释和离心后直接进样。经Waters Oasis^® HLB在线SPE柱富集纯化,以0.1%(v/v)甲酸/乙酸铵溶液-0.1%(v/v)甲酸/甲醇溶液为流动相,以Accucore C18为分析柱进行梯度洗脱;在电喷雾电离(ESI)正离子模式下测定;扫描方式为连续反应监测(CRM)。在考察的质量浓度范围内,7种乌头类生物碱的标准曲线符合二阶方程(权重因子1/x),相关系数为0.9991~0.9999;在全血和尿液中的方法检出限为0.02~0.60 ng/mL,在肝组织中的方法检出限为0.02~0.40 ng/g;加标回收率为91.1%~104.7%,日内精密度和日间精密度分别为0.2%~10.7%、1.0%~13.7%(n=6)。该方法简单准确,灵敏度高,能够满足生物样品中7种乌头类生物碱的快速分析。     

原子荧光法测定茶叶中的硒含量

采用原子荧光法测定茶叶中的硒含量,对样品消解温度及仪器条件进行了优化。还原剂为1.0%硼氢化钾–0.5%氢氧化钾溶液,载流液为3%盐酸溶液。在优化条件下,硒的质量浓度在0~20 ng/mL范围内与荧光强度呈良好的线性关系,相关系数r=0.999,检出限为0.8 ng/mL。该法的加标回收率为88.08%~101.39%,测定结果的相对标准偏差为2.03%~4.84%(n=6)。该方法实际操作性强,准确度高,适用于日常检验工作中对批量茶叶中硒含量的测定。     

急性气管—支气管炎患者头发及血清微量元素的测定及其临床意义

用原子吸收光谱法测定了86例急性气管-支气管炎患者及66例健康人头发及血清锌、铁、铜、锰4种微量元素的含量。结果显示,锌、铁元素的含量比对照组低,并表现有显著性差异(P<0.01),铜、锰元素的含量在两组之间无显著性差异(P>0.05)。     

Development of extraction methods for speciation analysis of selenium in aqueous extracts of medicinal plants

Advanced extraction methods have been developed for direct speciation of dissolved inorganic and organic selenium (Se) species in aqueous extracts of medicinal plants (MPs). The inorganic species of Se (SeIV and SeVI) were separated from organic forms by adsorbing inorganic Se on alumina, while the organic Se was not retained. The retained inorganic Se species was eluted with 10 mL 0.2 M HCl. The total inorganic Se species was determined after prereduction of SeVI into SeIV with concentrated HCl. The SeIV in the eluent and total inorganic Se species were then complexed with diethyldithiocarbamate. The resultant complexes were entrapped in the nonionic surfactant Triton X-114. The total Se, organic Se, total inorganic Se, and SeIV species were determined by electrothermal atomic absorption spectrometry with a modifier. The SeVI concentration was obtained by subtracting SeIV from total inorganic Se contents. The main factors affecting the methodologies were investigated in detail. Under the optimized experimental conditions, the LOD for SeIV was 50 microg/L. Among dissolved inorganic and organic Se species in aqueous extracts of MPs, organic Se species were present in the range of 74-84%, SeIV 3.62-7.47%, and SeVI 12.4-18.57% of total Se contents.     

富硒香菇规模化栽培实验及其富硒规律研究

为了了解规模化栽培后富硒香菇的产量（生物学效率）及富硒规律，本实验通过香菇栽培基质添加模式，采取规模化生产进行富硒香菇栽培试验，选取不同浓度硒营养强化剂对香菇品种“向阳二号”和“9608”进行添加，测定相对应的香菇生物学效率以及第一潮次和第二潮次的总硒及硒代氨基酸的含量。实验发现向阳二号香菇，在硒添加量较低（0-6mg/kg）时香菇的生物转化率基本不随硒添加量的增加而改变，当硒添加量继续增加（10-60mg/kg）时，香菇的生物转化率整体低于低添加量；9608香菇，随着硒添加量的增加（0～60mg/kg），香菇的生物转化率表现出微弱的增加趋势，但差异性不显著；而两种不同品种、潮次香菇的总硒及硒代氨基酸含量均随着硒添加量的增加而提高，但硒代氨基酸占总硒的比例变化趋势却有所不同，在66.7-85.4%范围内。此外，对于不同品种的香菇，其第一潮次总硒含量在硒的添加量在0～20 mg/kg的范围内呈现良好的规律性，总硒是基质（风干）中硒含量的约4-5倍。可见，按照该规模化栽培模式进行生产栽培，可以得到总硒含量稳定、硒代氨基酸占总硒比＞65%的富硒香菇产品，对富硒香菇产业的发展有一定的指导意义。     

催化碘酸钾氧化异硫氰酸荧光素荧光猝灭法测定痕量硒

基于异硫氰酸荧光素(FITC)可发射强而稳定的荧光信号,KIO3能氧化FITC而发生荧光猝灭,Se(Ⅳ)使FITC的荧光强烈猝灭,Se(Ⅳ)的含量与ΔF值呈线性关系,建立催化KIO3氧化FITC荧光猝灭法测定痕量硒的新方法.方法的线性范围为0.012～2.000×10-15g Se(Ⅳ)/mL,工作曲线回归方程ΔF=1.18+72.74CSe(Ⅳ)(×10-15g/mL)(n=6,r=0.9997),检出限为2.1×10-18g/mL(n=11).分别对Se(Ⅳ)浓度0.012和2.000×10-15g/mL进行7次测定,RSD依次为2.8%和3.5%.用于实际样品中痕量硒的测定和人体疾病的诊断与预报,结果满意.同时探讨了催化荧光猝灭法测定痕量硒的反应机理.     

高碘酸钾氧化中性红褪色催化动力学光度法测定痕量硒(Ⅳ)

基于3.2×10-4mol/LH2SO4介质中,痕量硒(Ⅳ)催化KIO4氧化中性红的褪色反应,建立了测定痕量硒(Ⅳ)的动力学光度法。在固定加热时间段(6min)后,于530nm处测定中性红的吸光度降低值监控反应速率。方法检出限为0.36μg/L,校准曲线的质量浓度线性范围为0～8.0μg/L。实验了酸度、反应物浓度、温度、反应时间、干扰离子等因素的影响。研究了反应的最佳条件,并测定了一些动力学参数,催化反应的表观活化能为81.60kJ/mol。11次重复测定0.1μg/25mL和0.2μg/25mLSe(Ⅳ)的相对标准偏差分别为2.1%和1.9%。方法用于食品和人发样品中痕量硒(Ⅳ)的测定,相对标准偏差为0.33%～3.8%,加标回收率为96.0%～103.0%。     

Isotopic determination of selenium in biological materials with inductively coupled plasma mass spectrometry

A method for the isotopic determination of selenium in biological matrices is described. The method is based on hydride generation inductively coupled plasma mass spectrometry (ICP-MS). The development is specifically related to the requirements of stable isotope tracer studies in human subjects. The method is based on isotope dilution using 82Se as the in vitro spike and can quantify the 74Se and 77Se contents of samples. It involves wet oxidation (HNO3 - H2O2 or HNO3 - HClO4) of the 82Se-spiked matrix, reduction to selenite by boiling with HCl followed by measurement of the isotope ratios (82Se/77Se and 74Se/77Se) in the gas stream (H2Se) generated from on-line reduction of the sample selenite with NaBH4. Compared with the isotopic signal resulting from a selenite solution containing 5 ng ml-1 of Se, the total sample blank contributions at m/z = 74, 77 and 82 were less than 5% of the respective isotope signal. Worst-case absolute detection limits were 0.2-0.9 ng of Se, depending on the isotope used. Ion beam intensity ratios were measured with an over-all precision [relative standard deviation (RSD)] of 1% for both isotope pairs. Measured ratios (MRa/b) were stable during a given day's operation within the expected precision of the measurements but varied for different days. The magnitude of MRa/b was generally independent of the nature of the matrix. Highly linear relationships were found between ion beam intensity ratios (MRa/b) and the corresponding true isotope ratios for calibration solutions whose isotope ratios had been altered by as much as one order of magnitude.(ABSTRACT TRUNCATED AT 250 WORDS)     

Sequential speciation of selenium by flow injection cathodic stripping voltammetry

A semi-automatic continuous method for the determination of Se(IV) based on flow-injection cathodic stripping voltammetry (FICSV) is reported. The flow injection approach incorporates a thin mercury film on glassy carbon as the working electrode, on which Se(IV) is deposited at an applied potential of 0.0 V. A cathodic scan (from 0.0 to –0.9 V) is applied and the Se is stripped at –0.54 V, providing a current intensity proportional to the Se(IV) concentration in the sample. This method features a linear determination range between 0.5 and 30 ng/ml (r²=0.998, RSD=3.6%). The non-interference levels (foreign species to analyte ratio) are 2.5:1 for Cu(II), 7.5:1 for Pb(II), 35:1 for Cd(II), 250:1 for Zn(II) and 500:1 for Fe(III). After developing the method for Se(IV), the speciation of this element has been performed by sequential injection of the dissolved sample into a carrier which may or may not have been previously reduced off-line thus determining the sum (Se(IV)+Se(VI)) or only Se(IV), respectively. The method has been applied to selenium speciation in water samples.     

Application of NAA to the Determination of Mineral and Trace Elements in Brazilian Diets at IPEN/CNEN/SP

In the present work, the concentration of the 14 elements Br, Ca, Cl, Co, Cs, Fe, K, Mn, Na, Rb, Sc Se and Zn have been determined by INAA in diets of four different groups: (a) 19 pre-school children, (b) 18 healthy adults, (c) 23 elderly people living in private institutions and (d) 19 patients with chronic renal failure (CRF). The contents of proteins, lipids and carbohydrates were also analysed in the diets. The daily intakes of the elements analysed were compared to the recommended values set by RDA or WHO.     

探讨维甲酸诱导小鼠肝癌细胞凋亡血清微量元素的变化

为探讨维甲酸诱导小鼠肝癌细胞凋亡的血清微量元素的变化,收集30例实验组BALBC小鼠血清标品,应用等离子体发射光谱仪测定了se、zn、cu、Fe、Ca、Mg含量。结果表明,血清微量元素含量测定,维甲酸组Zn、Mg含量低于对照组,se、cu、Fe、ca含量和对照组比差异无显著性（P〉0．05）。提示维甲酸诱导小鼠肝细胞凋亡,血清微量元素含量变化不大与肝癌发生、靠展无相关件．     

β-环糊精对燃煤焦油和烟气中环芳烃的清除作用

采用三维荧光法测定了7处产地煤样燃烧的焦油和烟气中多环芳烃（PAHs）的含量,焦油中PAHs含量为0.201～0.419 mg/g,烟气中PAHs含量为1.1～3.2 μg/g;测试了β-环糊精（β-CD）溶液对煤烟气中多环芳烃的清除作用,最高去除率可达65.6%。 结果表明：不同产地煤的烟气中PAHs含量不同, 煤焦油中PAHs浓度(mol/L)在10-5数量级,远高于烟气中的浓度(mol/L,10-7数量级)。 用β-CD去除不同产地煤燃烧烟气中多环芳烃的去除率不同。 所选7种煤平均清除率为38.4%。 β-CD溶液有希望成为煤烟气中多环芳烃的清除剂。     

Selenium supplementation of Portuguese wheat cultivars through foliar treatment in actual field conditions

Selenium (Se) is a trace element essential to the well-being and health quality of humankind. Plant-derived foodstuffs, namely cereals, are the major dietary sources of Se in most countries throughout the world, even if Se contents are strongly dependent upon the corresponding levels in cereal-growing soils. Therefore, wheat is one of the staple crops that appears as an obvious candidate for Se biofortification, considering its gross-tonnage production and nutritional relevance worldwide. The present paper focuses on the ability of bread and durum wheat—Triticum aestivum L. and Triticum durum Desf., respectively—to accumulate Se after supplementation via a foliar-addition procedure. Two of the most representative wheat cultivars in Portugal—Jordão (bread) and Marialva (durum)—have been selected for supplementation trials, following the same agronomic practices and field schedules as the regular (non-supplemented) crops of those varieties (sowing: November 2010; harvesting: July 2011). Foliar additions were performed at the booting and grain-filling stages, using sodium selenate and sodium selenite solutions at three different Se concentrations—equivalent to field supplementation rates of 4, 20 and 100 g of Se per ha—with and without potassium iodide. Selenium contents in wheat grains obtained under foliar application are compared to data from regular wheat samples (field blanks) grown at the same soil/season, yet devoid of any Se supplementation. Total Se in all field samples was determined by cyclic neutron activation analysis (CNAA), via the short-lived nuclide ^77mSe (half-life time: 17.5 s), in the Portuguese Research Reactor (RPI; CTN-IST, Sacavém). Quality control of the analytical procedure was asserted through concurrent analyses of NIST-SRM^® 1567a (Wheat Flour). Results show that foliar additions can increase Se contents in mature grains up to 15 and 40 times for Marialva and Jordão, respectively, when compared to non-supplemented crops. Jordão and Marialva varieties responded differently to the stage of application.