食管癌患者肿瘤组织中硒含量的调查测定

应用2，3-二氨基萘荧光测定法对36例食管癌患者癌组织与癌旁组织及血清中硒的含量进行了测定。结果表明，癌组织中硒含量平均为1．325±0．81μg／g干重，癌旁组织为0．893±0．68μg／g干重，两者差异显著（P＜0．05）；血清中硒含量为0.6033±0．0520μmol／L，对照组20例献血员血清为0．8034±0．0650μmol／L，亦有显著性差异（P＜0．05）。提示硒在抗肿瘤的过程中有一定作用。     

悬浮液进样ZAAS测定粉末试样中的Se─—小麦粉、猪肝、甘兰中Se的无标准分析

本文在甘油－硝酸－水介质中，利用悬浮液直接进样进行了小麦粉、猪肝、甘兰中Ｓｅ无标准分析。文中详细地研究了悬浮液介质对测定的影响。找出了甘油：硝酸：水＝１∶０．０５∶４为适宜条件，应用此方法测定了标准物质小麦粉、猪肝和甘兰中Ｓｅ，结果与证书值和荧光法值十分吻合，相对标准偏差（ｎ＝６）最大为７．０％，适合于含Ｓｅ大于０．１μｇ／ｇ的粉末试样中Ｓｅ的测定。     

用石墨炉原子吸收法测定水质中微量砷,硒的探讨

采用石墨炉原子吸收法测定水中微量砷，硒，经大量实验条件摸索，选择不同仪器分析工作条件，找出了最佳升温程序条件，特别是原子化时气流控制，使分析方法的检出限降低为：Ａｓ０．６μｇ／Ｌ，Ｓｅ０．５μｇ／Ｌ。线性范围；Ａｓ０．０００－０．１２０ｍｇ／Ｌ，Ｓｅ０．０００－０．０２４ｍｇ／Ｌ；精密度，相对标准偏差分别为：Ａｓ１．２６％，３．６７％，Ｓｅ２．５６％，４．５７％，回收率为：Ａｓ９８．０％－１１０．     

人体必需微量元素--硒

介绍了硒的生物功能和药理作用,包括：抗氧化作有,促进代谢,增强视力,提高免疫功能,抗癌等。并列举了多种含硒制剂。     

高效液相色谱-原子荧光法测定农作物中无机硒的含量

采用磷酸二氢钾-硫酸铜溶液超声提取,离心过0.45μm滤膜后,高效液相色谱-原子荧光光谱仪测定农作物样品中的Se(Ⅳ)和Se(Ⅵ)含量。本方法的检出限为：Se(Ⅳ)1.5μg/kg,Se(Ⅵ)为1.5μg/kg。本方法的精密度(RSD)为5.8-8.2%和回收率为81.5%-92.5%。     

AE-HG-AFS测定长期汞暴露人群补硒后尿中硒的形态

建立了一种利用阴离子交换高效液相色谱与氢化物发生原子荧光光谱联用同时测定四、六价硒及硒代半胱氨酸(SeCys)形态的方法。优化了六价硒的还原条件及仪器检测参数,以不同浓度的柠檬酸铵作为流动相,在10 min内同时分离了四、六价硒及硒代半胱氨酸(SeCys)。采用加标法定量,加标回收率在90%～119%之间,相对标准偏差为1.6%～3.1%(100μg/L),四、六价硒及硒代半胱氨酸(SeCys)的检出限分别为0.32μg/L、0.47μg/L和0.44μg/L(进样量为100μL)。应用该法对长期汞暴露人群补硒后尿中的小分子硒的形态进行了分析,仅检测到硒代半胱氨酸(SeCys)。     

Determination of Selenium with a Poly(1,8‐diamino‐naphthalene)‐Modified Electrode

The performance of a poly(1,8‐diaminonaphthalene)‐modified electrode for the determination of the Se(IV) ion in an aqueous medium was investigated with anodic stripping voltammetry without the pretreating of the sample. The experimental parameters for the analysis of Se(IV) were optimized and the characteristics of this polymer‐modified electrode were investigated by using cyclic voltammetry. The Se(IV) ions were chemically deposited onto the surface of the pDAN‐Au electrode in an acidic medium. The detection limit employing the anodic stripping differential pulse voltammetry was 9.0×10^?9 M for Se(IV) with 4.4 % of RSD. Satisfactory result for the determination of Se(IV) was acquired employing a certified standard urine reference material, SRM's 2670 (trace element in urine) with 4.1 ppb of SD.     

氢化物发生-原子荧光光谱法测定大蒜中砷和硒

采用氢化物发生-原子荧光光谱法测定大蒜中砷和硒。样品经硝酸和高氯酸消解,在盐酸(5+95)溶液中,加入溶于50g·L~(-1)氢氧化钠溶液的20g·L~(-1)硼氢化钾溶液,使其与溶液中砷及硒离子反应生成氢化物。分析中采用载气流量依次为800mL·min~(-1),600mL·min~(-1),屏蔽气的流量均为1000mL·min~(-1)。试样溶液中加入硫脲-抗坏血酸混合溶液作为还原剂。于仪器中引入试样溶液0.5mL,按选定的工作条件操作。砷及硒的质量浓度分别在0.04～0.40,1.00～10.0μg·L~(-1)范围内与其荧光强度呈线性关系,方法的检出限(3s/k)砷为0.017μg·L~(-1),硒为0.314μg·L~(-1)。分别加入两元素的标准溶液作回收试验,测得砷和硒的回收率分别在95.3%～104.4%和94.7%～105.2%之间。     

Preparation and Electrochemiluminescence of a Graphene Oxide/Selenium Nanocomposite

A novel amplification system for electrochemiluminescence (ECL) was developed by combining graphene oxide (GO) and Se nanoparticles, in which the chitosan (CHIT) was used as improver. Based on a series of experiments, the influencing factors and mechanism for ECL emission were determined. Under optimal conditions, the GO/Se nanocomposite produced an intense ECL emission and maintained long-term ECL stability. Significantly, the electrode modified with GO/Se nanocomposite was used to detect the biomolecule dopamine (DA), and showed a linear range from 0.1 to 100 µM, with a detection limit of 0.025 µM.