氢化物发生-原子荧光光谱法测定富硒酵母中的有机硒和无机硒

建立了氢化物发生-原子荧光光谱法测定富硒酵母中硒的分析方法。研究了仪器的工作条件、试剂对硒测定的影响;探讨了消化试剂对样品消化的影响和共存离子的干扰及消除。在优化的工作条件下,硒的检出限为0.078μg/L,相对标准偏差为0.45%,线性范围为0~100μg/L。应用该方法检测了不同富硒酵母中的总硒含量为1.40~3.20 mg/g;其中,有机硒含量为1.30~2.97 mg/g,加标回收率为95.4%~104.3%。     

双通道原子荧光光谱法同时测定土壤中的砷和汞

对现有国标检测方法(GB/T 22105.1-2008和GB/T 22105.2-2008)进行改进,采用王水水浴浸提-双通道原子荧光光谱法同时测定土壤样品中砷、汞的含量。采用土壤国家一级标准物质GSS-3,GSS-8,GSS-9与山西农田土壤样品为试验对象,筛选得到检测砷、汞元素含量最佳实验条件及仪器工作条件。砷、汞的质量浓度分别在0~150μg/L,0~2μg/L范围内与荧光强度成良好的线性关系,线性相关系数均大于0.999,砷、汞的检出限分别为0.021,0.0015 mg/kg。测定结果的相对标准偏差为1.81%~4.64%(n=8),砷、汞的样品加标回收率分别为92.7%~103.0%,82.0%~95.5%。经国家一级标准物质验证,该法检出限、准确度和精密度均满足检测要求。改良后的方法可以同时准确、快速地测定土壤中砷、汞,极大地提高了工作效率,可以更好地适应当前大量的土壤分析工作。     

氢化物发生-原子荧光光谱法测定高纯阴极铜中硒、碲

本文报道了采用氢化物发生-原子荧光光谱法(HG-AFS)测定高纯阴极铜中硒、碲。实验考察了盐酸、三氯化铁的浓度对氢化物发生效率的影响,探讨了铜和其它共存元素的干扰情况。该法测定硒、碲的检出限分别为0.27μg/L、0.11μg/L,加标回收率分别为94.9%～114.0%、91.8%～105.3%,精密度为1.5%～7.8%。     

流动注射原子吸收光谱法测定富硒天麻、葡萄及大米中的硒

建立了流动注射氢化物发生-原子吸收光谱法测定富硒天麻、葡萄及大米中硒的方法。测定硒的线性范围为0．33μg/L-50μg/L，相对标准偏差小于3％，加标回收率为93％-106％。方法已广泛应用于实际样品中微量硒的测定。     

氢化物发生原子荧光法测定聚氯化铝中的砷含量

建立了氢化物发生原子荧光法测定聚氯化铝中砷含量的检测方法。将聚氯化铝样品用硫酸溶解,蒸至近干,用氢化物发生原子荧光法测定其中的砷含量。在最佳测定条件下,砷的质量浓度在0~10.0μg/L范围内与荧光强度呈良好的线性关系,相关系数r=0.999 3,砷的检出限为0.03μg/g,样品加标回收率为82.5%~90.0%,测定结果的相对标准偏差为1.5%~1.9%。该法具有快速、准确、灵敏度高等优点。     

微波样品消解-氢化物发生-双通道原子荧光光谱法同时测定家禽内脏中硒和锗

应用氢化物发生-原子荧光光谱法同时测定家禽内脏中的硒和锗含量。采用微波消解法用硝酸和过氧化氢对样品进行消解,以硫脲作为预还原剂,以溶于5g·L-1氢氧化钾溶液中的20g·L-1硼氢化钾溶液作为还原剂。硒、锗的质量浓度均在500μg·L-1范围内与其荧光强度呈线性关系,检出限(3s/k)分别为0.001 08μg·L-1和0.017 1μg·L-1。硒、锗的加标回收率分别在98.9%~102%,97.4%~102%之间。     

双通道原子荧光法同时测定水中砷和硒

采用双通道原子荧光法同时测定水中的砷和硒含量。以氢氧化钾–硼氢化钾溶液为还原剂,以硫脲–抗坏血酸–盐酸溶液为介质,在0~10μg/L范围内,砷、硒的质量浓度分别与荧光强度呈良好的线性,线性相关系数大于0.999,检出限分别为0.016,0.032μg/L。砷、硒测定结果的相对标准偏差为1.4%~1.5%(n=11),加标回收率在98.0%~102.0%之间。该方法操作简单、精确度高,适合于水中砷和硒含量的测定。     

微波消解-电感耦合等离子体质谱法(ICP-MS)测定锌精矿中的铟和锗

提出了通过微波消解法消解锌精矿,用电感耦合等离子体质谱法(ICP-MS)测定锌精矿中铟和锗含量的方法。对样品进行了分解方式的选择和质谱干扰扣除以及加标回收实验,实验结果表明,铟的加标回收率在96.26%~98.70%,锗的加标回收率在99.60%~101.0%,铟的检出限为0.001μg/g,锗的检出限为0.02μg/g,验证了方法的可靠性。     

断续流动氢化物发生原子荧光法测定富硒食品中的微量硒

建立了断贯流动氢化物发生原子荧光法测定富硒食品中微量硒的方法。样品用硝酸高氯酸混酸消化，在优化的实验条件下，标准曲线的线性范围为0-100μg/L，相关系数为0.9999。检测限0.06545μg/L。应用于测定鸡蛋，富硒米和富硒盐中微量硒的测定。回收率分别为90.6%,98.5%和104.3%。     

湿法消解-原子荧光光谱法测定化妆品中的铅

采用硝酸-高氯酸处理样品,以氢化物发生-原子荧光光谱法测定了化妆品中的铅。在最佳条件下,铅的线性范围为0~200μg/L,方法检出限为0.0846μg/L,样品加标回收率为95.08%~102.6%,相对标准偏差为0.759%~1.528%(n=7)。     

预富集-氢化物发生原子吸收光谱法测定饮料中的痕量铅

原子吸收光谱法测定水样中的痕量元素是应用得最广泛的方法之一[1]。有时需采用多种方法对水样中的痕量元素进行富集。其中一类方法是基于待测元素配合物可以最终定量富集于少量颗粒上,过滤收集这些颗粒,然后制成小体积的、可直接用原子吸收光谱法测定的悬浊液。特定的配位剂分     

石墨消解–原子荧光法测定土壤中的汞和砷

采用石墨消解法对土壤样品进行预处理,用原子荧光光度法测定样品中汞和砷的含量。汞的质量浓度c在0.00~1.00μg/L范围内与荧光强度I线性相关,回归方程为I=849.47c–22.356,相关系数r2=0.999 9,检出限为0.001 8μg/g。砷的质量浓度在0.00~10.00μg/L范围内与荧光强度线性相关,回归方程为I=107.22c–28.994,相关系数r2=0.999 9,检出限为0.009 9μg/g。实际土壤样品5次平行测定汞和砷的相对标准偏差分别为6.2%~15.2%,0.8%~9.9%,用本法对黄土标准样品进行测定,测定结果在标准值允许范围内。     

电热消解-电感耦合等离子体质谱(ICP-MS)法测定土壤中镱铪钽钨四种高能稀土元素

镱(172 Yb)、铪(178 Hf)、钽(181 Ta)、钨(182 W)四种稀土元素质量数均高于170,第一电离能分别为601、656、759、767 kJ/mol,高于平均电离能486 kJ/mol,属于难电离元素,且在土壤中含量较低。通过选择合适的消解体系,采用碰撞模式去除多原子离子干扰,选择193 Ir内标校正基体干扰,建立了电热消解-电感耦合等离子体质谱法测定土壤中镱铪钽钨四种高能稀土元素的方法。4种元素校准曲线的线性均大于0.999,检出限在0.05~0.5μg/g,用土壤标准物质GSS-8、GSS-13进行验证,平均相对标准偏差(RSD)在3.2%~12.4%,加标回收率为88%~115%,各元素的测定值与标准值吻合。     

加速溶剂萃取-固相萃取-气相色谱串联质谱测定土壤中的乙草胺

提出一种准确、高效测定土壤中乙草胺的分析方法。优化方法后,土壤样品经过预处理,加速溶剂萃取(ASE),固相萃取柱(SPE)净化,样液经气相色谱串联质谱仪(GC-MS/MS)测定,用空白样品基质液配标,浓度在0.005~0.2μg/mL范围内,线性相关系数达0.9998。对空白土壤样品进行0.5,5,20μg/kg 3个水平加标(n=6),平均回收率为89.3%~102.1%,RSD范围为2.9%~4.1%。此方法可用于实际样品测定。     

石墨消解-原子荧光光谱法测定土壤中的总硒

为准确定量土壤硒总量,提出以逆王水(1+1)-石墨消解法消解土壤,氢化物原子荧光光谱法(HG-AFS)测定土壤总硒含量的方法。其中,对消解方式、消解时间和仪器条件进行了探讨,确定最优检测条件。称取0.2g土壤样品加入5mL逆王水(1+1),于石墨消解仪120℃消解1.5h,冷却至室温后用超纯水定容至25mL,原子荧光光度计测定总硒含量。结果显示,9种土壤标准物质测定值都在理论值范围内,其相对标准偏差为2.6%,加标回收率为92.3%～110%,检出限为0.68ng/L。方法测定结果准确,操作简单、实验周期短、成本低、安全。     

电感耦合等离子体质谱法测定金银花中6种有毒元素

建立电感耦合等离子体质谱法同时测定金银花中铅、镉、铬、镍、铜、砷6种有毒元素含量。采用微波消解法进行前处理,以钪、铟、铋3种元素作为内标物,用电感耦合等离子体质谱法对50批金银花样品中铅、镉、铬、镍、铜、砷6种有毒元素含量进行测定,以内标法定量,并应用SPSS软件对测定值进行统计学分析。6种有毒元素的质量浓度在0~300μg/L范围内线性良好,相关系数均不小于0.9997。6种有毒元素的检出限为0.003~0.020 mg/kg,样品加标回收率为80.0%~111.0%,相对标准偏差为0.71%~3.82%(n=6)。50批金银花样品中共计有14批样品有毒元素含量超出2015年版《中华人民共和国药典》规定,超标率为28%。聚类分析将50批样品分为3大类。该方法操作简单,灵敏度高,专属性好,可准确快速地同时测定金银花中多种有毒元素含量,可作为中药材品质及安全性监管的技术手段。     

Determination of total selenium and selenium distribution in the milk phases in commercial cow’s milk by HG-AAS

A procedure has been developed for determining the selenium in cows milk using hydride generation–atomic absorption spectrometry (HG-AAS) following microwave-assisted acid digestion. The selenium distributions in milk whey, fat and micellar casein phases were studied after separating the different phases by ultracentrifugation and determining the selenium in all of them. The detection limits obtained by HG-AAS for the whole milk, milk whey and micellar casein were 0.074, 0.065 and 0.075 g l^–1, respectively. The accuracy for the whole milk was checked by using a Certified Reference Material CRM 8435 whole milk powder from NIST, and the analytical recoveries for the milk whey and casein micelles were 100.9 and 96.9%, respectively. A mass balance study of the determination of selenium in the different milk phases was carried out, obtaining values of 95.5–100.8%. The total content of selenium was determined in 37 milk samples from 15 different manufacturers, 19 whole milk samples and 18 skimmed milk samples. The selenium levels found were within the 8.5–21 g l^–1 range. The selenium distributions in the different milk phases were studied in 14 whole milk samples, and the highest selenium levels were found in milk whey (47.2–73.6%), while the lowest level was found for the fat phase (4.8–16.2%). A strong correlation was found between the selenium levels in whole milk and the selenium levels in the milk components.     

氢化物发生–原子荧光法测定无机盐类食品添加剂中的铅

建立了氢化物发生–原子荧光光谱法测定无机盐类食品添加剂中铅的分析方法。考察了仪器工作条件、载流的酸度、还原剂浓度、氧化剂和掩蔽剂的用量以及共存元素对测量体系的影响。在优化实验条件下,该方法的线性范围为0~60μg/L(r=0.999 7),方法检出限为3.3μg/kg。以5种无机盐类食品添加剂为例,加入铅的质量浓度分别为12,24,48μg/L,每种浓度均进行6次平行测定,铅的回收率在95.0%~103.8%之间,测定结果的相对标准偏差为1.05%~2.71%(n=6)。该法适用于食品添加剂的质量控制和日常检测。     

Inter-method comparison for the determination of antimony and arsenic in peat samples

Four analytical approaches, based on different physical principles, for the determination of antimony (Sb) and arsenic (As) in ancient peat samples were critically evaluated: (a) open vessel digestion/hydride generation-atomic absorption spectrometry (HG-AAS), (b) closed-pressurized digestion in a microwave oven followed by sector field-inductively coupled plasma-mass spectrometry (SF-ICP-MS), (c) digestion in a microwave autoclave and subsequent quadrupole-inductively coupled plasma-mass spectrometry (Q-ICP-MS) measurements and (d) instrumental neutron activation analysis (INAA). The quality control scheme applied, always included the use of adequate plant reference materials to ensure the accuracy and precision of the analytical procedures. Additionally, two internal peat reference materials were analyzed using all four analytical approaches, generally showing good agreement for both elements. Method detection limits for As and Sb provided by all procedures were approximately 5 and 2 ng g⁻¹ which is sufficiently low for the reliable quantification of both elements in ancient, pre-anthropogenic peat samples. A comparison of As and Sb concentrations in a set of peat samples determined by INAA, HG-AAS and SF-ICP-MS revealed that INAA underestimated the values in a systematic manner, whereas HG-AAS and SF-ICP-MS data agreed very well. Best precision of the results was obtained by analytical procedures involving HG-AAS or Q-ICP-MS and varied from 3.6 to 4.3% and 7.1 to 7.5% for As (at about 0.5 μg g⁻¹) and Sb (at about 0.1 μg g⁻¹), respectively. The highest sample throughput (40 samples per run accomplished in 2 h) combined with low risk of sample contamination could be realized in the high-pressure microwave autoclave. The amount of sample required by all approaches was 200 mg, except for INAA which needed at least 25 times more sample mass to achieve comparable detection limits. For the quantification of As and Sb, inductively coupled plasma-mass spectrometry (ICP-MS) was preferred over INAA and HG-AAS, mainly because (a) less sample is needed and (b) As and Sb can be determined simultaneously. In addition, ICP-MS offers the possibility to measure concurrently a wide range of other elements which also are of environmental interest.