催化光度法测定大气中痕量钒

在乙酸－络蓝黑Ｒ－溴酸钾体系中，Ｖ（Ⅴ）催化溴酸钾氧化紫红我 的络蓝黑Ｒ褪色，褪色程度在０－０．８ｎｇ／２５ｍｌ范围内呈线性关系（沸水浴２５ｍｉｎ）。据此原理测定了大气悬浮粒子中的痕量钒。本法灵敏度高（０．３５ｌｇＡ０／ｎｇ／２５ｍｌ），检出限为０．０２／２５ｍｌ。样本中共存成分对测定无干扰。ＲＳＤ为３．４％０８．３％，回收率为８９．４－１１３．１％（平均值为１０１．４％）。对大气本样中钒进行测定     

烟草中Fe,Co一阶导数分光光度法同时测定的研究

本文研究了在ｐＨ４．０时，ｍｅｓｏ－四（４－磺酸基苯基）卟啉与铁、钴同时络合显色的反应条件以及一阶导数光谱行为。此体系一阶导数的灵敏度比零阶导数灵敏度高。Ｆｅ￣（３＋）～０．１８μｇ／ｍＬ、Ｃｏ￣（２＋）０～０．２４μｇ／ｍｌ，范围内符合比耳定律；检测限为：Ｆｅ￣（３＋）＝０．４８ｎｇ／ｍＬ，Ｃｏ￣（２＋）＝０．２ｎｇ／ｍＬ。回收率为：Ｆｅ９８．５％～１００．８％，Ｃｏ９９．２％～１０１．３％。此方法用于烟草中痕量Ｆｅ、Ｃｏ测定，与ＡＡＳ值相比较，结果令人满意。     

螯合树脂静态富集／电热蒸发（ETV）—ICP—AES测定铂族元素Pt,Pd和Os

用含氮，硫功能团的螯合树脂ＹＰＡ，进行静态吸附，含待测定元素的浓缩物制成悬浮体，采用悬浮体进样／电热蒸发等离子体原子发射光谱（ＥＴＶ－ＩＣＰ－ＡＥＳ）直接测定。方法的检出限分别为０．５，０．７和４．０ｎｇ／ｍＬ（对Ｐｔ，Ｐｄ和Ｏｓ）相对标准偏差分别为２．６％，４．７％和３．８％（ｎ＝１０，Ｐｔ：２．０ｍｇ／Ｌ，Ｐｄ：２ｍｇ／Ｌ，Ｏｓ：５．０ｍｇ／Ｌ）。应用本法对质标样进行了分析，测定值与标准值基本     

反相HPLC测定钒,铌,钽的2—（2—吡啶偶氮）—5—二乙氨基苯酚配合物

以２－（２－吡啶偶氮０－５－二乙氨基苯酚（ＰＡＤＡＰ）为柱前衍生试剂，在含０．１％酒石酸的１０ｍｍｏｌ／Ｌ（ｐＨ３．５）ＨＡｃ－ＮａＡｃ缓冲溶液的甲醇／水（５０∶５０，Ｖ／Ｖ）中（５８０ｎｍ检测），在Ｃ１８柱上于１１ｍｉｎ内实现了Ｖ、Ｎｂ、Ｔａ的同时分离及测定，检出限（Ｓ／Ｎ＝３）杰０．３４、０．２９、７．３０ｎｇ／ｍＬ．该法灵敏度高，用于矿样分析所得民推荐值相行，标准加入回收率为９９．０％～１０     

微波炉溶样恒温平台石墨炉原子吸收光谱法直接测定沉积物中痕量铍

研究了家用微波炉在自制的聚四氟乙烯密闭容器内,混酸（ＨＮＯ３２ｍｌ,ＨＦ２ｍｌ）分解样品,５ｇ．Ｌ＾－１Ａｌ（ＮＯ３）３作改进剂,直接定容后,在大量氢氟酸存在下,恒温平台石墨炉（ＳＴＤＰＦ）原子吸收光谱法测定水系沉积物中痕量铍。Ａｌ（ＮＯ３）３的存在,将铍的灰化温度提高到１６００℃,且消除溶解所引入的大量剩余氢氟酸干扰。方法快速、简捷、灵敏度高,再现性好,其检出限（３Ｓ）为０．１６ｎｇ．ｇ＾－１,铍的特征质量为０．７３ｎｇ／０．００４４Ａ,铍含量为１．１μｇ．ｇ＾－１的样品,取１０份同时测定,平均值为１．１６μｇ．ｇ＾＆－１,相对标准偏差为２．７７％。     

卡尔曼滤波在极谱分析中的应用——Sn（IV）,Pb（II）,In（III）,Cd（II）…

利用卡尔曼滤波（ＫＦ）技术，对互相干扰的Ｓｎ（Ⅳ），Ｐｂ（Ⅱ），Ｉｎ（Ⅲ），Ｃｄ（Ⅱ）体系进行了定量测试研究，在５．００×１０＾５～３．００×１０＾－４ｍｏｌ．Ｌ＾－１的浓度范围内，各组分测试的相对误差为－４．０％～３．８５％，对大理石抛光粉管理样中的Ｓｎ（Ⅳ），Ｐｂ（Ⅱ）进行了测定，结果与ＩＣＰ－ＡＥＳ结果表明，回收率在９５．０％～１０４％之间，为保证ＫＦ的精度，使用两个监控出口。数据说明效果良     

树脂预浓集──电感耦合等离子体原子发射光谱在线分析痕量元素Cd、Cr、Cu、Ph、Zn

本文采用微型高效富集柱对膦酰胺树脂、Ｈ１０９树脂、苯乙烯多胺基膦酸树脂和膦酸胺混杂树脂对Ｃｄ、Ｃｒ、Ｃｕ、Ｐｈ、Ｚｎ等元素预富集性能进行了实验，并对浓集、洗脱及测定的条件进行选择，建立了一套在线的痕量元素－ＩＣＰ—ＡＥＳ多元素同时测定体系，从而大大提高了分析灵敏度，降低了检出限近一个数量级，Ｃｄ、Ｃｒ、Ｃｕ、Ｐｈ、Ｚｎ在不同树脂下的检出限分别为０．２～０．５ｎｇ／ｍｌ，０．３～０．６ｎｇ／ｍｌ，＜１．７ｎｇ／ｍｌ，１．５～２．８ｎｇ／ｍｌ，０．１～０．２ｎｇ／ｍｌ。利用此体系对贻贝、牡蛎、桃叶、茶叶等标样的分析结果与推荐值相符合。     

钴（Ⅱ）—β—巯基丙酸—NaNO2体系的极谱化波研究

在ｐＨ３．８的Ｈ２ＳＯ４－ＮＨ４Ａｃ介质中，Ｃｏ（Ⅱ）－β－巯基丙酸（ＭＰＡ）－ＮａＮＯ２体系产生－灵敏的极谱催化波，峰电位在－０．８４Ｖ（ｖｓ．ＳＣＥ）钴浓度在０．０２～１００ｎｇ／ｍＬ范围内与峰电流呈线性关系，检出限为０．０１ｎｇ／ｍＬ。本文对极谱波的性质和机理进行了初步探讨，本法用于土壤中总钴和有效钴的测定，结果满意。     

新有机试剂BTASPAP水相光度法测定Fe（Ⅲ）

研究了新有机试剂２－（２－苯并噻唑偶氮）－５－磺丙氨基苯酚（简写ＢＴＡＳＰＡＰ）与Ｆｅ（Ⅲ）的水相显色反应。Ｆｅ（Ⅲ）在ｐＨ３．０～４．２范围内与ＢＴＡＳＰＡＰ形成组成比为１：３的稳定的，易溶于水而又带负电荷的蓝紫色配合物，其表观摩尔吸光系数ε５８０为４．０×１０＾４，Ｆｅ（Ⅲ）在０～４０μｇ／２５ｍｌ范围服从比耳定律，所拟方法用于纯铝和铝合金标样中铁的测定，结果满意。     

痕量铼的同位素稀释中子活化分析

将同位素稀释法的准确性与中子活性分析（ＮＡＡ）的高灵敏度相结合，建立了一种新的痕量铼的测试方法，实验中对Ｒｅ的检出限为０．００４ｎｇ，全流程空白为０．０５ｎｇ，地于Ｒｅ含量为６４ｎｇ／ｇ的样品，在取样量为５０ｍｇ时，单次测定误差（２σ）为３．１％，测定Ｒｅ一为３０ｎｇ／ｇ的样品，本方法的２σ在３％以内，４次分析的ＲＳＤ为４．１％，而采用一般的ＮＡＡ，结果偏低约２０％，并且ＲＳＤ大于５％。     

流动注射-阴离子交换预浓集-电感耦合等离子体发射光谱法检测痕量元素——砷、硒、钼、硫、铬

本文研究了阴离子交换树脂D296对待测元素As、Se、Mo、S、Cr的预浓集性能,并与改进的流动注射(FI)(双流路)相结合,建立了一套新型、高效的FI-阴离子交换-ICP-AES分析体系。从而极大地提高了分析的频率和灵敏度,分析速度可达每小时14个样品。As、Se、Mo、S、Cr各元素的检测限分别为13.0 ng/ml、25.2 ng/ml、2.04 ng/ml、6.19 ng/ml、3.64ng/ml。利用此体系检测了标准土壤、头发、牛肝粉等,结果与标准值均很接近。     

Determination of zinc by flow injection with fluorimetric detection in a micellar medium

A room-temperature flow injection spectrofluorimetric method is presented for the determination of Zn(II), based on the use of salicylaldehyde thiocarbohydrazone in the presence of Triton X-100 and sodium acetate-acetic acid buffer. Various physical and chemical variables affecting the reaction in the flow system were evaluated. The proposed method is very selective. The calibration graph is linear over the range 10-1000 ng/ml, with a detection limit of 5 ng/ml and a relative standard deviation at the 50 ng/ml level of 1.8 %. The method was successfully applied to the determination of Zn(II) in drinking waters and biological samples.     

Determination of zinc by flow injection with fluorimetric detection in a micellar medium

A room-temperature flow injection spectrofluorimetric method is presented for the determination of Zn(II), based on the use of salicylaldehyde thiocarbohydrazone in the presence of Triton X-100 and sodium acetate-acetic acid buffer. Various physical and chemical variables affecting the reaction in the flow system were evaluated. The proposed method is very selective. The calibration graph is linear over the range 10–1000 ng/ml, with a detection limit of 5 ng/ml and a relative standard deviation at the 50 ng/ml level of 1.8 %. The method was successfully applied to the determination of Zn(II) in drinking waters and biological samples.     

Enhancement of the fluorescence of the zinc-morin complex by a non-ionic surfactant

A method is described for the fluorimetric determination of zinc, based on formation of a zinc-morin complex in the presence of a non-ionic surfactant. The complex has practically no fluorescence in the absence of surfactant, but the addition of Genapol PF-20 (non-ionic surfactant, ethylene oxide-propylene oxide condensate) makes possible the fluorimetric determination of low concentrations of zinc as it enhances the fluorescence of the complex about 75-fold. Maximum fluorescence is produced at pH 4.7 +/- 0.2 (acetic acid-acetate buffer), with 1.5% surfactant and 0.009% morin. The fluorescence is excited at 433 nm and measured at 503 nm. The calibration graph is linear up to 150 ng/ml zinc concentration and the detection limit is 3 ng/ml. The relative standard deviation (11 replicates) is 2.4% for zinc at 20 ng/ml concentration and 1.7% for 100 ng/ml. Of 29 ions studied, Al(3+), Be(2+), Zr(4+) and Cd(2+) strongly increase the fluorescence of the system, and Fe(3+), Ni(2+), Cu(2+), Ti(IV) and Co(2+) decrease the fluorescence signal.     

Flow injection determination of chromium(III) by pyrogallol chemiluminescence

A flow injection method is proposed for the determination of nanogram amounts of chromium(III) using a pyrogallol chemiluminescence system. It is based on its catalytic effect on the oxidation of pyrogallol with periodate at a neutral medium. The addition of 3-(N-morpholino)propanesulphonic acid to the reaction system increased the chemiluminescence signal for chromium(III). The present method allows the determination of 5-100ng/ml of chromium(III). The relative standard deviation of 2.2% (n = 10) was obtained at 20 ng/ml of chromium(III) and the detection limit (signal-to-noise ratio = 2) was 1 ng/ml with the sampling frequency of 25/hr.     

Flow Injection Spectrofluorimetric Determination of Terbium (III) Based on Solubilizing its Ternary Complex in Micellar Solution

Abstract

A flow injection spectrofluorimetric method has been developed for the determination of terbium (III) based on solubilizing its ternary complex with pi valoyitrifluoroacetone (PTA) and trioctylphosphine oxide(TOPO) in micellar solution of nona (oxyethylene) dodecyl ether (BL-9EX). Accuracy and reproducibility are good up to 16 ng/ml of terbium (III) and 80 samples per hour can be analyzed. The relative standard deviation was less than 1.0 %. No interferences from 20-fold excesses of 11 rare earth ions were observed.     

Capillary column gas chromatographic method using electron-capture detection for the simultaneous determination of nicardipine and its pyridine metabolite II in plasma

A rapid, specific and direct method based on capillary column gas chromatography with electron-capture detection is described for the simultaneous determination of nicardipine, a new calcium antagonist, and its pyridine metabolite II in human plasma. In this method, the nicardipine, its pyridine metabolite II and internal standard are extracted from the plasma and then partially purified by acid-base partitioning prior to the final injection onto the capillary column gas chromatograph for quantification by means of an electron-capture detector. The quantification limit of the method is 1 ng/ml of plasma for both nicardipine and its pyridine metabolite II. The coefficients of variation for nicardipine and the pyridine metabolite II at concentrations of 1-50 ng/ml are less than 7% and less than 9% (n = 4), respectively. The method has been validated against a previously developed high-performance liquid chromatographic method (sensitivity 5 ng/ml).     

Dual-sensitive probe 1-imidazole-2-(5-benzoacridine)-ethanone for the determination of amines in environmental water using HPLC with fluorescence detection and online atmospheric chemical ionization-mass spectrometry identification

Dual-sensitive probe of 1-imidazole-2-(5-benzoacridine)-ethanone (IBAE) for the determination of free amines with fluorescence detection and online highly sensitive atmospheric chemical ionization-mass spectrometry identification (APCI-MS) has been developed. 2-(Benzoacridine)-5-acetic acid (BAAA) reacts with coupling agent N,N′-carbonyldiimidazole (CDI) to form a highly activated amide intermediate 1-imidazole-2-(5-benzoacridine)-ethanone (IBAE), which is dual-sensitive probe. The amide intermediate (IBAE) reacts preferably with amines in dimethylformamide (DMF) solvent to give the high yields of derivatives. IBAE-amine derivatives are not only sensitive to fluorescence but also to MS ionizable efficiency. The percent ionization δ values change from 0 to 57.32% in aqueous acetonitrile and from 0 to 62.14% in aqueous methanol. The relative standard deviations of the peak areas with fluorescence detection for each amine are <1.24% (40 ng/ml, n = 6). The fluorescence detection limits (at a signal-to-noise ratio of 3) are in the range of 0.15-0.50 ng/ml. The online APCI-MS detection limits are in the range of 2.07-8.51 ng/ml (at a signal-to-noise ratio of 3). Therefore, the facile IBAE intermediate derivatization allowed the development of a highly sensitive and specific method for the quantitative analysis of trace levels of amines in environmental water.     

Flow-injection chemiluminescence determination of enalapril maleate in pharmaceuticals and biological fluids using tris(2,2'-bipyridyl)ruthenium(II).

A chemiluminescence (CL) method using flow injection (FI) has been investigated for the rapid and sensitive determination of enalapril maleate. The method is based on the CL reaction of the drug with tris(2,2'-bipyridyl)ruthenium(II), Ru(bipy)3(2+) and acidic potassium permanganate. After selecting the best operating parameters, calibration graphs were obtained over concentration ranges of 0.005-0.2 microg/ml and 0.7-100 microg/ml with a detection limit (S/N=2) of 1.0 ng/ml. The average % found was 99.9 +/- 0.7 and 100.2 +/- 0.3 for the two concentration ranges respectively. %RSD (n=10) for 5.0 microg/ml was 0.44. The method was successfully applied to the determination of enalapril maleate in dosage forms and biological fluids without interferences.