离子色谱-电感耦合等离子体质谱测定保健品中无机锗和锗-132

建立了离子色谱-电感耦合等离子体质谱法( IC-ICP-MS)测定液体保健品中无机锗和β-羧乙基锗倍半氧化物(锗-132)的方法,对液体或可溶于水的样品可以直接或稀释后进样.硒元素可能会带来干扰,可以选择72Ge作为定量同位素来避免.方法中无机锗和锗-132的定量限均为1.0μg/L,RSD均小于4.4％.对实际样品进行加标,无机锗回收率为91％～92％,锗-132回收率为104％～107％.样品的测定结果和湿法消解-电感耦合等离子体质谱检测出的结果相吻合.     

酸对微波消解-氢化物发生原子荧光光谱法测定食品中锗的影响

以微波消解为前处理手段,采用氢化物发生原子荧光谱法测定食品中的锗,研究了作为载液的磷酸体积分数和消解过程中残留硝酸对测定结果的影响. 磷酸体积分数从5%增加至30%时,标准曲线斜率缓慢上升. 认为10%~20%体积分数磷酸适宜作为原子荧光光谱法测锗的载液. 硝酸在样品中体积分数超过1%后,锗的荧光信号严重减弱. 优化条件后对市售大蒜样品进行加标试验. 为进一步确定对有机锗的消解效果,对某批次锗-132胶囊进行测定. 大蒜加标试验回收率为109.7%,胶囊测定值为标签标识值的81.4%. 两次试验结果均较为满意,说明方法具有可靠性.     

石墨炉原子吸收光谱法测定生物样品中微量锗

采用钼酸铵浸渍处理石墨管 ,研究了苯基荧光酮为螯合剂 ,四氯化碳为萃取剂 ,N ,N 二甲基甲酰胺 (DMF)为反萃取剂的萃取富集锗的新方法 ,用硝酸镍作为基体改进剂 ,石墨炉原子吸收光谱法直接测定各种生物样品中微量锗。方法绝对灵敏度 (1%吸收 )为 1.67× 10 - 11g ,相对标准偏差 3.5 4 %～ 6.15 % ,回收率为 96%～ 10 2 %     

高分辨电感耦合等离子体质谱法测定地质样品中的微量锗

应用高分辨电感耦合等离子体质谱法测定地质样品中的微量锗。研究了地质样品中不同酸消解方法、提取方法对测定锗的影响,以及在高分辨电感耦合等离子体质谱仪高、中、低分辨率模式下测定地质样品中锗的质谱行为。用氢氟酸-硝酸体系分解样品,硝酸提取,在中分辨率模式下进行测定。方法的检出限(3s)为10ng·g-1。方法用于10个国家标准物质中锗含量的测定,测定值与认定值相符,测定值的相对标准偏差(n=10)小于4.5%。     

有机锗(锗-132)的示差脉冲极谱研究

用示差脉冲极谱法,在pH1.30H_2SO_4和3,4-二羟基苯甲醛(DHB)底液中,获得了有机锗(Ge-132)和无机锗Ge(Ⅳ)二个配位吸附极谱波,波峰分别为E_P2-0.62V和E_pl=-0.47V(υs.AgCI/Ag),Ge-132浓度在2.6×10_(-5)～3.1×10_（-3）mol/L范围内,Ge(Ⅳ)浓度在 3.1×10_（-5）～2.1×10_（-4）mol/L范围内分别与峰电流星线性关系.利用该示差脉冲极谱法可同时测定Ge-132和Ge(Ⅳ),用于有机锗营养口服液中Ge-132和Ge(Ⅳ)的测定结果满意.还探讨了Ge-132极谱波的性质,测定了有关动力学参数.     

ICP-MS法测定磁致冷材料-钆硅锗系合金中Mo、 Mn、 Al、 V、 Ni、 Cu、 Ga、 Fe

建立了ICP-MS法测定磁致冷材料-钆硅锗系合金中Mo、 Mn、 Al、 V、 Ni、 Cu、 Ga、 Fe八种痕量杂质元素的方法, 并对ICP-MS工作参数及条件进行了优化. 方法的检出限为0.1～0.6 ng/mL, 测定下限为0.5～3 ng/mL, 回收率在95.5%～109%, 相对标准偏差(n=11)为1.3%～7.6%. 采用该方法对磁致冷材料-钆硅锗系合金实际样品进行了分析, 结果表明精密度和准确度均满足痕量分析的要求.     

苯基荧光酮荧光分光光度法测定痕量锗的研究

锗具有增血、抗炎症、抗衰老等多种医疗功能 ,因此 ,越来越受到人们的关注。荧光光度法测定微量锗已有报道[1～ 4] 。用苯基荧光酮荧光度法测定锗未见报道。本文利用苯基荧光酮与锗在醋酸 醋酸钠缓冲溶液中络合物形成速度快的优势 ,使其先在缓冲溶液中显色 ,然后在 0 .3ｍｏｌ ＬＨＣｌ介质中测定其荧光强度 ,用于粉煤灰中痕量锗的测定 ,得到满意结果。1　实验部分1 1　仪器与试剂ＲＦ - 5 4 0荧光分光光度计 (日本岛津 )。锗标准溶液 ( 1ｇ Ｌ) :称取 0 .1 0 0 0ｇ纯锗粉于 5 0ｍｌ小烧杯中 ,加入 5ｍｌＮａＯＨ ,再加入几滴 30 %Ｈ2 Ｏ2…     

微板式磁化学发光酶免疫分析法对人绒毛膜促性腺激素(HCG)的灵敏快速测定

以磁性酶免疫测量分析为模型,建立了微板式磁化学发光酶免疫分析法.利用3-(2′-螺旋金刚烷)-4-甲氧基-4-(3″-磷酰氧基)苯-1,2-二氧杂环丁烷(AMPPD)-碱性磷酸酶(ALP)化学发光体系对人绒毛膜促性腺激素(HCG)进行测定,测量的灵敏度较分光光度法提高了13倍.测定的线性范围为0.15～500 mIU/mL;批内变异系数(C.V.%)和批间变异系数(C.V.%) 均在18%之内;回收率在80%～116%之间;利用本法对血清样品进行了测定,并与其它化学发光免疫分析方法进行了比较,其相关系数为0.965.首次将酶免疫分析方法用于唾液中人绒毛膜促性腺激素(HCG)的测定,为建立非侵入式样品测定方法打下了基础.     

锗(Ⅳ)-邻苯二酚紫-钒(Ⅳ)催化极谱法测定食品中痕量锗

在0.2mol@L-1HClO4溶液中,锗(Ⅳ)-邻苯二酚紫(PV)-钒(Ⅳ)体系于峰电位-0.55V(vs.SCE)处产生一灵敏的吸附催化波.锗浓度在0～30ng@ml-1范围内与峰电流呈良好的线性关系,检出限为1.02ng@ml-1.方法用于食品中痕量锗的测定,结果满意.     

氯化物发生-电感耦合等离子体发射光谱法测定含锗保健品中无机锗

基于电感耦合等离子体发射光谱(ICP-OES)法研究了无机锗和有机锗在HCl介质中的氯化物发生情况.结果表明,有机锗(Ge-132)不形成氯化物,而无机锗在以浓 HCl为载流,载气压力0.14 MPa,样品溶液中HCl浓度为6 mol/L时能实现最佳的氯化物发生效率,由此建立了含锗保健品提取液中无机锗的选择性测定新方法...     

混合溶剂火焰原子吸收法直接测定原油中的镍

混合溶剂火焰原子吸收法直接测定原油中的镍刘广东袁存光张丙华刘文钦（石油大学（华东），山东东营２５７０６２）彭力（中国石油天然气总公司环保处，北京１００７２４）关键词原油，混合溶剂，无机盐标准，原子吸收法，镍测定原油中，微量元素镍、钒、铁、铜的存在对...     

Vortex grinding for mechanochemistry: application for automated supramolecular catalysis and preparation of a metal-organic framework

An automated grinding method based on a vortex mixer has been developed. The method enables simultaneous grinding and UV-irradiation, as well as in situ monitoring of solid-state reactivity. The method has been applied to a cocrystallization, supramolecular catalysis, and the preparation of a metal-organic framework.     

Simultaneous high-performance liquid chromatographic stability-indicating analysis of acetaminophen and codeine phosphate in tablets and capsules

A high-performance liquid chromatographic method has been developed for the simultaneous determination of acetaminophen and codeine phosphate for product stability studies, and release and dissolution testing of tablets and capsules. The reversed-phase method utilizes UV detection at 214 nm, a C18 column and requires a maximum of 10 min per analysis. The method has been validated for use with products containing as much as 500 mg of acetaminophen and as little as 7.5 mg of codeine phosphate. The known potential degradation products, p-aminophenol, codeine N-oxide, and codeinone are separated for quantitation simultaneous with the parent compounds. The method has been shown to be linear, reproducible, specific, sensitive and rugged.     

Analytical method for assessing exposure of greenhouse applicators to procymidone by gas chromatography and whole body dosimetry

Summary An analytical method for the determination of the potential and actual exposure of agricultural workers to procymidone has been developed. The methodology is based on the whole body technique, using Tyvek Pro-Tech and Sontara as sampling media, and uses hexane extraction, GC-ECD analysis and GC-MSD confirmation. The validation of the analytical method has been carried out incorporating the matrix of coverall in all steps when calculating parameters such as retention time window, limits of detection and quantification, linear ranges and precision. A field sampling strategy has also been developed and the method has been applied to the evaluation of the potential and actual dermal exposure of an applicator and an assistant in normal working conditions.     

Systematic enumeration of nonrigid isomers with given ligand symmetries

A new method for enumerating nonrigid isomers with rotatable ligands has been developed so as to take the symmetries of the ligands into consideration. The method has been based on extended partial cycle indices and has been applied to the enumeration of methyl ether derivatives, tetramethylallene derivatives, and 2,2-dimethylpropane derivatives. These results have been compared with the enumeration results of the corresponding promolecules. The factorization of terms in generating functions has been discussed so that the new method is capable of examining the relationship between promolecules and molecules quantitatively.     

Determination of Aluminium with 8-Hydroxyquinoline-5-Sulfonic Acid in Presence of A Cationic Surfactant by First and Second Derivative Synchronous Fluorimetry

Abstract

An analytical method has been developed for the fluorimetric determination of nanogram amounts of aluminium in solution. The method is based on the reaction of aluminium with B-hydroxyquinoli-ne-5-sulfonic acid in presence of hexadeciltrimethylammonium bromide as a surfactant agent. Synchronous scanned first and second derivative fluorimetry has been employed to increase the sensitivity of the method. The influence of reaction variables as well as instrumental parameters is discussed. The interference of various foreign ions has also been examined and in some cases eliminated or reduced by addition of 1, 10-phenanthroline.     

Technetium(99m)-tin colloid: A simple method for the preparation and evaluation

Effect of various amounts of reagents on the quality of^99mTc–Sn-colloid has been studied, and a simple and reproducible method for its preparation particularly suitable for hospital pharmacy has been developed. PVP has been used as a stabilizing agent. A quick method of its bio-distribution has also been described.     

High-throughput multiclass method for antibiotic residue analysis by liquid chromatography-tandem mass spectrometry

A simple and rapid method has been developed for the residue analysis of 39 antibiotics (tetracyclines, quinolones, penicillins, sulfonamides and macrolides) in foodstuffs of animal origin. The method combines an effective extraction technique, which uses water-methanol as extracting solvent, with ultra-high-pressure liquid chromatography-tandem mass spectrometry, allowing both confirmation and quantification in a single chromatographic run. The multiresidue method has been validated in chicken muscle matrix according to European Union Decision 2002/657/EC. It has been implemented as a routine method in a Public Health Laboratory, instead of the five plates test and LC methods previously used.     

Über die genauigkeit der schwefelbestimmungs-methode nach zimmermann

W. ZIMMERMANN's method of determining sulphur has been investigated and it has been found that the accuracy is not as great as has often been stated. It seems that the errors occur in the decomposition of the sample. In the modification of the method, recently published by ZIMMERMANN, the error is approximately compensated by the use of a titration procedure which gives too high results.     

Application of barycentric method for determination of free energy of liquid monodisperse system accomplishing diffusion

The barycentric method has been applied to determining the thermodynamic potential (the free energy) of a liquid rarefied monodisperse colloid system in which free unstationary diffusion under constant external conditions has been accomplished. Free energy at an arbitrary moment of time has been obtained as a function of horizontal mass center shift toward the cuvette cavity geometrical center of the liquid disperse system investigated. A very good coincidence between the numerical results from the proposed barycentric method and another classical thermodynamic method has been observed.