A complete inorganic survey study to reveal and study sensitometric deviations in photographic AgX emulsions by inductively coupled plasma mass spectrometry

Abstract

Inductively coupled plasma mass spectrometry (ICP-MS) offers excellent possibilities for multi-element trace analysis of photographic silver halide emulsions. In the present study, an analytical method was developed for the simultaneous determination of essential elements, such as ruthenium, rhodium, iridium and gold, in small emulsion samples, both overall as well as on the crystal surface. Sample preparation was performed by dissolving the silver halide emulsion into a self-made acid fixer. In-house standard reference emulsion material was prepared to verify the accuracy and precision of the quantitative method. The final result is a quantitative method for the selected elements with a precision of typically 1 per cent or better with relative standard deviations of 0.1–2.0 per cent. Detection limits were in the range 0.01–0.03 μg/kg. Using the scanning mode option of the instrument, the complete mass spectrum can be generated. Overlays can be made of two mass spectra and used as ‘fingerprints’ to reveal sensitometric deviations. Hence elemental trends can be traced or anomalies pinpointed in large batches of samples.     

Rhodium Determination in Environmental Objects by the Catalytic Method According to the Reaction of Sulfarsazen Oxidation with Periodate

A procedure for decomposing samples and determining rhodium in environmental objects by the catalytic method according to the reaction of sulfarsazen oxidation with periodate is proposed. The accuracy of the results is confirmed by determining rhodium using the method of inductively coupled plasma mass spectrometry. It is established that the rhodium content in the samples of road dust in Moscow is 0.01–0.04 g/t depending on the place of sampling. The standard deviation of repetition of the results of rhodium determination does not exceed 0.05.     

地下水中Fe的ICP-MS检测和修正方法

提出了使用电感耦合等离子体质谱法检测地下水中Fe的过程中,标准系列溶液与样品溶液由于基体不同,随雾化气流量变化时所受到的影响程度不一致,对样品中Fe的分析结果的准确性和可靠性产生不利影响。同时提出在线内标溶液含有一定浓度的Fe,并把相应的检测值带入分析结果,对低含量样品中Fe的分析结果的准确性和可靠性产生不利影响。通过实验研究,说明了使用监控样技术对这两个问题进行修正能够获得良好效果,并且相应说明了监控样的制备方法、保存条件和使用期限及对在线内标溶液的处理方法。在这个基础上,建立了新的电感耦合等离子体质谱法检测地下水中Fe的方法,重新确定了方法参数。方法的检出限(DL)达到18.9ng/mL。方法精密度(RSD)为6.11%～8.56%(n=12)。加标回收率为97.55%。     

Precise determination of element/calcium ratios in calcareous samples using sector field inductively coupled plasma mass spectrometry

A new method was developed for rapid and precise simultaneous determination of Mg/Ca, Sr/Ca, Mn/Ca, Cd/Ca, Ba/Ca and U/Ca ratios in foraminiferal shells using sector field inductively coupled plasma mass spectrometry (ICPMS). Element/calcium ratios were determined directly from intensity ratios using external, matrix-matched standard to correct for instrumental mass discrimination. Because of large differences in the abundance of chemical constituents of the foraminiferal shell, major elemental ratios were determined in analog mode (using (24)Mg, (43)Ca, (44)Ca, (55)Mn, and (88)Sr) whereas trace elemental ratios were determined in pulse-counting mode (using (111)Cd, (138)Ba, (238)U, and the low-abundance (46)Ca isotope). Matrix-induced variations in mass discrimination over a calcium concentration range of 2.0-24.5 mM were observed only for Mg/Ca and Cd/Ca ratios. However, these effects are negligible if the samples and standard calcium concentration are within a factor of 2-3. Multiratio method reproducibility was better than previously reported for other ICPMS methods yielding precision (1σ) of Sr/Ca = 0.45%; Mg/Ca = 0.45%, Mn/Ca = 0.8%, Cd/Ca = 1.7%, Ba/Ca = 0.7%, and U/Ca = 1.4% for foraminifera samples as small as 25 μg. Using this approach for a single-ratio analysis, Sr/Ca ratios were determined with precision of 0.06% (1σ) on carbonate samples as small as a single foraminifera shell (<10 μg). The new method is more sensitive, more precise, and simpler to use than previously available ICPMS techniques. It provides an efficient tool for simultaneous determination of several elemental ratios of paleoceanographic interest in a single foraminiferal sample, thereby reducing overall sample size requirement and analysis time.     

Evaluation of inductively coupled plasma mass spectrometry as an elemental detector for supercritical fluid chromatography

Supercritical fluid chromatography coupled with inductively coupled plasma mass spectrometry shows high potential for the determination at ultratrace levels of organometallic compounds of environmental interest. In this study the determination of organotin compounds at ultratrace levels is demonstrated. In this work a supercritical fluid chromatography/inductively coupled plasma mass spectrometry (SFC/ICPMS) interface was developed. Separation of tetraalkyltin compounds shows detection levels in the subpicogram range (0.034 pg for tetrabutyltin; 0.047 pg for tetraphenyltin). The linear ranges are over 3 orders magnitude (1-1000 pg). The reproducibility of sample injections are better than 5% RSD.     

Trace Element Microanalysis in Iron Meteorites by Laser Ablation ICPMS

A laser ablation microanalysis system has been developed that can analyze trace elements with a sensitivity in the ppb range, using a CETAC LSX-200 laser ablation system with a Finnigan Element. This capability has been applied to a set of iron meteorites to demonstrate the laser microprobe's analytical capability for the determination of platinum group elements (PGEs) with a spatial resolution of ～20 μm, comparable to that of dynamic secondary ion mass spectrometry (SIMS). The laser is shown to provide an accurate means of solid sampling for magnetic sector inductively coupled plasma mass spectrometry (ICPMS), allowing the determination of bulk metal composition, chemical zoning within the sample, and depth profiling. Recovery of the chemical zoning in taenite lamellae was achieved for Ru, Rh, and Pd, which was not previously possible using SIMS. The methods presented here show that magnetic sector ICPMS can be successfully coupled to a laser ablation system, providing the advantages of higher sensitivity of the sector instrument, low background count rates (<0.1 counts/s), and flat-topped spectral peaks, while minimizing tradeoff against the speed of data acquisition required to handle the transient signals from the laser ablation system.     

高效液相色谱串联等离子体发射质谱分析食用色素赤藓红中痕量碘化钠

建立了高效液相色谱串联等离子体发射质谱测定食用色素赤藓红中痕量碘化钠的方法,选用0.1mol/L乙酸铵溶液（pH=6.4）和甲醇为流动相,采用反相液相色谱柱ODS-C18分离了碘化钠和赤藓红,该方法的定量限与检测限分别达到10.0ng/g和 3.0ng/g,线性范围为 10~1000ng/g,精密度的范围为0.37%~0.43%,加标回收率变化范围为97.5%~99.7%。并将此方法应用到食用色素赤藓红中碘化钠的测定分析,评价了方法的不确定度。最终合成标准不确定度u_c=1.94％,扩展不确定度U=3.9%（k=2）。     

Determination of pu isotopes in seawater by an on-line sequential injection technique with sector field inductively coupled plasma mass spectrometry

An on-line sequential injection (SI) system combined with sector field inductively coupled plasma mass spectrometry was developed for the determination of ultratrace level 239Pu and 240Pu in seawater. The potential of this method is the substantial reduction of a sample volume and rapidity in the determination of Pu isotopes. A chemical purification and preconcentration of Pu isotopes were accomplished by the on-line SI system with two microcolumns of solid-phase extraction resins, Sr-Spec and TEVA-Spec. The MCN-6000 microconcentric nebulizer was used as a sample introduction system because of low interference effect and good sample utilization. With this method, it was possible to analyze ultratrace levels of Pu isotopes in only 5 L of surface seawater with an analysis speed of 4 h/sample. The precision of the measurement for the 239Pu and 240Pu was less than 3.4 (n = 7) and 5% (n = 7) for 5 L of seawater. The detection limits for 239Pu and 240Pu were 0.64 (1.5 microBq/mL) and 0.19 fg/mL (1.6 microBq/mL), respectively. The accuracy of this method was verified by using the reference seawater (IAEA-381) as well as by the comparison with the a-spectrometry.     

A Validated Stability Indicating LC Method for Nateglinide

ABSTRACT

A simple, isocratic, rapid and accurate reverse phase high-performance liquid chromatography (RP-HPLC) method was developed for the quantitative determination of Nateglinide. The developed method is also applicable for determination of related substance in bulk drugs. The chromatographic separation was achieved on a Hypersil C18 (250 × 4.6 mm 5 μm) column using aqueous mixture of 0.025 M potassium hydrogen phosphate and 0.1% triethyl amine, v/v (pH 3.0 with dilute phosphoric acid)—methanol (25:75, v/v) as a mobile phase. Solution concentrations were measured on a weight basis to avoid the use of an internal standard. The chromatographic resolutions between Nateglinide and its potential impurities A and B were found to be greater than four. Forced degradation studies were performed for Nateglinide using acid (0.5 N hydrochloric acid), base (0.5 N sodium hydroxide), oxidation (3% hydrogen peroxide) heat (60°C) and UV light (254 nm). The limit of detection and limit of quantification of Nateglinide, impurities A and B were found to be 0.05 and 0.15 μg /mL, respectively for 20 μL injection volume. The percentage recovery of Nateglinide was ranged from 98.4 to 100.9. The percentage recovery of impurities in Nateglinide sample was ranged from 96.8 to 103.5. The developed RP-HPLC method was validated with respect to linearity, accuracy, precision, robustness, and forced degradation studies prove the stability indicating power of the method.     

Effect of non-ionic surfactant concentration and type on the formation and stability of W/O/W multiple emulsions: Microscopic and conductometric evaluations

Abstract

W/O/W multiple emulsions with sodium salicylate as a model drug were prepared and evaluated for the effect of surfactant concentration and type on stability using microscopic and conductometric methods. Primary (W/O) emulsions were prepared with lipophilic surfactants (2-31% W/W relative to the oily phase). W/O/W emulsions were formed by mixing the primary emulsions with solutions containing 0.5 to 2% W/V hydrophilic surfactants. Optimum concentration of the lipophilic surfactant was 26% W/W. The optimum hydrophilic surfactant concentration was 1% W/V. Best stability was achieved with HLB 3.7 lipophilic and HLB 15.6 hydrophilic surfactants.     

Multielement analysis of polyethylene using solid sampling electrothermal vaporization ICP mass spectrometry

Next to laser ablation (LA) also electrothermal vaporization (ETV) from a graphite furnace as a means of sample introduction opens possibilities for direct analysis of solid samples using inductively coupled plasma mass spectrometry (ICPMS). In this paper, it is demonstrated that solid sampling ETV-ICPMS is very well suited for the determination of metal traces in polyethylene. A limited multielement capability is often cited as an important drawback of ETV-ICPMS. However, by studying the effect of monitoring an increasing number of mass-to-charge ratios on the signal profile (integrated signal intensity and repeatability) of selected analyte elements, the multielement capability of (solid sampling) ETV-ICPMS was systematically evaluated, and the results obtained suggest that, with a quadrupole-based ICPMS instrument, at least 11 elements can be determined "simultaneously" (from the same vaporization step), in essence without compromising the sensitivity or the precision of the results obtained. In this work, the "simultaneous" determination of Al, Ba, Cd, Cu, Mn, Pb, and Ti in a polyethylene candidate reference material has been accomplished, despite the large variation in analyte concentration (from 5 ng/g for Mn to 500 microg/g for Ti) and in furnace behavior (volatility) they exhibit. To avoid premature losses of Cd during thermal pretreatment of the samples, Pd was used as a chemical modifier. Two different calibration methods--external calibration using an aqueous standard solution and single standard addition--were studied and the results obtained were compared with those obtained using neutron activation analysis (NAA) and/or with the corresponding (candidate) certified values (if available). Single standard addition was shown to be preferable (average deviation between ICPMS result and reference value < 3%), although--except for Ba--acceptable results could also be obtained with external calibration.     

微波消解-电感耦合等离子体质谱法测定面制食品中铝的含量

本文以Li6为内标,采用微波消解-电感耦合等离子体质谱法(ICP—MS)对面制食品中铝的含量进行测定,通过对三种面制食品的加标回收试验,建立了面制食品中铝含量的ICP—MS分析方法,仪器检出限为在0.12ng/mL、测定的相对标准偏差均小于5.2%,加标回收率在90.4%97.6%。实验表明该法操作简单、快速,灵敏度高,重现性好,能够满足实际样品检测的要求。     

小麦粉及其制品中溴酸钾含量的测定

本方法采用离子色谱与电感耦合等离子体质谱联用技术(IC-ICP-MS)检测小麦粉及其制品中溴酸钾的含量。该方法利用离子色谱将溴酸根与溴离子等含溴化合物分离后在ICP-MS上通过质谱的高选择性检测而排除氯离子和有机酸等物质的干扰。该方法对溴酸钾的检测限可达0.02mg/kg。     

High-precision measurement of variations in calcium isotope ratios in urine by multiple collector inductively coupled plasma mass spectrometry

We describe a new chemical separation method to isolate Ca from other matrix elements in biological samples, developed with the long-term goal of making high-precision measurement of natural stable Ca isotope variations a clinically applicable tool to assess bone mineral balance. A new two-column procedure utilizing HBr achieves the purity required to accurately and precisely measure two Ca isotope ratios ((44)Ca/(42)Ca and (44)Ca/(43)Ca) on a Neptune multiple collector inductively coupled plasma mass spectrometer (MC-ICPMS) in urine. Purification requirements for Sr, Ti, and K (Ca/Sr > 10?000; Ca/Ti > 10?000?000; and Ca/K > 10) were determined by addition of these elements to Ca standards of known isotopic composition. Accuracy was determined by (1) comparing Ca isotope results for samples and standards to published data obtained using thermal ionization mass spectrometry (TIMS), (2) adding a Ca standard of known isotopic composition to a urine sample purified of Ca, and (3) analyzing mixtures of urine samples and standards in varying proportions. The accuracy and precision of δ(44/42)Ca measurements of purified samples containing 25 μg of Ca can be determined with typical errors less than ±0.2‰ (2σ).     

Feasibility study on the characterization of thin layers by charged-particle activation analysis

The purpose of this feasibility study was to investigate the possibilities and limitations of Charged-Particle Activation Analysis (CPAA) as a thin layer characterization method, i.e., the determination of the mass thickness or the composition of a thin layer. Therefore industrially important layers of sputtered Al, AlOx, TiQx (all three from the packaging industry), YBa2Cu3O6+delta, and Y2O3-stabilized ZrO2 (both superconducting industry) on different substrates were analyzed, and thereby the accuracy, the detection limits, and the precision of the method were studied. To test the accuracy, the same materials were also analyzed with neutron activation analysis (NAA) and inductively coupled plasma mass spectrometry (ICPMS). The results of CPAA compared with the results of NAA and ICPMS showed no significant difference at the 95% confidence level. The detection limits expressed as mass thickness were about 10-2 microg cm-2 or expressed as thickness 0.04 nm for a monatomic layer of Al. The experiments showed that the precision of the method depends only on the counting statistics. Generally we can conclude that CPAA is an absolute method for the characterization of "thin" layers, with respect to composition and mass thickness determinations.     

Silver halide sensitized gelatin holograms in Slavich PFG-01 red-sensitive emulsion

Abstract

Silver halide sensitized gelatin (SHSG) is an interesting technique for the production of holographic optical elements. It combines the high sensitivity of photographic emulsions with the well-known low scattering and high diffraction efficiency corresponding to dichromated gelatin. In this paper we describe SHSG holograms recorded on Slavich PFG-01 emulsions. We will show that real high diffraction efficiencies can be obtained (as high as 93% allowing for reflections) when using this material for recording phase transmission holograms. The influence of the bleach bath temperature and a hardening bath in the processing was studied and the procedure was optimized for these two parameters. Our investigations reveal that PFG-01 emulsion is not only a substitute for Agfa material, but also offers better results, at a moment in which Agfa has stopped its production of holographic material.     

A large bore-direct injection high efficiency nebulizer for inductively coupled plasma spectrometry

A large bore-direct injection high efficiency nebulizer (IB-DIHEN) is introduced that is less prone to capillary blockage and optimally operates at low nebulizer gas pressures compared with the conventional DIHEN used for inductively coupled plasma (ICP) spectrometries. The aerosol quality is examined using a two-dimensional phase Doppler particle analyzer (2D PDPA), and analytical figures of merits are acquired by ICP mass spectrometry. Compared with the DIHEN, the LB-DIHEN produces larger droplets, but the velocity distributions and mean droplet velocities are narrower and lower, respectively, providing longer residence times for the droplets in the plasma. High RF power (1500 W), low nebulizer gas flow rates (0.25-0.35 L/min), and low solution uptake rates (80-110 microL/min) are required to operate the LB-DIHEN at optimum conditions for ICPMS. Detection limits and sensitivities measured with the LB-DIHEN are superior to those of a conventional nebulizer-spray chamber combination, but precision is inferior. The performance of the LB-DIHEN is further explored in the determination of trace elements in an herbal extract.     

HR-ICP-MS测定电子级N-甲基吡咯烷酮中痕量金属杂质

文章采用高分辨电感耦合等离子体质谱仪(HR-ICP-MS)检测电子级N-甲基吡咯烷酮(NMP)中金属杂质元素,采用标准加入法进行定量测试,回收率为92.40%~110.25%,重复性相对标准偏差为0.19%~3.78%,检测限满足电子级NMP中金属杂质含量在0.1~1μg/kg级别测试需求。     

Measurement of Methionine and Methionine Sulphoxide in Photographic Gelatin using HPLC

Abstract

This report describes an improved method for the direct and simultaneous measurement of methionine and methionine sulphoxide in photographic gelatin using HPLC in the cationic exchange mode. While researchers have reported initial results using p-toluenesulphonic acid as the hydrolysing agent, this work shows significant improvements in both accuracy and precision using a melhane-sulphonic acid hydrolysis of gelatin. This report is a current assessment of this analytical method. Method evaluation including linearity, accuracy, and precision data are presented.     

Glow discharge source interfacing to mass analyzers: theoretical and practical considerations

The fundamental requirements for the optimum mechanical interface between a glow discharge ion source and a mass spectrometer are described in this paper. Specifically, the properties of a typical glow discharge ion source are compared and contrasted to those of a typical inductively coupled plasma ion source. The critical parameters and theoretical considerations of glow discharge and inductively coupled plasma ion source interfaces are reviewed, and the results of experiments using both quadrupole and time-of-flight mass spectrometers with a glow discharge source are presented. The experimental results clarify several important problems in the glow discharge ion sampling process. Our findings indicate that a shock wave structure does not occur in the supersonic expansion of the glow discharge ion source. Ions of different masses have similar initial kinetic energies in the glow discharge; thus, the angle of the skimmer cone is not a critical parameter for efficient ion beam extraction. Another consquence is that space charge effects in glow discharge ion sources repel heavy ions farther off axis than light ions. Thus, there are distinct and fundamental differences between glow discharge and inductively coupled plasma ion sources which are relevant to both ion sampling and ion extraction processes.