The task of the analytical chemist in industry

The duties of analytical chemists extend over a wide field, covering many branches of science, and in industry, too, a considerable part of the work consists of analytical determinations. The analytical chemist himself can do much to derive more satisfaction from his more or less subservient task and at the same time to meet more appreciation of his work.Analytical work in a large laboratory consists of: testing of materials and operating control analyses, analyses required for research work, standardisation of analytical methods and analytical research. Decentralisation of this work is often recommendable, especially as regards daily control analyses. However, there should be a central department which is thoroughly acquainted with all the analytical work in the whole laboratory, which sees to it that this work is done as efficiently as possible, which gives advice as to when and where existing methods are to be applied and which tests and developes new methods. Such an “analytical centre” is the source of analytical information for the whole staff.The large number of methods for the determination of the same magnitude and the many variations in procedure for one and the same method sometimes call for standardisation, to facilitate comparison of the results of various investigators.The analytical chemists in a laboratory should also be enabled to carry out analytical research work, so as to retain the necessary freshness and keep abreast of modern developments in their field.     

Assuring trueness of analytical results

Summary A true analytical result presumes an analytical procedure without systematic errors. They can be detected by comparing the analytical results with the true value or with an accepted reference. Systematic errors are always superimposed by the random error, therefore such a comparison must include statistical tests. The paper describes suitable test-models for typical analytical problems, as e.g. the validation of an analytical procedure or the (current) control of analytical work. Furthermore, explanations will be given for the interpretation of the test results due to the trueness of analytical data and for the consequences concerning analytical work.     

Quality assurance in the microbiology laboratory

 The pertinent issues necessary for the establishment of quality assurance in the microbiology laboratory are discussed. Quality assurance is a planned system of control measures that enables management to ensure that the analytical data produced in the laboratory are valid. To introduce quality assurance, all activities in the laboratory that affect the production of analytical data must be documented and controlled. These include sampling, method selection, laboratory environment, equipment, reagents and media, staff, reference materials and internal and external quality control. Laboratory accrediation in accordance with EN45001 and ISO Guide 25 enables laboratories demonstrate to an external agency their ability to perform analytical work and produce valid analytical data. This gives creditability to the laboratory and allows management to have confidence in the data produced. Received: 6 June 1995 Accepted: 3 July 1995     

Analytical process control of the Celeste R&D installation of IPEN-CNEN/SP

Celeste-1 is a lab-scale hot cell intended for R&D work in reprocessing of low burn-up spent fuel elements. The studies are concerned with head-end, first separation cycle by Purex Process using mini mixer-settlers and development of analytical techniques. The analytical monitoring for process control purposes is based on several off-line techniques, such as X-ray fluorescence spectrometry, potentiometric titration, -and -spectroscopy, spectrophotometry, fluorimetry, density measurement and gas chromatography. The analytical treatment takes place in a shielded working place analytical hot cell, glove boxes and hoods and some final measurements are made in the associated analytical laboratory. A pneumatic system is used for transporting analytical samples. All analytical procedures are ready and in operation.     

用平行双样测定结果相对偏差限值评估方法验证实验重复性限合理性的研究

分析方法标准验证实验得到的分析方法基本性能参数重复性限和再现性限是日常检测工作质控规范重要依据。以环境监测领域土壤、沉积物及固废样品中无机元素分析为例,考察了已颁布执行的标准文本和在生态环境部官网公开征求意见的分析方法标准中重复性限。将重复性限转化为相对偏差后,与日常检测工作中质控限值进行了比较。根据目前现行有效的平行双样测定结果相对偏差限值,方法验证数据有多大比例符合质控要求？根据方法验证结果,平行双样测定结果相对偏差限值有无改进可能？从上述两个角度进行了研究。研究结果表明：土壤、沉积物、固体废弃物中无机元素的测定,不同文献来源相同分析方法标准和不同分析方法标准,其重复性限转化得到的平行测定相对偏差合格率存在明显区别;用平行测定相对偏差限值可以快速判断标准文本中的重复性限是否合理,审核方法验证数据质量是否满足要求。基于已有标准文本方法验证数据,探讨了修改平行测定结果相对偏差限值可行性。     

On the role of characterization in the design of interfaces in nanoscale materials technology.

This work reviews recent research on the design and control of interfaces in engineering nanomaterials. Four case studies are presented that demonstrate the power of a multimodal approach to the characterization of different types of interfaces. We have used a combination of conventional, high resolution, and analytical transmission electron microscopy, microbeam electron diffraction, and three-dimensional atom probe to study polymer-clay nanocomposites, turbine rotor steels used for power generation, multicomponent aluminum alloys, and nanocrystalline magnetic materials.     

History of mass spectrometry at the Olympic Games

Mass spectrometry has played a decisive role in doping analysis and doping control in human sport for almost 40 years. The standard of qualitative and quantitative determinations in body fluids has always attracted maximum attention from scientists. With its unique sensitivity and selectivity properties, mass spectrometry provides state-of-the-art technology in analytical chemistry. Both anti-doping organizations and the athletes concerned expect the utmost endeavours to prevent false-positive and false-negative results of the analytical evidence. The Olympic Games play an important role in international sport today and are milestones for technical development in doping analysis. This review of the part played by mass spectrometry in doping control from Munich 1972 to Beijing 2008 Olympics gives an overview of how doping analysis has developed and where we are today. In recognizing the achievements made towards effective doping control, it is of the utmost importance to applaud the joint endeavours of the World Anti-Doping Agency, the International Olympic Committee, the international federations and national anti-doping agencies to combat doping. Advances against the misuse of prohibited substances and methods, which are performance-enhancing, dangerous to health and violate the spirit of sport, can be achieved only if all the stakeholders work together.     

Molecular Design of β‐Sheet Peptide for the Multi‐Modal Analysis of Disease

Intermolecular forces constrain peptide conformation. However, the role of each intermolecular force in constraining peptide conformation remains poorly understood. In this work, we show that aromatic–aromatic interactions drive peptides into β‐sheets, and the hydrophobic effect determines the assembly speed of peptides. By using intermolecular forces to artificially control the assembly of β‐sheets, a multi‐modal analytical system was developed that allows five readouts and dual qualitative–quantitative analysis, and satisfies both point‐of‐care testing (POCT) and laboratory‐based testing. For Mycoplasma Pneumoniae diagnosis, this system eradicates misdiagnosis (from 30 % to 0 %) and broadens the linear range by three‐fold, both of which are critical for guiding therapy. This work not only illustrates exact roles of intermolecular forces in driving the formation of β‐sheets, but also provides a guideline for the construction of a multi‐modal analytical system for disease diagnosis.     

On the analytical utility of quasi-linear molecular emission spectra

The analytical utility of the Shpol'skii effect has been examined. It is concluded that the combined instrumental and theoretical restrictions limit the analytical usefulness of true quasiline spectra for quantitative work.     

Analysis of food for toxic elements

The levels of the toxic elements Al, As, Cd, Hg, Pb and Sn are routinely monitored in food to protect the consumer. Increasingly, the chemical forms of As and Hg are also monitored. Analyses are performed to enforce regulatory standards and to accumulate background levels for assessing long-term exposure. The analytical procedures used for these activities evolve as requirements to determine lower levels arise and as both the types and sheer number of different foods that need to be analyzed increase. This review highlights recent work addressing improvements in the analysis of toxic elements in food. The topics covered include contamination control, analytical sample treatment and the common analytical techniques used for food analysis.     

Management of quality control in analytical laboratories

The sources of errors in the results of chemical analysis are classified. Methods for the on-line control of the precision and accuracy of analysis are briefly discussed and compared in order to reveal the types of sources of errors in the considered methods. Algorithms to estimate the quality of work of an analytical laboratory based on the statistical analysis of the summarized results of control obtained in a certain period of time are proposed.     

Analytical chemical laboratory exercises on basic and advanced level at the Technical University Budapest

An overview on the practical laboratory work done by the chemical engineering students is given at different levels of the curriculum of the Faculty of Chemical Engineering. Laboratory exercises and individual laboratory work is carried out at the following levels: Basic level. The different analytical chemical methods are acquisited by the students. Advanced level. A problem oriented project work is done with integrated use of the different analytical methods in the 8th semester. Thesis work. Specialized individual work on an elected research topic. Postgraduate courses. Organized for the understanding and practice of the latest methods and applications in the analytical chemistry. The programs of the different levels are detailed in the following. Received: 10 January 1996 / Accepted: 20 May 1996     

Performance tests and internal quality control activities for the routine analytical use of composite electrodes

The use of a solid electrode in routine analytical work is proposed as a good alternative for electroanalytical detection. The performance of the electrode for oxidative voltammetry was studied for the model compound, catechol. Some theoretical aspects of the preparation and features of the PVC-graphite composite electrode are shown. A protocol has been described for its construction and general advice for the appropriate use. Quality control activities were designed to check the performance of the electrode. Received: 7 October 2000 Accepted: 19 July 2001     

A new certified reference material for the quality control of palladium, platinum and rhodium in road dust, BCR-723

Certified Reference Materials (CRMs) represent a key tool for the quality control of chemical analyses. The demand for environmental materials is constantly increasing in complex analytical fields, and the European Commission (EC) (through the Measurements & Testing Generic Activity) is responding to the urgent needs for materials requiring collaborative efforts at the international level. This paper describes the preparation of a new road-dust material (BCR-723), along with homogeneity and stability studies and the analytical work performed for the certification of the contents of palladium, platinum and rhodium, under the EC's PACEPAC project, PACEPAC being the acronym for “Production And CErtification of a road dust reference material for Platinum, palladium and rhodium used in Automotive Catalytic converters”.     

A facility for multielemental analysis by PIXE and the19F(p, αγ)16O reaction

Specific advantages with Particle Induced X-Ray Emission are: its (1) multielemental capability, especially when combined with nuclear techniques for lighter elements, (2) speed, (3) low detection limits for small samples and (4) accuracy. To make full use of these advantages, analytical parameters have to be chosen optimally and the facility to be carefully designed. This paper describes an experimental facility constructed to permit continuous development work to optimize the analytical conditions and to allow the gradual implementation of automatic control. Emphasis is also put on the simultaneous use of proton induced gamma rays from fluorine. The features and the performance of the set-up including its accuracy, precision and experimental detection limits are reported.     

Certification of reference materials for the quality control of major element determinations in groundwater Part 2: Certification

The quality control of groundwater monitoring requires the availability of representative CRMs. This paper describes the preparation of two artificial groundwater reference materials, CRM 616 (high carbonate content) and CRM 617 (low carbonate content), the homogeneity and stability studies and the analytical work performed for the certification of a range of major elements (Ca, Cl, Fe, K, Mg, Mn, Na, NO₃, PO₄ and SO₄).     

A fully automated mass spectrometer for the analysis of organic solids

Automation of a mass spectrometer—computer system makes it possible to process up to 30 samples without attention after sample loading. An automatic sample changer introduces the samples successively into the ion source by means of a direct inlet probe. A process control unit determines the operation sequence. Computer programs are available for the hardware support, system supervision and evaluation of the spectrometer signals. The most essential precondition for automation — automatic evaporation of the sample material by electronic control of the total ion current — is confirmed to be satisfactory. The system operates routinely overnight in an industrial laboratory, so that day work can be devoted to difficult analytical problems. The cost of routine analyses is halved.     

Analytical approach on surface active agents in the environment and challenges

Surface active agents (SAAs) are a class of compounds, which is used in variety of products such as detergents, fabric softeners, soaps, paints, adhesives, inks and anti-fogs. After the use of these products containing surfactants are disposed in water reservoirs. The separation and determination of surfactants from complex matrices become challenging for analytical chemists. The fundamentals on separation, preconcentration and analysis of surfactants employing different analytical instrumental techniques for qualitative and quantitative determination of surfactants in environmental samples are discussed. In addition, this compiled work enhanced our knowledge in learning about pathway mechanisms and the degree of their environmental loads. We also discussed the different aspects of method validation in the framework of quality control (QC) and quality assurance (QA). This review provides information on levels of SAAs in various environmental samples including soil, sediments, sewage wastewater, river wastewater and aerosols worldwide.     

Electrochemical detection of tobramycin or gentamicin according to the European Pharmacopoeia analytical method

Tobramycin and gentamicin are two aminoglycosidic antibiotics used in lung infection, ophthalmic treatments as well as in skin infections. Pharmaceutical companies which produce remedies containing tobramycin and gentamicin need an analytical method for their internal quality control. For several years a simple chromatographic method based on anion exchange separation coupled with amperometric detection was proposed for aminoglycosides. This analytical approach was partially used in the last edition of the European Pharmacopoeia (EP) for tobramycin and gentamicin analysis. In fact they use integrated pulsed amperometric detection (IPAD) on a gold electrode while the separation is obtained on a polymeric wide pore reversed phase instead of anion exchange in alkaline conditions. Such coupling seems to be cumbersome and not so easy to realize and to reproduce from one laboratory to another. Besides, the described method lacks some of the details as important as the waveform steps duration. Unfortunately the quality control (QC) laboratories have to use exactly the method described in the EP, so they complained about the troubles. Therefore, the EP authors published recently a paper regarding the guidelines for good practice in the method application, but the suggestion was not yet resolutive. In our work we evaluated the eluent composition and the kind of amperometric cell, work electrode diameter and cell volume. Mainly we optimized the amperometric waveform. In addition, for tobramycin analysis another chromatographic phase was explored in order to achieve better efficiency and to separate all the impurities confirming the effectiveness of the detection. The conditions described in the paper seem to allow the analyst to operate in conformity with the EP method.     

Analytical approaches to expanding the use of capillary electrophoresis in routine food analysis

Capillary Electrophoresis (CE) is becoming an ever more powerful analytical technique for the separation, identification, and quantification of a wide variety of compounds of interest in many application fields. Particularly in food analysis this technique can offer interesting advantages over chromatographic techniques because of its greater simplicity and efficiency. Nevertheless, CE needs to advance with regard to compatibility with sample matrices, sensitivity, and robustness of the methodologies in order to gain even wider acceptance in food analysis laboratories, specially for routine work. This article presents various approaches to expanding the analytical usefulness of CE in food analysis, discussing their advantages over conventional CE. These approaches focus on sample screening, automated sample preparation with on-line CE arrangements, and the automatic integration of calibration in routine analytical work with CE.