International Atomic Energy Agency's contributions to advances in nutritional and environmental metrology

For more than three decades the International Atomic Energy Agency (IAEA) has supported projects on food, nutrition and environment for strengthening the analytical capabilities in developing countries (DCs). Over time, such efforts have led to the development of proper study designs, harmonization of sampling protocols, adequate contamination control and evaluation of the suitability of competing analytical techniques for the determination of specific analytes. Collectively, these consistent IAEA initiatives have promoted harmonization of chemical measurements thus facilitating comparability of results of filed investigations. Importantly, the Agency's efforts have infused a measure of metrological awareness in measurements carried out in field studies, including physiological measurements. Nuclear and isotopic techniques have played an important role in reaching these goals by establishing reliable measurement processes for application in health care studies.     

The role of analytical chemistry in process quality control

The growing need for quality supervision and control in production processes is briefly outlined. After a summary of available process analytical devices, and a short discussion of their possibilities and limitations, an alternative approach is discussed. This approach is based on the development of a dynamic process model which allows on-line quality predictions to be made by means of so- called state estimators. The advantage is that it becomes possible to use quantities which give only indirect information about the product quality, but which are more readily accessible for continuous or on-line monitoring in earlier stages of the process.     

The experience of accreditation of an analytical laboratory at the Argentine Atomic Energy Commission

The implementation of a quality system based on the ISO/IEC 17025:1999 standard is a growing necessity for analytical laboratories to demonstrate their technical competence. In 2001, the Nuclear Analytical Techniques Group of the Argentine Atomic Energy Commission obtained the recognition of the International Atomic Energy Agency in the application of neutron activation analysis and the accreditation by the national accreditation body. The importance of the participation of the group in the Agency's Regional Programme for Latin America, ARCAL XXVI on Quality Assurance in Analytical laboratories is discussed, as well as the activities performed to attain these objectives. Some improvements worth mentioning resulted from the implementation of the quality system and, following the premise of continuous improvement, changes were introduced aiming at the laboratory re-accreditation.     

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.     

ROSA analytical center for water quality control

This paper describes the range of analytical problems to be solved, the equipment, structure, and personnel structure of the center, the methods for ensuring the quality of analyses, and the external relations.     

Nuclear analytical methods in quality control of microanalysis

Quantitative calibration and quality control have been a major bottleneck in microanalysis due to the lack of natural-matrix CRMs certified at sample sizes compatible with those of unknown samples. In this paper, a solution is described to characterize sampling behavior for individual elements, so as to identify elements homogeneous enough at stated sample size levels in given CRMs/RMs. By using a combination of several nuclear analytical techniques, INAA-EDXRF-μPIXE, sampling behavior for individual elements can be characterized at sample size levels from grams down to pg. Natural-matrix CRMs specifically for QC of microanalysis may thus be created. Additional information in certificates of these new generation CRMs is imagined. This revised version was published online in July 2006 with corrections to the Cover Date.     

Standardization, quality control and education in analytical chemistry

Quality matters have always been an intrinsic component of any curriculum in analytical chemistry. The realizations in the past have shown a wide variability in different countries. With the on-going internationalization of trade this is not a satisfactory situation as the goal of a measurement science supporting this globalization must encompass compatible measurement systems. In order to meet these requirements as soon as possible, and not just with future generations of yet-to-be-trained college graduates, a vigorous program of postgraduate education in analytical quality assurance is necessary in all countries, many of which have already recognized this need and introduced special courses dealing with these topics.This contribution presents a compilation of the most important current developments in analytical quality assurance as these also define the most urgent needs to reshape the educational process for graduates and post-graduates alike. Quantitative concepts are emphasized and the correlations between them are highlighted. Suggestions for topics to be covered in a 4-day post-graduate course on analytical quality assurance are given, based on more than five years of experience.Dedicated to my mother, Dr. med. univ. Gerda Wegscheider, on the occasion of her 70th birthday     

Green analytical chemistry: Opportunities for pharmaceutical quality control

This review article summarizes the opportunities for utilizing the green analytical chemistry (GAC) techniques and principles in the field of quality control (QC) of pharmaceuticals. Green analytical chemistry is considered a branch of the green chemistry based on the principles overlapping with the goals of sustainable development. General definitions of quality and quality control, the principles of GAC, proposals for greener sample pretreatment and greener chromatographic method of analysis applied in QC laboratories are discussed herein. The main goal is to achieve more eco-friendly analysis in QC laboratories through different strategies and techniques, replace toxic reagents, and modify or replace analytical methods and/or techniques with safer ones, making it possible to dramatically reduce the amounts of reagents consumed and waste generated.     

Comparison of three analytical methods for quality control of clozapine tablets

Three different analytical methods for the quality control of clozapine in commercial formulations were developed and compared: a liquid chromatographic (LC) method with UV detection, a capillary zone electrophoretic (CZE) method, and a linear scan voltammetric (LSV) method. The isocratic LC procedure used a C18 reversed-phase column; the CZE method used an uncoated fused-silica capillary and phosphate buffer containing polyvinylpyrrolidone as the background electrolyte; the LSV method analyzed clozapine solutions with acidic phosphate buffer as the supporting electrolyte. The 3 methods gave similar and satisfactory results, in terms of precision and accuracy. Repeatability and intermediate precision were good (RSD% < 2.2) and accuracy, resulting from recovery studies, was between 98 and 102%. The rapidity of analysis was high for all 3 methods, especially for the LSV.     

Certification of two human hair reference materials issued by the International Atomic Energy Agency

Two new human hair reference materials, with different levels of mercury and methylmercury, have been developed and characterized by the International Atomic Energy Agency, for use in validation of measurements for mercury exposure. The set of materials consists of IAEA-086, with a low level of methylmercury, and IAEA-085, with an elevated methylmercury level. An international intercomparison exercise was carried out, and 68 institutes from 40 countries have contributed data. Based on the evaluation of the results from the intercomparison and analyses by expert laboratories, values of 23.2 and 0.57 mg/kg total mercury are recommended for IAEA-085 and IAEA-086, respectively. Values for methylmercury are recommended at 22.9 mg/kg, MeHg as Hg, for IAEA-085, and at 0.26 mg/kg, MeHg as Hg, for IAEA-086. Recommended and information values are also given for other selected trace elements.     

Comparison of analytical methods for quality control of pharmaceutical formulations containing glutathione

Summary The aim of this investigation was the study and development of analytical procedures suitable for the assay of glutathione (GSH) in pharmaceutical formulations. Two are based on isocratic HPLC with a 250 mm×4.6 mm i.d., 5 μm C₁₈ column and UV detection. In the first procedure sample solutions were injected without pretreatment whereas in the second the samples were injected after derivatization with Ellman’s reagent which forms an easily detectable adduct with GSH. Good linearity was obtained over the range 0.12–6.00×10⁻⁴M for the direct procedure and 0.25–3.00×10⁻⁴M for the derivatization procedure. The precision and rapidity of analysis were also good for both methods. The third method is based on capillary zone electrophoresis (CZE) in a 27 cm×75 μm i.d untreated fused silica capillary containing pH 7 phosphate buffer. All results are in good agreement with a spectrophotometric procedure used as reference method.     

The NIH analytical methods and reference materials program for dietary supplements

Quality of botanical products is a great uncertainty that consumers, clinicians, regulators, and researchers face. Definitions of quality abound, and include specifications for sanitation, adventitious agents (pesticides, metals, weeds), and content of natural chemicals. Because dietary supplements (DS) are often complex mixtures, they pose analytical challenges and method validation may be difficult. In response to product quality concerns and the need for validated and publicly available methods for DS analysis, the US Congress directed the Office of Dietary Supplements (ODS) at the National Institutes of Health (NIH) to accelerate an ongoing methods validation process, and the Dietary Supplements Methods and Reference Materials Program was created. The program was constructed from stakeholder input and incorporates several federal procurement and granting mechanisms in a coordinated and interlocking framework. The framework facilitates validation of analytical methods, analytical standards, and reference materials.     

Recent analytical approaches in quality control of traditional Chinese medicines—A review

Traditional Chinese medicines (TCMs) are gaining more and more attention all over the world, due to their specific theory and long historical clinical practice. But the uncontrollable quality is a bottleneck for its modernization and globalization. This paper reviewed the recent analytical methods in the quality control of TCMs, including screening strategies of bioactive markers from TCMs through biochromatographic methods, the traditional chromatographic methods, DNA methods, as well as the spectroscopic methods, including FT-IR, NIR and NMR. The comprehensive methods, such as fingerprint and multi-component quantification are emphasized; hyphenated techniques, like HPLC-MS, GC-MS, CE-MS, LC-NMR, chemometric methods, and combination of chemical and biological methods, such as biofingerprint, metabolic fingerprint are now more and more widely used in TCMs. In a few word, the analysis and quality control of TCMs are moving towards an integrative and comprehensive direction, in order to better address the inherent holistic nature of TCMs.