TY - JOUR A1 - Molloy, J. L. A1 - Winchester, M. R. A1 - Butler, T. A. A1 - Possolo, A. M. A1 - Rienitz, O. A1 - Roethke, A. A1 - Goerlitz, V. A1 - Caciano de Sena, R. A1 - Dominguez Almeida, M. A1 - Yang, L. A1 - Methven, B. A1 - Nadeau, K. A1 - Romero Arancibia, P. A1 - Bing, W. A1 - Tao, Z. A1 - Snell, J. A1 - Vogl, Jochen A1 - Koenig, Maren A1 - Kotnala, R. K. A1 - Swarupa Tripathy, S. A1 - Elishian, C. A1 - Ketrin, R. A1 - Suzuki, T. A1 - Oduor Okumu, T. A1 - Yim, Y.-H. A1 - Heo, S. W. A1 - Min, H. S. A1 - Sub Han, M. A1 - Lim, Y. A1 - Velina Lara Manzano, J. A1 - Segoviano Regalado, F. A1 - Arvizu Torres, M. A1 - Valle Moya, E. A1 - Buzoianu, M. A1 - Sobina, A. A1 - Zyskin, V. A1 - Sobina, E. A1 - Migal, P. A1 - Linsky, M. A1 - Can, S. Z. A1 - Ari, B. A1 - Goenaga Infante, H. T1 - CCQM-K143 Comparison of Copper Calibration Solutions Prepared by NMIs/DIs N2 - CCQM-K143 is a key comparison that assesses participants’ ability to prepare single element calibration solutions. Preparing calibration solutions properly is the cornerstone of establishing a traceability link to the International System of Units (SI), and therefore should be tested in order to confirm the validity of CCQM comparisons of more complex materials. CCQM-K143 consisted of participants each preparing a single copper calibration solution at 10 g/kg copper mass fraction and shipping 10 bottled aliquots of that solution to the coordinating laboratory, the National Institute of Standards and Technology (NIST). The masses and mass fraction for the prepared solutions were documented with the submitted samples. The solutions prepared by all participants were measured at NIST by high performance inductively coupled plasma optical emission spectroscopy (HP-ICP-OES). The intensity measurements for copper were not mapped onto values of mass fraction via calibration. Instead, ratios were computed between the measurements for copper and simultaneous measurements for manganese, the internal standard, and all subsequent data reductions, including the computation of the KCRV and the degrees of equivalence, were based on these ratios. Other than for two participants whose measurement results appeared to suffer from calculation or preparation errors, all unilateral degrees of equivalence showed that the measured values did not differ significantly from the KCRV. These results were confirmed by a second set of ICP-OES measurements performed by the Physikalisch-Technische Bundesanstalt (PTB). CCQM-K143 showed that participants are capable of preparing calibration solutions starting from high purity, assayed copper metal. Similar steps are involved when preparing solutions for other elements, so it seems safe to infer that similar capabilities should prevail when preparing many different, single-element solutions. KW - Metrology KW - Primary calibration solution KW - Traceability PY - 2020 DO - https://doi.org/10.1088/0026-1394/58/1A/08006 SN - 0026-1394 VL - 58 IS - 1A SP - 08006 PB - IOP Science CY - Cambridge AN - OPUS4-51983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Silke A1 - Roethke, A. A1 - Rienitz, O. A1 - Matschat, Ralf A1 - Schiel, D. A1 - Jaehrling, R. A1 - Goerlitz, V. A1 - Kipphardt, Heinrich T1 - SI-traceable monoelemental solutions on the highest level of accuracy: 25 years from the foundation of CCQM to recent advances in the development of measurement methods N2 - Within the Working Group on Inorganic Analysis (IAWG) of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM) international key comparisons and pilot studies related to inorganic analysis are carried to ensure consistency in this field at the highest level. Some of these comparisons deal directly with the preparation and characterization of monoelemental solutions or with topics, closely related. The importance of monoelemental solutions lies in the fact that almost every measurement in inorganic analysis relies on the comparison with either a reference material, or references in form of solutions, usually (mono)elemental solutions. All quantitative measurement approaches, e.g. isotope dilution or standard addition, need an accurate reference solution made from a well characterized reference material, prepared under full gravimetric control. These primary (monoelemental) solutions do not only serve as arbitrary references/calibration solutions, but they also link up measurement results to the International System of units (SI), this way establishing the so-called metrological traceability to a measurement unit of the SI. Without such solutions on the highest possible level of accuracy and with the smallest possible associated uncertainties (for e.g. element content and/or impurities), an analysis itself can never be as good as it could be with appropriate reference solutions. This article highlights select key comparisons and pilot studies dealing with monoelemental solution related topics within the IAWG from the foundation of CCQM – 25 years ago – up to latest achievements in the field of inorganic analysis. KW - Metrology KW - SI Traceability KW - CCQM PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-496080 DO - https://doi.org/10.1088/1681-7575/ab5636 SN - 0026-1394 SN - 1681-7575 SP - 1 EP - 23 PB - IOP CY - Bristol AN - OPUS4-49608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Roethke, A. T1 - SI-traceable monoelemental solutions on the highest level of accuracy: From the foundation of CCQM to recent advances N2 - Shortly after founding the CCQM in 1993, the first key comparison (CCQM-K2) about the determination of Cd and Pb content in river water was hosted by IRMM. It has been clear from the beginning that for the determination of an element mass fraction in a matrix, accurate reference solutions would be the key point for a metrologically sound analysis. Triggered by the not entirely satisfactory results it was decided to investigate the basis of all measurements: the reference solutions. Thus in 1999, CCQM-K8, hosted by EMPA/LNE, started the tedious but indispensable work on elemental solutions standards. Additionally, PTB, BAM and Merck KGaA initiated a project to establish a traceability system for inorganic analysis based on accurate monoelemental solutions. Within this unique approach ten high purity reference materials were fully characterized, and solutions were prepared gravimetrically thereof. These materials (forming the primary standards of elemental analysis) are available for NMIs/DIs from BAM. CCQM-P46 (Cu, Mg, Rh) demonstrated the actuality of the topic and the challenges to prepare elemental solutions for every element. The accurate preparation and use of monoelemental solutions is consequently reflected in the recurrent conduct of (key) comparisons: CCQM-P149 (purity of zinc), CCQM-K87 (Co, Cr, Pb), and the current CCQM-K143/P181 (Cu solutions), to name only a few in a long series. Is it necessary to put so much effort into the preparation of reference solutions? It clearly is! An example outside the world of academia: Recently, EDQM*, PTB, BAM and JRC have developed monoelemental reference standards traceable to the SI for toxic elements in support of the chapters of the European Pharmacopoeia, related to the analysis of elemental impurities in medicinal products. A new ICP OES method has been established allowing the comparison of two 1 g/kg mercury solutions with an outstandingly small uncertainty of Urel(w(Hg)) = 0.16 %. However, this technical progress would not have been possible without the ongoing effort of the metrological community within 25 years of research in the field of high accuracy monoelemental solutions. * EDQM: European Directorate for the Quality of Medicines and HealthCare T2 - CCQM Workshop on Advances in Metrology in Chemistry and Biology CY - Sevre DA - 10.04.2019 KW - CCQM KW - SI-traceable KW - Monoelemental solutions PY - 2019 UR - https://youtu.be/iVLk8CFnJTI AN - OPUS4-47846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -