Qualitative and Quantitative Detection of Botulinum Neurotoxins from Complex Matrices: Results of the First International Proficiency Test

In the framework of the EU project EQuATox a first international proficiency test (PT) on the detection and quantification of BoNT was conducted. Sample materials included BoNT serotypes A, B and E spiked into buffer, milk, meat extract and serum. A variety of methods was applied by the participants combining different principles of detection, identification and quantification. Based on qualitative assays, 95% of all results reported were correct. Successful strategies for BoNT detection were based on a combination of complementary immunological, MS-based and functional methods or on suitable functional in vivo / in vitro approaches (mouse bioassay, hemidiaphrama assay, Endopep-MS assay). Quantification of BoNT/A, BoNT/B and BoNT/E was performed by 48% of participating laboratories. It turned out that precise quantification of BoNT was difficult resulting in a substantial scatter of quantitative data. This was especially true for results obtained by the mouse bioassay which is currently seen as “gold standard” for BoNT detection. The results clearly demonstrate the urgent need of certified BoNT reference materials and the development of methods replacing animal testing. In this context, the BoNT PT provided the valuable information that both the Endopep-MS assay and the hemidiaphrama assay delivered quantitative results superior to the mouse bioassay.JRC.D.2-Standards for Innovation and sustainable Developmen

Report of the panel on geopotential fields: Gravity field, section 8

The objective of the Geopotential Panel was to develop a program of data acquisition and model development for the Earth's gravity and magnetic fields that meet the basic science requirements of the solid Earth and ocean studies. Presented here are the requirements for gravity information and models through the end of the century, the present status of our knowledge, data acquisition techniques, and an outline of a program to meet the requirements

Challenges in the Development of Reference Materials for Protein Toxins

High molecular weight protein toxins produced by bacteria, e.g. staphylococcal enterotoxins and botulinum neurotoxins, as well as plant toxins such as ricin and abrin, are relevant analytes in different application areas: food safety, public health, civil security and defense sector, and – in case of botulinum neurotoxins – also in pharmaceutics. For their reliable and accurate detection, identification and quantification, reference materials (RMs), in particular certified reference material (CRM), are required. The present article focuses on challenges in the development (production and certification) of such RMs. Firstly, it highlights the role of RMs and CRMs, what they can be used for, the nature of certified properties, metrological traceability, and uncertainty of certified values, as well as commutability of RMs. Secondly, the molecule-specific technical challenges are highlighted using the example of the mentioned toxins. This includes for instance the choice of a suitable purification strategy (recombinant expression and purification versus the purification of toxin from natural sources), the in-depth characterization of the obtained preparations by a comprehensive set of methods including immunochemical assays, mass spectrometry, and functional assays to verify their identity and establish their purity and activity, and finally, suitable approaches for determining reference values of important toxin properties (protein mass concentration in solution, biological activity). The article summarizes ongoing activities in a new European initiative called EuroBioTox, which aims at the production and certification of RMs for selected protein toxins and the establishment of validated procedures for the detection and identification of biological toxins

Qualitative and Quantitative Detection of Botulinum Neurotoxins from Complex Matrices: Results of the First International Proficiency Test

In the framework of the EU project EQuATox, a first international proficiency test (PT) on the detection and quantification of botulinum neurotoxins (BoNT) was conducted. Sample materials included BoNT serotypes A, B and E spiked into buffer, milk, meat extract and serum. Different methods were applied by the participants combining different principles of detection, identification and quantification. Based on qualitative assays, 95% of all results reported were correct. Successful strategies for BoNT detection were based on a combination of complementary immunological, MS-based and functional methods or on suitable functional in vivo/in vitro approaches (mouse bioassay, hemidiaphragm assay and Endopep-MS assay). Quantification of BoNT/A, BoNT/B and BoNT/E was performed by 48% of participating laboratories. It turned out that precise quantification of BoNT was difficult, resulting in a substantial scatter of quantitative data. This was especially true for results obtained by the mouse bioassay which is currently considered as “gold standard” for BoNT detection. The results clearly demonstrate the urgent need for certified BoNT reference materials and the development of methods replacing animal testing. In this context, the BoNT PT provided the valuable information that both the Endopep-MS assay and the hemidiaphragm assay delivered quantitative results superior to the mouse bioassay

Cost management systems: an example of how to implement activity accounting, Siemens AG, West Germany

SIGLEAvailable from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel C 173289 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman