How IAF and ILAC manage the recognition of Regional Accreditation Groups: the peer evaluation system of IAF and ILAC for Regional Accreditation Groups

The peer evaluation of single accreditation bodies in order to sign an Arrangement for Recognition of the international accreditation organizations International Accreditation Forum, Inc. (IAF) and International Laboratory Accreditation Cooperation (ILAC), whether performed by Regional Accreditation Groups or directly by IAF and/or ILAC, is standard practice. The fundamental requirements for such evaluations are well specified in documents. However, the careful evaluation of all their Arrangement members poses an enormous logistic task for IAF and ILAC, and the signatories can be evaluated more thoroughly within their Regional Groups. Hence, IAF and ILAC typically evaluate only the Regional Accreditation Groups and accept all signatories of a Regional Accreditation Group once successfully evaluated by their respective Regional Group. However, the requirements for the evaluation of a Regional Group are extensive, and the evaluation procedure is highly complicated and must be conducted very carefully in order to assure that the results of accreditation can be trusted. This article describes the evaluation procedure used by IAF and/or ILAC for Regional Groups wishing to sign the IAF/ILAC Arrangement. We wish to inform and to aid these Regional Groups setting out for evaluation, and also to build confidence in the IAF/ILAC Arrangements.     

Implementation of ISO/IEC 17025 Standard for the accreditation of analytical laboratories in Russia

The history since 1992 and the current state of affairs of the Russian Accreditation system for analytical laboratories are described. Some national characteristics of the implementation of the ISO/IEC 17025 Standard in Russia are considered. The elucidation of some ISO/IEC 17025 Standard prepositions is presented to facilitate implementation of the Standard by accreditation bodies and analytical laboratories claiming accreditation.     

The Japan Accreditation Board for Conformity Assessment – Introduction to the Japanese accreditation system

 The background to the establishment of the Japan Accreditation Board for Conformity Assessment (JAB) is reviewed in relation to the latest global developments in conformity assessment activities. JAB (known as the Japan Accreditation Board for Quality System Registration at the time of its establishment) was established in 1993 as the accreditation body for quality system registration, the focal point for conformity assessment in the private sector in Japan. The extension of the area of accreditation was made in June 1996, covering all conformity assessment activities including laboratory accreditation, which resulted in the amendment of the name of the body to the current one. Various elements of the laboratory accreditation program are introduced to give the overview of this new program. Received: 2 October 1996 Accepted: 5 December 1996     

Flexibilization of the scope of accreditation: an important asset for food and water microbiology laboratories

Beltest, the Belgian accreditation body, has investigated flexibilization of the scope of accreditation for chemistry laboratories and food and water microbiology laboratories. This flexibilization, synonymous with test-type accreditation, allows a laboratory to add new test methods or retry previous test methods without having to undergo a new audit by Beltest. It has been used for nearly ten years by German and Swiss accreditation bodies. Flexibilization permits the validation of methods and results, given that the competence of the particular laboratory is already well established. This new concept in microbiology allows client’s needs to be adequately met, and facilitates the quick establishment of a method in several laboratories at once in case of a public health crisis. The first laboratory to participate at this investigation on the flexibilization concept, as a test of the concept, was the Belgian reference laboratory for food microbiology.     

Certification of reference materials and accreditation of reference material producers: Questionable terminology leads to confusion

In the view of the Deutscher Kalibrierdienst (DKD) , a certifying body for reference materials can be considered to be a calibration laboratory. Therefore, accreditation of calibration laboratories in accordance with ISO/IEC 17025 is the most appropriate way to establish confidence in certificates for reference materials. If necessary, the criteria of ISO/IEC 17025 can be tailored to specific cases. There is no need to provide any new kind of reference-material specific accreditation. However, in view of the variety of reference materials and the practice existing in other countries, accreditation of testing laboratories and product certification bodies may optionally be acceptable as long as the same stringent principles with respect to traceability and measurement uncertainty are applied. Such accreditations but not accreditations of reference material producers (ISO Guide 34) are also covered by existing international mutual recognition arrangements (MRA).     

A combination of accreditation and certification in an evolving process at EMPA: A management system to meet ISO 9001, ISO 14001 and EN 45001

 The Swiss Federal Laboratories for Materials Testing and Research (EMPA) have established a quality assurance system based on EN 45001 which meets the requirements for accreditation of all EMPA's testing activities. As testing is only a part of EMPA's range of activities, and is performed in decentralised departments, the system does not satisfy the management needs. The fundamental reorganisation of EMPA's St. Gallen site was used as an opportunity to implement an overall process-oriented management system which also included quality and the needs for accreditation. Later, an environmental management system was added and then certified for ISO 9001 and 14001. The system consists of a "Management Manual" for the St. Gallen site and a customised "Quality Manual" for each department. One of the key elements is a comprehensive review and planning procedure covering all business aspects.     

Dynamic NMR: A single operational parameter approach for evaluation of lifetime in an uncoupled,equally populated AB system

Two simple formulae involving only one variable are presented for the simple and rapid estimation of the mean lifetime (τ) of exchange in uncoupled, paripartite AB systems. These formulae are shown to provide τ values comparable to those obtained from total line-shape analysis.     

新型芯片电泳柱端安培检测系统的构建与评价

自行设计开发了一套便于与电泳芯片集成的一体式柱端安培检测池系统．该系统由整块透明有机玻璃精密加工而成,包括电泳芯片支架和安培检测池两部分,芯片可通过芯片插槽和不锈钢夹具固定在芯片支架上,各种检测用电极可直接通过螺母固定在安培检测池中．以100μmol／L的DA为模式分析物,分别采用直径为100、300和500μm的铂金圆盘电极与表观直径为240μm的碳纤维电极作为工作电极均在该装置上实现了良好组装和高灵敏检测．采用碳纤维工作电极对该系统的检测参数进行了优化．测试结果表明该系统在电化学清洗程序下连续六次测定100μmol／L多巴胺的峰电流相对标准偏差为3．2％,保留时间相对标准偏差为0．5％,DA的检测限为0．4μmol／L（按照S／N=3计）．该系统体积小巧,测试稳定,检测灵敏度较高,工作电极更换方便,适合作为芯片电泳柱端安培检测通用平台．     

Construction and evaluation of a novel end-column amperometric detection system for electrophoresis microchips

A set of integrated end-column amperometric detection system has been developed,onto which an electrophoresis microchip can be conveniently integrated.Finely machined by a piece of transparent organic glass,the system consists of an electrophoresis microchip platform and an amperometric detection reservoir,in which the microchip can be fixed onto the platform by microchip grooves and with stainless steel fixture.Each detection electrode can be directly fixed in the amperometric detection reservoir by screws...     

Development and accreditation to ISO/IEC 17025 calibration status of a melting point measurement facility for the UK

A melting point measurement facility for the UK has been developed and accredited to ISO/IEC 17025 Calibration status for the determination of the liquefaction temperature of pure substances from 35 to 250°C. The facility is based upon a commercial instrument, i.e. an oil bath fitted with an aluminium block (Isotech, model 798 EHT), a precision multimeter (Isotech TTI-7), a thermocouple directly inserted in the sample under investigation and a platinum resistance thermometer (PRT) tracking the block temperature. The homogeneity of temperature bath/block was investigated and the PRT used for the traceability of the measurements was calibrated by NPL and traceable to ITS-90. The process was validated using four current LGC Certified Reference Materials (CRMs):

C-H amination in synthesis: an approach to the assembly of the B/C/D ring system of aconitine

A strategy for the preparation of aconitine is described that attempts to exploit chemoselective C-H amination and the electrophilic reactivity of oxathiazinane N,O-acetals for assembling the complex, polycyclic carbon framework of the natural product.     

Synthetic approach to grayanotoxins: a new method for the construction of the a-homograyanotoxane ring system

The A-homograyanotoxane ring system was constructed by a thermolysis of benzocyclobutene, followed by a Wagner-Meerwein rearrangement of the resulting kaurane type of compound.     

Simple and exact approach to the electronic polarization effect on the solvation free energy: formulation for quantum-mechanical/molecular-mechanical system and its applications to aqueous solutions

We present a simple and exact numerical approach to compute the free energy contribution δμ in solvation due to the electron density polarization and fluctuation of a quantum-mechanical solute in the quantum-mechanical/molecular-mechanical (QM/MM) simulation combined with the theory of the energy representation (QM/MM-ER). Since the electron density fluctuation is responsible for the many-body QM-MM interactions, the standard version of the energy representation method cannot be applied directly. Instead of decomposing the QM-MM polarization energy into the pairwise additive and non-additive contributions, we take sum of the polarization energies in the QM-MM interaction and adopt it as a new energy coordinate for the method of energy representation. Then, it is demonstrated that the free energy δμ can be exactly formulated in terms of the energy distribution functions for the solution and reference systems with respect to this energy coordinate. The benchmark tests were performed to examine the numerical efficiency of the method with respect to the changes in the individual properties of the solvent and the solute. Explicitly, we computed the solvation free energy of a QM water molecule in ambient and supercritical water, and also the free-energy change associated with the isomerization reaction of glycine from neutral to zwitterionic structure in aqueous solution. In all the systems examined, it was demonstrated that the computed free energy δμ agrees with the experimental value, irrespective of the choice of the reference electron density of the QM solute. The present method was also applied to a prototype reaction of adenosine 5'-triphosphate hydrolysis where the effect of the electron density fluctuation is substantial due to the excess charge. It was demonstrated that the experimental free energy of the reaction has been accurately reproduced with the present approach.     

A novel approach for monitoring of cyanobacterial toxins: development and evaluation of the passive sampler for microcystins

We have investigated the ability of an integrative sampler for polar organic chemicals to sequestrate a group of common and highly hazardous cyanobacterial toxins—microcystins. In a pilot experiment, commercially available passive samplers were shown to effectively accumulate microcystins after 7 days’ exposure in the field. To find the most efficient configuration for sequestration of microcystins, four different porous membranes (polycarbonate, polyester, polyethersulfone and nylon) and two sorbents (Oasis HLB and Bondesil-LMS) were evaluated in the laboratory experiments, where samplers of different configuration were exposed to microcystins (microcystin-RR and microcystin-LR) for 14 days under steady conditions. We observed differences in sampling rates and amounts of accumulated microcystins depending on the sampler configurations. The samplers constructed with the polycarbonate membrane and Oasis HLB sorbent (2.75 mg/cm²) provided the highest sampling rates (0.022 L/day for microcystin-RR and 0.017 L/day for microcystin-LR). To the best of our knowledge, the present study is the first reporting application of passive samplers for microcystins, and our results demonstrate the suitability of this tool for monitoring cyanotoxins in water.     

Synthetic approach to grayanotoxins and asebotoxins: a new construction of the a-homograyanotoxane ring system

The tetracyclic compounds ～3 and ～4 corresponding to A-homograyanotoxane system were synthesised by a thermolysis of the benzocyclobutene ～8, followed by a Wagner-Meerwein rearrangement of the kaurane type of compounds ～15 and ～16.     

Development of a quality evaluation system for Panax quinquefolium. L based on HPLC chromatographic fingerprinting of seven major ginsenosides

A HPLC fingerprinting method based on the distribution and contents of seven major ginsenosides has been developed for the quality evaluation of Panax quinquefolium. L roots cultivated in China, Singapore and Canada. The method is ideally suited for the fingerprinting of P. quinquefolium. L samples or its derived products for sample authentication or quality control, e.g. pharmaceutical stability studies. Different extraction methods have been evaluated and a protocol established to maximize the gensinosides yields in routine operations. Hierarchical clustering analysis of the fingerprints demonstrates that the distribution and contents of ginsenosides in P. quinquefolium. L root vary depending on geographic location; and the quality of Jilin-cultivated P. quinquefolium. L roots is similar in composition to Canada-cultivated ones, which are generally considered among the best quality in P. quinquefolium. L.     

TMDS-Pd/C: a convenient system for the reduction of acetals to ethers

A simple and practical procedure for the reduction of acetals to ethers is described. It is based on the use of a 1,1,3,3-tetramethyldisiloxane (TMDS)-Pd/C system in the presence of a Brønsted acid as the co-catalyst. The reaction occurs under mild conditions and ethers are obtained in high yields.