Experience with Certified Reference Material Proficiency Testing for Quality Control of Wheat

1998 ◽  
Vol 6 (A) ◽  
pp. A53-A61
Author(s):  
Judit Budai ◽  
Judit Fükó

The Chemical Section of OMH1,2 embarked on the preparation of a series of wheat samples as Certified Reference Materials (CRMs) in 1992. The certification processes were carried out according to the recommendations of ISO. Since then we have developed a series of flour samples as well. The investigations of the long-term stability and the application of wheat and flour CRMs are continuous. Wheat is one of the most widely grown crops in Hungary and it is one of the major determining factors of the economy. Its uniform and objective qualification is of great importance. There are well-equipped laboratories available with sufficient experience but, as the proficiency testing regularly showed, certified samples need to be used to achieve exact and uniform measuring results.

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4370
Author(s):  
Liping Fang ◽  
Linyan Huang ◽  
Gang Yang ◽  
Yang Jiang ◽  
Haiping Liu ◽  
...  

Water matrix certified reference material (MCRM) of volatile organic compounds (VOCs) is used to provide quality assurance and quality control (QA/QC) during the analysis of VOCs in water. In this research, a water MCRM of 28 VOCs was developed using a “reconstitution” approach by adding VOCs spiking, methanol solution into pure water immediately prior to analysis. The VOCs spiking solution was prepared gravimetrically by dividing 28 VOCs into seven groups, then based on ISO Guide 35, using gas chromatography-mass spectrometry (GC-MS) to investigate the homogeneity and long-term stability. The studies of homogeneity and long-term stability indicated that the batch of VOCs spiking solution was homogeneous and stable at room temperature for at least 15 months. Moreover, the water MCRM of 28 VOCs was certified by a network of nine competent laboratories, and the certified values and expanded uncertainties of 28 VOCs ranged from 6.2 to 17 μg/L and 0.5 to 5.3 μg/L, respectively.


2011 ◽  
Vol 47 (2) ◽  
pp. 339-350 ◽  
Author(s):  
Raquel Nogueira ◽  
Eliane Cristina Pires do Rego ◽  
Marcus Vinicius Barreto Sousa ◽  
Wagner Wollinger ◽  
Thaís Elias da Silva ◽  
...  

This paper describes the studies performed with the candidate Certified Reference Material (CRM) of captopril, the first CRM of an active pharmaceutical ingredient (API) in Brazil, including determination of impurities (organic, inorganic and volatiles), homogeneity testing, short- and long-term stability studies, calculation of captopril content using the mass balance approach, and estimation of the associated measurement uncertainty.


2020 ◽  
Vol 15 ◽  
pp. 155892502094116 ◽  
Author(s):  
Mingqi Guo ◽  
Yun He ◽  
Li Jiang ◽  
Qingbo Yang ◽  
Jianli Liu ◽  
...  

At present, many well-known brands of washing machines in the market are equipped with dye transfer inhibition washing procedures. However, there is no standardized sample available for the evaluation of the dye transfer inhibition washing procedure, and there is no comparability and access standard of the high-quality washing machine with the related functions. In this article, the certified reference materials for the evaluation of the dye transfer inhibition function will be prepared, which consist of certified reference material of white cotton fabric and that of dyed cotton fabric. The certified reference material of white fabric is made of bleached plain fabric, and that of dyed fabric is made with different reactive red dyes and dyeing processes. The size and manufacturing process of the whole set of standardized samples for the evaluation of dye transfer inhibition are selected and determined through experiments. The preparation of the standardized sample for the evaluation of dye transfer inhibition will improve the research and design of the functional washing procedure, which can better solve the pain point when dark and light clothes are washed together.


2015 ◽  
Vol 7 (11) ◽  
pp. 4763-4768 ◽  
Author(s):  
Dezhi Yang ◽  
Fengfeng Wang ◽  
Li Zhang ◽  
Yang Lv

Certified reference materials (CRMs) with good metrological characteristics are essential tools to guarantee the reliability and validity of analytical measurements.


1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.


2019 ◽  
Vol 15 (5) ◽  
pp. 553-559
Author(s):  
Ningbo Gong ◽  
Baoxi Zhang ◽  
Kun Hu ◽  
Zhaolin Gao ◽  
Guanhua Du ◽  
...  

Background: Formononetin is a common soy isoflavonoid that can be found abundantly in many natural plants. Previous studies have shown that formononetin possesses a variety of activities which can be applied for various medicinal purposes. Certified Reference Materials (CRMs) play a fundamental role in the food, traditional medicine and dietary supplement fields, and can be used for method validation, uncertainty estimation, as well as quality control. Methods: The purity of formononetin was determined by Differential Scanning Calorimetry (DSC), Coulometric Titration (CT) and Mass Balance (MB) methods. Results: This paper reports the sample preparation methodology, homogeneity and stability studies, value assignment, and uncertainty estimation of a new certified reference material of formononetin. DSC, CT and MB methods proved to be sufficiently reliable and accurate for the certification purpose. The purity of the formononetin CRM was therefore found to be 99.40% ± 0.24 % (k = 2) based on the combined value assignments and the expanded uncertainty. Conclusion: This CRM will be a reliable standard for the validation of the analytical methods and for quality assurance/quality control of formononetin and formononetin-related traditional herbs, food products, dietary supplements and pharmaceutical formulations.


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