Término solicitado: BILSEL, MINE/(22)
2 Registro/s encontrado/s en CAT
Tipo de Docum.: | artículo |
Título: | CCQM-K55.b (Aldrin) : Final report: october 2012. CCQM-K55.b key comparison on the characterization of organic substances for chemical purity |
Autor: | Westwood, Steven; Josephs, Ralf; Choteau, Tiphaine; Daireaux, Adeline; Mesquida, Charline; Wielgosz, Robert; Rosso, Adriana; Ruiz de Arechavaleta, Mariana; Davies, Stephen; Wang, Hongjie; Cristina Pires do Rego, Eliane; Marques Rodrigues, Janaína; de Freitas Guimarães, Evelyn; Barreto Sousa, Marcus Vinicius; Monteiro, Tânia Maria; Alves das Neves Valente, Laura; Marques Violante, Fernando Gustavo; Rubim, Renato; Almeida, Ribeiro; Baptista Quaresma, Maria Cristina; Nogueira, Raquel; Windust, Anthony; Dai, Xinhua; Li, Xiaomin; Zhang, Wei; Li, Ming; Shao, Mingwu; Wei, Chao; Wong, Siu-kay; Cabillic, Julie; Gantois, Fanny; Philipp, Rosemarie; Pfeifer, Dietmar; Hein, Sebastian; Klyk-Seitz, Urszula-Anna; Ishikawa, Keiichiro; Castro, Esther; Gonzalez, Norma; Krylov, Anatoly; Lin, Teo Tang; Kooi, Lee Tong; Fernandes-Whaley, M.; Prévoo, D.; Archer, M.; Visser, R.; Nlhapo, N.; de Vos, B.; Ahn, Seonghee; Pookrod, Preeyaporn; Wiangnon, Kanjana; Sudsiri, Nittaya; Muaksang, Kittiya; Cherdchu, Chainarong; Gören, Ahmet Ceyhan; Bilsel, Mine; LeGoff, Thierry; Bearden, Dan; Bedner, Mary; Duewer, David; Hancock, Diane; Lang, Brian; Lippa, Katrice; Schantz, Michele; Sieber, John |
Título Ser./Col.: | Metrología, 49 |
Autor Inst. Ser./Col.: | Bureau International des Poids et Mesures. BIPM. FR |
Idioma: | eng |
Datos de Edición: | s.l. IOP Publishing. 2012. |
Pág./Vol.: | 41p. |
Descriptores: | Metrología; Determinación de materia orgánica; Sustancias orgánicas; Incertidumbre; Calibración; Calibradores; Mediciones |
Resumen: | Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM K55.b, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2010/2011. Nineteen national measurement institutes and the BIPM participated. Participants were required to assign the mass fraction of aldrin present as the main component in the comparison sample for CCQM-K55.b which consisted of technical grade aldrin obtained from the National Measurement Institute Australia that had been subject to serial recrystallization and drying prior to sub-division into the units supplied for the comparison. Aldrin was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of medium structural complexity [molar mass range 300 Da to 500 Da] and low polarity (pKOW < −2) for which related structure impurities can be quantified by capillary gas phase chromatography (GC). The key comparison reference value (KCRV) for the aldrin content of the material was 950.8 mg/g with a combined standard uncertainty of 0.85 mg/g. The KCRV was assigned by combination of KCRVs assigned by consensus from participant results for each orthogonal impurity class. The relative expanded uncertainties reported by laboratories having results consistent with the KCRV ranged from 0.3% to 0.6% using a mass balance approach and 0.5% to 1% using a qNMR method. The major analytical challenge posed by the material proved to be the detection and quantification of a significant amount of oligomeric organic material within the sample and most participants relying on a mass balance approach displayed a positive bias relative to the KCRV (overestimation of aldrin content) in excess of 10 mg/g due to not having adequate procedures in place to detect and quantify the non-volatile content—specifically the non-volatile organics content—of the comparison sample. There was in general excellent agreement between participants in the identification and the quantification of the total and individual related structure impurities, water content and the residual solvent content of the sample. The comparison demonstrated the utility of 1H NMR as an independent method for quantitative analysis of high purity compounds. In discussion of the participant results it was noted that while several had access to qNMR estimates for the aldrin content that were inconsistent with their mass balance determination they decided to accept the mass balance result and assumed a hidden bias in their NMR data. By contrast, laboratories that placed greater confidence in their qNMR result were able to resolve the discrepancy through additional studies that provided evidence of the presence of non-volatile organic impurity at the requisite level to bring their mass balance and qNMR estimates into agreement. |
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URL: |
https://iopscience.iop.org/article/10.1088/0026-1394/49/1A/08014 |
Tipo de Docum.: | artículo |
Título: | CCQM-K138 : Determination of aflatoxins (AFB1, AFB2, AFG1, AFG2 and Total AFs) in Dried Fig. Key Comparison Track C. Final Report November 2018 |
Autor: | Goren, Ahmet C.; Gokcen, Taner; Gunduz, Simay; Bilsel, Mine; Koch, Mathias; Kakoulides, Elias; Giannikopoulou, Panagiota; Tang Wai-tong, Gary; Chan, Andy; Kneeteman, Estela; Mugenya, Isaac; Murııra, Geoffrey; Boonyakong, Cheerapa; Fernandes-Whaley, Maria; Krylov, Anatoliy; Mikheeva, Alena |
Título Ser./Col.: | Metrología, 56(1A) |
Autor Inst. Ser./Col.: | Bureau International des Poids et Mesures. BIPM. Paris. FR |
Idioma: | eng |
Datos de Edición: | s.l. IOP Publishing. 2019. |
Pág./Vol.: | pag. varia. |
Descriptores: | Aflatoxinas; Micotoxinas; Higos; Contaminación de alimentos; Mediciones; Calibración |
Resumen: | Nine NMI/DI participated in the CCQM Organic Analysis WG Track C Key Comparison CCQM-K138 Determination of aflatoxins (AFB1, AFB2, AFG1, AFG2 and Total AFs) in Dried Fig. Participants were requested to evaluate the mass fractions expressed in ng/g units, of aflatoxins B1, B2, G1, G2 and total aflatoxin in a dried fig. Aflatoxins are part of the mycotoxin family of contaminants which are a major issue for the food production industry internationally. The CCQM-K138 results ranged from 5.17 to 7.27 ng/g with an %RSD of 10.47 for AFB1, ranging from 0.60 to 0.871 ng/g with an %RSD of 11.69 for AFB2, ranging from 1.98 to 2.6 ng/g with an %RSD of 10.36 for AFG1, ranging from 0.06 to 0.32 ng/g with an %RSD of 35.6 for AFG2, and ranging from 8.29 to 10.31 ng/g with an %RSD of 7.69 for Total AFs. All participants based their analyses on Liquid Chromatography, seven utilizing LC-MS/MS with labelled internal standards and two utilizing HPLC-FLD. Linear Pool estimators were used to assign the Key Comparison Reference Values (KCRVs) for B1, B2, G1, G2 and total aflatoxins. Successful participation in CCQM-K138 demonstrates the following measurement capabilities in determining mass fraction of organic compounds, with molecular mass of 100 g/mol to 500 g/mol, having high polarity (pKow > -2), in mass fraction range from 0.05 ng/g to 500 ng/g in dried food matrices. It was noted that the results for CCQM-K138 represent a highly challenging set of measurands and involve very low level measurement of complex analytes in a situation where there is very limited availability of appropriate calibration materials. Due to the variability in results the degrees of equivalence for these analytes were reasonably large and this will need to be taken into consideration in the assessment of proposed CMCs. |
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Trabajo de INTI |
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URL: |
https://iopscience.iop.org/article/10.1088/0026-1394/56/1A/08008 |
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