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Sabine Gei? Max Schneider Gerhild Donnevert Jürgen W. Einax Nicole Lettmann Aurélien Rey Herbert Lepper Birgit K?rner Theodor Prey Bettina Hilger Moana Engelke Marie-Pierre Strub Herve Adrien George Sawal Dirk L?ffler Tom Schillings Ines Hussy Philipp Steinbichl Sigrid Scharf Alexander Ruderisch Jorge E. Olmos F. Javier Santos Arantxa Bartolome Josep Caixach 《Accreditation and quality assurance》2012,17(1):15-25
A validation interlaboratory trial was carried out to prepare ISO 12010: Water quality??Determination of short-chain polychlorinated alkanes (SCCP) in water??Method using gas chromatography/mass spectrometry (GC-MS) and electron capture negative ionisation (ECNI). The task was to determine the sum of short-chain polychlorinated n-alkanes with carbon chain lengths of C10?CC13 and a chlorine content between 49% (g/100?g) and 67% (g/100?g) in water by GC-ECNI-MS. The quantification had to be performed by multiple linear regression as described in ISO/DIS 12010, the compulsory method. Samples distributed were real river samples, and waste water spiked with a target concentration of 0.4 and 0.6???g/L for the sum of SCCPs, i.e. a concentration around the environmental quality target level according to the European Water Framework Directive. The different types of water samples tested were surface water with <150?mg/L suspended matter, surface water with 0.5?g/L suspended matter, and filtered waste waster. The interlaboratory trial included the extraction of the water samples, a column chromatographic clean up, a concentration step, and integration of chromatographic unresolved complex mixtures as well as the calibration and quantification by multiple linear regression. The reproducibility standard deviation of the standard concentration was 11.9%. Reproducibility standard deviations of concentrations in the three different water samples between 27.8 and 34.2% were achieved by 10?C12 participating laboratories from six countries. 相似文献
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Sigrid Mennickent Ricardo Fierro Mario Vega Marta de Diego C. Gloria Godoy 《Journal of separation science》2009,32(9):1454-1458
An instrumental planar chromatographic (HPTLC) method for quantification of carbamazepine in human serum was developed using liquid‐liquid extraction with dichloromethane, fluorescence activation with perchloric acid 60%/ethanol/water (1:1:1, v/v) and fluorescence detection. Planar chromatographic separation was performed on precoated silica gel F254 HPTLC plates using a mixture of ethyl acetate/toluene/methanol/acetic acid glacial (5:4:0.5:0.5, v/v) as mobile phase. Densitometric detection was done at 366 nm. The method was validated for linearity, precision and accuracy. Linear calibration curves in the range of 3 and 20 ng/μL showed correlation coefficient of 0.998. The intra‐assay and inter‐assay precision, expressed as the RSD, were in the range of 0.41–1.24% (n = 3) and 2.17–3.17% (n = 9), respectively. The LOD was 0.19 ng, and the LOQ was 0.57 ng. Accuracy, calculated as percentage recovery, was between 98.98 and 101.96%, with a RSD not higher than 1.52%. The method was selective for the active principle tested. In conclusion, the method is useful for quantitative determination of carbamazepine in human serum. 相似文献
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