Certified reference standard of lambda-cyhalothrin (>99%% purity) were purchased from Dr. Ehrenstorfer GmbH (Augsburg, Germany).
To reduce mass spectrometer contamination, a diverter valve was used to switch the LC eluant to the waste container except for the 6 minute window of LC eluant bracketing the retention time for DA that was sent to the MS. Retention time of DA in samples was determined based on the retention time observed with a certified reference standard (NRC Canada, Halifax, Canada).
Solutions were prepared in 0.1 Mnitric acid (Aristar grade, Merck Scientific, West Drayton, UK), and the assay was calibrated against Pt-containing solutions prepared by serial dilution from a certified reference standard.
The accuracy of the ICP-MS analytical protocol was periodically evaluated via the analysis of certified reference standard materials (whole rock powders) BE-N and DR-N available from the SARM laboratory at the CRPG (Centre de Recherches Pétrographiques et Géologiques).
Certified reference standards 6-acetylmorphine, morphine, buprenorphine, hydromorphone, norbuprenorphine, hydrocodone, oxycodone, oxymorphone, alpha hydroxy alprazolam, alprazolam, nordiazepam, oxazepam, and temazepam were purchased from Cerilliant (Round Rock, TX, USA).
The Applied business unit includes quality components and kits, chemical reagents, critical raw materials and certified reference standards, provide customized solutions to and constitute critical components and materials for diagnostic companies, testing laboratories and industrial companies.
However, the absence of metabolic studies and certified reference standards precluded the verification of the other detected substances as metabolites.
Certified reference standards (and MSDS) for cylindrospermopsin and several saxitoxin analogues are supplied by the Canadian National Research Council's Institute for Marine Biosciences, see [ 48].
Certified reference standards (OA, DTX-1, and DTX-2) from the National Research Council (Halifax, Nova Scotia, Canada) were used for verification of retention time and equimolar response.
A four-point curve was generated by using organometallic certified reference standards Multi-Element Metallo-Organic CRM, Custom Standard 701 and Matrix: 75 cSt Hydrocarbon Oil (VHG Laboratories, Manchester, NH).
These were used to determine total alkalinity (TA) by potentiometric titration (Metrohm 888 Titrando) using certified reference standards (Dickson et al. 2007) and total dissolved carbon (TCO2) using the Apollo SciTech DIC Analyzer AS-C3 (http://www.apolloscitech.com/DIC.htm).
