Unraveling measurement in chemical analysis: 1. The analytical or calibration curve

Bahia Filho, Oscar; Prada, Patricia Regina; Meneghesso, Carla; Lanças, Fernando M.

Palavras-chave: Measurement uncertainty, analytical or calibration curve, HPLC, LC-MS/MS, quality system management, ISO 17025, GLP guidelines.

Resumo In a typical quantitative chemical analysis, the mathematical model used for the quantification process is responsible for the transformation of a measured unit into the quantity of interest. Once dealing with a series of operations, the possibility of propagation of errors is a real concern; the trustworthiness of all these operations must be well established and be known. The present work, the first one of a series, aims to present and discuss the contribution of the stage of construction of the analytical or calibration curve in the process of the assay by estimating its uncertainty based upon the ISO 17025 and GLP guidelines. The application of these concepts culminated in the elaboration of an operational procedure that was applied to the determination of fluazuron in animal tissues using liquid chromatography coupled to mass spectrometer (LC-MS/MS).

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