Application of a truly one-point calibration for pesticide residue control by liquid chromatography–mass spectrometry

This paper presents the development of a simple fit-for-purpose Yes/No method for controlling pesticide residues in food by liquid chromatography tandem mass spectrometry (LC–MS/MS). A true one-point calibration (y = C, where C is a constant) was evaluated for its applicability, feasibility and performance in controlling pesticides in fruits. A process analytical technology approach was adopted. One-point calibrations equivalent to the maximum residual level (MRL) of a pesticide in a fruit were performed and used as the process and quality control parameters. The confidence level intervals were determined and used for controlling the pesticide residue levels in real fruit samples. Useful features of the proposed method, from practical point of view, include the easy access to historical data, their simple presentation, the simplicity of introducing new measurement data points, and these features make it an excellent diagnostic and analytical tool. This technique allows any method performance abnormality to be flagged early and reliable information on exceeding MRLs to be obtained quickly. This truly one-point calibration may find applications in any field where regulatory compliance requires that a measurand is shown to be within a particular limit.