6533b7d7fe1ef96bd12683ce

RESEARCH PRODUCT

Quality control of Metamitron in agrochemicals using Fourier transform infrared spectroscopy in the middle and near range

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Abstract Two vibrational spectrometry-based methodologies were developed for Metamitron determination in pesticide formulations. Fourier transform-middle infrared (FT-MIR) procedure was based on the extraction of Metamitron by CHCl 3 and latter determination by peak area measurement between 1556 and 1533 cm −1 , corrected with a two points baseline established from 1572 to 1514 cm −1 . Fourier transform-near infrared (FT-NIR) determination was made after the extraction of Metamitron in acetonitrile and measuring the peak area between 6434 and 6394 cm −1 corrected using a two points baseline defined between 6555 and 6228 cm −1 . Repeatability, as relative standard deviation, of 5 independent measurements at mg g −1 concentration level, of 0.16% and 0.07% for MIR and NIR and a limit of detection of 0.03 and 0.004 mg g −1 were obtained for MIR and NIR, respectively. NIR determination provides a sample frequency of 120 h −1 , higher than that found by MIR and liquid chromatographic methods (60 and 15 h −1 , respectively). On the other hand, the NIR method reduces the solvent consumption and waste generation, to only 1 ml acetonitrile per sample as compared with 3.4 ml chloroform required for the MIR determination and 60 ml acetonitrile used in the chromatographic reference procedure. So, vibrational procedures can be considered serious alternatives to long and time consuming chromatographic methods usually recommended for quality control of commercially available pesticide formulations.