Fourier transform infrared spectrometric determination of Malathion in pesticide formulations
Quintas, G.; Morales Noe, A.; Armenta, S.; Garrigues, S.; Guardia, M. de la
Analytica Chimica Acta 502(2): 213-220
2004
ISSN/ISBN: 0003-2670
DOI: 10.1016/j.aca.2003.10.044
Accession: 004168116
An environmentally friendly methodology has been developed for quality control analysis of emulsifiable concentrate pesticide formulations containing Malathion as active ingredient, using flow injection analysis (FIA)-Fourier transform infrared (FTIR) spectrometry. Five microlitres samples were directly injected into a 3 ml closed FIA manifold, in which 2 ml of CHCl3 was re-circulated at 1.96 ml min-1. After homogenization and sample measurement, 2 micro l volumes of a Malathion standard were injected, taking absorbance measurements after each injection. Peak height of the chemigrams, established from peak area values between 1027 and 1017 cm-1, corrected with a baseline fixed from 1087 to 993 cm-1 were employed for Malathion quantification using the standard addition approach, after reaching the steady state for every injection. A limit of detection of 12 micro g ml-1 was achieved. Results found by standard addition-FTIR in commercially available samples showed a good correlation with those obtained by the reference gas chromatography-flame ionization detection procedure.