Neste trabalho desenvolveu-se um método para a determinação de 15 pesticidas em pão utilizando cromatografia gasosa acoplada à espectrometria de massas (GC-MS), operando no modo de ionização química negativa (NCI). No preparo da amostra utilizou-se acetonitrila contendo 1% (v/v) de ácido acético, na presença de acetato de sódio, citrato de sódio e sulfato de magnésio. O método foi validado avaliando os seguintes parâmetros: linearidade, limite de detecção (LOD), limite de quantificação (LOQ), precisão e exatidão. A faixa linear utilizada foi de 1,0-100 µg L-1. As recuperações foram consideradas satisfatórias apresentando valores entre 70 e 117%, com RSD < 17,6% para quase todos os compostos. O LOQ do método variou de 10 a 20 µg kg-1. O método demonstrou ser adequado, sensível e altamente seletivo para a análise multirresíduo de pesticidas em pão.

In this work a method for the determination of 15 pesticides in bread samples using gas chromatography coupled with mass spectrometry (GC-MS), operating in the negative chemical ionization mode (NCI) was developed and validated. For the extraction procedure acetonitrile containing 1% (v/v) acetic acid was used in presence of sodium acetate, sodium citrate and magnesium sulphate. The method was validated evaluating the following parameters: linearity, limit of detection (LOD), limit of quantification (LOQ), precision and accuracy. The linear range used was from 1.0 to 100 µg L-1. The recoveries had been considered satisfactory presenting values between 70 and 117% with RSD < 17.6% for almost all the compounds. The real method LOQ ranged from 10 to 20 µg kg-1. The method shown to be adequate for the multiresidue analysis of pesticides in bread and the GC-MS (NCI) proved to be sensitive and highly selective.

A rapid and efficient method for the analysis of histamine in wines using HPLC with fluorescence detection after derivatization was developed and validated. The method LOD and LOQ values were 0.25 and 0.50 mg L-1 respectively. The repeatability and intermediary precision for the instrument and for the method presented RSD values of 3.7 and 2.9%, and 6.0 and 5.6%, respectively. The recoveries were 95.5 and 89.9% for the fortification levels of 2 and 10 mg L-1. The method was applied to determine the histamine content in Cabernet Sauvignon wines, which presented values between 1.2 and 5.7 mg L-1.