The validation of chromatographic methods is a costly process, however necessary, especially with regard to the validation of methods that accurately determine concentrations of pesticides in different environmental compartments. This research aimed at the development and validation of a simple and fast method for the determination of chlorpyrifos concentrations in water by means of a gas chromatograph with electron capture detection (GC/ECD), and to investigate chlorpyrifos dynamics of adsorption in a Rhodic Ferralsol in Southern Brazilian conditions. The developed chromatographic method was based in EPA 8141 method. Parameters to be checked for method validation were: Selectivity/specificity, linearity, precision, accuracy, robustness, limit of detection (LOD) and limit of quantitation (LOQ). Were employed the following methodologies for the validation process: ANVISA Resolution 899, DOQ-CGCRE-008 and FDA Bioanalytical Method Validation Guide. Also, through laboratory tests, the sorption dynamics of chlorpyrifos in Rhodic Ferralsol was evaluated. Thus, the soil was contaminated with increasing concentrations of chlorpyrifos, which were subjected to solid-liquid extraction with SPE cartridge Chromabond® C18 ec. The obtained results were submitted to the models of Langmuir, Freundlich, Dubinin-Radushkevich and Sips. By this method, chlorpyrifos peaks are obtained at 16.9 min, demonstrating practicality and low cost. This method exhibits precision and sensitivity, with satisfactory LQ and LQ values. The models of Langmuir, Freundlich, Dubinin-Radushkevich and Sips suggest the occurrence of simultaneous adsorption in mono and multilayer of chlorpyrifos in Rhodic Ferralsol colloids, as well as the predominance of a chemical, high energy binding process (irreversible). However, the chemisorption of chlorpyrifos is more related to the good fit found for Dubinin-Radushkevich sorption energy values (9.861 and 11.079 KJ mol⁻¹) and Q_m values estimated by Langmuir (485.55 and 389.61 μg g⁻¹ for linear and nonlinear model).

中文翻译：

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水中GC / ECD测定氯吡咯烷酮及其在RHODIC FERRALSOL中的吸附机理研究。

色谱方法的验证是一个昂贵的过程，但是是必要的，尤其是在准确确定不同环境隔室中农药浓度的方法方面。这项研究旨在开发和验证一种简单快速的方法，该方法通过带有电子捕获检测器（GC / ECD）的气相色谱法测定水中的毒死rif浓度，并研究毒死rif在Rhodic Ferralsol中的吸附动力学。巴西南部的条件。所开发的色谱方法基于EPA 8141方法。用于方法验证的检查参数为：选择性/特异性，线性，精度，准确性，鲁棒性，检测限（LOD）和定量限（LOQ）。验证过程采用以下方法：ANVISA第899号决议，DOQ-CGCRE-008和FDA生物分析方法验证指南。此外，通过实验室测试，评估了毒死rif在Rhodic Ferralsol中的吸附动力学。因此，土壤被浓度不断增加的毒死increasing污染了，毒死with用SPE滤筒C18 ec进行了固液萃取。将获得的结果提交给Langmuir，Freundlich，Dubinin-Radushkevich和Sips模型。通过这种方法，毒死rif峰在16.9分钟处获得，证明了实用性和低成本。该方法具有精确度和灵敏度，并具有令人满意的LQ和LQ值。Langmuir，Freundlich，Dubinin-Radushkevich和Sips建议在Rhodic Ferralsol胶体中毒死rif的单层和多层中同时发生吸附，以及化学，高能结合过程（不可逆）的优势。但是，毒死rif的化学吸附与Dubinin-Radushkevich吸附能值（9.861和11.079 KJ mol）的良好拟合关系更大。^-1）和Q _m值由Langmuir估计（线性和非线性模型为485.55和389.61μgg ^-1）。