<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0188-4999</journal-id>
<journal-title><![CDATA[Revista internacional de contaminación ambiental]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. Int. Contam. Ambient]]></abbrev-journal-title>
<issn>0188-4999</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Ciencias de la Atmósfera y Cambio Climático]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0188-49992017000400559</article-id>
<article-id pub-id-type="doi">10.20937/rica.2017.33.04.02</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[DISEÑO DE EXPERIMENTOS APLICADO EN LA OPTIMIZACIÓN DEL MÉTODO DE EXTRACCIÓN QuEChERS PARA LA DETERMINACIÓN DE PLAGUICIDAS ORGANOCLORADOS Y ORGANOFOSFORADOS EN SUELOS]]></article-title>
<article-title xml:lang="en"><![CDATA[DESIGN OF EXPERIMENTS APPLIED IN THE OPTIMIZATION OF THE QuEChERS EXTRACTION METHOD FOR THE DETERMINATION OF ORGANOCHLORINE AND ORGANOPHOSPHORUS PESTICIDES IN SOILS]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez-Lara]]></surname>
<given-names><![CDATA[Jina Marcela]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Páez Melo]]></surname>
<given-names><![CDATA[Martha Isabel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad del Valle Facultad de Ciencias Naturales y Exactas Departamento de Química]]></institution>
<addr-line><![CDATA[Cali ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2017</year>
</pub-date>
<volume>33</volume>
<numero>4</numero>
<fpage>559</fpage>
<lpage>573</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0188-49992017000400559&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0188-49992017000400559&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0188-49992017000400559&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN La metodología QuEChERS fue implementada para la extracción de catorce plaguicidas, diez organoclorados y cuatro organofosforados en muestras de suelo. El análisis se llevó a cabo por cromatografía de gases acoplado a una trampa de iones cuadrupolar en tándem (MS2). La extracción de los plaguicidas por la metodología seleccionada se ve afectada por diferentes factores, por tanto, la optimización del proceso de extracción incluyó el uso de dos diseños experimentales: un diseño ortogonal Taguchi inicial para determinar los factores de mayor influencia y posteriormente, un diseño factorial fraccionado 25-1 para determinar las condiciones óptimas preparativas. Los resultados mostraron que, el pH, el ultrasonido y el uso de adsorbentes de limpieza son factores poco relevantes en el proceso de preparación. Por el contrario, la cantidad de agua en la matriz, la relación muestra:solvente y las cantidades de MgSO4 y NaCl como sales de partición, juegan un rol importante dentro del proceso. El método final consistió en la hidratación del suelo con 5 mL de agua tipo I, utilizando 10 g de muestra, agitación por 1 min, adición de 10 mL de acetonitrilo como solvente extractor, desplazamiento salino con 2 g de MgSO4, 2 g de NaCl y limpieza final del extracto con 100 mg de octadecilsilano (C18), 10 mg de carbón grafitado y 600 mg de MgSO4 (por mL de extracto). Con el método obtenido, los plaguicidas estudiados pueden ser extraídos cuantitativamente de la matriz, con recuperaciones entre 70 y 120 %, coeficientes de variación menores al 10 % y límites de detección entre 4.9 y 21.7 &#956;g/kg.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT The QuEChERS methodology was implemented for the extraction of fourteen pesticides, ten organochlorines and four organophosphates in soil samples. The analysis was carried out by gas chromatography coupled to a quadrupole ion trap in tandem mode (MS2). The extraction of the pesticides by the selected methodology is affected by different factors. Therefore, the extraction process optimization included the use of two experimental designs: a Taguchi orthogonal design to determine most influential factors and, subsequently, a fractional factorial design 25-1 to determine the optimal preparative conditions. Results showed that the pH, sonication and the use of cleaning adsorbents are irrelevant factors in the preparatory process. By contrast, the amount of water in the matrix, the relationship sample:solvent, and the amounts of MgSO4 and NaCl as partition salts, play an important role in the process. The final method consisted in the soil hydration with 5 mL of water type I, using 10 g of sample, stirring for 1 min, addition of 10 mL of acetonitrile as extractor solvent, salting out with 2 g of MgSO4, 2 g NaCl, and final cleansing of the extract with 100 mg of octadecylsilane (C18), 10 mg of graphitized carbon and 600 mg of MgSO4 (per mL of extract). With the final method, the pesticides studied can be extracted quantitatively from the matrix, with recoveries between 70-120 %, coefficients of variation less than 10 % and detection limits between 4.9-21.7 µg/kg.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[contaminantes]]></kwd>
<kwd lng="es"><![CDATA[proceso de extracción]]></kwd>
<kwd lng="es"><![CDATA[análisis químico]]></kwd>
<kwd lng="es"><![CDATA[cromatografía de gases]]></kwd>
<kwd lng="en"><![CDATA[contaminants]]></kwd>
<kwd lng="en"><![CDATA[extractive process]]></kwd>
<kwd lng="en"><![CDATA[chemical analysis]]></kwd>
<kwd lng="en"><![CDATA[gas chromatography]]></kwd>
</kwd-group>
</article-meta>
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