<?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>2224-5421</journal-id>
<journal-title><![CDATA[Revista Cubana de Química]]></journal-title>
<abbrev-journal-title><![CDATA[Rev Cub Quim]]></abbrev-journal-title>
<issn>2224-5421</issn>
<publisher>
<publisher-name><![CDATA[Ediciones UO, Universidad de Oriente]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2224-54212021000100003</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Dicroísmo circular y fluorescencia en la evaluación del material de referencia químico-físico y biológico del nimotuzumab]]></article-title>
<article-title xml:lang="en"><![CDATA[Circular dichroism and fluorescence in the evaluation of the chemical-physical and biological reference material of nimotuzumab]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Porras-Vega]]></surname>
<given-names><![CDATA[Stephania]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Váldez-Núñez]]></surname>
<given-names><![CDATA[Roxana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gómez-Pérez]]></surname>
<given-names><![CDATA[Jose Arberto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ruiz-Ramirez]]></surname>
<given-names><![CDATA[Ingrid]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Romero-Batista]]></surname>
<given-names><![CDATA[Yamilet de la Rosa]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Centro de Inmunología Molecular (CIM)  ]]></institution>
<addr-line><![CDATA[La Habana ]]></addr-line>
<country>Cuba</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>04</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>04</month>
<year>2021</year>
</pub-date>
<volume>33</volume>
<numero>1</numero>
<fpage>3</fpage>
<lpage>21</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_arttext&amp;pid=S2224-54212021000100003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_abstract&amp;pid=S2224-54212021000100003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_pdf&amp;pid=S2224-54212021000100003&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN El establecimiento de un material de referencia es necesario para los ensayos de control de la calidad que se realizan a los medicamentos, garantizando mediciones confiables y trazables. En el Centro de Inmunología Molecular se elaboró un nuevo candidato a material de referencia para el Nimotuzumab con el objetivo de sustituir el vigente antes de su caducidad. En este trabajo se determinó la estructura secundaria y la estabilidad térmica de los materiales, mediante dicroísmo circular en el ultravioleta lejano y el plegamiento tridimensional mediante el ultravioleta cercano y fluorescencia intrínseca. Ambos materiales presentaron predominio de hojas &#946; (~ 42 %) y estabilidad termodinámica de ~ 71 oC. El plegamiento tridimensional mostró espectros muy similares en cuanto a la posición de las bandas de absorción de los residuos aromáticos y la intensidad de emisión de fluorescencia para la Tyr (336 nm) y para el Trp (337 nm).]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT The establishment of a reference material is necessary for the quality control tests that are carried out on drugs, guaranteeing reliable and traceable measurements. A new candidate reference material for Nimotuzumab was developed at the Center for Molecular Immunology with the aim of replacing the current one before its expiration. In this work, was determined the secondary structure and thermal stability of materials by circular dichroism in the ultraviolet distant and three-dimensional folding by means of the near ultraviolet and intrinsic fluorescence. Both materials presented a predominance of &#946; sheets (~ 42%) and thermodynamic stability of ~ 71 o C. The three-dimensional folding showed very similar spectra in terms of the position of the absorption bands of the aromatic residues and the intensity of fluorescence emission for the Tyr (336 nm) and for the Trp (337 nm).]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[nimotuzumab]]></kwd>
<kwd lng="es"><![CDATA[material de referencia]]></kwd>
<kwd lng="es"><![CDATA[dicroísmo circular]]></kwd>
<kwd lng="es"><![CDATA[fluorescencia intrínseca]]></kwd>
<kwd lng="en"><![CDATA[nimotuzumab]]></kwd>
<kwd lng="en"><![CDATA[reference material]]></kwd>
<kwd lng="en"><![CDATA[circular dichroism]]></kwd>
<kwd lng="en"><![CDATA[intrinsic fluorescence]]></kwd>
</kwd-group>
</article-meta>
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