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<article article-type="research-article" dtd-version="1.3" 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" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">chemicallytech</journal-id><journal-title-group><journal-title xml:lang="en">Fine Chemical Technologies</journal-title><trans-title-group xml:lang="ru"><trans-title>Тонкие химические технологии</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2410-6593</issn><issn pub-type="epub">2686-7575</issn><publisher><publisher-name>MIREA – Russian Technological University (RTU MIREA).</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.32362/2410-6593-2020-15-3-70-77</article-id><article-id custom-type="elpub" pub-id-type="custom">chemicallytech-1625</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ANALYTICAL METHODS IN CHEMISTRY AND CHEMICAL TECHNOLOGY</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>АНАЛИТИЧЕСКИЕ МЕТОДЫ В ХИМИИ И ХИМИЧЕСКОЙ ТЕХНОЛОГИИ</subject></subj-group></article-categories><title-group><article-title>Quantification of polysorbate 80 in biopharmaceutical formulations implementing an optimized colorimetric approach</article-title><trans-title-group xml:lang="ru"><trans-title>Определение полисорбата 80 в биофармацевтических препаратах с помощью оптимизированной колориметрической методики</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5842-7344</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Серегин</surname><given-names>А. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Seregin</surname><given-names>A. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Cерегин Александр Сергеевич, аспирант</p><p>117545, Москва, 1-й Дорожный проезд, д. 1</p></bio><bio xml:lang="en"><p>Aleksandr S. Seregin, Postgraduate Student</p><p>1, 1st Dorozhnyi pr., Moscow, 117545</p></bio><email xlink:type="simple">penpney@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4161-5880</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Орлова</surname><given-names>Н. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Orlova</surname><given-names>N. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Орлова Наталья Владимировна, кандидат биологических наук, заведующая испытательной лабораторией</p><p>117545, Москва, 1-й Д рожный проезд, д. 1</p></bio><bio xml:lang="en"><p>Natalya V. Orlova, Cand. of Sci. (Biology), Head of Research Laboratory</p><p>1, 1st Dorozhnyi pr., Moscow, 117545</p></bio><email xlink:type="simple">orlova.chemist@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-0110-8323</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Аскретков</surname><given-names>А. Д.</given-names></name><name name-style="western" xml:lang="en"><surname>Askretkov</surname><given-names>A. D.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Аскретков Александр Дмитриевич, старший химик-аналитик</p><p>117246, Москва, Научный проезд, д. 8, стр. 1</p></bio><bio xml:lang="en"><p>Aleksandr D. Askretkov, Chief Chemist-Analyst</p><p>8, b. 1, Nauchnyi pr., Moscow, 117246</p></bio><email xlink:type="simple">askretkov.a.d@gmail.com</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5542-982X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Зыбин</surname><given-names>Д. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Zybin</surname><given-names>D. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Зыбин Дмитрий Игоревич, старший химик-аналитик. ResearсherID P-8049-2016</p><p>117246, Москва, Научный проезд, д. 8, стр. 1</p></bio><bio xml:lang="en"><p>Dmitry I. Zybin, Chief Chemist-Analyst. ResearсherID P-8049-2016</p><p>8, b. 1, Nauchnyi pr., Moscow, 117246</p></bio><email xlink:type="simple">zybin@pharmapark.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Серегин</surname><given-names>Д. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Seregin</surname><given-names>Yu. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Серегин Юрий Александрович, кандидат биологических наук, заместитель директора. ResearсherID I-1874-2017</p><p>117545, Москва, 1-й Дорожный проезд, д. 1</p></bio><bio xml:lang="en"><p>Yuri A. Seregin, Cand. of Sci. (Biology), Deputy Director. ResearсherID I-1874-2017</p><p>1, 1st Dorozhnyi pr., Moscow, 117545</p></bio><email xlink:type="simple">yuriy.seregin@pharmapark.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Национальный исследовательский центр «Курчатовский институт» – ГосНИИгенетика</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Scientific Center “Kurchatov Institute,” Research Institute for Genetics and Selection of Industrial Microorganisms</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ООО «ФАРМАПАРК»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>PHARMAPARK</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2020</year></pub-date><pub-date pub-type="epub"><day>06</day><month>07</month><year>2020</year></pub-date><volume>15</volume><issue>3</issue><fpage>70</fpage><lpage>77</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Seregin A.S., Orlova N.V., Askretkov A.D., Zybin D.I., Seregin Y.A., 2020</copyright-statement><copyright-year>2020</copyright-year><copyright-holder xml:lang="ru">Серегин А.С., Орлова Н.В., Аскретков А.Д., Зыбин Д.И., Серегин Д.И.</copyright-holder><copyright-holder xml:lang="en">Seregin A.S., Orlova N.V., Askretkov A.D., Zybin D.I., Seregin Y.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.finechem-mirea.ru/jour/article/view/1625">https://www.finechem-mirea.ru/jour/article/view/1625</self-uri><abstract><sec><title>Objectives</title><p>Objectives. We hereby describe an improvement of a previously developed quantification technique for polysorbate 80 in biopharmaceutical formulations (darbepoetin alfa and eculizumab) and report the validation of the new approach.</p></sec><sec><title>Methods</title><p>Methods. Polysorbate was isolated from analyte samples by protein precipitation using an organic solvent, followed by supernatant evaporation in vacuum. Polysorbate was derivatized using a ferric thiocyanate reagent and extracted into an organic phase; the relevant optical density measurements were performed.</p></sec><sec><title>Results</title><p>Results. We established the optimal conditions for each step of the analysis procedure. The accuracy was 97–102% in the tested analytical range, the relative standard deviation did not exceed 5%, and the limit of quantification was 0.01 mg/mL.</p></sec><sec><title>Conclusions</title><p>Conclusions. The reported approach is highly sensitive; polysorbate isolation and quantification do not depend on the matrix or, most importantly, the protein.</p></sec></abstract><trans-abstract xml:lang="ru"><sec><title>Цели</title><p>Цели. В данной работе была усовершенствована ранее разработанная методика определения полисорбата 80 в биотехнологических препаратах (дарбэпоэтин альфа, экулизумаб), а также проведена ее валидация.</p></sec><sec><title>Методы</title><p>Методы. Полисорбат извлекали из пробы осаждением белка органическим растворителем, затем выпаривали супернатант в вакууме. Полисорбат дериватизировали оптимизированным железо–тиоцианатным реагентом; дериват экстрагировали в слой органического растворителя и измеряли оптическую плотность.</p></sec><sec><title>Результаты</title><p>Результаты. Были установлены оптимальные условия для каждой стадии методики. Правильность находится в диапазоне степени извлечения 97–102%, относительное стандартное отклонение составляет не более 5%, предел количественного определения методики 0.01 мг/мл.</p></sec><sec><title>Выводы</title><p>Выводы. Представленная методика имеет высокую чувствительность. Извлечение и определение полисорбата не зависят от матрикса пробы – прежде всего, от присутствующего белка.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>валидация</kwd><kwd>дарбэпоэтин альфа</kwd><kwd>экулизумаб</kwd><kwd>полисорбат</kwd><kwd>осаждение</kwd><kwd>тиоцианат железа</kwd></kwd-group><kwd-group xml:lang="en"><kwd>validation</kwd><kwd>darbepoetin alfa</kwd><kwd>eculizumab</kwd><kwd>polysorbate</kwd><kwd>precipitation</kwd><kwd>ferric thiocyanate</kwd></kwd-group><funding-group><funding-statement xml:lang="en">This article has been edited for English language and spelling by Enago, an editing brand of Crimson Interactive Inc.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Askretkov A.D., Isaykina P.M., Cherepushkin S.A., Orlova N.V. Determination of polysorbates by spectrophotometry in drugs based on recombinant proteins. 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