<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.3 20210610//EN" "JATS-journalpublishing1-3.dtd">
<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="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">pharmjournal</journal-id><journal-title-group><journal-title xml:lang="ru">Разработка и регистрация лекарственных средств</journal-title><trans-title-group xml:lang="en"><trans-title>Drug development &amp; registration</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2305-2066</issn><issn pub-type="epub">2658-5049</issn><publisher><publisher-name>LLC «CPHA»</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.33380/2305-2066-2024-13-1-1530</article-id><article-id custom-type="elpub" pub-id-type="custom">pharmjournal-1692</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="ru"><subject>ПОИСК И РАЗРАБОТКА НОВЫХ ЛЕКАРСТВЕННЫХ СРЕДСТВ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>RESEARCH AND DEVELOPMENT OF NEW DRUG PRODUCTS</subject></subj-group></article-categories><title-group><article-title>Оптимизация способа спектрофлуориметрического определения примеси алюминия в субстанциях</article-title><trans-title-group xml:lang="en"><trans-title>Optimization of the Method for Spectrofluorimetric Determination of Aluminum Impurities in Substances</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-4716-7866</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Вишняков</surname><given-names>Е. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Vishnyakov</surname><given-names>E. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>197022, г. Санкт-Петербург, ул. Профессора Попова, 14, лит. А</p></bio><bio xml:lang="en"><p>14A, Prof. Popova str., Saint-Petersburg, 197022</p></bio><email xlink:type="simple">evgeniy.vishnyakov@pharminnotech.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/0009-0007-6400-9951</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Толстикова</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Tolstikova</surname><given-names>A. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>197022, г. Санкт-Петербург, ул. Профессора Попова, 14, лит. А</p></bio><bio xml:lang="en"><p>14A, Prof. Popova str., Saint-Petersburg, 197022</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2573-6036</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Генералова</surname><given-names>Ю. Э.</given-names></name><name name-style="western" xml:lang="en"><surname>Generalova</surname><given-names>J. E.</given-names></name></name-alternatives><bio xml:lang="ru"><p>197022, г. Санкт-Петербург, ул. Профессора Попова, 14, лит. А</p></bio><bio xml:lang="en"><p>14A, Prof. Popova str., Saint-Petersburg, 197022</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-9328-457X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Калдыбаева</surname><given-names>А. К.</given-names></name><name name-style="western" xml:lang="en"><surname>Kaldybaeva</surname><given-names>A. K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>050000, г. Алматы, ул. Толе Би, д. 88, к. 4</p></bio><bio xml:lang="en"><p>88/4, Tole Bi str., Almaty, 050000</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2942-1015</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Тернинко</surname><given-names>И. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Terninko</surname><given-names>I. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>197022, г. Санкт-Петербург, ул. Профессора Попова, 14, лит. А</p></bio><bio xml:lang="en"><p>14A, Prof. Popova str., Saint-Petersburg, 197022</p></bio><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Федеральное государственное бюджетное образовательное учреждение высшего образования «Санкт-Петербургский государственный химико-фармацевтический университет» Министерства здравоохранения Российской Федерации (ФГБОУ ВО СПХФУ Минздрава России)<country>Россия</country></aff><aff xml:lang="en">Saint-Petersburg State Chemical and Pharmaceutical University<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">Казахский национальный медицинский университет имени С. Д. Асфендиярова (КазНМУ)<country>Казахстан</country></aff><aff xml:lang="en">Asfendiyarov Kazakh National Medical University<country>Kazakhstan</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2024</year></pub-date><pub-date pub-type="epub"><day>25</day><month>12</month><year>2023</year></pub-date><volume>13</volume><issue>1</issue><fpage>18</fpage><lpage>25</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Вишняков Е.В., Толстикова А.А., Генералова Ю.Э., Калдыбаева А.К., Тернинко И.И., 2024</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="ru">Вишняков Е.В., Толстикова А.А., Генералова Ю.Э., Калдыбаева А.К., Тернинко И.И.</copyright-holder><copyright-holder xml:lang="en">Vishnyakov E.V., Tolstikova A.A., Generalova J.E., Kaldybaeva A.K., Terninko I.I.</copyright-holder><license 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.pharmjournal.ru/jour/article/view/1692">https://www.pharmjournal.ru/jour/article/view/1692</self-uri><abstract><sec><title>Введение</title><p>Введение. Оценка содержания примесей является важнейшим этапом в подтверждении безопасности и эффективности при контроле качества лекарственного средства. Алюминий, являясь допустимой примесью в ряде фармацевтических субстанций, способен пагубно воздействовать на организм человека, вследствие чего его содержание нормируется. Примесь алюминия в Государственной фармакопее РФ XV определяется спектрофлуориметрическим методом с применением лиганда – 8-гидроксихинолина в хлороформе. В настоящей работе предлагается заменить 8-гидроксихинолин на более доступный рутин, который также образует с металлами флуоресцирующие комплексы. Данный подход предполагает исключение из пробоподготовки этапа экстракции комплекса алюминия в хлороформ, что способствует повышению точности методики, а замена хлороформа положительным образом сказывается на безопасности.</p></sec><sec><title>Цель</title><p>Цель. Создание альтернативного метода спектрофлуориметрического определения примеси алюминия с помощью рутина на примере субстанции калия хлорид.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. В качестве материалов исследования использовали следующие субстанции и реактивы: ГСО алюминий-иона, 1 мг/мл (ООО «ЭКРОСХИМ», Россия); ГСО железо-иона (II), 1 мг/мл (ООО «ЭКРОСХИМ», Россия); ГСО цинк-иона, 1 мг/мл (ООО «ЭКРОСХИМ», Россия); ГСО свинец-иона, 1 мг/мл (ООО «ЭКРОСХИМ», Россия); ГСО никель-иона, 1 мг/мл (ООО «ЭКРОСХИМ», Россия); ГСО медь-иона, 1 мг/мл (ООО «ЭКРОСХИМ», Россия); стандарт катиона хрома (III), 1 мг/мл (имп., Sigma-Aldrich, США); рутин (имп., Sichuan Guangsong Pharmaceutical Co., Ltd., Китай); аммоний уксуснокислый (имп., Molekula GmbH, Германия), уксусная кислота ледяная (х. ч., АО «База № 1 Химреактивов», Россия); калия хлорид (ФС, ООО «МЗХР», Россия). Спектрофлуориметрическое исследование проводилось на приборе FL 6500 (PerkinElmer Inc., США). Содержание примеси алюминия также оценивалось с использованием атомно-эмиссионного спектрометра с индуктивно связанной плазмой (АЭС-ИСП) Optima 8000 (PerkinElmer Inc., США) и стандартного образца Multi-Element Solution (PerkinElmer Inc., США).</p></sec><sec><title>Результаты и обсуждение</title><p>Результаты и обсуждение. Подход, приведенный в статье, исключает использование 8-гидроксихинолина в хлороформе и заменяет его на рутин в 70%-м спирте этиловом. Комплекс алюминия с рутином имеет длину волны возбуждения при 445 нм и длину волны эмиссии при 565 нм. Предложенная методика была апробирована на субстанции калия хлорид для оценки показателя «Алюминий», содержание которого не должно превышать 0,0001 %. Валидация методики осуществлялась по трем параметрам: «специфичность», «линейность» и «предел обнаружения» (ОФС.1.1.0012). Сопоставление полученных данных проводилось с применением атомно-эмиссионной спектроскопии, в ходе которой была доказана релевантность методики.</p></sec><sec><title>Заключение</title><p>Заключение. Разработан эргономичный способ спектрофлуориметрического определения примеси алюминия с помощью рутина с апробацией на субстанции калия хлорид. Результаты, полученные в ходе эксперимента, были подтверждены методом АЭС-ИСП.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. Evaluation of the content of impurities is the most important step in confirming the safety and efficacy in the quality control of the medicinal product. Aluminum, being an acceptable impurity in a number of pharmaceutical substances, can adversely affect the human body, as a result of which its content is normalized. The admixture of aluminum in the State Pharmacopoeia of the Russian Federation XV is determined by the spectrofluorimetric method using the ligand – 8-hydroxyquinoline in chloroform. In the present work, it is proposed to replace 8-hydroxyquinoline with the more accessible rutin, which also forms fluorescent complexes with metals. This approach involves the exclusion of the stage of extraction of the aluminum complex into chloroform from sample preparation, which improves the accuracy of the technique, and the replacement of chloroform has a positive effect on safety.</p></sec><sec><title>Aim</title><p>Aim. To create an alternative approach for the spectrofluorimetric determination of aluminum impurities using rutin and "potassium chloride" as an active pharmaceutical ingredient.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The following substances and reagents were used as research materials: CRS of aluminum ion 1 mg/ml (LLC "EKROSHIM", Russia), CRS of iron ion (II) 1 mg/ml (LLC "EKROSHIM", Russia), CRS of zinc ion 1 mg/ml (LLC "EKROSHIM", Russia), CRS of lead-ion 1 mg/ml (LLC "EKROSHIM", Russia), CRS nickel-ion 1 mg/ml (LLC "EKROSHIM", Russia), CRS copper-ion 1 mg/ml (LLC "EKROSHIM", Russia), chromium (III) cation standard 1 mg/ml (imp., Sigma-Aldrich, USA) rutin (imp., Sichuan Guangsong Pharmaceutical Co., Ltd., China), ammonium acetic acid (imp., Molekula GmbH, Germany), glacial acetic acid (chemically pure, JSC "Base No. 1 Himreaktivov", Russia), potassium chloride (pharmaceutical substance, LLC "MZHR", Russia). The spectrofluorimetric study was carried out on an FL 6500 instrument (PerkinElmer Inc., USA). The aluminum impurity content was also evaluated using an Optima 8000 inductively coupled plasma atomic emission spectrometer (ICP AES) (PerkinElmer Inc., USA) and a Multi-Element Solution standard sample (PerkinElmer Inc., USA).</p></sec><sec><title>Results and discussion</title><p>Results and discussion. The approach given in the article eliminates the use of 8-hydroxyquinoline in chloroform and replaces it with rutin in 70 % ethyl alcohol. The aluminum-rutin complex has an excitation wavelength at 445 nm and an emission wavelength at 565 nm. The proposed method was tested on the substance "Potassium chloride" to assess the indicator "Aluminum", the content of which should not exceed 0.0001 %. Method validation was carried out according to three parameters "Specificity", "Linearity" and "Limit of detection". Comparison of the data obtained was carried out using atomic emission spectroscopy, during which the relevance of the technique was proved.</p></sec><sec><title>Conclusion</title><p>Conclusion. An ergonomic approach has been developed for the spectrofluorimetric determination of aluminum impurities using rutin with approbation on the substance "Potassium chloride". The results obtained during the experiment were confirmed by the ICP AES method.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>спектрофлуориметрия</kwd><kwd>рутин</kwd><kwd>алюминий</kwd><kwd>примеси</kwd><kwd>валидация</kwd><kwd>атомно-эмиссионная спектрометрия</kwd></kwd-group><kwd-group xml:lang="en"><kwd>spectrofluorimetry</kwd><kwd>rutin</kwd><kwd>aluminum</kwd><kwd>impurities</kwd><kwd>validation</kwd><kwd>atomic emission spectrometry</kwd></kwd-group><funding-group xml:lang="ru"><funding-statement>Результаты работы получены с использованием оборудования ЦКП «Аналитический центр» ФГБОУ ВО СПХФУ Минздрава России в рамках соглашения № 075-15-2021-685 от 26 июля 2021 года при финансовой поддержке Минобрнауки России.</funding-statement></funding-group><funding-group xml:lang="en"><funding-statement>The results of the work were obtained using the equipment of the Center for Collective Use "Analytical Center" of the Federal State. Budgetary Educational University of Higher Education SPCPU of the Ministry of Health of Russia in the framework of agreement № 075-15-2021-685 dated July 26, 2021 with the financial support of the Ministry of Education and Science of Russia.</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">Эпштейн Н. А. Трансфер методик определения примесей: сравнительное испытание, валидация, критерии приемлемости (обзор). Разработка и регистрация лекарственных средств. 2021;10(2):137–146. DOI: 10.33380/2305-2066-2021-10-2-137-146.</mixed-citation><mixed-citation xml:lang="en">Epshtein N. A. Transfer of Impurities Determination Methods: Comparative Testing, Validation, Acceptance Criteria (Review). Drug development &amp; registration. 2021;10(2):137–146. (In Russ.) DOI: 10.33380/2305-2066-2021-10-2-137-146.</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">Внешние стандартные образцы или относительные факторы отклика: вопросы количественного определения примесей в фармацевтических препаратах. Разработка и регистрация лекарственных средств. 2021;10(3):16–20.</mixed-citation><mixed-citation xml:lang="en">External Reference Standards or Relative Response Factors: Considerations for Quantitation of Impurities in Pharmaceuticals. Drug development &amp; registration. 2021;10(3):16–20. (In Russ.)</mixed-citation></citation-alternatives></ref><ref id="cit3"><label>3</label><citation-alternatives><mixed-citation xml:lang="ru">Rajagopalan R. Review of regulatory guidance on impurities. Handbook of Isolation and Characterization of Impurities in Pharmaceuticals. 2004;27–37. DOI:10.1016/s0149-6395(03)80004-1.</mixed-citation><mixed-citation xml:lang="en">Rajagopalan R. Review of regulatory guidance on impurities. Handbook of Isolation and Characterization of Impurities in Pharmaceuticals. 2004;27–37. DOI:10.1016/s0149-6395(03)80004-1.</mixed-citation></citation-alternatives></ref><ref id="cit4"><label>4</label><citation-alternatives><mixed-citation xml:lang="ru">Jaishankar M., Tseten T., Anbalagan N., Mathew B. B., Beeregowda K. N. Toxicity, mechanism and health effects of some heavy metals. Interdisciplinary Toxicology. 2014;7(2):60–72. DOI: 10.2478/intox-2014-0009.</mixed-citation><mixed-citation xml:lang="en">Jaishankar M., Tseten T., Anbalagan N., Mathew B. B., Beeregowda K. N. Toxicity, mechanism and health effects of some heavy metals. Interdisciplinary Toxicology. 2014;7(2):60–72. DOI: 10.2478/intox-2014-0009.</mixed-citation></citation-alternatives></ref><ref id="cit5"><label>5</label><citation-alternatives><mixed-citation xml:lang="ru">Balali-Mood M., Naseri K., Tahergorabi Z., Khazdair M. R., Sadeghi M. Toxic Mechanisms of Five Heavy Metals: Mercury, Lead, Chromium, Cadmium, and Arsenic. Frontiers in Pharmacology. 2021;12. DOI: 10.3389/fphar.2021.643972.</mixed-citation><mixed-citation xml:lang="en">Balali-Mood M., Naseri K., Tahergorabi Z., Khazdair M. R., Sadeghi M. Toxic Mechanisms of Five Heavy Metals: Mercury, Lead, Chromium, Cadmium, and Arsenic. Frontiers in Pharmacology. 2021;12. DOI: 10.3389/fphar.2021.643972.</mixed-citation></citation-alternatives></ref><ref id="cit6"><label>6</label><citation-alternatives><mixed-citation xml:lang="ru">Kushwaha P. Metallic Impurities in Pharmaceuticals: An Overview. Current Pharmaceutical Analysis. 2021;17(8):960–968. DOI: 10.2174/1573412916999200711151147.</mixed-citation><mixed-citation xml:lang="en">Kushwaha P. Metallic Impurities in Pharmaceuticals: An Overview. Current Pharmaceutical Analysis. 2021;17(8):960–968. DOI: 10.2174/1573412916999200711151147.</mixed-citation></citation-alternatives></ref><ref id="cit7"><label>7</label><citation-alternatives><mixed-citation xml:lang="ru">Robert T. Elemental Impurities in Pharmaceuticals. Measuring Elemental Impurities in Pharmaceuticals. 2018;29:11–29. DOI: 10.1201/b21952-2.</mixed-citation><mixed-citation xml:lang="en">Robert T. Elemental Impurities in Pharmaceuticals. Measuring Elemental Impurities in Pharmaceuticals. 2018;29:11–29. DOI: 10.1201/b21952-2.</mixed-citation></citation-alternatives></ref><ref id="cit8"><label>8</label><citation-alternatives><mixed-citation xml:lang="ru">Balaram V. Recent advances in the determination of elemental impurities in pharmaceuticals – Status, challenges and moving frontiers. TrAC Trends in Analytical Chemistry. 2016;80:83–95. DOI: 10.1016/j.trac.2016.02.001.</mixed-citation><mixed-citation xml:lang="en">Balaram V. Recent advances in the determination of elemental impurities in pharmaceuticals – Status, challenges and moving frontiers. TrAC Trends in Analytical Chemistry. 2016;80:83–95. DOI: 10.1016/j.trac.2016.02.001.</mixed-citation></citation-alternatives></ref><ref id="cit9"><label>9</label><citation-alternatives><mixed-citation xml:lang="ru">Aleluia A. C. M., de Souza Nascimento M., dos Santos A. M. P., dos Santos W. N.cL., de Freitas Santos Júnior A., Costa Ferreira S. L. Analytical approach of elemental impurities in pharmaceutical products: A worldwide review. Spectrochimica Acta Part B: Atomic Spectroscopy. 2023;205:106689. DOI: 10.1016/j.sab.2023.106689.</mixed-citation><mixed-citation xml:lang="en">Aleluia A. C. M., de Souza Nascimento M., dos Santos A. M. P., dos Santos W. N.cL., de Freitas Santos Júnior A., Costa Ferreira S. L. Analytical approach of elemental impurities in pharmaceutical products: A worldwide review. Spectrochimica Acta Part B: Atomic Spectroscopy. 2023;205:106689. DOI: 10.1016/j.sab.2023.106689.</mixed-citation></citation-alternatives></ref><ref id="cit10"><label>10</label><citation-alternatives><mixed-citation xml:lang="ru">Rekhi H., Kaur R., Rani S., Malik A. K., Kabir A., Furton K. G. Direct Rapid Determination of Trace Aluminum in Various Water Samples with Quercetin by Reverse Phase High-Performance Liquid Chromatography Based on Fabric Phase Sorptive Extraction Technique. Journal of Chromatographic Science. 2018;56(5):452–460. DOI: 10.1093/chromsci/bmy015.</mixed-citation><mixed-citation xml:lang="en">Rekhi H., Kaur R., Rani S., Malik A. K., Kabir A., Furton K. G. Direct Rapid Determination of Trace Aluminum in Various Water Samples with Quercetin by Reverse Phase High-Performance Liquid Chromatography Based on Fabric Phase Sorptive Extraction Technique. Journal of Chromatographic Science. 2018;56(5):452–460. DOI: 10.1093/chromsci/bmy015.</mixed-citation></citation-alternatives></ref><ref id="cit11"><label>11</label><citation-alternatives><mixed-citation xml:lang="ru">Giordano R., Ciaralli L., Ciprotti M., Camoni I., Costantini S. Applicability of High-Performance Ion Chromatography (HPIC) to the Determination of Fosetyl-Aluminum in Commercial Formulations. Microchemical Journal. 1995;52(1):68–76. DOI: 10.1006/mchj.1995.1068.</mixed-citation><mixed-citation xml:lang="en">Giordano R., Ciaralli L., Ciprotti M., Camoni I., Costantini S. Applicability of High-Performance Ion Chromatography (HPIC) to the Determination of Fosetyl-Aluminum in Commercial Formulations. Microchemical Journal. 1995;52(1):68–76. DOI: 10.1006/mchj.1995.1068.</mixed-citation></citation-alternatives></ref><ref id="cit12"><label>12</label><citation-alternatives><mixed-citation xml:lang="ru">Tria J., Haddad P. R., Nesterenko P. N. Determination of aluminium using high performance chelation ion chromatography. Journal of Separation Science. 2008;31(12):2231–2238. DOI: 10.1002/jssc.200800046.</mixed-citation><mixed-citation xml:lang="en">Tria J., Haddad P. R., Nesterenko P. N. Determination of aluminium using high performance chelation ion chromatography. Journal of Separation Science. 2008;31(12):2231–2238. DOI: 10.1002/jssc.200800046.</mixed-citation></citation-alternatives></ref><ref id="cit13"><label>13</label><citation-alternatives><mixed-citation xml:lang="ru">Arvand M., Kermanian M., Zanjanchi M. A. Direct determination of aluminium in foods and pharmaceutical preparations by potentiometry using an AlMCM-41 modified polymeric membrane sensor. Electrochimica Acta. 2010;55(23):6946–6952. DOI: 10.1016/j.electacta.2010.06.083.</mixed-citation><mixed-citation xml:lang="en">Arvand M., Kermanian M., Zanjanchi M. A. Direct determination of aluminium in foods and pharmaceutical preparations by potentiometry using an AlMCM-41 modified polymeric membrane sensor. Electrochimica Acta. 2010;55(23):6946–6952. DOI: 10.1016/j.electacta.2010.06.083.</mixed-citation></citation-alternatives></ref><ref id="cit14"><label>14</label><citation-alternatives><mixed-citation xml:lang="ru">Kasprzak M. M., Erxleben A., Ochocki J. Properties and applications of flavonoid metal complexes. RSC Advances. 2015;5(57):45853–45877. DOI: 10.1039/c5ra05069c.</mixed-citation><mixed-citation xml:lang="en">Kasprzak M. M., Erxleben A., Ochocki J. Properties and applications of flavonoid metal complexes. RSC Advances. 2015;5(57):45853–45877. DOI: 10.1039/c5ra05069c.</mixed-citation></citation-alternatives></ref></ref-list><fn-group><fn fn-type="conflict"><p>The authors declare that there are no conflicts of interest present.</p></fn></fn-group></back></article>
