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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">sechenov</journal-id><journal-title-group><journal-title xml:lang="en">Sechenov Medical Journal</journal-title><trans-title-group xml:lang="ru"><trans-title>Сеченовский вестник</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2218-7332</issn><issn pub-type="epub">2658-3348</issn><publisher><publisher-name>Сеченовский Университет</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.47093/2218-7332.2022.338.06</article-id><article-id custom-type="elpub" pub-id-type="custom">sechenov-423</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>BIOMEDICINE</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>БИОМЕДИЦИНА</subject></subj-group></article-categories><title-group><article-title>Lifetime imaging of the discrete nanophosphors in biological systems</article-title><trans-title-group xml:lang="ru"><trans-title>Визуализация дискретных нанофосфоров в биологических системах с учетом времени жизни флуоресценции</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-4490-4867</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Звягинцев</surname><given-names>А. О.</given-names></name><name name-style="western" xml:lang="en"><surname>Zvyagintcev</surname><given-names>A. O.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Звягинцев Артём Олегович, студент-стажер</p><p>Ленинский проспект, д. 59, г. Москва, 119333</p></bio><bio xml:lang="en"><p>Artyom O. Zviagintcev, student intern</p><p>59, Leninsky Prospekt, Moscow, 119333</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/0000-0003-0333-5095</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Юдинцев</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Yudintsev</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Юдинцев Андрей Владимирович, канд. физ.-мат. наук, доцент, преподаватель кафедры биофизики Института биологии и биомедицины</p><p>пр. Гагарина, д. 23, корп. 2, Нижний Новгород, 603022</p></bio><bio xml:lang="en"><p>Andrey V. Yudintsev, Cand. of Sci. (Phys. and Math.), Associate Professor, Lecturer of the Department of Biophysics, Institute of Biology and Biomedicine</p><p>23, bld. 2, Prospekt Gagarina, Nizhny Novgorod, 603022</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/0000-0003-2852-2102</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Малеки</surname><given-names>А.</given-names></name><name name-style="western" xml:lang="en"><surname>Maleki</surname><given-names>A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Малеки Алиреза, аспирант-исследователь факультета физики и астрономии</p><p>Балаклавская дорога, Норт-Райд, Новый Южный Уэльс, Сидней, 2109</p></bio><bio xml:lang="en"><p>Alireza Maleki, Postdoctoral Research Fellow, Department of Physics and Astronomy</p><p>Balaclava Road, North Ryde NSW 2109, Sydney</p></bio><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3726-5577</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Воденеев</surname><given-names>В. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Vodeneev</surname><given-names>V. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Воденеев Владимир Анатольевич, д-р биол. наук, доцент, заведующий кафедрой биофизики Института биологии и биомедицины</p><p>пр. Гагарина, д. 23, корп. 2, Нижний Новгород, 603022</p></bio><bio xml:lang="en"><p>Vladimir A. Vodeneev, Dr. of Sci. (Biology), Associate Professor, Head of the Department of Biophysics, Institute of Biology and Biomedicine</p><p>23, bld. 2, Prospekt Gagarina, Nizhny Novgorod, 603022</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/0000-0001-8799-2257</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Звягин</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Zvyagin</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Звягин Андрей Васильевич, д-р физ.-мат. наук, Институт биологии и биомедицины; группа биомедицинской физики, руководитель факультета науки и техники Университета Маккуори</p><p>пр. Гагарина, д. 23, корп. 2, Нижний Новгород, 603022, Россия</p><p>Балаклавская дорога, Норт-Райд, Новый Южный Уэльс, Сидней, 2109, Австралия</p><p>Тел.: +7 (909) 924 91 16</p></bio><bio xml:lang="en"><p>Andrei V. Zvyagin, Dr. of Sci. (Physics and Mathematics), Institute of Biology and Biomedicine; Biomedical Physics Group, Head Faculty of Science and Engineering, Macquarie University</p><p>23, bld. 2, Prospekt Gagarina, Nizhny Novgorod, 603022, Russia</p><p>Balaclava Road, North Ryde NSW 2109, Sydney, Australia</p><p>Tel.: +7 (909) 924 91</p></bio><email xlink:type="simple">andrei.zvyagin@mq.edu.au</email><xref ref-type="aff" rid="aff-4"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФНИЦ «Кристаллография и фотоника» Российской академии наук</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Federal Scientific Research Centre “Crystallography and Photonics” of Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ФГАУ ВО «Национальный исследовательский Нижегородский государственный университет им. Н.И. Лобачевского» (ННГУ)</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Lobachevsky Nizhny Novgorod State University</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Университет Маккуори</institution><country>Австралия</country></aff><aff xml:lang="en"><institution>Macquarie University</institution><country>Australia</country></aff></aff-alternatives><aff-alternatives id="aff-4"><aff xml:lang="ru"><institution>ФГАУ ВО «Национальный исследовательский Нижегородский государственный университет им. Н.И. Лобачевского» (ННГУ); Университет Маккуори</institution><country>Австралия</country></aff><aff xml:lang="en"><institution>Lobachevsky Nizhny Novgorod State University; Macquarie University</institution><country>Australia</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>25</day><month>10</month><year>2021</year></pub-date><volume>13</volume><issue>1</issue><fpage>43</fpage><lpage>54</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Zvyagintcev A.O., Yudintsev A.V., Maleki A., Vodeneev V.A., Zvyagin A.V., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Звягинцев А.О., Юдинцев А.В., Малеки А., Воденеев В.А., Звягин А.В.</copyright-holder><copyright-holder xml:lang="en">Zvyagintcev A.O., Yudintsev A.V., Maleki A., Vodeneev V.A., Zvyagin A.V.</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.sechenovmedj.com/jour/article/view/423">https://www.sechenovmedj.com/jour/article/view/423</self-uri><abstract><p>The aim. Demonstrate a novel modality of laser-scanning multiphoton microscopy suitable for rapid acquisition of images of samples labelled with phosphorescent materials characterised by long emission lifetime measured in microseconds. The reported microscopy represents an advancement over the existing laser-scanning modalities, where the acquisition of images of phosphorescent materials takes unpractically long time.Materials and methods. The reported method is based on rapid scanning of the focussed excitation beam across a sample while continuously recording the photoluminescent (PL) signal. The resultant images of discrete phosphorescent nanoparticles appeared blurred. The diffraction-limited image was reconstructed by using a deconvolution algorithm, where the PL lifetime was the key input parameter. To test the method, two types of upconversion nanoparticles (UCNP) were synthesised, NaYF4:Yb3+:Er3+/NaYF4 (E-UCNP), β-NaYF4:Yb3+, Tm3+/NaYF4 (T-UCNP) and used to test a possibility of demultiplexing the two types of UCNPs ex vivo taken up in the mouse liver.Results. The resultant images of E-UCNP, T-UCNP on the background of the liver were fully reconstructed and exhibited the enhanced signal-to-noise ratio. Besides, the method allowed rapid (at the scale of seconds) acquisition of the UCNP PL lifetime and clear discrimination of the two types of UCNPs.Conclusion. We demonstrated a new approach for rapid PL image acquisition of samples containing PL materials, such as biological specimens labelled with discrete UCNPs. Blurred images were shown to be reconstructed at the post-processing stage by applying a deconvolution procedure. This enabled demonstration of multiplexing/demultiplexing using lifetime imaging mode, where the lifetime was engineered by the UCNP synthesis and reconstructed during multiphoton image acquisition using the deconvolution algorithm. The power of this method was demonstrated by the identification of two types of UCNPs accumulated in the liver of a laboratory animal. We believe that the demonstrated method can be useful for rapid lifetime imaging where several molecular specific labelling agents are required.</p></abstract><trans-abstract xml:lang="ru"><p>Цель. Продемонстрировать новый метод лазерной сканирующей многофотонной микроскопии, подходящий для быстрого получения изображений образцов, меченных фосфоресцирующими материалами, характеризующихся длительным временем жизни излучения, измеряемым в микросекундах. Представленная микроскопия представляет собой прогресс по сравнению с существующими методами лазерного сканирования, в которых получение изображений фосфоресцирующих материалов занимает непрактично долгое время.Материал и методы. Описанный метод основан на быстром сканировании сфокусированного луча возбуждения по образцу при непрерывной регистрации фотолюминесцентного (PL) сигнала. Полученные изображения дискретных фосфоресцирующих наночастиц выглядели размытыми. Изображение с дифракционным разрешением было восстановлено с использованием алгоритма деконволюции, где время жизни PL было ключевым входным параметром. Для тестирования метода были синтезированы два типа апконверсионных частиц (UCNP): NaYF4:Yb3+:Er3+/ NaYF4 (E-UCNP), β-NaYF4:Yb3+,Tm3+/NaYF4 (T-UCNP) и использованы для проверки возможности демультиплексирования двух типов UCNP ex vivo, доставленных в печень лабораторной мыши.Результаты. Полученные изображения E-UCNP, T-UCNP на фоне печени были полностью реконструированы и показали улучшенное отношение сигнал/шум. Кроме того, метод позволял быстро (в масштабе секунд) получать время жизни PL UCNP и четко различать два типа UCNP.Заключение. Мы продемонстрировали новый подход для быстрого получения изображений PL-образцов, содержащих флуоресцирующие вещества, например биологических образцов, меченных дискретными UCNP. Было показано, что размытые изображения восстанавливаются на этапе постобработки путем применения процедуры деконволюции. Это позволило продемонстрировать мультиплексирование/демультиплексирование в режиме визуализации времени жизни, где время жизни определялось синтезом UCNP и восстанавливалось во время получения многофотонного изображения с помощью алгоритма деконволюции. Возможности этого метода были продемонстрированы на примере идентификации двух типов UCNP, накопленных в печени лабораторного животного. Мы считаем, что продемонстрированный метод может быть полезен для быстрой прижизненной визуализации, когда требуется несколько молекулярно-специфических меченых агентов.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>биофотоника</kwd><kwd>прижизненная визуализация</kwd><kwd>фосфорсодержащие материалы</kwd><kwd>фотолюминесценция наночастиц с восходящей конверсией</kwd><kwd>многофотонная микроскопия</kwd></kwd-group><kwd-group xml:lang="en"><kwd>biophotonics</kwd><kwd>lifetime imaging</kwd><kwd>phosphorous materials</kwd><kwd>upconversion nanoparticles photoluminescence</kwd><kwd>multiphoton microscopy</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Авторы выражают благодарность за финансовую поддержку Российскому фонду фундаментальных исследований (РФФИ), грант № 20-04-00182.</funding-statement><funding-statement xml:lang="en">The authors wish to acknowledge financial support from the Russian Foundation of Basic Research (RFBR), grant No 20-04-00182.</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">Moerner W.E. 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