najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2024-15-5-683-692najo-140Research ArticleCHEMISTRY AND MATERIAL SCIENCEХИМИЯ И МАТЕРИАЛОВЕДЕНИЕPhysicochemical properties and biological activity of novel cerium oxide nanoparticles modified with pyrroloquinoline quinoneФизико-химические характеристики и биологическая активность новых наночастиц оксида церия, модифицированных пирролохинолинхинономhttps://orcid.org/0000-0002-1275-565XЗамятинаЕ. А.ZamyatinaElizaveta A.

Elizaveta A. Zamyatina 

Institutskaya str., 3, Pushchino, 142290

sonyoru162@gmail.comhttps://orcid.org/0000-0002-0910-7694ГорячеваО. А.GoryachevaOlga A.

Olga A. Goryacheva 

Astrakhanskaya 83, Saratov, 410012

olga.goryacheva.93@mail.ruhttps://orcid.org/0000-0002-0982-6349ПоповаН. Р.PopovaNelli R.

Nelli R. Popova

Institutskaya str., 3, Pushchino, 142290

nellipopovaran@gmail.comInstitute of Theoretical and Experimental Biophysics of the Russian Academy of SciencesRussian FederationSaratov State University named after N. G. Chernyshevsky, Chemistry InstituteRussian Federation202403062025155683692Copyright © Zamyatina E.A., Goryacheva O.A., Popova N.R., 20252025Замятина Е.А., Горячева О.А., Попова Н.Р.Zamyatina E.A., Goryacheva O.A., Popova N.R.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/140

Nanoscale cerium oxide (CeO2) is a bioavailable inorganic nanozyme exhibiting pronounced redox activity and capable of acting as a delivery system for bioactive compounds. We have synthesized and characterized novel CeO2 nanoparticles modified with pyrroloquinoline quinone (CeO2@PQQ). TEM analysis revealed the diameter of the CeO2@PQQ NPs to be approximately 4 nm, with a hydrodynamic diameter of 62 nm (DLS). Furthermore, the zeta potential was found to be −38 mV (ELS), and FTIR analysis confirmed the adsorption of PQQ on the surface of CeO2 NPs. The results demonstrated that CeO2@PQQ NPs exhibited no cytotoxic effects on L929 cells within the concentration range of 0.1 – 10 µM and did not adversely affect the mitochondrial function of the cells. It was demonstrated that CeO2@PQQ NPs exhibited protective effects against L929 cells when induced with oxidative stress (200 µM H2O2), leading to preservation of cell mitochondrial potential levels up to 76 % of control and cell viability up to 78 % before and after incubation with CeO2@PQQ NPs. The results indicate that CeO2@PQQ NPs can be regarded as a novel hybrid nanosystem that exhibits mitochondrial-directed control of oxidative stress.

Наноразмерный оксид церия (CeO2) является биодоступным неорганическим нанозимом, проявляющим выраженную окислительно-восстановительную активность и способным выступать в роли системы доставки биоактивных соединений. Нами были синтезированы и охарактеризованы новые наночастицы (NPs) CeO2, модифицированные пирролохинолинхиноном (PQQ). Показано, что CeO2@PQQ NPs имеют размер до 4 нм (ТЭМ), гидродинамический диаметр составил 62 нм (DLS), дзета-потенциал -38 мВ, PQQ адсорбируется на поверхности CeO2 NPs (FTIR). Установлено, что в диапазоне концентраций 0,1-10 мкМ CeO2@PQQ NPs не оказывают цитотоксического эффекта на культуру клеток фибробластов мыши (L929), а также не оказывают негативного влияния на митохондриальную функцию L929. Было выявлено, что при индукции окислительного стресса (200 мкМ H2O2) CeO2@PQQ NPs проявляют защитное действие в отношении L929 в концентрациях 0,1-10 мкМ, приводя к сохранению уровня митохондриального потенциала клеток до 76% от контроля и жизнеспособности клеток до 78% до и после добавления наночастиц. Результаты работы позволяют рассматривать CeO2@PQQ NPs в качестве новой гибридной наносистемы для митохондриально-направленной борьбы с окислительным стрессом.

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The authors declare that there are no conflicts of interest present.