najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2021-12-5-612-622najo-543Research ArticleCHEMISTRY AND MATERIAL SCIENCEХИМИЯ И МАТЕРИАЛОВЕДЕНИЕStructural and energetic analysis of cyclic peptide-gold nano-drug delivery system: a DFT studyСтруктурный и энергетический анализ циклической системы доставки нанолекарств пептид-золото: исследование DFTKhoshbayanB.KhoshbayanB.

Mashhad

bahareh.khoshbayan@gmail.comMorsaliA.MorsaliA.

Mashhad

almorsali@yahoo.comBozorgmehrM. R.BozorgmehrM. R.

Mashhad

mr_bozorgmehr@yahoo.comBeyramabadiS. A.BeyramabadS. A.

Mashhad

abeyramabadi@gmail.comDepartment of Chemistry, Mashhad Branch, Islamic Azad UniversityIslamic Republic of Iran202105082025125612622Copyright © Khoshbayan B., Morsali A., Bozorgmehr M.R., Beyramabad S.A., 20252025Khoshbayan B., Morsali A., Bozorgmehr M.R., Beyramabadi S.A.Khoshbayan B., Morsali A., Bozorgmehr M.R., Beyramabad S.A.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/543

By applying cyclooctaglycine model for cyclic peptide (CP) and cluster Au6 model for gold nanoparticles (GN), seven different configurations of cyclic peptide-gold nanoparticles (CPGN) with 5-fluorouracil (FU) were investigated. Binding energies, quantum molecular descriptors, and solvation energies in the aqueous solution and gas phase were studied at the density functional level of M06-2X/6-31g(d, p). Solvation energies indicate that the solubility of FU increases in CPGN/FU1-7. This subject is considered a key factor for drug transfer, so CPGNs can be used as an appropriate drug delivery system. The large negative values of calculated binding energies show the stability of CPGN/FU1-7 structures, and quantum molecular descriptors, such as electrophilicity (ω) and global hardness (η) indicate that the reactivity of FU in CPGN/FU1-7 structures increases. AIM calculations for all structures also show that intermolecular hydrogen bonding and Au-drug interactions play an important role for this drug delivery system.

Применяя модель циклооктаглицина для циклического пептида (CP) и модель кластера Au6 для наночастиц золота (GN), исследовали семь различных конфигураций циклических систем пептид-наночастиц золота (ЦПГН) с 5-фторурацилом (FU). Энергии связи, квантовые молекулярные дескрипторы и энергии сольватации в водном растворе и газовой фазе изучались на уровне функционала плотности M06-2X/6-31g(d, p). Энергии сольватации указывают на то, что растворимость FU увеличивается в CPGN/FU1-7. Этот субъект считается ключевым фактором для передачи лекарств, поэтому CPGN можно использовать в качестве подходящей системы доставки лекарств. Большие отрицательные значения рассчитанных энергий связи показывают стабильность структур CPGN/FU1-7, а квантовые молекулярные дескрипторы, такие как электрофильность (ω) и глобальная жесткость (η), указывают на то, что реакционная способность FU в структурах CPGN/FU1-7 увеличивается. Расчеты AIM для всех структур также показывают, что межмолекулярные водородные связи и взаимодействия Au с лекарствами играют важную роль для этой системы доставки лекарств.

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