The L.N. Gumilyov Eurasian National University will defend the thesis for the degree of Doctor of Philosophy (PhD) by Zhumabayeva Gulstan on the topic «Development of new composite materials by modifying porous inorganic compounds with heterocycles based on glycolurils» under the educational program «8D05306 – Chemistry».
The dissertation was carried out at the «Chemistry education department» of L.N. Gumilyov Eurasian National University.
The language of defense is kazakh
Official reviewers:
Bektenov Nesiphan Abzhaparovich – Doctor of Chemical Sciences, Professor, Academician of the National Academy of Sciences of the Republic of Kazakhstan, Non-Profit Joint-Stock Company “Abai Kazakh National Pedagogical University” (Almaty, Republic of Kazakhstan);
Appazov Nurbol Orynbasaruly – Candidate of chemical sciences, Professor, Non-Profit Joint-Stock Company “Korkyt Ata Kyzylorda State University” (Kyzylorda, Republic of Kazakhstan).
Temporary members of the Dissertation Council:
Mataev Mukhametkali Musagalievich – Doctor of Chemical Sciences, Professor, Non-Profit Joint-Stock Company “Kazakh National Women's Teacher Training University” (Almaty, Republic of Kazakhstan);
Festa Aleksey Alekseevich – Candidate of chemical sciences, Associate Professor, Patrice Lumumba Peoples' Friendship University of Russia (Moscow, Russian Federation);
Zhumagaliyeva Shinar Nurlanovna – Doctor of Chemical Sciences, Professor, Non-Profit Joint-Stock Company “Al-Farabi Kazakh National University” (Almaty, Republic of Kazakhstan).
Scientific advisors:
Erkasov Rakhmetulla Sharapidenovich – Doctor of Chemical Sciences, Professor, Department of Chemistry, L.N. Gumilyov Eurasian National University (Astana, Republic of Kazakhstan);
Bakibaev Abdigali Abdimanapovich – Doctor of Chemical Sciences, Professor, National Research Tomsk State University (Tomsk, Russian Federation).
The defense will take place on August 27, 2026, at 02:00 PM in the Dissertation Council for the training direction «8D053 – Physical and chemical sciences» in the educational program «8D05306 – Chemistry» of L.N. Gumilyov Eurasian National University. The Dissertation Council meeting will be held offline and online.
Link: https://clck.ru/3UT3G8
Address: K. Satpayev Street, 2, Room: 302., Astana, Republic of Kazakhstan.
Abstract (English): ANNOTATION on the dissertation of Zhumabaeva Gulstan Karshygaevna on the topic «Development of new composite materials by modifying porous inorganic compounds with heterocycles based on glycolurils» submitted for the degree of Doctor of Philosophy (PhD) in the educational program «8D05306 – Chemistry» General Description of the Dissertation Research. This dissertation is devoted to investigating the physicochemical properties of novel composite materials based on diatomite, hydroxyapatite, mesoporous bioactive glasses (MBGs), and other porous inorganic materials through surface modification with bioactive organic compounds of both synthetic and natural origin. Chloramphenicol, tetrahydroxymethylglycoluril (THMGU), betulin, and cucurbit[n]urils (CB[6], CB[7], and CB[8]) were employed as surface-modifying agents. The synthesised materials were characterised using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Furthermore, the hemolytic activity, plasma protein adsorption, and antibacterial properties of the obtained biocomposites were systematically evaluated. The dissertation is presented as a series of scientific publications authored by the doctoral candidate in accordance with Clause 5-1 of the Rules for Awarding Academic Degrees, approved by Order No. 127 of the Minister of Education and Science of the Republic of Kazakhstan, dated 31 March 2011 (registered in the State Register of Regulatory Legal Acts under No. 6951), as amended by Order No. 4 dated 6 January 2025. The dissertation also complies with the requirements of Order No. 98 of the Minister of Education and Science of the Republic of Kazakhstan, dated 9 March 2021, as amended by Order No. 7 of the Acting Minister of Science and Higher Education of the Republic of Kazakhstan, dated 9 January 2023. Research Significance. Advanced composite materials play an increasingly important role in medicine, catalysis, sensing technologies, environmental protection, and the development of functional coatings. Among these, porous inorganic materials such as hydroxyapatite, diatomite, and mesoporous bioactive glasses (MBGs) have attracted considerable attention for their high specific surface area, excellent mechanical strength, chemical stability, and outstanding biocompatibility, making them highly promising for biomedical applications. In recent years, there has been growing emphasis on the surface functionalisation of porous materials by incorporating biologically active compounds, particularly macrocyclic molecules. However, each material has inherent limitations. Hydroxyapatite requires surface modification to enhance cell adhesion and achieve controlled biodegradation. Diatomite requires functionalisation because of its chemical inertness, while the functional performance of mesoporous bioactive glasses depends not only on their physicochemical characteristics but also on the morphology of their porous network. A particularly promising strategy involves chemically modifying these substances with glycoluril-based organic macrocycles. Owing to their exceptional molecular recognition capability, ability to form stable host–guest complexes, and capacity to regulate surface properties, these compounds significantly enhance the adsorption, catalytic, mechanical, and biomedical performance of targeted composite materials. Betulin (BET), a pentacyclic triterpenoid isolated from birch bark, was selected as a natural model compound. Betulin and its derivatives exhibit a broad spectrum of biological activities, including wound-healing, antibacterial, antitumour, hypolipidaemic, hepatoprotective, and antiviral effects. Incorporating betulin is expected to mitigate the cytotoxic effects associated with antibacterial agents while enhancing the biological performance of the developed materials. The preparation of such composites required highly purified betulin. Aim of the Dissertation. The aim of this research was to develop porous inorganic composite materials based on hydroxyapatite, diatomite, and mesoporous bioactive glasses (MBGs) modified with glycoluril-derived heterocyclic compounds, namely tetrahydroxymethylglycoluril and cucurbit[6,7,8]urils, and to investigate their composition, structure, and physicochemical properties. Research Objectives. 1. To synthesise hydroxyapatite- and diatomite-based composite materials modified with tetrahydroxymethylglycoluril and investigate their physicochemical characteristics, including the morphology of the adsorbed layer, structural and spectroscopic properties, and biological performance. 2. To investigate the feasibility of obtaining highly purified betulin using a high-boiling hydrocarbon as a recrystallisation solvent. 3. To synthesise mesoporous bioactive glass-based composite materials modified with cucurbit[6,7,8]urils and investigate their physicochemical characteristics, including the morphology of the adsorbed layer and their structural and spectroscopic properties. Study object: Development of composite porous inorganic materials (hydroxyapatite, diatomite, and mesoporous bioactive glasses (MBGs)) modified with glycoluril-based heterocycles (tetrahydroxymethylglycoluril and cucurbit[n]urils), and study of their composition and properties. Research Methods: The dissertation utilised chemical methods: hydrolysis, acylation, and methylation. The following analytical methods were employed to characterize the substances and materials: IR-, UV-, 1H-, 13C- NMR, 2D- NMR – HMBC spectroscopy, mass spectrometry, high-performance liquid chromatography (HPLC), gas chromatography – mass spectrometry (GC–MS), elemental and X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD) for powder analysis, thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), and nitrogen sorption for porosity and specific surface area analysis. Biological activity (in vitro) was determined using the MTT test (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide). The interaction of CB[n] with the SiO2 surface was calculated using the molecular mechanics method. Scientific Novelty. 1. It was demonstrated for the first time that modification of hydroxyapatite- and diatomite-based scaffolds with tetrahydroxymethylglycoluril imparts pronounced antibacterial properties to the resulting composite materials. 2. A novel purification approach for betulin employing a high-boiling hydrocarbon solvent was demonstrated, enabling the production of betulin with a substantially higher degree of purity. Nonane (boiling point 151°C) was employed as the recrystallisation solvent and repeatedly refluxed with betulin until complete dissolution was achieved. 3. Mesoporous bioactive glass-based composite materials modified with cucurbit[6,7,8]urils were synthesized for the first time. The influence of different deposition techniques on the morphology of the adsorbed macrocyclic layer was systematically investigated. CB[6] was found to provide uniform pore coverage, reducing the specific surface area by 64% and the total pore volume by 52%. Furthermore, the interaction mechanism between cucurbit[6]uril and the MBG surface was elucidated by molecular mechanics simulations. Main Findings Submitted for Defence. 1. Hydroxyapatite- and diatomite-based composite materials modified with tetrahydroxymethylglycoluril exhibit pronounced antibacterial activity resulting from the chemical interaction between THMGU and the scaffold surface, accompanied by the formation of methanal. 2. The use of nonane as a recrystallisation solvent enables the preparation of betulin with a purity of up to 98%, making it suitable for subsequent chemical transformations without the need for additional purification. 3. A comprehensive investigation was conducted on bioactive glass-based composites modified with cucurbit[n]urils (CB[6], CB[7], and CB[8]). Their structural and physicochemical characteristics were evaluated using low-temperature nitrogen adsorption, simultaneous thermal analysis (STA), Fourier-transform infrared spectroscopy (FTIR), and molecular modelling of their interaction with the α-quartz surface. Practical Significance. This research advances the current understanding of the modification of porous biomedical materials using nitrogen-containing compounds. Fundamental insights have been obtained into the deposition of macrocyclic compounds onto porous inorganic substrates using different surface-modification techniques, contributing to the fields of chemistry and materials science. The results establish a scientific basis for the development of functional biomedical materials with precisely tailored properties through the combination of porous inorganic scaffolds and macrocyclic compounds. Furthermore, the experimentally established relationships between deposition technique and the morphology of the adsorbed macrocyclic layer may be extended to other classes of porous inorganic materials. Author's Contribution. The author's contributions include a comprehensive review of the relevant scientific literature, the design and execution of experimental and computational studies, the analysis and interpretation of experimental results, and the preparation of manuscripts for publication in peer-reviewed international scientific journals. Dissemination of Research Results. The results of this research were presented at the Kazakh–Uzbek Symposium "Modern Problems of Science" (Tashkent, Uzbekistan, 2024), the TASHKENT INTERNATIONAL CONGRESS ON MODERN SCIENCES–III, the XXI International Conference of Students, Postgraduates, and Young Scientists (Tomsk, Russia, 2024), as well as at the international scientific forums "Modern Scientific Method" (18–19 April 2024, Vienna, Austria) and "Theoretical Hypotheses and Empirical Results" (28–29 March 2024, Oslo, Norway). Publications. The principal findings of the dissertation are presented in eight published works, including four research articles published in journals ranked in the first and/or second quartiles (Q1/Q2) according to the Journal Citation Reports published by Clarivate Analytics, as well as four conference proceedings published in the abstracts of international scientific conferences. 1. Zhumabayeva, G.; Turebayeva, P.; Ukhov, A.; Fedorishin, D.; Gubankov, A.; Luchsheva, V.; Kurzina, I.; Bakibaev, A.; et al. Development of Novel Composite Biocompatible Materials by Surface Modification of Porous Inorganic Compounds Using Bambus[6]Uril. Materials 2023, 16, 7257. The doctoral candidate is the first author of this publication. According to the 2023 Journal Citation Reports, the journal Materials has an Impact Factor of 3.1. The journal is ranked Q3 in Physical Chemistry, Q2 in Materials Science, Multidisciplinary, Q1 in Metallurgy and Metallurgical Engineering, Q2 in Applied Physics, and Q2 in Physics, Condensed Matter. Its 2023 CiteScore is 5.8, with percentile rankings of 73 in Condensed Matter Physics and 67 in General Materials Science. The doctoral candidate was directly involved in conducting the experiments, processing and interpreting the experimental data. 2. Takibayeva, A.T.; Zhumabayeva, G.K.; Bakibaev, A.A.; Demets, O.V.; Lyapunova, M.V.; Mamaeva, E.A.; Yerkassov, R.S.; Kassenov, R.Z.; Ibrayev, M.K. Methods of Analysis and Identification of Betulin and Its Derivatives. Molecules 2023, 28, 5946. According to the 2023 Journal Citation Reports, Molecules has an Impact Factor of 4.2 and is classified as a Q2 journal in both Biochemistry and Molecular Biology and Chemistry, Multidisciplinary. The journal has a 2023 CiteScore of 7.4, with percentile rankings of 83 in Chemistry (Miscellaneous), 81 in Organic Chemistry, 80 in Physical and Theoretical Chemistry, 78 in Analytical Chemistry, 81 in Pharmaceutical Science, 73 in Drug Discovery, and 68 in Molecular Medicine. The doctoral candidate participated in the experimental work, data interpretation, and the preparation of the initial manuscript. 3. Kabieva, S.K.; Zhumanazarova, G.M.; Zhaslan, R.Z.; Zhumabayeva, G.; Ukhov, A.; Fedorishin, D.; Gubankov, A.; Tarikhov, F.; Yerkhan, O.; Kurzina, I.; Yerkassov, R.Sh.; Bakibaev, A. Obtaining New Biocompatible Composite Materials with Antibacterial Properties Based on Diatomite and Biologically Active Compounds. Molecules 2024, 29, 9720. According to the 2023 Journal Citation Reports, Molecules has an Impact Factor of 4.2 and is ranked Q2 in both Biochemistry and Molecular Biology and Chemistry, Multidisciplinary. The journal's 2023 CiteScore is 7.4. The doctoral candidate made a substantial contribution to the acquisition of experimental data, the analysis and interpretation of the results, and the preparation of the conclusions presented in the manuscript. 4. Zhumabayeva, G.; Bakibaev, A.; Ukhov, A.; Kurzina, I.; Mashayekhan, S.; Susid, M.; Khlebnikov, A.; Ryskaliyeva, R.; Yerkassov, R. Effect of Modification of Mesoporous Bioactive Glass with Cucurbit[n]urils (n = 6, 7, 8) on the Structural and Physicochemical Characteristics of Composite Biomaterials. Journal of Composites Science. 2026, 10(5), Article 255. The article is indexed in the Web of Science Core Collection. At the time of its publication in 2026, Journal of Composites Science had a 2024 Impact Factor of 3.7 and was ranked Q2 in the Materials Science, Composites category. At the time of the dissertation defense in 2026, the journal retained a 2024 Impact Factor of 3.7 and its Q2 ranking in Materials Science, Composites. The doctoral candidate is both the first author and the corresponding author of this publication and made a leading contribution to the research, data analysis, and manuscript preparation.
Conclusion of the Research Ethics Committee
Defense of the dissertation: https://youtu.be/62Xd0dPukWg?si=z4BqXm6Zh2vi5d7W
