Research Article

Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics

Volume: 2026 Number: 2 July 6, 2026

Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics

Abstract

Flavonoids are widely known for their significant biological activities; however, their poor aqueous solubility limits their practical applications. Recently, non-covalent loading methods using FDA-approved poly(ethylene glycol) (PEG) have been increasingly explored as simpler and more cost-effective alternatives to covalent conjugation strategies. In our previous work, the feasibility of non-covalent PEG–flavonoid systems was demonstrated as a promising approach to address these limitations. In the present study, non-covalent PEG systems having two structurally distinct flavonoids, quercetin and silibinin, were comparatively investigated to evaluate the combined effect of polymer molecular weight and flavonoid structure on physicochemical behavior. The prepared products were analyzed by UV–Vis spectroscopy for flavonoid content determination, along with FTIR spectroscopy to elucidate molecular interactions between PEG and flavonoids, thermogravimetric analysis (TGA), and particle size measurements. Despite the same loading conditions (1:20, w/w), post-washing behavior suggested a dependence on both flavonoid structure and PEG molecular weight. Silibinin-loaded PEG-2k systems exhibited higher flavonoid retention, smaller particle sizes, and improved thermal stability compared to PEG-5k counterparts suggesting relatively stronger non-covalent interactions within shorter PEG chains. In contrast, quercetin-loaded systems displayed similar flavonoid contents and thermal behavior across different PEG molecular weights, suggesting a lower sensitivity to polymer chain length. Overall, these findings demonstrate that non-covalent PEG–flavonoid systems are governed not only by nominal loading ratios but also by molecular structure and polymer architecture, providing a practical framework for the design of PEG-based carriers for poorly water-soluble bioactive compounds.

Keywords

Supporting Institution

Halic University

Project Number

HBAP604-IV-7

Ethical Statement

This study does not involve human participants or animal experiments. Therefore, ethical approval was not required.

Thanks

The author would like to thank Halic University (HBAP604-IV-7) for providing institutional support.

References

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Details

Primary Language

English

Subjects

Organic Chemistry (Other), Polymer Science and Technologies

Journal Section

Research Article

Publication Date

July 6, 2026

Submission Date

January 23, 2026

Acceptance Date

April 11, 2026

Published in Issue

Year 2026 Volume: 2026 Number: 2

APA
Aksakal, N. E. (2026). Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics. Journal of the Turkish Chemical Society Section A: Chemistry, 2026(2), 1-15. https://doi.org/10.18596/jotcsa.1870618
AMA
1.Aksakal NE. Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics. JOTCSA. 2026;2026(2):1-15. doi:10.18596/jotcsa.1870618
Chicago
Aksakal, Nuray Esra. 2026. “Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics”. Journal of the Turkish Chemical Society Section A: Chemistry 2026 (2): 1-15. https://doi.org/10.18596/jotcsa.1870618.
EndNote
Aksakal NE (July 1, 2026) Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics. Journal of the Turkish Chemical Society Section A: Chemistry 2026 2 1–15.
IEEE
[1]N. E. Aksakal, “Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics”, JOTCSA, vol. 2026, no. 2, pp. 1–15, July 2026, doi: 10.18596/jotcsa.1870618.
ISNAD
Aksakal, Nuray Esra. “Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics”. Journal of the Turkish Chemical Society Section A: Chemistry 2026/2 (July 1, 2026): 1-15. https://doi.org/10.18596/jotcsa.1870618.
JAMA
1.Aksakal NE. Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics. JOTCSA. 2026;2026:1–15.
MLA
Aksakal, Nuray Esra. “Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics”. Journal of the Turkish Chemical Society Section A: Chemistry, vol. 2026, no. 2, July 2026, pp. 1-15, doi:10.18596/jotcsa.1870618.
Vancouver
1.Nuray Esra Aksakal. Non-Covalent PEG Systems Incorporating Quercetin and Silibinin: A Comparative Evaluation of Polymer–Flavonoid Interactions and Physicochemical Characteristics. JOTCSA. 2026 Jul. 1;2026(2):1-15. doi:10.18596/jotcsa.1870618