2026-09-06T08:04:36Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/119962026-09-05T00:05:22Zcom_10259_4323com_10259_5086com_10259_2604col_10259_4330

Polarity-Driven Selective Adsorption of Quercetin on Kaolinite: An Integrated DFT and Monte Carlo Study Ayad, Abdelilah El Himri, Abdelouahad Harrou, Achraf Benali, Mohammed Dira, Abdelouassia Aparicio Martínez, Santiago Gutiérrez Vega, Alberto Soldera, Armand Gharibi, Elkhadir Clay Flavonoid Surface engineering Nanocarrier design Food Encapsulation Caolinita Kaolinite Quercetin’s therapeutic potential is limited by its poor water solubility and rapid degradation. Natural clay minerals such as kaolinite present sustainable platforms for drug delivery, yet the molecular mechanisms of drug encapsulation are not fully understood. Specifically, the role of kaolinite’s structural polarity, its hydrophilic aluminol (001) and hydrophobic siloxane (00-1) basal surfaces, in selective drug adsorption remains unexplored. This study combines Monte Carlo sampling and Density Functional Theory (DFT) to provide the first quantitative, atomistic comparison of quercetin adsorption on both kaolinite surfaces. The results demonstrate a pronounced polarity-driven selectivity. Strong, exothermic adsorption (−206.65 kJ mol−1) occurs on the hydrophilic (001) surface, stabilized by a network of five hydrogen bonds. In contrast, the hydrophobic (00-1) surface exhibits significantly weaker sorption (−147.16 kJ mol−1), dominated by van derWaals interactions. Charge-transfer analysis shows that the hydrophilic (001) surface exhibits a net charge transfer of −0.198 e, approximately 2.4 times greater than that of the hydrophobic (00-1) surface (−0.083 e), consistent with differential electron density maps and partial density of states. By linking hydrogen bonding and charge transfer to adsorption energy, these results elucidate how surface polarity dictates drug encapsulation. This work establishes a predictive framework for designing kaolinite-based nanocarriers with optimized stability, bioavailability, and controlled release, guiding the development of sustainable drug delivery systems. It is noted that this DFT study models adsorption at 0 K using periodic slab models in a vacuum. AS gratefully acknowledges the Natural Sciences and Engineering Research Council (NSERC) of Canada (Grant no. RGPIN-2024-05202). A. Ayad gratefully acknowledges the CNRST (Centre National pour la Recherche Scientifique et Technique) in Morocco for the PhD scholarship. Authors gratefully acknowledges Eleni Gianni, Applied Mineralogy|Molecular Simulations, Centre for Research and Technology Hellas. 2026-09-04T07:43:15Z 2026-09-04T07:43:15Z 2026-01 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion https://hdl.handle.net/10259/11996 10.3390/MA19020368 1996-1944 eng Materials. 2026, V. 19, n. 2, art. 368 https://doi.org/10.3390/ma19020368 Atribución 4.0 Internacional http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess application/pdf MDPI https://riubu.ubu.es/bitstream/10259/11996/4/Ayad-Materials_2026.pdf.jpg Hispana TEXT http://creativecommons.org/licenses/by/4.0/ RIUBU. Repositorio Institucional de la Universidad de Burgos https://hdl.handle.net/10259/11996