<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-09-06T11:10:12Z</responseDate><request verb="GetRecord" identifier="oai:riubu.ubu.es:10259/11996" metadataPrefix="etdms">https://riubu.ubu.es/oai/request</request><GetRecord><record><header><identifier>oai:riubu.ubu.es:10259/11996</identifier><datestamp>2026-09-05T00:05:22Z</datestamp><setSpec>com_10259_4323</setSpec><setSpec>com_10259_5086</setSpec><setSpec>com_10259_2604</setSpec><setSpec>col_10259_4330</setSpec></header><metadata><thesis xmlns="http://www.ndltd.org/standards/metadata/etdms/1.0/" xmlns:doc="http://www.lyncode.com/xoai" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.ndltd.org/standards/metadata/etdms/1.0/ http://www.ndltd.org/standards/metadata/etdms/1.0/etdms.xsd">
<title>Polarity-Driven Selective Adsorption of Quercetin on Kaolinite: An Integrated DFT and Monte Carlo Study</title>
<creator>Ayad, Abdelilah</creator>
<creator>El Himri, Abdelouahad</creator>
<creator>Harrou, Achraf</creator>
<creator>Benali, Mohammed</creator>
<creator>Dira, Abdelouassia</creator>
<creator>Aparicio Martínez, Santiago</creator>
<creator>Gutiérrez Vega, Alberto</creator>
<creator>Soldera, Armand</creator>
<creator>Gharibi, Elkhadir</creator>
<subject>Clay</subject>
<subject>Flavonoid</subject>
<subject>Surface engineering</subject>
<subject>Nanocarrier design</subject>
<subject>Food</subject>
<subject>Encapsulation</subject>
<description>Quercetin’s therapeutic potential is limited by its poor water solubility and rapid degradation.&#xd;
Natural clay minerals such as kaolinite present sustainable platforms for drug&#xd;
delivery, yet the molecular mechanisms of drug encapsulation are not fully understood.&#xd;
Specifically, the role of kaolinite’s structural polarity, its hydrophilic aluminol (001) and hydrophobic&#xd;
siloxane (00-1) basal surfaces, in selective drug adsorption remains unexplored.&#xd;
This study combines Monte Carlo sampling and Density Functional Theory (DFT) to provide&#xd;
the first quantitative, atomistic comparison of quercetin adsorption on both kaolinite&#xd;
surfaces. The results demonstrate a pronounced polarity-driven selectivity. Strong, exothermic&#xd;
adsorption (−206.65 kJ mol−1) occurs on the hydrophilic (001) surface, stabilized by&#xd;
a network of five hydrogen bonds. In contrast, the hydrophobic (00-1) surface exhibits&#xd;
significantly weaker sorption (−147.16 kJ mol−1), dominated by van derWaals interactions.&#xd;
Charge-transfer analysis shows that the hydrophilic (001) surface exhibits a net charge&#xd;
transfer of −0.198 e, approximately 2.4 times greater than that of the hydrophobic (00-1)&#xd;
surface (−0.083 e), consistent with differential electron density maps and partial density&#xd;
of states. By linking hydrogen bonding and charge transfer to adsorption energy, these&#xd;
results elucidate how surface polarity dictates drug encapsulation. This work establishes a&#xd;
predictive framework for designing kaolinite-based nanocarriers with optimized stability,&#xd;
bioavailability, and controlled release, guiding the development of sustainable drug delivery&#xd;
systems. It is noted that this DFT study models adsorption at 0 K using periodic slab&#xd;
models in a vacuum.</description>
<date>2026-09-04</date>
<date>2026-09-04</date>
<date>2026-01</date>
<type>info:eu-repo/semantics/article</type>
<identifier>https://hdl.handle.net/10259/11996</identifier>
<identifier>10.3390/MA19020368</identifier>
<identifier>1996-1944</identifier>
<language>eng</language>
<relation>Materials. 2026, V. 19, n. 2, art. 368</relation>
<relation>https://doi.org/10.3390/ma19020368</relation>
<rights>http://creativecommons.org/licenses/by/4.0/</rights>
<rights>info:eu-repo/semantics/openAccess</rights>
<rights>Atribución 4.0 Internacional</rights>
<publisher>MDPI</publisher>
</thesis></metadata></record></GetRecord></OAI-PMH>