{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T06:29:22Z","timestamp":1785738562872,"version":"3.56.0"},"reference-count":57,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,7]],"date-time":"2025-10-07T00:00:00Z","timestamp":1759795200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Background\/Objectives: The present work deals with the sol\u2013gel synthesis of hybrid materials based on a silica\u2013polyvinylpyrrolidone (Si-PVP) system. Methods: The nanohybrids have been prepared using an acidic catalyst at ambient temperature. Ibuprofen (IBP) was used as a model substance in the obtained model drug systems, while tetraethyl orthosilicate (TEOS) was used as a silica precursor. Poly(vinylpyrrolidone) (PVP) and IBP were introduced into the reaction mixture as solutions in ethanol using two different approaches: (i) a direct introduction of a drug solution into the reaction mixture during sol\u2013gel synthesis, and (ii) a solvent deposition technique. Results: XRD data provide evidence that IBP entrapped in the silica\u2013PVP network is in an amorphous state. By SEM it was revealed that in the adsorbate, the IBP particles possess an average particle size of about 20 \u03bcm. Based on the obtained IR and UV-Vis spectral results, the existence of hydrogen bonding of IBF with silica and PVP could be suggested. Solid-state NMR analysis allowed the identification of the presence of both crystalline-like and amorphous phases in the hybrid material prepared by the sol\u2013gel method, while it was demonstrated that in the adsorbate, the rigid crystalline dimeric structure of the drug has been preserved. Conclusions: The overall analysis of the structural characteristics of the two materials indicated that in the hybrid material obtained by the sol\u2013gel method, the interactions between the amorphous drug, PVP, and the silica matrix are more pronounced as compared to the adsorbate. An improvement of the drug\u2019s aqueous solubility as well of in vitro drug release profile (up to 8 h) was achieved, demonstrating the potential of the developed drug\u2013silica\u2013organic polymer nanohybrid as a promising drug delivery system.<\/jats:p>","DOI":"10.3390\/ph18101505","type":"journal-article","created":{"date-parts":[[2025,10,7]],"date-time":"2025-10-07T15:48:30Z","timestamp":1759852110000},"page":"1505","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Silica Containing Hybrids Loaded with Ibuprofen as Models of Drug Delivery Systems"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8644-6470","authenticated-orcid":false,"given":"Yoanna","family":"Kostova","sequence":"first","affiliation":[{"name":"Institute of Metal Science, Equipment and Technologies with Hydro- and Aerodynamics Centre \u201cAcad. A. Balevski\u201d, Bulgarian Academy of Sciences, Shipchenski Prohod Str., 67, 1574 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pavletta","family":"Shestakova","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 9, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7697-466X","authenticated-orcid":false,"given":"Albena","family":"Bachvarova-Nedelcheva","sequence":"additional","affiliation":[{"name":"Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Catauro, M., and Ciprioti, S.V. (2021). 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