{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,15]],"date-time":"2026-08-15T09:08:10Z","timestamp":1786784890545,"version":"build-2736575974"},"reference-count":30,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,4,16]],"date-time":"2023-04-16T00:00:00Z","timestamp":1681603200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Project of Junta de Andalucia (Spain)","award":["P18-RT-3786"],"award-info":[{"award-number":["P18-RT-3786"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Bentonite or palygorskite-based hydrogels have recently been suggested as a strategy to increase bioavailability and control the retention and release of therapeutic candidates. In this work, clay-based hydrogels loaded with diclofenac acid nanocrystals have been successfully designed and developed. The aim was to improve diclofenac solubility, its dissolution rate and to enhance its local bioavailability after topical application. For this purpose, diclofenac acid nanocrystals were prepared by wet media milling technology and then loaded into inorganic hydrogels based on bentonite and\/or palygorskite. Diclofenac acid nanocrystals were characterized by morphology, size, and zeta potential. Moreover, rheological behavior, morphology, solid state, release studies, and in vitro skin penetration\/permeation of diclofenac acid nanocrystals-loaded hydrogels were performed. The hydrogels were characterized by a crystalline structure, and demonstrated that the inclusion of diclofenac in clay-based hydrogels resulted in an increased thermal stability. The presence of both palygorskite and bentonite reduced nanocrystal mobility, and consequently its release and penetration into the skin. On the other hand, bentonite- or palygorskite-based hydrogels revealed great potential as an alternative strategy to enhance topical bioavailability of DCF nanocrystals, enhancing their penetration to the deeper skin layers.<\/jats:p>","DOI":"10.3390\/pharmaceutics15041253","type":"journal-article","created":{"date-parts":[[2023,4,17]],"date-time":"2023-04-17T01:34:15Z","timestamp":1681695255000},"page":"1253","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Bentonite- and Palygorskite-Based Gels for Topical Drug Delivery Applications"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4192-5416","authenticated-orcid":false,"given":"Marco","family":"Ruggeri","sequence":"first","affiliation":[{"name":"Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6525-5723","authenticated-orcid":false,"given":"Rita","family":"S\u00e1nchez-Espejo","sequence":"additional","affiliation":[{"name":"Department of Pharmacy and Pharmaceutical Technology, University of Granada, 18071 Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9508-7222","authenticated-orcid":false,"given":"Luca","family":"Casula","sequence":"additional","affiliation":[{"name":"Department of Life and Environmental Sciences, Unit of Drug Sciences, University of Cagliari, 09124 Cagliari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6766-9321","authenticated-orcid":false,"given":"Giuseppina","family":"Sandri","sequence":"additional","affiliation":[{"name":"Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3890-3283","authenticated-orcid":false,"given":"Luana","family":"Perioli","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo 1, 06123 Perugia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2788-7823","authenticated-orcid":false,"given":"Maria Cristina","family":"Cardia","sequence":"additional","affiliation":[{"name":"Department of Life and Environmental Sciences, Unit of Drug Sciences, University of Cagliari, 09124 Cagliari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"Lai","sequence":"additional","affiliation":[{"name":"Department of Life and Environmental Sciences, Unit of Drug Sciences, University of Cagliari, 09124 Cagliari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2219-3566","authenticated-orcid":false,"given":"C\u00e9sar","family":"Viseras","sequence":"additional","affiliation":[{"name":"Department of Pharmacy and Pharmaceutical Technology, University of Granada, 18071 Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"105772","DOI":"10.1016\/j.clay.2020.105772","article-title":"Design and characterization of spring water hydrogels with natural inorganic excipients","volume":"197","author":"Cerezo","year":"2020","journal-title":"Appl. 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