{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T11:18:53Z","timestamp":1788261533290,"version":"build-2803163510"},"reference-count":54,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>While poly (vinyl alcohol) (PVA)-based aerogels are promising porous carriers for controlled drug delivery, drying-induced pore collapse generally limits their internal pore accessibility, drug-loading capacity, and release regulation. In this study, duration-controlled tert-butanol (TBA) solvent exchange was developed as a pore-engineering strategy to regulate the structure-performance relationship of PVA\/cellulose nanocrystal\/Ca2+ composite aerogels. This strategy focuses on balancing pore preservation, liquid-accessible pore connectivity, and network densification, instead of simply increasing the total surface area. With an optimized exchange duration, the TBA6 aerogel exhibited a well-preserved porous network. Moreover, its specific surface area and porosity increased from 33.11 to 96.02 m2\u00b7g\u22121 and from 93.93% to 96.03%, respectively. This optimized structure enhanced salicylic acid (SA) loading, elevating the equilibrium adsorption capacity from 40.91 to 61.18 mg\u00b7g\u22121. Release kinetic analysis revealed that the Higuchi constant and the Korsmeyer-Peppas release constant decreased from 18.148 to 12.751 and from 25.070 to 17.283%\u00b7h\u22121\/2, respectively, indicating a slower diffusion-regulated release process. Confocal Raman mapping further confirmed that TBA6 promoted a more homogeneous SA distribution within the aerogel matrix and enabled gradual release from the internal porous network. To sum up, controlling solvent-exchange duration is an effective strategy for tuning pore accessibility and diffusion resistance. This study provides new insight into the design of PVA-based composite aerogels for drug-loading and sustained-release applications.<\/jats:p>","DOI":"10.3390\/gels12090791","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T10:32:18Z","timestamp":1788258738000},"page":"791","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Engineering\u00a0Pore Accessibility in PVA\/Cellulose Nanocrystal\/Ca2+ Composite Aerogels for Enhanced Drug Adsorption and Sustained Release"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-8937-8316","authenticated-orcid":false,"given":"Zixuan","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Qianqian","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Hua","family":"Jiang","sequence":"additional","affiliation":[{"name":"College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"data-curation","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2363","DOI":"10.2147\/IJN.S238005","article-title":"Engineering of aerogel-based biomaterials for biomedical applications","volume":"15","author":"Zheng","year":"2020","journal-title":"Int. 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