{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T10:46:40Z","timestamp":1778237200912,"version":"3.51.4"},"reference-count":55,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,17]],"date-time":"2022-02-17T00:00:00Z","timestamp":1645056000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDP\/04378\/2020,  UIDB\/04378\/2020,  LA\/P\/0140\/202019,  UIDP\/04129\/2020,  UIDB\/04129\/2020,  SFRH\/BD\/140829\/2018"],"award-info":[{"award-number":["UIDP\/04378\/2020,  UIDB\/04378\/2020,  LA\/P\/0140\/202019,  UIDP\/04129\/2020,  UIDB\/04129\/2020,  SFRH\/BD\/140829\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Chitin-glucan complex (CGC) hydrogels were fabricated through a freeze\u2013thaw procedure for biopolymer dissolution in NaOH 5 mol\/L, followed by a dialysis step to promote gelation. Compared to a previously reported methodology that included four freeze\u2013thaw cycles, reducing the number of cycles to one had no significant impact on the hydrogels\u2019 formation, as well as reducing the total freezing time from 48 to 18 h. The optimized CGC hydrogels exhibited a high and nearly spontaneous swelling ratio (2528 \u00b1 68%) and a water retention capacity of 55 \u00b1 3%, after 2 h incubation in water, at 37 \u00b0C. Upon loading with caffeine as a model drug, an enhancement of the mechanical and rheological properties of the hydrogels was achieved. In particular, the compressive modulus was improved from 23.0 \u00b1 0.89 to 120.0 \u00b1 61.64 kPa and the storage modulus increased from 149.9 \u00b1 9.8 to 315.0 \u00b1 76.7 kPa. Although the release profile of caffeine was similar in PBS and NaCl 0.9% solutions, the release rate was influenced by the solutions\u2019 pH and ionic strength, being faster in the NaCl solution. These results highlight the potential of CGC based hydrogels as promising structures to be used as drug delivery devices in biomedical applications.<\/jats:p>","DOI":"10.3390\/polym14040785","type":"journal-article","created":{"date-parts":[[2022,2,17]],"date-time":"2022-02-17T20:26:41Z","timestamp":1645129601000},"page":"785","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Chitin-Glucan Complex Hydrogels: Optimization of Gel Formation and Demonstration of Drug Loading and Release Ability"],"prefix":"10.3390","volume":"14","author":[{"given":"Diana","family":"Ara\u00fajo","sequence":"first","affiliation":[{"name":"Associate Laboratory i4HB, School of Science and Technology, Institute for Health and Bioeconomy, NOVA University Lisbon, 2819-516 Caparica, Portugal"},{"name":"UCIBIO, Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal"}]},{"given":"Thomas","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"Associate Laboratory i4HB, School of Science and Technology, Institute for Health and Bioeconomy, NOVA University Lisbon, 2819-516 Caparica, Portugal"},{"name":"UCIBIO, Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4117-5582","authenticated-orcid":false,"given":"V\u00edtor D.","family":"Alves","sequence":"additional","affiliation":[{"name":"LEAF, Linking Landscape, Environment, Agriculture and Food Research Center, Laborat\u00f3rio Associado TERRA, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9430-4640","authenticated-orcid":false,"given":"Filomena","family":"Freitas","sequence":"additional","affiliation":[{"name":"Associate Laboratory i4HB, School of Science and Technology, Institute for Health and Bioeconomy, NOVA University Lisbon, 2819-516 Caparica, Portugal"},{"name":"UCIBIO, Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"574","DOI":"10.1080\/00914037.2020.1740989","article-title":"An overview of hydrogels and their role in transdermal drug delivery","volume":"70","author":"Ahsan","year":"2021","journal-title":"Int. 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