{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T14:42:21Z","timestamp":1775486541022,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2022,10,5]],"date-time":"2022-10-05T00:00:00Z","timestamp":1664928000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["UID\/QUI\/00686\/2019"],"award-info":[{"award-number":["UID\/QUI\/00686\/2019"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["UIDP\/CTM\/05256\/2020"],"award-info":[{"award-number":["UIDP\/CTM\/05256\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["UIDB\/05256\/2020"],"award-info":[{"award-number":["UIDB\/05256\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}]},{"name":"IPC","award":["UID\/QUI\/00686\/2019"],"award-info":[{"award-number":["UID\/QUI\/00686\/2019"]}]},{"name":"IPC","award":["UIDP\/CTM\/05256\/2020"],"award-info":[{"award-number":["UIDP\/CTM\/05256\/2020"]}]},{"name":"IPC","award":["UIDB\/05256\/2020"],"award-info":[{"award-number":["UIDB\/05256\/2020"]}]},{"name":"IPC","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}]},{"name":"REQUIMTE\/LAQV","award":["UID\/QUI\/00686\/2019"],"award-info":[{"award-number":["UID\/QUI\/00686\/2019"]}]},{"name":"REQUIMTE\/LAQV","award":["UIDP\/CTM\/05256\/2020"],"award-info":[{"award-number":["UIDP\/CTM\/05256\/2020"]}]},{"name":"REQUIMTE\/LAQV","award":["UIDB\/05256\/2020"],"award-info":[{"award-number":["UIDB\/05256\/2020"]}]},{"name":"REQUIMTE\/LAQV","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Employing amino acids and peptides as molecular building blocks provides unique opportunities for generating supramolecular hydrogels, owing to their inherent biological origin, bioactivity, biocompatibility, and biodegradability. However, they can suffer from proteolytic degradation. Short peptides (&lt;8 amino acids) attached to an aromatic capping group are particularly attractive alternatives for minimalistic low molecular weight hydrogelators. Peptides with low critical gelation concentrations (CGCs) are especially desirable, as the low weight percentage required for gelation makes them more cost-effective and reduces toxicity. In this work, three dehydrodipeptides were studied for their self-assembly properties. The results showed that all three dehydrodipeptides can form self-standing hydrogels with very low critical gelation concentrations (0.05\u20130.20 wt%) using a pH trigger. Hydrogels of all three dehydrodipeptides were characterised by scanning tunnelling emission microscopy (STEM), rheology, fluorescence spectroscopy, and circular dichroism (CD) spectroscopy. Molecular modelling was performed to probe the structural patterns and interactions. The cytotoxicity of the new compounds was tested using human keratinocytes (HaCaT cell line). In general, the results suggest that all three compounds are non-cytotoxic, although one of the peptides shows a small impact on cell viability. In sustained release assays, the effect of the charge of the model drug compounds on the rate of cargo release from the hydrogel network was evaluated. The hydrogels provide a sustained release of methyl orange (anionic) and ciprofloxacin (neutral), while methylene blue (cationic) was retained by the network.<\/jats:p>","DOI":"10.3390\/ijms231911811","type":"journal-article","created":{"date-parts":[[2022,10,8]],"date-time":"2022-10-08T23:39:31Z","timestamp":1665272371000},"page":"11811","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Aryl-Capped Lysine-Dehydroamino Acid Dipeptide Supergelators as Potential Drug Release Systems"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5340-4151","authenticated-orcid":false,"given":"Carlos B. P.","family":"Oliveira","sequence":"first","affiliation":[{"name":"Chemistry Centre, School of Sciences, University of Minho, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8500-7364","authenticated-orcid":false,"given":"Renato B.","family":"Pereira","sequence":"additional","affiliation":[{"name":"REQUIMTE\/LAQV, Laborat\u00f3rio de Farmacognosia, Departamento de Qu\u00edmica, Faculdade de Farm\u00e1cia, Universidade do Porto, R. Jorge Viterbo Ferreira, n 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0384-7592","authenticated-orcid":false,"given":"David M.","family":"Pereira","sequence":"additional","affiliation":[{"name":"REQUIMTE\/LAQV, Laborat\u00f3rio de Farmacognosia, Departamento de Qu\u00edmica, Faculdade de Farm\u00e1cia, Universidade do Porto, R. Jorge Viterbo Ferreira, n 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9936-8088","authenticated-orcid":false,"given":"Loic","family":"Hilliou","sequence":"additional","affiliation":[{"name":"Institute for Polymers and Composites, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1040-459X","authenticated-orcid":false,"given":"Tarsila G.","family":"Castro","sequence":"additional","affiliation":[{"name":"Center of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"},{"name":"LABBELS\u2014Associate Laboratory, 4800-122 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9323-3978","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Martins","sequence":"additional","affiliation":[{"name":"Chemistry Centre, School of Sciences, University of Minho, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5550-4535","authenticated-orcid":false,"given":"Peter J.","family":"Jervis","sequence":"additional","affiliation":[{"name":"Chemistry Centre, School of Sciences, University of Minho, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3279-6731","authenticated-orcid":false,"given":"Paula M. T.","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Chemistry Centre, School of Sciences, University of Minho, 4710-057 Braga, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1154","DOI":"10.1002\/anie.199611541","article-title":"Self-assembly in natural and unnatural systems","volume":"35","author":"Philip","year":"1996","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"582","DOI":"10.1002\/wnan.1238","article-title":"Self-assembly in nature: Using the principles of nature to create complex nanobiomaterials","volume":"5","author":"Mendes","year":"2015","journal-title":"WIREs Nanomed. 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