{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T04:57:49Z","timestamp":1774933069479,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,1,22]],"date-time":"2020-01-22T00:00:00Z","timestamp":1579651200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003141","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","award":["PDCPN-2015-89"],"award-info":[{"award-number":["PDCPN-2015-89"]}],"id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003141","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","award":["INFR-2015-251863"],"award-info":[{"award-number":["INFR-2015-251863"]}],"id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Hydrogels for load-bearing biomedical applications, such as soft tissue replacement, are required to be tough and biocompatible. In this sense, alginate-methacrylate hydrogels (H-ALGMx) are well known to present modulable levels of elasticity depending on the methacrylation degree; however, little is known about the role of additional structural parameters. In this work, we present an experimental-computational approach aimed to evaluate the effect of the molecular conformation and electron density of distinct methacrylate groups on the mechanical properties of photocrosslinked H-ALGMx hydrogels. Three alginate-methacrylate precursor macromers (ALGMx) were synthesized: alginate-glycidyl methacrylate (ALGM1), alginate-2-aminoethyl methacrylate (ALGM2), and alginate-methacrylic anhydride (ALGM3). The macromers were studied by Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and density functional theory method (DFT) calculations to assess their molecular\/electronic configurations. In parallel, they were also employed to produce H-ALGMx hydrogels, which were characterized by compressive tests. The obtained results demonstrated that tougher hydrogels were produced from ALGMx macromers presenting the C=C reactive bond with an outward orientation relative to the polymer chain and showing free rotation, which favored in conjunction the covalent crosslinking. In addition, although playing a secondary role, it was also found that the presence of acid hydrogen atoms in the methacrylate unit enables the formation of supramolecular hydrogen bonds, thereby reinforcing the mechanical properties of the H-ALGMx hydrogels. By contrast, impaired mechanical properties resulted from macromer conditions in which the C=C bond adopted an inward orientation to the polymer chain accompanied by a torsional impediment.<\/jats:p>","DOI":"10.3390\/ma13030534","type":"journal-article","created":{"date-parts":[[2020,1,22]],"date-time":"2020-01-22T11:17:57Z","timestamp":1579691877000},"page":"534","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":56,"title":["Photocrosslinked Alginate-Methacrylate Hydrogels with Modulable Mechanical Properties: Effect of the Molecular Conformation and Electron Density of the Methacrylate Reactive Group"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2426-7896","authenticated-orcid":false,"given":"Fernanda","family":"Araiza-Verduzco","sequence":"first","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico\/I. T. Tijuana. Centro de Graduados e Investigaci\u00f3n en Qu\u00edmica-Grupo de Biomateriales y Nanomedicina, Blvd. Alberto Lim\u00f3n Padilla S\/N, Tijuana 22510, BC, Mexico"}]},{"given":"Eustolia","family":"Rodr\u00edguez-Vel\u00e1zquez","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico\/I. T. Tijuana. Centro de Graduados e Investigaci\u00f3n en Qu\u00edmica-Grupo de Biomateriales y Nanomedicina, Blvd. Alberto Lim\u00f3n Padilla S\/N, Tijuana 22510, BC, Mexico"},{"name":"Facultad de Odontolog\u00eda, Universidad Aut\u00f3noma de Baja California, Campus Tijuana, Calzada Universidad 14418, Tijuana 22390, BC, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2205-6577","authenticated-orcid":false,"given":"Harold","family":"Cruz","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico\/I. T. Tijuana. Centro de Graduados e Investigaci\u00f3n en Qu\u00edmica, Blvd. Alberto Lim\u00f3n Padilla S\/N, Tijuana 22510, BC, Mexico"}]},{"given":"Ignacio A.","family":"Rivero","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico\/I. T. Tijuana. Centro de Graduados e Investigaci\u00f3n en Qu\u00edmica, Blvd. Alberto Lim\u00f3n Padilla S\/N, Tijuana 22510, BC, Mexico"}]},{"given":"Delvis R.","family":"Acosta-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico\/I. T. Tijuana. Centro de Graduados e Investigaci\u00f3n en Qu\u00edmica-Grupo de Biomateriales y Nanomedicina, Blvd. Alberto Lim\u00f3n Padilla S\/N, Tijuana 22510, BC, Mexico"}]},{"given":"Georgina","family":"Pina-Luis","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico\/I. T. Tijuana. Centro de Graduados e Investigaci\u00f3n en Qu\u00edmica, Blvd. Alberto Lim\u00f3n Padilla S\/N, Tijuana 22510, BC, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3301-9619","authenticated-orcid":false,"given":"Manuel","family":"Alatorre-Meda","sequence":"additional","affiliation":[{"name":"C\u00e1tedras CONACyT-Tecnol\u00f3gico Nacional de M\u00e9xico\/I. T. Tijuana. Centro de Graduados e Investigaci\u00f3n en Qu\u00edmica-Grupo de Biomateriales y Nanomedicina, Blvd. Alberto Lim\u00f3n Padilla S\/N, Tijuana 22510, BC, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4337","DOI":"10.1016\/S0142-9612(03)00340-5","article-title":"Hydrogels for tissue engineering: Scaffold design variables and applications","volume":"24","author":"Drury","year":"2003","journal-title":"Biomaterials"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Chai, Q., Jiao, Y., and Yu, X. (2017). 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