{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T13:40:25Z","timestamp":1768052425451,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,10,18]],"date-time":"2021-10-18T00:00:00Z","timestamp":1634515200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Science and Technology Foundation (FCT) from the Ministry of Science and Technology (MCTES), European Social Fund (FSE) of EU, for the scholarship SFRH\/BD\/130555\/2017 granted to A. R. Fernandes, and for the projects UIDB\/04469\/2020 (CEB strateg","award":["SFRH\/BD\/130555\/2017 granted to A. R. Fernandes, and for the projects UIDB\/04469\/2020 (CEB strategic fund) and UIDB\/04033\/2020 (CITAB)"],"award-info":[{"award-number":["SFRH\/BD\/130555\/2017 granted to A. R. Fernandes, and for the projects UIDB\/04469\/2020 (CEB strategic fund) and UIDB\/04033\/2020 (CITAB)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Oil-in-water nanoemulsions (NEs) are considered a suitable nanotechnological approach to improve the eye-related bioavailability of lipophilic drugs. The potential of cationic NEs is prominent due to the electrostatic interaction that occurs between the positively charged droplets with the negatively charged mucins present in the tear film. This interaction offers prolonged NEs residence at the ocular surface, increasing the drug absorption. Triamcinolone acetonide (TA) is one of the first pharmacologic strategies applied as an intravitreal injection in the treatment of age-related macular degeneration (AMD). Newly synthesized quaternary derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO) and quinuclidine surfactants have been screened with the purpose to select the best compound to formulate long-term stable NEs that combine the best physicochemical properties for the loading of TA intended for ocular administration.<\/jats:p>","DOI":"10.3390\/nano11102758","type":"journal-article","created":{"date-parts":[[2021,10,19]],"date-time":"2021-10-19T22:52:47Z","timestamp":1634683967000},"page":"2758","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Mono- and Dicationic DABCO\/Quinuclidine Composed Nanomaterials for the Loading of Steroidal Drug: 32 Factorial Design and Physicochemical Characterization"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8787-7854","authenticated-orcid":false,"given":"Ana R.","family":"Fernandes","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, P\u00f3lo das Ci\u00eancias da Sa\u00fade, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal"},{"name":"i3s\u2014Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal"},{"name":"INEB\u2014Instituto de Engenharia Biom\u00e9dica, Universidade do Porto, Alfredo Allen 208, 4200-135 Porto, Portugal"},{"name":"Faculdade de Engenharia, Universidade do Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2571-108X","authenticated-orcid":false,"given":"Elena","family":"Sanchez-Lopez","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain"},{"name":"Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5505-3327","authenticated-orcid":false,"given":"Antonello","family":"Santini","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Universit\u00e0 di Napoli Federico II, Via D. Montesano 49, 80131 Napoli, Italy"}]},{"given":"Tiago dos","family":"Santos","sequence":"additional","affiliation":[{"name":"i3s\u2014Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal"},{"name":"INEB\u2014Instituto de Engenharia Biom\u00e9dica, Universidade do Porto, Alfredo Allen 208, 4200-135 Porto, Portugal"}]},{"given":"Maria L.","family":"Garcia","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain"},{"name":"Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7524-9914","authenticated-orcid":false,"given":"Am\u00e9lia M.","family":"Silva","sequence":"additional","affiliation":[{"name":"Department of Biology and Environment, University of Tr\u00e1s-os-Montes e Alto Douro, UTAD, Quinta de Prados, 5001-801 Vila Real, Portugal"},{"name":"Centre for Research and Technology of Agro-Environmental and Biological Sciences, CITAB, UTAD, Quinta de Prados, 5001-801 Vila Real, Portugal"}]},{"given":"Eliana B.","family":"Souto","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, P\u00f3lo das Ci\u00eancias da Sa\u00fade, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal"},{"name":"CEB\u2014Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.ejpb.2014.02.005","article-title":"Nanotoxicology applied to solid lipid nanoparticles and nanostructured lipid carriers\u2014A systematic review of in vitro data","volume":"87","author":"Doktorovova","year":"2014","journal-title":"Eur. 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