{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T07:58:31Z","timestamp":1789718311891,"version":"4.0.1"},"reference-count":57,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T00:00:00Z","timestamp":1615248000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Research Council (DFG)","award":["PA1751\/10-1"],"award-info":[{"award-number":["PA1751\/10-1"]}]},{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["MSCA-ITN-2017-765441"],"award-info":[{"award-number":["MSCA-ITN-2017-765441"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Cyclodextrins (CDs) have been widely used as pharmaceutical excipients for formulation purposes for different delivery systems. Recent studies have shown that CDs are able to form complexes with a variety of biomolecules, such as cholesterol. This has subsequently paved the way for the possibility of using CDs as drugs in certain retinal diseases, such as Stargardt disease and retinal artery occlusion, where CDs could absorb cholesterol lumps. However, studies on the retinal toxicity of CDs are limited. The purpose of this study was to examine the retinal toxicity of different beta-(\u03b2)CD derivatives and their localization within retinal tissues. To this end, we performed cytotoxicity studies with two different CDs\u20142-hydroxypropyl-\u03b2CD (HP\u03b2CD) and randomly methylated \u03b2-cyclodextrin (RM\u03b2CD)\u2014using wild-type mouse retinal explants, the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and fluorescence microscopy. RM\u03b2CD was found to be more toxic to retinal explants when compared to HP\u03b2CD, which the retina can safely tolerate at levels as high as 10 mM. Additionally, studies conducted with fluorescent forms of the same CDs showed that both CDs can penetrate deep into the inner nuclear layer of the retina, with some uptake by M\u00fcller cells. These results suggest that HP\u03b2CD is a safer option than RM\u03b2CD for retinal drug delivery and may advance the use of CDs in the development of drugs designed for intravitreal administration.<\/jats:p>","DOI":"10.3390\/molecules26051492","type":"journal-article","created":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T12:08:01Z","timestamp":1615291681000},"page":"1492","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Cytotoxicity of \u03b2-Cyclodextrins in Retinal Explants for Intravitreal Drug Formulations"],"prefix":"10.3390","volume":"26","author":[{"given":"Manisha","family":"Prajapati","sequence":"first","affiliation":[{"name":"Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, IS-107 Reykjavik, Iceland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gustav","family":"Christensen","sequence":"additional","affiliation":[{"name":"Institute for Ophthalmic Research, University of T\u00fcbingen, Elfriede-Aulhorn-Strasse 5-7, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fran\u00e7ois","family":"Paquet-Durand","sequence":"additional","affiliation":[{"name":"Institute for Ophthalmic Research, University of T\u00fcbingen, Elfriede-Aulhorn-Strasse 5-7, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9439-1553","authenticated-orcid":false,"given":"Thorsteinn","family":"Loftsson","sequence":"additional","affiliation":[{"name":"Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, IS-107 Reykjavik, Iceland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1517\/17425247.2.1.335","article-title":"Cyclodextrins in drug delivery","volume":"2","author":"Loftsson","year":"2005","journal-title":"Expert Opin. 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