{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T08:06:00Z","timestamp":1773907560348,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,7,19]],"date-time":"2022-07-19T00:00:00Z","timestamp":1658188800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"M\u0101nuka Health New Zealand"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Honey has been widely purported as a natural remedy due to its antimicrobial and anti-inflammatory effects. In recent years, several studies have suggested that the considerably high methylglyoxal (MGO) concentration in M\u0101nuka honey (MH) makes it particularly effective to manage bacterial overload, such as that observed in blepharitis. However, the poor solubility, high viscosity, and osmolarity of aqueous honey solutions, especially at the high MGO concentrations studied in the literature, render the formulation of an acceptable dosage form for topical application to the eyelids challenging. Here, the antibacterial properties of raw MH and alpha-cyclodextrin (\u03b1-CD)-complexed MH were evaluated at relatively low MGO concentrations, and a liquid crystalline-forming microemulsion containing \u03b1-CD-complexed MH was formulated. After determining pH and osmolarity, ocular tolerability was assessed using human primary corneal epithelial cells and chorioallantoic membranes, while the antibacterial efficacy was further evaluated in vitro. The \u03b1-CD\u2013MH complex had significantly greater antibacterial activity against Staphylococcus aureus than either constituent alone, which was evident even when formulated as a microemulsion. Moreover, the final formulation had a physiologically acceptable pH and osmolarity for eyelid application and was well-tolerated when diluted 1:10 with artificial tear fluid, as expected to be the case after accidental exposure to the ocular surface in the clinical setting. Thus, a safe and efficient MH dosage form was developed for topical application to the eyelids, which can potentially be used to support optimal eyelid health in the management of blepharitis.<\/jats:p>","DOI":"10.3390\/pharmaceutics14071493","type":"journal-article","created":{"date-parts":[[2022,7,19]],"date-time":"2022-07-19T08:28:25Z","timestamp":1658219305000},"page":"1493","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Preparation and Characterisation of a Cyclodextrin-Complexed M\u0101nuka Honey Microemulsion for Eyelid Application"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5997-5994","authenticated-orcid":false,"given":"Ilva D.","family":"Rupenthal","sequence":"first","affiliation":[{"name":"Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3831-3833","authenticated-orcid":false,"given":"Priyanka","family":"Agarwal","sequence":"additional","affiliation":[{"name":"Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4058-4314","authenticated-orcid":false,"given":"Benedict","family":"Uy","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jaeun","family":"Kim","sequence":"additional","affiliation":[{"name":"Ocular Surface Laboratory, Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angela A.","family":"Cunningham","sequence":"additional","affiliation":[{"name":"Ocular Surface Laboratory, Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4343-9905","authenticated-orcid":false,"given":"Ali","family":"Seyfoddin","sequence":"additional","affiliation":[{"name":"Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7352-1112","authenticated-orcid":false,"given":"Simon","family":"Swift","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8297-5319","authenticated-orcid":false,"given":"Jennifer P.","family":"Craig","sequence":"additional","affiliation":[{"name":"Ocular Surface Laboratory, Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"569","DOI":"10.3389\/fmicb.2016.00569","article-title":"Therapeutic Manuka Honey: No Longer So Alternative","volume":"7","author":"Carter","year":"2016","journal-title":"Front. 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