eprintid: 10053213 rev_number: 23 eprint_status: archive userid: 608 dir: disk0/10/05/32/13 datestamp: 2018-07-27 16:53:35 lastmod: 2021-09-20 22:26:27 status_changed: 2018-07-27 16:53:35 type: article metadata_visibility: show creators_name: Burgess, K creators_name: Li, H creators_name: Abo-zeid, Y creators_name: Fatimah, and creators_name: Williams, GR title: The Effect of Molecular Properties on Active Ingredient Release from Electrospun Eudragit Fibers ispublished: pub divisions: UCL divisions: B02 divisions: C08 divisions: D10 divisions: G08 keywords: electrospinning; Eudragit; nanofibers; drug release note: © 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). abstract: The formation of nanoscale fibers from pH-sensitive polymers is a route which has been widely explored for targeted drug delivery. In particular, the Eudragit L100 and S100 families of polymers have received significant attention for this purpose. However, while in some cases it is shown that making drug-loaded Eudragit polymers effectively prevents drug release in low-pH media where the polymer is insoluble, this is not always the case, and other studies have reported significant amounts of drug release at acidic pHs. In this study, we sought to gain insight into the factors influencing the release of active ingredients from Eudragit S100 (ES100) fibers. A family of materials was prepared loaded with the model active ingredients (AIs) benzoic acid, 1-naphthoic acid, 1-naphthylamine, and 9-anthracene carboxylic acid. Analogous systems were prepared with an AI-loaded core and an ES100 sheath. The resultant fibers were smooth and cylindrical in the majority of cases, and X-ray diffraction and differential scanning calorimetry showed them to comprise amorphous solid dispersions. When AI release from the monolithic fibers was probed, it was found that there was significant release at pH 1 in all cases except with 9-anthracene carboxylic acid. Analysis of the results indicated that both the molecular weight of the AI and its acidity/basicity are important in controlling release, with lower molecular weight AIs and basic species released more quickly. The same release trends are seen with the core/shell fibers, but AI release at pH 1 is attenuated. The most significant change between the monolithic and core/shell systems was observed in the case of 1-naphthylamine. Mathematical equations were devised to connect molecular properties and AI release under acidic conditions. date: 2018-07-24 date_type: published publisher: MDPI AG official_url: http://doi.org/10.3390/pharmaceutics10030103 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1571085 doi: 10.3390/pharmaceutics10030103 lyricists_name: Abozeid, Yasmin lyricists_name: Fatimah, Fatimah lyricists_name: Li, Heyu lyricists_name: Williams, Gareth lyricists_id: YABOZ97 lyricists_id: FATIM29 lyricists_id: HLIBX67 lyricists_id: GWILL02 actors_name: Williams, Gareth actors_id: GWILL02 actors_role: owner full_text_status: public publication: Pharmaceutics volume: 10 number: 3 article_number: 103 issn: 1999-4923 citation: Burgess, K; Li, H; Abo-zeid, Y; Fatimah, and; Williams, GR; (2018) The Effect of Molecular Properties on Active Ingredient Release from Electrospun Eudragit Fibers. Pharmaceutics , 10 (3) , Article 103. 10.3390/pharmaceutics10030103 <https://doi.org/10.3390/pharmaceutics10030103>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10053213/1/GRW%20Pharmaceutics%202018.pdf