{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T04:11:38Z","timestamp":1790482298083,"version":"4.1.0"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,19]],"date-time":"2022-02-19T00:00:00Z","timestamp":1645228800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Cochlear implants, like other active implants, rely on precise and effective electrical stimulation of the target tissue but become encapsulated by different amounts of fibrous tissue. The current study aimed at the development of a dual drug release from a PLLA coating and from the bulk material to address short-term and long-lasting release of anti-inflammatory drugs. Inner-ear cytocompatibility of drugs was studied in vitro. A PLLA coating (containing diclofenac) of medical-grade silicone (containing 5% dexamethasone) was developed and release profiles were determined. The influence of different coating thicknesses (2.5, 5 and 10 \u00b5m) and loadings (10% and 20% diclofenac) on impedances of electrical contacts were measured with and without pulsatile electrical stimulation. Diclofenac can be applied to the inner ear at concentrations of or below 4 \u00d7 10\u22125 mol\/L. Release of dexamethasone from the silicone is diminished by surface coating but not blocked. Addition of 20% diclofenac enhances the dexamethasone release again. All PLLA coatings serve as insulator. This can be overcome by using removable masking on the contacts during the coating process. Dual drug release with different kinetics can be realized by adding drug-loaded coatings to drug-loaded silicone arrays without compromising electrical stimulation.<\/jats:p>","DOI":"10.3390\/molecules27041417","type":"journal-article","created":{"date-parts":[[2022,2,21]],"date-time":"2022-02-21T08:22:19Z","timestamp":1645431739000},"page":"1417","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["PLLA Coating of Active Implants for Dual Drug Release"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9891-5174","authenticated-orcid":false,"given":"Katharina","family":"Wulf","sequence":"first","affiliation":[{"name":"Institute for Biomedical Engineering, University Medical Center Rostock, 18119 Rostock, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madeleine","family":"Goblet","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Head and Neck Surgery and Hearing4all Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Raggl","sequence":"additional","affiliation":[{"name":"MED-EL Medical Electronics, Fuerstenweg 77a, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Teske","sequence":"additional","affiliation":[{"name":"Institute for Biomedical Engineering, University Medical Center Rostock, 18119 Rostock, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Eickner","sequence":"additional","affiliation":[{"name":"Institute for Biomedical Engineering, University Medical Center Rostock, 18119 Rostock, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9307-5989","authenticated-orcid":false,"given":"Thomas","family":"Lenarz","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Head and Neck Surgery and Hearing4all Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Niels","family":"Grabow","sequence":"additional","affiliation":[{"name":"Institute for Biomedical Engineering, University Medical Center Rostock, 18119 Rostock, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gerrit","family":"Paasche","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Head and Neck Surgery and Hearing4all Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"446","DOI":"10.1080\/14992020600690969","article-title":"Telephone use: What benefit do cochlear implant users receive?","volume":"45","author":"Anderson","year":"2006","journal-title":"Int. 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