{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:58:12Z","timestamp":1760237892964,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,7,1]],"date-time":"2020-07-01T00:00:00Z","timestamp":1593561600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFB"],"abstract":"<jats:p>Extended bone fractures or fractures coexisting with bone disorders can lead to non-unions where surgical intervention is required. Composite drug delivery systems are being used increasingly more in order to treat such defects locally. Alendronate (ALD), a bisphosphonate extensively used in clinical practice to treat conditions, such as osteoporosis, has been shown to assist bone fracture healing through its antiresorptive capacity. This study reports the development of a polymeric composite system for the in situ delivery of ALD, which possesses enhanced encapsulation efficiency (EE%) and demonstrates controlled release over a 70-day period. ALD and calcium phosphate (CaP) were incorporated within poly (lactic-co-glycolic acid) (PLGA) microspheres, giving rise to a 70% increase in EE% compared to a control system. Finally, a preliminary toxicological evaluation demonstrated a positive effect of the system on pre-osteoblastic cells over 72 h.<\/jats:p>","DOI":"10.3390\/jfb11030046","type":"journal-article","created":{"date-parts":[[2020,7,2]],"date-time":"2020-07-02T02:44:25Z","timestamp":1593657865000},"page":"46","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Feedback-Controlled Release of Alendronate from Composite Microparticles"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5923-0746","authenticated-orcid":false,"given":"Sofia S. H.","family":"Matrali","sequence":"first","affiliation":[{"name":"School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6650-3394","authenticated-orcid":false,"given":"Anita K.","family":"Ghag","sequence":"additional","affiliation":[{"name":"School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1539","DOI":"10.1002\/btpr.246","article-title":"Bone Tissue Engineering: A Review in Bone Biomimetics and Drug Delivery Strategies","volume":"25","author":"Porter","year":"2009","journal-title":"Biotechnol. Prog."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Bosworth, L.A., and Downes, S. (2011). Bone tissue regeneration. 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