title: Changes in the drug release pattern of fresh and set simvastatin-loaded brushite cement.
abstract: Calcium phosphate cements are synthetic bone graft substitutes able to set at physiological conditions. They can be applied by minimally invasive surgery and can also be used as drug delivery systems. Consequently, the drug release pattern from the cement paste (fresh cement) is of high clinical interest. However, previous studies have commonly evaluated the drug release using pre-set cements only. Therefore, the aim of this work was to determine if the time elapsed from cement preparation until immersion in the solution (3 min for fresh cements, and 1h and 15 h for pre-set cements) had an influence on its physical properties, and correlating these to the drug release profile. Simvastatin was selected as a model drug, while brushite cement was used as drug carrier. This study quantified how the setting of a material reduces the accessibility of the release media to the material, thus preventing drug release. A shift in the drug release pattern was observed, from a burst-release for fresh cements to a sustained release for pre-set cements.
authors.affiliation: Materials in Medicine, Div. of Applied Materials Science, Dept. Engineering Sciences, Uppsala University, Sweden.
authors.forename: Gemma
authors.initials: G
authors.lastname: Mestres
authors.affiliation: Materials in Medicine, Div. of Applied Materials Science, Dept. Engineering Sciences, Uppsala University, Sweden.
authors.forename: Karol
authors.initials: K
authors.lastname: Kugiejko
authors.affiliation: Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), Av. Diagonal 647, 08028 Barcelona, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Pastorino
authors.affiliation: Materials in Medicine, Div. of Applied Materials Science, Dept. Engineering Sciences, Uppsala University, Sweden.
authors.forename: Johanna
authors.initials: J
authors.lastname: Unosson
authors.affiliation: Materials in Medicine, Div. of Applied Materials Science, Dept. Engineering Sciences, Uppsala University, Sweden; Div. of Applied Mechanics, Dept. Engineering Sciences, Uppsala University, Sweden.
authors.forename: Caroline
authors.initials: C
authors.lastname: Öhman
authors.affiliation: Materials in Medicine, Div. of Applied Materials Science, Dept. Engineering Sciences, Uppsala University, Sweden.
authors.forename: Marjam
authors.initials: M
authors.lastname: Karlsson Ott
authors.affiliation: Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), Av. Diagonal 647, 08028 Barcelona, Spain.
authors.forename: Maria-Pau
authors.initials: MP
authors.lastname: Ginebra
authors.affiliation: Materials in Medicine, Div. of Applied Materials Science, Dept. Engineering Sciences, Uppsala University, Sweden. Electronic address: cecilia.persson@angstrom.uu.se.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Persson
mesh_terms: D001843:Bone Cements / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D019821:Simvastatin / Q000737:chemistry / Q000493:pharmacokinetics*
chemical_list: D001843:Bone Cements; D002130:Calcium Phosphates; D019821:Simvastatin; C494366:calcium phosphate, dibasic, dihydrate
keywords: Brushite; Calcium phosphate cement; Local drug release; Setting; Simvastatin; Tortuosity