title: Dexamethasone-containing biodegradable superparamagnetic microparticles for intra-articular administration: physicochemical and magnetic properties, in vitro and in vivo drug release.
abstract: Compared with traditional drug solutions or suspensions, polymeric microparticles represent a valuable means to achieve controlled and prolonged drug delivery into joints, but still suffer from the drawback of limited retention duration in the articular cavity. In this study, our aim was to prepare and characterize magnetic biodegradable microparticles containing dexamethasone acetate (DXM) for intra-articular administration. The superparamagnetic properties, which result from the encapsulation of superparamagnetic iron oxide nanoparticles (SPIONs), allow for microparticle retention with an external magnetic field, thus possibly reducing their clearance from the joint. Two molecular weights of poly(lactic-co-glycolic acid) (PLGA) were used, 12 and 19 kDa. The prepared batches were similar in size (around 10 microm), inner morphology, surface morphology, charge (neutral) and superparamagnetic behaviour. The SPION distribution in the microparticles assessed by TEM indicates a homogeneous distribution and the absence of aggregation, an important factor for preserving superparamagnetic properties. DXM release profiles were shown to be quite similar in vitro (ca. 6 days) and in vivo, using a mouse dorsal air pouch model (ca. 5 days).
authors.affiliation: School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland. Nicoleta.Butoescu@unige.ch
authors.forename: Nicoleta
authors.initials: N
authors.lastname: Butoescu
authors.forename: Olivier
authors.initials: O
authors.lastname: Jordan
authors.forename: Pierre
authors.initials: P
authors.lastname: Burdet
authors.forename: Pierre
authors.initials: P
authors.lastname: Stadelmann
authors.forename: Alke
authors.initials: A
authors.lastname: Petri-Fink
authors.forename: Heinrich
authors.initials: H
authors.lastname: Hofmann
authors.forename: Eric
authors.initials: E
authors.lastname: Doelker
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D003461:Crystallography; D003907:Dexamethasone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D005290:Ferric Compounds / Q000737:chemistry; D007270:Injections, Intra-Articular; D008280:Magnetics / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D008863:Microspheres; D014961:X-Ray Diffraction
chemical_list: D005290:Ferric Compounds; C000499:ferric oxide; D003907:Dexamethasone; C018038:dexamethasone acetate