title: Surface drug removal from ibuprofen-loaded PLA microspheres.
abstract: The preparation, characterisation and drug release behaviour of ibuprofen loaded poly(D,L-lactic acid) (PLA) microspheres are described. Depending on the gelatin concentration in the aqueous external solution (1, 0.5, 0.1% w/v), microspheres with three different sizes (2.2, 4.1, 7.5 micrometer) were obtained. The properties of microspheres washed with water (Untreated microspheres) (Un-Ms) were compared to those of the microspheres washed with a sodium carbonate solution in order to remove the surface drug (treated microspheres) (T-Ms). The results indicate that the removal of the surface drug did not induce any change in the size of the microspheres whereas the morphology of the smallest T-Ms appeared to be modified. The release profiles of both Un-Ms and T-Ms resulted in biphasic patterns. The initial burst effect (first release phase) of the T-Ms was lower than that of the Un-Ms. The rate of the second release phase did not change for the microspheres with the biggest size but increased for the smallest microspheres probably owing to the modification of the matrix porosity.
authors.affiliation: Department of Pharmaceutical Sciences, University of Modena and Reggio Emilia, Via Campi, 183, 41100, Modena, Italy. leo.eliana@unimo.it
authors.forename: E
authors.initials: E
authors.lastname: Leo
authors.forename: F
authors.initials: F
authors.lastname: Forni
authors.forename: M T
authors.initials: MT
authors.lastname: Bernabei
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000737:chemistry*; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D002254:Carbonates / Q000737:chemistry; D003692:Delayed-Action Preparations; D004339:Drug Compounding; D007052:Ibuprofen / Q000008:administration & dosage / Q000737:chemistry*; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011091:Polyesters / Q000008:administration & dosage / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D001672:Biocompatible Materials; D002254:Carbonates; D003692:Delayed-Action Preparations; D011091:Polyesters; D014867:Water; C033616:poly(lactide); C005686:sodium carbonate; D007052:Ibuprofen