title: Spray-dried diclofenac-loaded poly(epsilon-caprolactone) nanocapsules and nanospheres. Preparation and physicochemical characterization.
abstract: The aims of the present study were to prepare spray-dried polymeric nanocapsules (NC) and nanospheres (NS) from poly(epsilon-caprolactone) (P epsilon C) suspensions containing diclofenac (DIC) and to determine the physicochemical properties of the formulations. NC or NS suspensions were prepared by interfacial deposition of the polymer. DSC-thermograms of raw materials and NC or NS suspensions (evaporated or spray-dried) were obtained using a PL-DSC. Spray-dried powders were prepared by addition of 3% (w/v) Aerosil 200 into suspensions of NC or NS. These mixtures were fed into a spray-dryer. DIC was assayed by HPLC. NC and NS spray-dried powders were examined under SEM (Jeol Scanning Microscope, JSM-5800). NC and NS suspensions had acceptable diameter, 340 and 247 nm respectively. The yields of NC and NS spray-dried powders were 80% and 75% and the recovery of the DIC was 99% and 93%, respectively. The melting peak of P epsilon C in NC and NS was observed at a temperature about 10 degrees C lower than in the raw material. In the NC thermograms the maximum of the oil (Miglyol 810) melting peak (+1.6 degrees C) was lowered about 7 degrees C. For spray-dried NC formulations, the SEM analyses of powders showed spherical microparticles of silicon dioxide, covered by nanoparticles (300 nm), while for spray-dried NS formulations the microparticles presented a rugged surface at the same magnification.
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brasil.
authors.forename: C R
authors.initials: CR
authors.lastname: Müller
authors.forename: S R
authors.initials: SR
authors.lastname: Schaffazick
authors.forename: A R
authors.initials: AR
authors.lastname: Pohlmann
authors.forename: L
authors.initials: L
authors.lastname: de Lucca Freitas
authors.forename: N
authors.initials: N
authors.lastname: Pesce da Silveira
authors.forename: T
authors.initials: T
authors.lastname: Dalla Costa
authors.forename: S S
authors.initials: SS
authors.lastname: Guterres
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D002208:Caproates; D002214:Capsules; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003102:Colloids; D004008:Diclofenac / Q000008:administration & dosage / Q000737:chemistry*; D004563:Electrochemistry; D005079:Excipients; D007783:Lactones; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011208:Powders; D013535:Suspensions
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002208:Caproates; D002214:Capsules; D003102:Colloids; D005079:Excipients; D007783:Lactones; D011208:Powders; D013535:Suspensions; D004008:Diclofenac; C121056:caprolactone