[Biodegradable systems containing prednisolone acetate for orbital administration].
OBJECTIVE
The present study aimed to evaluate an injectable extended-release formulation of prednisolone acetate (PA) for orbital administration.


METHODS
Microspheres (MEs) of poly-e-caprolactone (PCL) containing PA were developed by the method of solvent evaporation. The MEs obtained were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), encapsulation efficiency and in vitro release profile. The in vivo release profile was evaluated in rabbits after periocular injection of an aqueous suspension of MEs. The local biocompatibility of the system was verified by histopathologic analysis of the deployment region.


RESULTS
After MEs preparation, morphological analysis by SEM showed the feasibility of the employed method. The content of PA encapsulated was 43+/-7% and can be considered as satisfactory. The system characterization by DSC technique, in addition to confirm the system stability, did not indicate the existence of interaction between the drug and the polymer. The in vitro release study showed the prolonged-release features of the developed system. Preliminary in vivo study showed the absence of local toxicity and confirmed the prolonged release profile of PA from MEs, suggesting the viability of the developed system for the treatment of orbital inflammatory diseases.


CONCLUSIONS
The results obtained in this work are relevant and accredit the system developed as a possible alternative to the treatment of inflammatory orbitopathy.
Byrro
Ricardo Martins Duarte
RM
Faculdade de Farmácia da Universidade Federal de Minas Gerais-UFMG, Belo Horizonte (MG), Brazil.
Miyashita
Denise
D
Albuquerque
Verônica Batista de
VB
Velasco e Cruz
Antônio Augusto
AA
Cunha Júnior
Armando da Silva
Ada S
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D001672:Biocompatible Materials / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D003692:Delayed-Action Preparations / Q000008:administration & dosage; D004337:Drug Carriers / Q000008:administration & dosage; D005260:Female; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D011091:Polyesters / Q000008:administration & dosage; D011239:Prednisolone / Q000008:administration & dosage / Q000031:analogs & derivatives*; D011817:Rabbits; D014822:Vitreous Body / Q000187:drug effects*
D000893:Anti-Inflammatory Agents; D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D011091:Polyesters; C016240:polycaprolactone; C009935:prednisolone acetate; D011239:Prednisolone