title: Double-walled microspheres loaded with meglumine antimoniate: preparation, characterization and in vitro release study.
abstract: OBJECTIVE
  The objective of this study was to fabricate double-walled poly(lactide-co-glycolide) (PLGA) microspheres to increase encapsulation efficiency and avoid rapid release of hydrophilic drugs such as meglumine antimoniate.
  
  
  METHODS
  In this study, double-walled and one-layered microspheres of PLGA were prepared using the emulsion solvent evaporation technique to better control the release of a hydrophilic drug, meglumine antimoniate (Glucantime®), which is the first choice treatment of cutaneous leishmaniasis. The effect of hydrophobic coating on microspheres' size, morphology, encapsulation efficiency and drug release characteristics was evaluated. Furthermore, the presence of antimony in meglumine antimoniate made it possible to observe the drug distribution within the microspheres' cross section by means of energy dispersive X-ray spectroscopy.
  
  
  RESULTS
  Drug distribution images confirmed accumulation of the drug within the inner core of double-walled microspheres. In addition, these microspheres encapsulated the drug more efficiently up to 87% and demonstrated reduced initial burst and prolonged release compared to one-layered microspheres. These superiorities make double-walled microspheres an optimum candidate for sustained delivery of hydrophilic drugs.
  
  
  CONCLUSIONS
  Double-walled microspheres provide some advantages over traditional microspheres overcoming most of their limitations. Double-walled microspheres were found to be more efficient than their corresponding one-layered microspheres in terms of encapsulation efficiencies and release characteristics.
authors.affiliation: Biomedical Engineering Department, Amirkabir University of Technology , Tehran , Iran .
authors.forename: Ali
authors.initials: A
authors.lastname: Navaei
authors.forename: Morteza
authors.initials: M
authors.lastname: Rasoolian
authors.forename: Arash
authors.initials: A
authors.lastname: Momeni
authors.forename: Shahriar
authors.initials: S
authors.lastname: Emami
authors.forename: Mohammad
authors.initials: M
authors.lastname: Rafienia
mesh_terms: D000981:Antiprotozoal Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D002152:Calorimetry, Differential Scanning; D002626:Chemistry, Pharmaceutical; D004337:Drug Carriers / Q000737:chemistry*; D004339:Drug Compounding; D065546:Drug Liberation; D057927:Hydrophobic and Hydrophilic Interactions; D019344:Lactic Acid / Q000737:chemistry*; D016773:Leishmaniasis, Cutaneous / Q000188:drug therapy; D008536:Meglumine / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D000077485:Meglumine Antimoniate; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D009942:Organometallic Compounds / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D010316:Particle Size; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
chemical_list: D000981:Antiprotozoal Agents; D004337:Drug Carriers; D009942:Organometallic Compounds; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D008536:Meglumine; D000077485:Meglumine Antimoniate
keywords: Degradation rate; EDX; double emulsion; drug distribution; poly(lactide-co-glycolide)