Dexamethasone acetate encapsulation into Trojan particles

J Control Release. 2008 May 22;128(1):41-9. doi: 10.1016/j.jconrel.2008.02.008. Epub 2008 Mar 4.

Abstract

We have combined the therapeutic potential of nanoparticles systems with the ease of manipulation of microparticles by developing a hybrid vector named Trojan particles. We aim to use this new delivery vehicle for intravitreal administration of dexamethasone. Initialy, dexamethasone acetate (DXA) encapsulation into biodegradable poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles was optimized. Then, Trojan particles were formulated by spray drying 1,2-Dipalmitoyl-sn-Glycero-3-Phosphocholine (DPPC), hyaluronic acid (HA) and different concentrations of nanoparticle suspensions. The effect of nanoparticles concentration on Trojan particle physical characteristics was investigated as well as the effect of the spray drying process on nanoparticles size. Finally, DXA in vitro release from nanoparticles and Trojan particles was evaluated under sink condition. SEM and confocal microscopy show that most of Trojan particles are spherical, hollow and possess an irregular surface due to the presence of nanoparticles. Neither Trojan particle tap density nor size distribution are significantly modified as a function of nanoparticles concentration. The mean nanoparticles size increase significantly after spray drying. Finally, the in vitro release of DXA shows that the excipient matrix provides protection to encapsulated nanoparticles by slowing drug release.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1,2-Dipalmitoylphosphatidylcholine / chemistry
  • Anti-Inflammatory Agents / chemistry*
  • Dexamethasone / analogs & derivatives*
  • Dexamethasone / chemistry
  • Drug Carriers / chemistry*
  • Excipients / chemistry
  • Hyaluronic Acid / chemistry
  • Lactic Acid / chemistry
  • Microscopy, Confocal
  • Microscopy, Electron, Scanning
  • Nanoparticles / chemistry*
  • Nanoparticles / ultrastructure
  • Particle Size
  • Polyglycolic Acid / chemistry
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Solubility

Substances

  • Anti-Inflammatory Agents
  • Drug Carriers
  • Excipients
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polyglycolic Acid
  • 1,2-Dipalmitoylphosphatidylcholine
  • Lactic Acid
  • Dexamethasone
  • Hyaluronic Acid
  • dexamethasone acetate