title: In vitro evaluation of polymeric matrix and porous biodegradable reservoir devices for slow-release drug delivery.
abstract: OBJECTIVE
  Biodegradable polymeric devices were evaluated in vitro for intravitreal drug delivery.
  
  
  METHODS
  The matrix (short-term drug delivery) and the porous (longer-term drug delivery) reservoir devices were made from polycaprolactone of two molecular weights (30,000 and 56,000). Matrix devices were loaded with 5-fluorouracil or ganciclovir. Porous reservoirs were loaded with 5-fluorouracil, ganciclovir, 5-carboxyfluorescein, or foscarnet. The release was monitored in phosphate-buffered solution using ultraviolet spectrophotometry.
  
  
  RESULTS
  Release from the matrix devices was characterized by an initial burst, followed by a nonlinear release. The porous reservoirs demonstrated zero order linear release of drugs, sustained up to 250 days in this experiment.
  
  
  CONCLUSIONS
  The matrix device is capable of sustained release over several months; the porous reservoir can deliver drugs for over 1 year. Further studies are needed to evaluate in vivo biodegradation behavior and toxicity of drugs used for sustained release.
authors.affiliation: LSU Eye Center, Louisiana State University Medical Center School of Medicine, New Orleans, USA.
authors.forename: G A
authors.initials: GA
authors.lastname: Peyman
authors.forename: D
authors.initials: D
authors.lastname: Yang
authors.forename: B
authors.initials: B
authors.lastname: Khoobehi
authors.forename: M H
authors.initials: MH
authors.lastname: Rahimy
authors.forename: S Y
authors.initials: SY
authors.lastname: Chin
mesh_terms: D000998:Antiviral Agents / Q000493:pharmacokinetics*; D001673:Biodegradation, Environmental; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems / Q000295:instrumentation*; D005452:Fluoresceins / Q000493:pharmacokinetics*; D005472:Fluorouracil / Q000493:pharmacokinetics*; D017245:Foscarnet / Q000493:pharmacokinetics*; D015774:Ganciclovir / Q000493:pharmacokinetics*; D066298:In Vitro Techniques; D008855:Microscopy, Electron, Scanning; D011091:Polyesters; D016062:Porosity
chemical_list: D000998:Antiviral Agents; D003692:Delayed-Action Preparations; D005452:Fluoresceins; D011091:Polyesters; C016240:polycaprolactone; D017245:Foscarnet; C045132:4-carboxyfluorescein; D015774:Ganciclovir; D005472:Fluorouracil