PLGA Implants containing vancomycin and dexamethasone: development, characterization and bactericidal effects

Post-operative endophthalmitis is an infection and an inflammation of the eye following a surgical procedure. Its treatment is based on drug injections into the eye. However, this treatment can lead to ocular complications. Intraocular implants could substitute the conventional therapy. Poly(lactic-co-glycolic acid) (PLGA) implants comprising on vancomycin and dexamethasone were evaluated as drug delivery system to treat endophthalmitis after cataract surgery. Implants were characterized by drug content uniformity, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Wide Angle X-ray Scattering (WAXS), Scanning Electron Microscopy (SEM) and in vitro drug release. The bactericidal effect of vancomycin, eluted from the implants, was demonstrated against Staphylococcus aureus and Staphylococcus epidermidis. The drugs were uniformly distributed in the polymer. The analytical techniques revealed the chemical integrity of the drugs incorporated into the polymer and the modification of dexamethasone semi-crystalline nature. Drugs were controlled released from implants; and the eluted vancomycin showed bactericidal effects. In conclusion, PLGA implants containing vancomycin and dexamethasone may represent a therapeutic alternative to treat post-operative endophthalmitis.