Protein based nanoparticles as platforms for aspirin delivery for ophthalmologic applications.

Most conventional ophthalmic dosage forms, though simplistic are limited by poor bioavailability in the posterior chamber of the eye. Application of nanotechnology has the potential to overcome this problem. By varying aspirin albumin ratios from 0.06 to 1.0, we obtained electrokinetically stable, pharmacologically active albumin based aspirin nanoparticles of <200 nm diameter with low polydispersity. In vitro release study showed nanoparticle formulation can release aspirin at a sustained rate for prolonged duration (90% at 72 h) and 11% drug release in the posterior chamber over a period of 72 h under simulated condition. Stability of the formulation was well maintained on storage for six months and after reconstitution for 24 h. The formulation showed no hemolysis in contrast to the high hemolysis due to the free drug. This study shows that aspirin loaded albumin nanoparticles prepared by coacervation holds promise as a formulation for topical delivery in diabetic retinopathy.