Formulation and evaluation of polymer-coated bimatoprost-chitosan matrix ocular inserts for sustained lowering of IOP in rabbits

Abstract

Bimatoprost (BIM), a prostaglandin analog is a promising drug for treating glaucomic symptoms. However, Bimatoprost has short elimination half life in addition, the eye drops that are most prevalently sold on the market have a shorter ocular residence time; as a result, the drug has a poor bioavailability. The current study's goal was to create and test a promising sustained-release ocular insert for bimatoprost. By the solvent casting method BIM-chitosan matrix was prepared and the dried film was coated with Polycaprolactone (PCL)/PCL-PVA solution. Studies on swelling index, ATR-FTIR, drug content uniformity were used to characterise the inserts. SEM was used to observe surface morphology of uncoated insert, and PCL and PVP K 30 coated inserts. And thickness of the ocular insert (51 μm). In vitro studies were carried out using Franz diffusion cells. In vivo studies were conducted on healthy rabbits to examine changes in intraocular pressure (IOP), showed IOP of 15.9 mmHg for BIM-PCL insert and 14.6 mmHg for BIM-PVP insert at 120 h. This confirmed that the BIM inserts were able to have sustained reduction of IOP for a period of six days.