Dually functional hollow ceria nanoparticle platform for intraocular drug delivery: A push beyond the limits of static and dynamic ocular barriers toward glaucoma therapy

Delivery of ophthalmic drugs to the interior parts of the eye for effective treatment of glaucoma (i.e., a chronic disease) remains a huge challenge because of the well-known static and dynamic ocular barriers. Herein, we present a new antiglaucoma formulation based on the development of a dual-functional therapeutic nanocarrier platform for intraocular targeted and sustained delivery of pilocarpine. Specifically, chitosan and ZM241385 are functionalized onto surfaces of hollow ceria nanoparticles (hCe NPs), thereby endowing the nanocarriers with a strong capability to open corneal epithelial tight junctions and deliver drug molecules to the targeted intraocular tissue (i.e., ciliary body). Moreover, the nanocarriers are demonstrated in vitro and in vivo to possess potent anti-oxidant and anti-inflammatory properties, which are beneficial to simultaneously alleviate glaucomatous damage. Single topical instillation of the pilocarpine-loaded dual-functional therapeutic nanocarriers with optimized delivery performance onto experimentally glaucomatous eyes can effectively mitigate disease progression for 7 days while that employing the traditional commercial eye drops only provides a moderate treatment efficacy for 4 h, possibly due to improved intraocular drug delivery (~250-fold greater bioavailability in the ciliary body) and intrinsic therapeutic activity of the ophthalmic formulation. These findings show great promise for the development of advanced nano eye drops toward efficient management of ocular diseases occurred in the inner segments of the eye.