Data from: Zeolitic imidazolate frameworks (ZIF-8) as a carrier in a topical ocular delivery system for the treatment of ocular diseases

Current systems for topical ocular drug delivery enable non-invasive
administration of therapeutics to the eye but suffer from poor
permeability and bioavailability, limiting therapeutic efficacy.
Metal-organic frameworks are porous, crystalline materials that can serve
as drug delivery systems and may improve these shortcomings. In this
study, we explore the use of ZIF-8 as a representative metal-organic
framework for topical ocular drug delivery. ZIF-8 particles were prepared
via a simplified aqueous synthetic method and loaded with ovalbumin, a
model molecule to simulate anti-angiogenic proteins that are used to treat
retinal diseases. The physical properties of unloaded and loaded ZIF-8
were evaluated with a variety of spectroscopic, imaging, and desorption
techniques that confirmed successful loading with ovalbumin (>46%
loading capacity) without severe disruption to the structure of ZIF-8. In
a bulk solution, loaded ovalbumin is gradually released in a linear
fashion for up to 60 days. Loaded ZIF-8 applied to chicken eggs or bovine
eyes showed minimal to no levels of irritation, supporting our hypothesis
that ZIF-8 can be safely applied to ocular tissue. When applied to ex vivo
bovine eyes, loaded agents administered in ZIF-8 penetrate the sclera,
suggesting ZIF-8 may enhance permeability to intraocular tissue. These
results highlight the potential of ZIF-8 as a carrier in topical ocular
delivery systems and provide a crucial foundation to evaluate its efficacy
in topical ocular drug delivery using in vivo models.