Background: Retinal neovascularization (NV) is the leading cause of blindness in the majority
of ocular diseases. Several treatment approaches have been developed for retinal NV; of these
methods, instillation of nanoparticles into the conjunctival sac has shown potential for retinal NV
treatment because it does not cause physical damage and is easy to operate.
Methods: In this study, honokiol-loaded chitosan/sulfobutylether-β-cyclodextrin nanoparticles (HKCS-
NPs) were prepared for ophthalmic drug delivery systems. An inclusion complex of honokiol and
sulfobutylether-β-cyclodextrin was used to incorporated insoluble honokiol into chitosan nanoparticles,
which were prepared through ionotropic gelation.
Results: HK-CS-NPs featured a spherical surface with a narrow size distribution of polydispersity index
less than 0.250, a mean size range of 373–523 nm, a positive surface charge of +19.9 to +24.2 mV,
and an entrapment efficiency of 84.92%. In vitro release studies showed an initial burst release phase
and a sustained release phase of nanoparticles. Moreover, in vivo study showed that HK-CS-NPs exhibited
good ocular tolerability and could improve ophthalmic bioavailability of honokiol. In particular,
the maximum concentration of honokiol after administration of HK-CS-NPs was enhanced by 1.65
times compared with that after instillation of the honokiol suspension alone.
Conclusion: This study proposes HK-CS-NPs as a potential ophthalmic delivery system.