7.2.3 Polyethylene glycol (PEG) conjugated (PEGylated) solid lipid nanoparticles

Ketoconazole (KTZ) is a broad spectrum antifungal agent, with high liposolubility [71] but a short ocular half-life (elimination half-life is 19 min in aqueous humor and 43 min in cornea) [72] and very poor solubility (0.04 mg/ml). Ketoconazole (KTZ) loaded PEGylated SLNs were developed for targeted delivery of KTZ to the posterior part of the eye for treatment of fungal infection. It showed higher bioavailability both in the aqueous and vitreous humor with significant antifungal potential. The ex vivo corneal permeation study revealed higher corneal permeability of the PEGylated KTZ-SLNs. The developed SLN was satisfying various parameters suitable for ocular delivery such as pH, osmolarity, stability, autoclavability, particle size, preservation against contamination. The SLNs were found to be stable in terms of entrapment efficiency and total drug content at 2–8°C for 12 months. Thus it could be helpful in the treatment of keratitis and endophthalmitis [73].

List of SLNs and their different ligand conjugated forms for eye targeting have been summarized in Table 5.
