Table 2.

Polymeric-based nanocarriers for ocular drug delivery against herpes simplex virus keratitis.

Objectives	Drug	Type of Formulation	Polymer Used	Membrane/Cell Line/Animal Model	Outcome	Source
To evaluate the solubility of acyclovir, corneal permeability, and sclera penetration of Soluplus and Solutol polymeric micelles.	Acyclovir	Polymeric micelle	Soluplus® (polyvinyl co- prolactam-polyvinyl acetate-polyethylene glycol copolymer)	Chorioallantoic membrane (CAM)	Particle size: 219 nm. Zeta potential: +0.35 mV. Encapsulated acyclovir solubility: 2-fold in both water medium and phosphate-buffered saline (PBS) compared to unencapsulated acyclovir. In vivo permeability: 2.8-fold and 3.4-fold higher permeability flux than aqueous acyclovir in both cornea and sclera. In vitro irritation: no toxicity in fertilised eggs.	[54]
To develop a clear aqueous nanomicelle formulation and evaluate its biocompatibility.	Biotinylated lipid prodrug of acyclovir	Surfactant nanomicelle	D-α-tocopheryl polyethylene glycol 1000 succinate (Vitamin E TPGS) and octoxynol-40	Human corneal epithelial cells (HCECs)	Particle size: 10.78 nm. Zeta potential: −1.59 mV. Entrapment efficiency: ~90%. In vitro release: showed sustained release properties for up to 4 days. In vitro ocular irritation: no cytotoxic effect in HCECs.	[58]
To validate the effect of acyclovir concentration on the physicochemical characteristic and release profile of chitosan nanoparticles.	Acyclovir	Polymeric nanosuspension	Chitosan and Tween-80	-	Particle size: 200 ± 30 nm. Zeta potential: +36.7 ± 1.5 mV. Encapsulation efficiency: 56%. Loading capacity: 25%. In vitro release: release for up to 24 h.	[64]
To validate the effect of chitosan concentration on the physicochemical characteristic and release profile of chitosan nanoparticles.	Acyclovir	Polymeric nanosuspension	Chitosan and Tween-80	-	Particle size: 250 nm. Zeta potential: +42.8 mV. Encapsulation efficiency: 90%. Loading capacity: 50%. In vitro release: release for up to 24 h.	[65]
To increase ocular bioavailability of acyclovir through poly (lactic-co-glycolic acid) (PLGA)-based nanoparticles stabilised with vitamin E TPGS.	Acyclovir	Polymeric nanosuspension	PLGA and vitamin E TPGS	Albino rabbits	Particle size: 262.38 ± 11.85 nm. Zeta potential: 15.14 ± 2.81 mV. Encapsulation efficiency: 74.12 ± 6.19%. Loading capacity: 8.65 ± 1.09%. In vitro release: showed sustained release for up to 72 h. In vivo permeability: 1.4-fold higher permeability flux compared to drug solution. In vivo distribution: bioavailability was 2.76-fold higher than drug solution. In vivo ocular irritation: demonstrated mild irritation but subsided after 6 h.	[66]