Table 1.
Lipid-based nanocarriers for ocular delivery against herpes simplex virus keratitis.
| Objectives | Drug | Type of Formulation | Polymer Used | Membrane/Cell Line/Animal Model | Outcome | Source |
|---|---|---|---|---|---|---|
| To investigate the pharmacokinetics of acyclovir liposomes delivered to aqueous humour. | Acyclovir | Liposomes | Cholesterol, L-phosphatidylcholine, stearylamine | New Zealand (NZ) albino rabbits | Particle size: 370.9 ± 5.6 nm. Entrapment efficiency: 22.8%. Loading ACV concentration in liposome dispersion: 0.20 mg/mL. In vivo efficacy: 11-fold greater drug availability in the aqueous humour vs. reference ointment. In vitro release: higher drug release (50.25%). |
[40] |
| To develop and optimise formulations of transferrin-conjugated liposomes containing ganciclovir. | Ganciclovir | Liposomes | Cholesterol, 1,2- distearoyl-sn-glycero-3-phosphocholine (DSPC), 1,2- distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[maleimide (polyethylene glycol) − 2000] (DSPE-PEG-MAL) |
Human retinal pigment epithelial cells (ARPE-19) | Particle size: 88–113 nm. Zeta potential: ~−32 mV. Entrapment efficiency: 32–36%. In vitro release: prolonged drug release of over 12 h. In vivo efficacy: higher drug uptake by ARPE-19. In vitro cytotoxic (APRE-19): cell viability of 80–100% based on MTT assay. |
[42] |
| To evaluate the ocular retention and intraocular delivery of mucoadhesive niosomal ganciclovir. | Ganciclovir | Niosomes coated with chitosan | Cholesterol, Span 60, chitosan | NZ albino rabbits | Particle size: 190 nm. Zeta potential: +41.8 mV (successfully coated with cationic chitosan). Entrapment efficiency: 47.2%. In vitro release: sustained drug release over 12 h. In vivo efficacy: drug concentrations obtained in the aqueous humour of niosome-treated albino rabbits were significantly greater. In vivo irritation: no visual irritation or damaging effect to ocular tissues of tested rabbits. |
[43] |
| To fabricate and achieve efficient delivery of valacyclovir into the eye via solid lipid nanoparticles (SLNs). | Valacyclovir | SLNs | Stearic acid, tristearin, poloxamer 188, sodium taurocholate | Chorioallantoic membrane (CAM) | Particle size: 202.5 ± 2.56 nm. Zeta potential: −34.4 ± 3.04 mV. Entrapment efficiency: 58.82 ± 2.45%. In vitro release: sustained drug release over 12 h. In vivo efficacy: improved ocular bioavailability. Ex vivo irritation: no irritation in CAM and histopathology result. |
[45] |
| To improve the ocular bioavailability of acyclovir using SLN and nanostructured lipid carriers (NLC) delivery systems. | Acyclovir | SLNs and NLCs | Stearic acid, Capryol® 90 Lauroglycol® 90, Compritol® 888 ATO, and Cithrol GMS, Tween® 40, Tween® 80, Poloxamer® 188, Brij® 78 | Bovine cornea | Particle size: 185–766 nm. Zeta potential: −30 to 34 mV. Entrapment efficiency: 4–34%. In vitro release: Both NLCs and SLNs showed extended drug release (8 h) compared to the reference solution (4 h). Faster diffusion and release of drug from the NLCs. Hydration level: no signs of toxicity to the cornea based on hydration level test. |
[46] |
| To conduct an ex vivo and in vivo evaluation of chitosan-coated NLCs for acyclovir ocular delivery. | Acyclovir | NLCs | Lauroglycol® 90, Compritol® 888 ATO, Cithrol GMS, Tween® 40, chitosan |
Vero cells | In vivo efficacy: 3.5-fold reduction in effective concentration to achieve 50% inhibition of viral replication (IC50) was observed with acyclovir NLC-treated monkey kidney cells (CV-1). Acyclovir uptake by primary human corneal epithelial cells (HCEC) was higher in NLCs. In vitro cytotoxicity: MTT assay found no toxic effects on Vero cells. |
[47] |
| To develop and characterise a nanoemulsion of acyclovir as a topical gel. | Acyclovir | Nanoemulsion | Castor oil, Span 40, PEG 400 | - | Mean vesicle size: 41.6 nm. Zeta potential: −32.4 mV. Loading capacity: ~62–89%. In vitro release: 88% drug release within 8 h. |
[50] |