Nanomedicine for glaucoma: liposomes provide sustained release of latanoprost in the eye

Int J Nanomedicine. 2012;7:123-31. doi: 10.2147/IJN.S25468. Epub 2012 Jan 5.


Purpose: To report the development and therapeutic evaluation of a liposomal nanocarrier for sustained release of latanoprost, in the rabbit eye.

Methods: We fabricated latanoprost-loaded egg-phosphatidylcholine (EggPC) liposomes using the film hydration technique. The delivery vehicles were nano-sized (Z avg = 109 ± 18 nm), had a narrow poly dispersity index (PDI = 0.19 ± 0.04), and a very high loading efficiency (94% ± 5%). Based on in vitro data, we evaluated this formulation for lowering intraocular pressure (IOP) in rabbit eyes. Following a single subconjunctival injection of the latanoprost loaded formulation, the eyes were clinically monitored and the IOP recorded.

Results: Latanoprost-loaded EggPC liposomes demonstrated a high drug/lipid mole ratio of 0.181, remained stable for at least 6 months on storage (4°C), and at least 1 month at 25°C. A slow and sustained release of 60% of latanoprost was achieved by 14 days in the in vitro release study. The same formulation demonstrated a greater sustained IOP lowering effect compared with daily administration of topical latanoprost beyond 90 days (4.8 ± 1.5 vs 2.5 ± 0.9 mmHg; P < 0.001). No signs of inflammation were evident in the eyes from slit-lamp examination analysis.

Conclusion: The loading required for a long-term sustained delivery of latanoprost for up to 90 days in the rabbit eyes was achieved with EggPC liposomes. A single injection of latanoprost-loaded EggPC liposomes can lower the IOP for up to 90 days, with a greater IOP lowering effect than daily topical administration of latanoprost.

Keywords: EggPC; glaucoma; latanoprost; nanoliposomes; nanomedicine; sustained ocular delivery.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Ophthalmic
  • Analysis of Variance
  • Animals
  • Antihypertensive Agents / administration & dosage
  • Antihypertensive Agents / chemistry
  • Antihypertensive Agents / pharmacokinetics
  • Delayed-Action Preparations
  • Drug Stability
  • Eye / metabolism
  • Female
  • Glaucoma / drug therapy*
  • Glaucoma / metabolism
  • Injections, Intraocular
  • Intraocular Pressure / drug effects
  • Latanoprost
  • Liposomes / administration & dosage
  • Liposomes / chemistry
  • Nanomedicine / methods*
  • Particle Size
  • Phosphatidylcholines / administration & dosage
  • Phosphatidylcholines / chemistry
  • Phosphatidylcholines / pharmacology
  • Prostaglandins F, Synthetic / administration & dosage*
  • Prostaglandins F, Synthetic / chemistry
  • Prostaglandins F, Synthetic / pharmacokinetics
  • Rabbits


  • Antihypertensive Agents
  • Delayed-Action Preparations
  • Liposomes
  • Phosphatidylcholines
  • Prostaglandins F, Synthetic
  • Latanoprost