Liposomes containing dexamethasone: preparation, characteristics and application in ophthalmology

Abstract

Glucocorticoid dexamethasone (DM) liposomes of various lipid compositions were obtained. DM was used in insoluble form and in water-soluble form as disodium salt of dexamethasone phosphate (DMP). Correspondence between the drug inclusion percent and the structure of liposomes, and its solubility in water was studied. Lipids were shown to allow DM solubilization at concentration exceeding its solubility in water 9.3 times. Using repeated gel-chromatography, release of medicinal substances from liposomes was determined for all the samples of liposomes containing both DМP and DM. It was thus shown that up to 87% of the included substance remained in the liposomes. Biocompatibility of «empty» liposomes and liposomes containing a glucocorticoid with rabbit eyeball tissues was studied after their endovitreal incorporation. Dipalmitoylphosphatidylcholine liposomes were demonstrated not to cause inflammatory reaction after introduction in this way. Distribution of the liposomes in tissues of the rabbit eye posterior chamber was determined. It was shown that the liposomes after endovitreal introduction were distributed in various layers of retina.

Keywords

• liposomes
• ophthalmology
• phosphalipids
• glucocorticoids
• dexamethasone
• endovitreal introduction
• biocompatibility
• confocal microscopy