title: Liquid crystalline coated drug particles as a potential route to long acting intravitreal steroids.
abstract: The aim of this study was to investigate the potential for coating drug particles with liquid crystalline lipids with a view to modifying drug dissolution behaviour in the particle form. Firstly, dissolution of a simple salicylic acid layer on a microscope slide, as a model system was shown to be hindered by the liquid crystal layer and was sensitive to the type of liquid crystal nanostructure present. Particles of sodium salicylate (hydrophilic) and triamcinolone acetonide (hydrophobic) were produced, and lipids applied to the drug surface using either mechanofusion or co-spray drying approaches. The coated sodium salicylate particles dissolved extremely rapidly. Triamcinolone acetonide particles on the other hand dissolved very slowly compared to uncoated triamcinolone acetonide particles, which indicated that the coating was in fact intact, and that drug solubility in the aqueous channels likely controlled the transport of drug into the dissolution medium. Whilst more investigation is required, these initial studies demonstrate a potentially useful strategy for controlling drug dissolution for applications such as intravitreal steroid injections.
authors.affiliation: Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, Victoria 3052, Australia.
authors.forename: Adam
authors.initials: A
authors.lastname: Tilley
authors.forename: David A V
authors.initials: DA
authors.lastname: Morton
authors.forename: Tracey
authors.initials: T
authors.lastname: Hanley
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Boyd
mesh_terms: D000893:Anti-Inflammatory Agents / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods; D003460:Crystallization; D003692:Delayed-Action Preparations; D057927:Hydrophobic and Hydrophilic Interactions; D020156:Salicylic Acid / Q000737:chemistry*; D012980:Sodium Salicylate / Q000737:chemistry*; D012995:Solubility; D014222:Triamcinolone Acetonide / Q000737:chemistry*; D014822:Vitreous Body / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D003692:Delayed-Action Preparations; D014222:Triamcinolone Acetonide; D020156:Salicylic Acid; D012980:Sodium Salicylate