Cyclosporine release and distribution in ophthalmic emulsions determined by pulsatile microdialysis.

An in vitro release test based on pulsatile microdialysis (PMD) is presented for the purpose of measuring the release of cyclosporine from ophthalmic emulsions, along with a method to determine the drug distribution within the oil-rich globule, surfactant-rich micelle and aqueous phases of the emulsion formulation. Compositionally equivalent formulations containing 0.05% cyclosporine were prepared with similar physical parameters (globule size, viscosity, surface tension zeta potential, osmolality, pH) but made with different manufacturing conditions.

An improved method for the characterization of supersaturation and precipitation of poorly soluble drugs using pulsatile microdialysis (PMD).

In current pharmaceutical drug discovery, most candidates are poorly soluble in water, which can result in poor bioavailability. To overcome this problem, formulations that create supersaturation of the drug are a well-studied alternative. Characterizing the dissolution from these systems is challenging because conventional methods, such as sampling with a syringe then filtering with a 0.