Abstract
Purpose: :
The aim of the study was to develop a new self-emulsified, transparent and stable nanosystem for delivering lipophilic topical ocular drugs.
Methods: :
Betamethasone Dipropionate, Latanoprost and Cyclosporine A were chosen as drugs. Active principle, Medium Chain Triglycerides (MCT) and Vitamin E TPGS were melted at 30-35°C to obtain a transparent oil that was added to a phosphate buffered aqueous solution containing Glycerin. No energy (homogenization, heating or high speed stirring) or organic solvent was required. Particle Size, Polydispersity Index, Z Potential, Encapsulation Percentage and Active principles concentrations were evaluated in order to characterize the formulations and to control their physical as well as chemical stability.
Results: :
The three formulations showed a Particle Size range of 10-30 nm, a Polydispersity Index of 0.05-0.1, a Z Potential of -8/-15 mV and 100% of Encapsulation Percentage. 0.05% Betamethasone Dipropionate (MDV BETA) and 0.05% Cyclosporine A (MDV CYCLO) formulations were physically and chemically stable at room temperature (25°C ± 2, RH 40%) and under refrigeration (2-8°C). 0.005% Latanoprost self-emulsified formulation (MDV LAT) was physically and chemically stable under refrigeration (2-8°C), at room temperature (25°C± 2, RH 40%) and at least two weeks at 70°C.
Conclusions: :
A new transparent self-emulsified drug delivery nanosystem has been prepared and optimized. This system characterized by very small Particle Size, very low Polydispersity Index and adequate Zeta Potential is able to guarantee a surprising long term physical as well as chemical stability to MDV BET, MDV CYCLO and MDV LAT formulations.
Keywords: development • anterior segment • cyclosporine