Evaluation of a new solid non-aqueous self-double-emulsifying drug-delivery system for topical application of quercetin.

This study aimed to the evaluation of a new solid non-aqueous self-double-emulsifying drug-delivery system (SDEDDS) for topical application of quercetin. The new formulation was prepared through two-step emulsification process and could spontaneously form oil-in-oil-in-water (O/O/W) double emulsions after dilution with aqueous medium, with inner oil phase mainly containing the drug. Solid state characterisation was performed by DSC and X-ray powder diffraction. Furthermore, the optimised QT-SDEDDS displayed sustained release profile and was found to be stable up to 30 days under 4 °C and 25 °C. Antioxidant capacities showed that quercetin could be protected by the solid non-aqueous SDEDDS. Compared with the quercetin ethanol aqueous solution, the QT-SDEDDS exhibited higher permeation ability, and significantly increased accumulation of quercetin in the skin. These studies demonstrated that the solid non-aqueous SDEDDS might be a promising carrier for topical application of poorly water-soluble and simultaneously poorly oil-soluble drugs, such as quercetin.

Industrialization of lipid nanoparticles: From laboratory-scale to large-scale production line.

This work aimed at developing a large-scale modular production line, which referred to coenzyme Q10 loaded-NLC as well as its continuous and scalable emulsification and homogenization process. The production line exhibited good control over the emulsification and homogenization process and enabled the particle size of NLC below 210nm at a throughput of 25kg/h (for lipid solution at a flow rate of 0.4kg/min). Among the several process parameters investigated, the size of the NLC was mainly influenced by the pre-emulsification temperature, homogenization pressure and homogenization. Suitable emulsification temperature (70°C), homogenization pressure (600, 800bar), and homogenization cycle (3, 4cycles) resulted in relatively smaller particles. These results proved that coenzyme Q10, a model active, had been successfully loaded into the NLC. Meanwhile, the large-scale production line can be effectively applied for continuous and modular production of NLC. The line had modern networking features-essential in the Internet age-and a modular design that was easily modified and upgraded. In addition, the long-term stability over 6month was monitored at 30°C and at 40°C to assess a potential effect of the laboratory scale and large scale on stability. All batches at room temperature and below were stable, and only a negligible increase in size was observed.