Rheological characteristics of drug-loaded microemulsions and their printability in three dimensional printing systems.

Rheological properties of microemulsions (MEs) and their printability in three dimensional printing (3DP) systems were investigated. A series of MEs with different contents of oil phase were prepared using sonication method with ibuprofen as model drug and soybean lecithin as emulfier. Stationary and transient rheological properties of MEs were investigated by ARES-SRF using concentric cylinders measuring systems. 3DP systems with piezoelectric drop-on-demand print heads were employed to test the printability of the MEs. Results demonstrate that the apparent viscosity and dynamic linear viscoelastic regions of the MEs are the most important parameters for continuous and stable printing of MEs by 3DP. The incorporation of drug in the MEs has little influence on the MEs’ stationary rheological behaviors and dynamic viscoelasticity, but the concentration of oil phase has a strong influence on them. The rheological property of binder liquids has a close relationship with their printability in 3DP system. [ABSTRACT FROM AUTHOR]