Drug Nano-Particles Formation by Supercritical Rapid Expansion Method; Operational Condition Effects Investigation

Dissolution pressure and nozzle temperature effects on particle size and distribution were investigated for RESS (Rapid Expansion of Supercritical Solution) process. Supercritical CO۲ was used as solvent and Ibuprofen was applied as the model component in all runs. The resulting Ibuprofen nano-particles (about ۵۰ nm in optimized runs) were analyzed by SEM and laser diffraction particle size analyzer systems. Results show that in low supercritical pressure ranges, depending on the solvent and solid component properties (Lower than ۱۰۵ bar for Ibuprofen-CO۲ system), nozzle temperature should be as low as possible (۸۰-۹۰˚C for Ibuprofen-CO۲ system). In the other hand in high supercritical pressure ranges (above ۱۰۵ bar), high nozzle temperatures work better. The border line of these two areas depends on the solvent phase behavior. Rapid Expansion of Supercritical Solution into a liquid solvent (RESOLV) was also studied with and without the presence of surfactant and compared with RESS process by measuring of formed particles size, size distribution and dissolution rate. Results show that the RESS process generally creates better conditions for achieving fine and uniform organic powders (with mean particles size of ۴۰-۱۸۰ nm), in contrast to the RESOLV method (minimum particles size of ۸۰-۴۰۰ nm).

کلیدواژه ها:

Supercritical ، Rapid expansion ، Dissolution rate ، Mean particle size ، Size Distribution