Background:
Captain encapsulation is one of the very first member of THE SUPERCRITICALS. Armed with the ability to remove harmful organic solvents effectively, Captain Encapsulation is committed to protect the weak and vulnerable with a layer of protection. (E.g. heat and oxidation sensitive ingredients can be microencapsulated in biocompatible coating material to provide stability and improve shelf life)
Action:
Microencapsulation by supercritical CO2 can be achieved by Supercritical Antisolvent (SAS) process or the supercritical Spray drying process.

In SAS, a solution of the coating material and active ingredient dissolved in a suitable organic solvent (e.g. ethanol, dichloromethane, ethyl acetate, etc) will be sprayed into supercritical CO2. The supercritical CO2 removes the bad guys (organic solvents) in a FLASH and the active ingredient is saved (co-precipitated out) in the CO2.
Opportunities:
Microencapsulation offers excellent opportunities for masking!

Taste masking, color masking or odor masking of active ingredients can help to improve consumer acceptance.
In addition, microencapsulation can also be applied for controlled delivery systems where a long-term or a trigger-controlled release (by pH or temperature) is desired. Applications in controlled release systems investigated include paclitaxel (a hydrophobic anticancer drug) in PLA and Curcumin in Eudragit L100 (Generous gift from Evonik Industries).

More information can be found in the references below:
- L Y Lee, C.H. Wang, K.A. Smith, “Supercritical antisolvent production of biodegradable micro- and nanoparticles for controlled delivery of paclitaxel”, Journal of Controlled Release, 125, 96-106 (2008).
- L Y Lee, KA Smith, C H Wang. Paclitaxel-loaded Poly L Lactide prepared by Supercritical Antisolvent methods. Singapore-MIT Alliance Annual Symposium, Singapore, Jan 2006
- L Y Lee, K A Smith, C H Wang. Nanoparticle fabrication of biodegradable polymers using supercritical antisolvent: Effects of mixing and thermodynamic properties. AICHE Annual Meeting, Ohio, USA, Nov 2005