An improved processing technique that can be used to collect nanoparticles produced by the RESS process. The collection efficiency by almost an order of magnitude compared to the traditional collection processes. One process does not utilize any stabilizing solid co-solvents but produces similar effects using the supercritical solvent itself (e.g. CO2) as a stabilizing phase. Very small particles (diameter <；10 nm) with uniform size distribution and particulate suspensions thereof may be produced.
