High throughput RESS processing of sub-10 nm ibuprofen nanoparticles

We report the results of our research on the RESS precipitation of molecular clusters of ibuprofen with four different surfactants and the effect of surfactant concentration on their size. Our custom designed, liquid N₂ cooled collection process of the molecular clusters embedded in "dry ice", resulted in yields of up to 80% (w/w). Sublimation of the 'dry ice' in deionized water resulted in dispersions of ibuprofen in water. These dispersions were found to be stable at room temperature, for up to six months, as confirmed by DLS and AFM characterizations. Solution casting of the dispersions on silicon and sapphire substrates resulted in high quality, "liquid like" viscous films as observed by optical microscopy and AFM. XRD and confocal Raman characterizations confirmed that the molecular clusters retained their chemical identity of ibuprofen. Besides its scientific importance, this invention is expected to open up new drug delivery platforms.