Microparticle formation of sodium cellulose sulfate using supercritical fluid assisted atomization introduced by hydrodynamic cavitation mixer

A novel micronization technique so-called supercritical fluid assisted atomization introduced by hydrodynamic cavitation mixer (SAA-HCM) was used to produce the sodium cellulose sulfate (NaCS) microparticles with well-defined spherical morphologies and controlled particle size distributions in aqueous solution. The process parameters such as mixer temperature and pressure, the mass flow ratio, precipitator temperature, solution concentration and the molecular weight of NaCS were investigated in detail to evaluate their influences on the morphologies and size distributions of precipitates. Spherical NaCS particles with mean diameters ranging from 0.3 to 3.0 mu m were produced at the optimum operating conditions and narrow particle size distributions were obtained. It is natural to put forward the particle formation mechanism of deflated balloons. Compared with the unprocessed NaCS, there was no significant change on the primary structure and stability of the NaCS processed by SAA-HCM verified by Fourier transform infrared spectroscopy. The X-ray diffraction and thermo-gravimetric analysis were also used to investigate NaCS modifications and a slight change in crystalline state with higher thermal stability was observed when treated by SAA-HCM process. The results indicated that NaCS micronization by SAA-HCM process was expected to be a promising technique for drug delivery system. (C) 2010 Elsevier B.V. All rights reserved.