Supercritical antisolvent precipitation of salbutamol microparticles

The micronization of salbutamol has been tested by supercritical antisolvent precipitation to assess the possibility of producing microparticles with controlled particle size and distribution. Various liquid solvents have been used to find the solvent–solute couple suitable for optimum processing; supercritical CO2 has been used as the antisolvent. amol was tested using dimethylsulphoxide (DMSO), methyl alcohol and ethanol–water mixtures. Only when DMSO was used, was obtained a successful micronization. Various morphologies were observed on varying the precipitation pressure. The influence of liquid solution concentration on the dimensions of salbutamol particles was studied. The most interesting morphology consisted of rod-like particles of controlled length between 1 and 3 μm and diameters between 0.2 and 0.35 μm; these particles were obtained operating at 40°C and in the pressure range between 100 and 150 bar.