Micronisation of carbamazepine through rapid expansion of supercritical solution (RESS)

► Experimental SLG data for CO2 / carbamazepine were measured according to the first melting point method. For this system, the melting temperature decreases from 460 K at 0.1 MPa continuously to 434 K at 20 MPa while the temperature increases from 436 K at 30 MPa to 447 K at 35 MPa. ► The solubility of carbamazepine in CO2 increases from 1.4 × 10−5 mol/mol at 15 MPa and 323 K up to 5.3 × 10−5 mol/mol at 30 MPa and 343 K. ► The RESS process is successfully applied to produce submicron carbamazepine particles in the range from 0.43 to 0.9 μm which is at least up to 29 times smaller than the unprocessed material. ► The study demonstrates that pure C-monoclinic carbamazepine particles can be produced for pre-expansion temperatures ≥ 363 K. ► Dissolution studies demonstrate that the dissolution rate coefficient of submicron carbamazepine was up to 2 times higher than that of the unprocessed material.