Polymorphic properties of micronized mefenamic acid, nabumetone, paracetamol and tolbutamide produced by rapid expansion of supercritical solutions (RESS)

Publication date: October 2016 Source:The Journal of Supercritical Fluids, Volume 116 Author(s): Michael Türk, Dennis Bolten The rapid expansion of a supercritical solution (RESS) process was used to produce submicron Paracetamol (=Acetaminophen), Mefenamic acid, Nabumetone and Tolbutamide particles. These model drugs have been chosen since different numbers of polymorphs (I & II, I–III and I–V) have been reported in literature. Thus, the aim of this investigation was twofold: to examine the possibility of using the RESS process to produce submicron drug particles and to control the polymorphic properties of drug micro-particles. The unprocessed and micronized particles are characterized by scanning electron microscopy, X-ray diffraction and differential scanning calorimetry. A significant reduction was observed in the particle size and size distribution of the particles produced by RESS. The mean particle size of the processed particles increased in the following order: Mefenamic acid (0.08μm≤ x50 ≤0.16μm)<Paracetamol (0.16μm≤ x50 ≤0.34μm)<Tolbutamide (0.34μm≤ x50 ≤0.45μm)<Nabumetone (0.75μm≤ x50 ≤0.81μm). Under certain temperature (333 and 353K) and pressure (15, 20, 25 and 30MPa) conditions, it was possible to form the favorable Tolbutamide polymorphic form II. Thus, this study demonstrates that the polymorphic characteristics of submicron Tolbutamide particles produced by RESS can be controlled by varyi...

Source: The Journal of Supercritical Fluids - July 4, 2016 Category: Chemistry Source Type: research