**How Does the CO2 in Supercritical State A**ff**ect the Properties of Drug-Polymer Systems, Dissolution Performance and Characteristics of Tablets Containing Bicalutamide?**

**Agata Antosik-Rogóz˙ 1,\*, Joanna Szafraniec-Szcz ˛esny 1,2, Krzysztof Chmiel 3, Justyna Knapik-Kowalczuk 3, Mateusz Kurek 1, Karolina Gawlak 2, Vittorio P. Danesi 4, Marian Paluch 3 and Renata Jachowicz 1**


Received: 8 June 2020; Accepted: 22 June 2020; Published: 25 June 2020

**Abstract:** The increasing demand for novel drug formulations has caused the introduction of the supercritical fluid technology, CO2 in particular, into pharmaceutical technology as a method enabling the reduction of particle size and the formation of inclusion complexes and solid dispersions. In this paper, we describe the application of scCO2 in the preparation of binary systems containing poorly soluble antiandrogenic drug bicalutamide and polymeric excipients, either Macrogol 6000 or Poloxamer®407. The changes in the particle size and morphology were followed using scanning electron microscopy and laser diffraction measurements. Differential scanning calorimetry was applied to assess thermal properties, while X-ray powder diffractometry was used to determine the changes in the crystal structure of the systems. The dissolution of bicalutamide was also considered. Binary solid dispersions were further compressed, and the attributes of tablets were assessed. Tablets were analyzed directly after manufacturing and storage in climate chambers. The obtained results indicate that the use of supercritical CO2 led to the morphological changes of particles and the improvement of drug dissolution. The flowability of blends containing processed binary systems was poor; however, they were successfully compressed into tablets exhibiting enhanced drug release.

**Keywords:** Bicalutamide; Poloxamer® 407; Macrogol 6000; supercritical carbon dioxide; solid dispersions; dissolution rate; amorphization
