بهبود خصوصیات فیزیکو مکانیکی برخی داروها و اکسی پیان ها به روش کریستالیزاسیون کروی

Abstract

One of the crystal growth processes is the production of crystal agglomerates by spherical crystallization. Agglomerates of materials were developed by means of spherically agglomeration (Carbamazepine) and emulsion solvent diffusion (Naproxen and Lactose) spherical crystallization techniques. The flow and packing properties of agglomerates represented in terms of the angle of repose and change in tapping density. Scanning electron microscopy, X-ray powder diffraction, FT-IR spectrophotometry and differential scanning calorimetry were used to investigate the physical characteristics of resulting crystals. The dissolution behavior (Naproxen and Carbamazepine) and compaction properties under various compression pressures were also studied. To optimize spherical crystallization of materials, in each case some parameters were considered. Naproxen was crystallized from acetone (solvent)-water (nonsolvent) in the presence of different concentrations of hydroxypropylcellulose (HPC). The spherical crystal agglomeration of lactose was carried out by non-solvent method, the solvent was water and nonsolvent was ethanol. The operation parameters of the experiment were the flow rate of ethanol, the temperature difference between solvent and nonsolvent and solvent/nonsolvent ratio.A three solvent system included ethanol (good solvent), water (poor solvent) and isopropyl acetate (bridging liquid) was utilized to produce the spherical agglomeration of Carbamazepine. The difference in temperature between good solvent and poor solvent and stirring rate during crystallization were considered as operation parameters.The flow and packing properties of agglomerates were much improved by this technique compared with those of conventional crystals due to the increase in particle size, spherical shape and smooth surface. Agglomerates were compressed to compacts which had considerable hardness without capping. The excellent compactibility of the agglomerates was attributed to the fragmentation property. In conclusion, the micromeritic properties of agglomerated crystals, such as flowability, packability and compactibility were improved profoundly resulting in successful direct tabletting without capping.