Dixit M, Kini A G, Kulkarni P K
Department of Pharmaceutics, JSS College of Pharmacy, JSS University, S.S Nagar, Mysore-570015, India.
Res Pharm Sci. 2010 Jul;5(2):89-97.
Piroxicam, an anti-inflammatory drug, exhibits poor water solubility and flow properties, poor dissolution and poor wetting. Consequently, the aim of this study was to improve the dissolution of piroxicam. Microparticles containing piroxicam were produced by spray drying, using isopropyl alcohol and water in the ratio of 40:60 v/v as solvent system, and spray chilling technology by melting the drug and chilling it with a pneumatic nozzle to enhance dissolution rate. The prepared formulations were evaluated for in vitro dissolution and solubility. The prepared drug particles were characterized by scanning electron microscopy (SEM), differential scanning calorimeter, X-ray diffraction and Fourier transform infrared spectroscopy. Dissolution profile of the spray dried microparticles was compared with spray-chilled microparticles, pure and recrystallized samples. Spray dried microparticles and spray chilled microparticles exhibited decreased crystallinity and improved micromeritic properties. The dissolution of the spray dried microparticle and spray chilled particles were improved compared with recrystallized and pure sample of piroxicam. Consequently, it was believed that spray drying of piroxicam is a useful tool to improve dissolution but not in case of spray chilling. This may be due to the degradation of drug or variations in the resonance structure or could be due to minor distortion of bond angles. Hence, this spray drying technique can be used for formulation of tablets of piroxicam by direct compression with directly compressible tablet excipients.
吡罗昔康是一种抗炎药物，其水溶性和流动性较差，溶解性能和润湿性也不佳。因此，本研究的目的是提高吡罗昔康的溶出度。采用喷雾干燥法制备含吡罗昔康的微粒，以体积比40:60的异丙醇和水作为溶剂体系，并采用喷雾骤冷技术，即将药物熔融后通过气动喷嘴骤冷，以提高溶出速率。对所制备的制剂进行体外溶出度和溶解度评价。通过扫描电子显微镜（SEM）、差示扫描量热法、X射线衍射和傅里叶变换红外光谱对所制备的药物颗粒进行表征。将喷雾干燥微粒的溶出曲线与喷雾骤冷微粒、纯品及重结晶样品的溶出曲线进行比较。喷雾干燥微粒和喷雾骤冷微粒的结晶度降低，微观粉体学性质得到改善。与吡罗昔康的重结晶样品和纯品相比，喷雾干燥微粒和喷雾骤冷微粒的溶出度有所提高。因此，认为喷雾干燥是提高吡罗昔康溶出度的一种有用方法，但喷雾骤冷则不然。这可能是由于药物降解、共振结构变化或键角微小畸变所致。因此，这种喷雾干燥技术可用于通过与直接可压片辅料直接压片来制备吡罗昔康片剂。
