Factors Affecting the Formation of Sulfamethoxazole-trimethoprim Co-crystal
Drug co-crystal had a promising application in improving the solubility and dissolution of poorly water-soluble drugs.The compound sulfamethoxazole tablets contain two active pharmaceutical ingredients:sulfamethoxazole and trimethoprim,which may form co-crystal.In this paper,the existence of the co-crystal in the tablets had been confirmed by comparison with the standard samples.Then,three influence factors introduced in the formulation process,namely water content,pressure and temperature,on the formation of sulfamethoxazole-trimethoprim co-crystal was investigated.The results showed that water content was the key parameter for the formation of the co-crystal,whereas the co-crystal was formed only when the temperature reached above 128 ℃.Pressure was proved to have no effect on the formation of the co-crystal.The formed co-crystal had a stable crystal structure,which improved the compression resistance of the tablets.
sulfamethoxazoletrimethoprimco-crystalcompound sulfamethoxazole tabletantibacterial drug