Browsing by Subject "fysikaalinen säilyvyys"

Indomethacin is a poorly soluble but highly permeable drug, and its biological availability can be improved by enhancing its solubility. In this study, co-crystals and co-amorphous systems of indomethacin and nicotinamide were prepared in a 1:1 molar ratio, which have previously been shown to enhance the solubility of indomethacin. It has also been observed that the co-amorphous indomethacin-nicotinamide system crystallizes into a co-crystal during storage. This study aimed to further investigate the properties, solubility, and stability of these compounds, and tablet formulations were also prepared from the co-crystal and co-amorphous systems. Powdered co-crystals and co-amorphous systems, as well as tablets prepared from them, were stored at 25°C with 60% relative humidity and at 40°C with 75% relative humidity, and their solubilities were studied for 12 weeks. The stability of the samples was also examined using Fourier infrared spectroscopy and differential scanning calorimetry over the same period, and changes in the physical properties of the tablets were monitored throughout the study period. Additionally, the effect of HPMC on the prevention of indomethacin recrystallization was investigated. Both the co-amorphous and co-crystalline forms were found to enhance the solubility of indomethacin in both powder and tablet formulations in this study. The co-crystal was stable, with no changes observed in its crystal structure or solubility over the 12-week study period. However, handling the co-amorphous material turned out to be difficult due to its low glass transition temperature of 19.68°C, causing the powder to soften at room temperature. During storage, it was shown to crystallize into a co-crystal, but its solubility properties were weaker to those of the actual co-crystal. None of the solubility tests showed evidence of indomethacin recrystallization, so the potential effect of HPMC on this phenomenon could not be determined in the study. Warmer and more humid conditions were found to increase the tensile strength of the tablets, resulting in slower dissolution.