Newly discovered active pharmaceutical ingredients are mostly poorly water-soluble, resulting in low bioavailability when administered orally. One of the methods to enhance their bioavailability is transformation into solid dispersions, which we manufactured using an infrared heater. Using carvedilol and two mesoporous carriers (Neusilin®US2 and Aeroperl®300), we prepared binary mixtures to create solid dispersions using melting technique. First, we analyzed the solid dispersions by varying the heating time at a constant heating temperature of 140°C and a constant ratio between carvedilol and the carrier, 1:1 (w/w). We then proceeded to vary the temperature at a constant heating time of 150 seconds and a constant ratio of 1:1 (w/w) between carvedilol and the carrier. The final analyses in this set were performed at a constant temperature of 190°C and a constant heating time of 150 seconds. Here, we varied the ratios of binary mixtures to 1:5, 1:3, 1:2, 1:1, 2:1, and 3:1 (w/w) between carvedilol and the carrier. We conducted a differential scanning calorimetry analysis to determine the degree of crystallinity of carvedilol based on the measured melting enthalpy. We analyzed the decomposition of carvedilol using thermogravimetric analysis, performed dissolution testing, used UV-VIS spectroscopy to determine the content of carvedilol in solid dispersions, and calculated the percentage of dissoluted carvedilol. Additionally, we studied the particle surfaces with scanning electron microscope imaging. The most important test in our research was the dissolution test, in which we aimed to simulate conditions in the body by studying the release rate of solid dispersions in a medium with a pH of 6.8 at 37°C ± 0.5. Through this study, we determined the amount of carvedilol released from the solid dispersion and whether the creation of solid dispersions improved the water solubility of it. We found that the best conditions for producing solid dispersions were a heating time of 150 seconds and a heating temperature of 190 °C, we observed that the lower the melting enthalpy, the faster and more extensive the dissolution of carvedilol was. We also noted that dissolution was most influenced by the ratios in the binary mixtures. A higher portion of carvedilol resulted in fuller pores in the carrier, which reduces specific surface and thus the rate and extent of dissolution. Comparing both carriers, we found that Aeroperl®300 was a better carrier for producing solid dispersions in the infrared heater.
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