DISSOLUTION BEHAVIOR OF 17-BETA-ESTRADIOL (E2) FROM POVIDONE COPRECIPITATES - COMPARISON WITH MICROCRYSTALLINE AND MACROCRYSTALLINE E2

The dissolution rates of macrocrystalline 17β-estradiol (E2), microcrystalline E2and E2-povidone coprecipitates and physical mixtures varying in weight ratio from 1 : 1 to 1:49 were determined at 37°C. E2 dissolution from the coprecipitates was markedly faster than that from either macro- or microcrystalline forms of the drug and was found to increase with decreasing E2-to-povidone weight ratio. Based on the results of X-ray diffraction, differential scanning calorimetric. Raman spectroicopic, and thermal gravi metric analysis studies, it is concluded that the formation of a more water soluble, high energy state of E2 is responsible for the increased dissolution rate of this natural cstrogen from low weight ratio povidone coprecipitates. These findings suggest that the use of E2-povidone coprecipitates may increase the systemic availability of E2. © 1979.