Research on metastable zone of adenosine 5'-monophosphate in ethanol and water

Qualitative data on the solubility and supersolubility for binary system 5'-AMP + H₂O solution and ternary system 5'-AMP + H₂O + ethanol solution was determined at 293-323 K in the volume fraction ethanol range of 0.3-2.0, which were essential for solvent-out crystallization studies. The supersolubility of 5'-AMP fulfills well the empirical formula in both pure water and H₂O + ethanol solution. Temperature, ethanol addition rate, pH levels and rotate speed of stirrer were being recognized as nonvasive control parameter for adenosine 5'-monophosphate crystallization. The metastable zone was obtained under the conditions of temperatures, ethanol addition rate, pH levels and rotate speed of stirrer and estimated by using Central Composite Designs in the solvent-out crystallization process, and the variation of crystal habit of 5'-AMP was studied by scanning electron microscope after optimization of the crystallization process. All the results were important for the control of industrial crystallization of 5'-AMP.