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Recrystallization of amorphous drugs is currently limiting the simple approach to improve solubility and bioavailability of poorly water-soluble drugs by amorphization of a crystalline form of the drug. In view of this, molecular mobility, α-relaxation and β-relaxation processes with the associated transition temperatures T_gα and T_gβ, was investigated using dynamic mechanical analysis (DMA). The correlation between the transition temperatures and the onset of recrystallization for nine amorphous drugs, stored under dry conditions at a temperature of 296 K, was determined. From the results obtained, T_gα does not correlate with the onset of recrystallization under the experimental storage conditions. However, a clear correlation between T_gβ and the onset of recrystallization was observed. It is shown that at storage temperature below T_gβ, amorphous nifedipine retains its amorphous form. On the basis of the correlation …