Ultrasound-assisted theophylline polymorphic transformation: Selective polymorph nucleation, molecular mechanism and kinetics analysis

Abstract

Graphical abstract

New Case of Pharmaceutical Solid-State Forms: Several Novel Solvates/Polymorphs of Nilotinib and Their Phase Transformation Controls

“…It was observed that both the portion of water and the temperature of the SMPT experiments determined the results collected. A transformation from amorphous to other polymorphs or solvates by SMPT involves two processes, namely the dissolution of amorphous and the nucleation of the new solid-state phases. , Tables and indicate that as the water activity of MeOH/H 2 O and THF/H 2 O solutions increased and the temperature decreased, the solubility of nilotinib decreased consequently (the solubility curves and data could be found in Figures S7, S8 and Tables S14, S15, respectively) and became the rate-limiting step of the process, thus slowing down the transformation. In contrast, the decreased water activity would increase the solubility but inhibit the formation of hydrate form H3.…”

Ultrasound-assisted separation and crystallization of metacetamol polymorphs

“…This, in turn, has a potential impact on the ability to process, manufacture, bioavailability, stability, and efficacy of the drug product. [1][2][3] Therefore, pharmaceutical solid polymorphism has to be investigated throughout the stages of drug development.…”

Polymorph control by designed ultrasound application strategy: The role of molecular self-assembly

“…So researchers have tried to design polymorph control strategies to obtain specific crystallization outcomes. Designed methods appeared, for instance: template-induced crystallization [16] , [17] , magnetic-induced crystallization [18] , ionic liquid-induced crystallization [19] , ultrasonic-induced crystallization [20] , [21] , [22] , [23] , [24] , [25] , and nanoconfinement crystallization [26] , [27] . Among them, introducing ultrasound in the process of crystallization has been widely applied as an effective means of nucleation outcomes control.…”

“…Other studies confirmed that ultrasound could regulate the polymorphs at the nucleation stage by altering the nucleation kinetics of different polymorphs [25] , [30] , [31] . Fang [22] found that the ultrasound could provide enough energy to overcome the critical energetic barrier for nucleation, and eventually promote spontaneous nucleation of theophylline form V. Kaur Bhangu [25] and Ike [24] found that the cavitation effect generated by ultrasound can reduce the induction time and increase supersaturation, which tends to promote the nucleation of metastable form. Ultrasound could regulate the polymorphs of some organic compounds, however, this method is not always effective for all compounds in nucleation control [36] , [37] , [38] .…”