Boetker, J.Rades, T.Rantanen, J.Hawley, A.Boyd, B.J.2018-01-162018-01-162012Molecular Pharmaceutics, 2012; 9(9):2787-27911543-83841543-8392http://hdl.handle.net/2440/110321In situ elucidation of kinetics of solution-mediated phase transformations using direct structural determination has been achieved using synchrotron SAXS/WAXS radiation. Using theophylline as a model drug with known phase transformation from anhydrate to monohydrate form in aqueous conditions within a few minutes, the kinetics of the structural transition were resolved at the second scale, and the results achieved agreed well with those determined using indirect approaches such as Raman spectroscopy. The recrystallization of the monohydrate in situ (due to its lower solubility) from dissolved anhydrate solution (higher solubility) is demonstrated directly, highlighting a major issue for such compounds in application. The technique has the additional benefit of having the potential to identify intermediate structures which are not readily achievable with in situ spectroscopic techniques, as well as being amenable to high throughput approaches.en© 2012 American Chemical SocietyPolymorph; solvent; synchrotron SAXS; theophylline; kineticsJournal article003007808110.1021/mp30030720003082637000422-s2.0-84865959008346159Rades, T. [0000-0002-7521-6020]