Spectroscopy may be used to obtain in situ information in real time for studying crystallisation.
We studied the solution mediated transformation of theophylline from form1 (anhydrate) to the less soluble, more stable form2 (monohydrate) using ATR-UV-Vis, reflectance NIR, ATR mid-ir and Raman spectroscopies.
The results on the right show what information each technique reveals. The transformation only takes a few minutes so the rapid nature of molecular spectroscopy is ideally suited as a monitoring tool..