Inkjet printing for control of pharmaceutical polymorphism
Polymorph selection of pharmaceuticals is critical for the performance and stability of medicines. In order to select the most appropriate polymorph for development, it is vital to be able to screen, isolate and characterise metastable crystalline forms. Inkjet printing offers much potential in this area, because the small volumes of drug solutions that can be jetted mean crystallisation occurs rapidly and in volumetric confinement. Here, the use of inkjet printing to isolate metastable forms of a number of pharmaceuticals will be discussed. Methods of characterisation of the printed crystals, including Raman spectroscopy and X-ray diffraction, will also be introduced.