Vibrational study of acetazolamide polymorphism

In this paper, an acetazolamide vibrational study has been conducted to identify its two known polymorphic forms (A and B). Other techniques, such as Hot-stage and X-ray powder diffraction, have been also reported. Moreover, the thermodynamic and spectroscopic behaviour of ground form A has been investigated.In this study, acetazolamide form A was ground at different times (1, 5, 10, 15, 20 min) and FT-IR/ATR and DSC measurements have been carried out. The grinding process, decreasing the particle sizes, has been induced a polymorphic transformation of A to B form.To determine the B in A percentages, calibration curves have been performed by FT-Raman measurements.