Depth profiling of compression-induced disorders and polymorphic transition on tablet surfaces with grazing incidence...

Area of Science:

• Materials Science
• Pharmaceutical Science
• Crystallography

Background:

• Crystallographic disorders like amorphicity and defects impact drug dissolution rates.
• Understanding these disorders is vital for pharmaceutical formulation development.
• The precise correlation between crystal disorders and dissolution remains unclear.

Purpose of the Study:

• To analyze pharmaceutical tablets using grazing incidence X-ray diffraction (GIXRD).
• To investigate the effect of the compaction process on tablet surface crystallographic properties.
• To assess the potential of GIXRD in analyzing pharmaceutical materials.

Main Methods:

• Carbamazepine, tolbutamide, and chlorpropamide tablets were compacted under varying pressures.
• Grazing incidence angle X-ray diffraction was employed for analysis.
• Crystallographic properties were studied as a function of depth from the tablet surface.

Main Results:

• Compression induced surface disorder (amorphicity, small crystallite size, defects) in tolbutamide and chlorpropamide tablets.
• These changes diminished with depth and depended on compression pressure.
• Carbamazepine tablets showed compression-induced changes, but less dependent on depth or pressure.
• Partial phase transition occurred in chlorpropamide tablets, influenced by surface amorphization and texturization.

Conclusions:

• Grazing incidence X-ray diffraction is a valuable tool for studying surface crystallographic transformations in tablets.
• Compression pressure can induce significant changes in the crystalline structure of pharmaceutical tablet surfaces.
• GIXRD provides depth-profiling capabilities for characterizing these compression-induced effects.