Evaluation of solid state form of troglitazone by solid state NMR spectroscopy

Area of Science:

• Pharmaceutical Sciences
• Solid-State Chemistry
• Analytical Chemistry

Background:

• Characterizing solid-state forms of drug substances is critical for pharmaceutical development.
• Troglitazone's solid-state properties influence its bioavailability and stability.
• Distinguishing between different solid forms, including hydrates and amorphous states, is essential.

Purpose of the Study:

• To evaluate the utility of solid-state nuclear magnetic resonance (SSNMR) spectroscopy for characterizing troglitazone drug substance and its formulations.
• To compare the capabilities of SSNMR with powder X-ray diffractometry (PXRD) in solid-state analysis.
• To determine the solid-state form of troglitazone in pharmaceutical tablets and its stability.

Main Methods:

• Solid-state nuclear magnetic resonance (SSNMR) spectroscopy was employed.
• Powder X-ray diffractometry (PXRD) was used for comparative analysis.
• Characterization was performed on troglitazone drug substance, diastereomers, and formulated tablets.

Main Results:

• SSNMR clearly distinguished between hydrated and non-hydrated RR/SS forms of troglitazone, surpassing PXRD's resolution.
• SSNMR confirmed troglitazone drug substance exists as a physical mixture of diastereomers.
• SSNMR successfully characterized the amorphous solid state of troglitazone in tablets, unaffected by pharmaceutical additives, unlike PXRD.
• Troglitazone in tablets was found to be amorphous and remained so under heat and humidity stress.

Conclusions:

• SSNMR spectroscopy is a powerful tool for characterizing complex solid-state forms of drug substances and formulations.
• SSNMR offers superior capabilities compared to PXRD for analyzing troglitazone, especially in the presence of excipients.
• The findings highlight the importance of SSNMR in guiding the development of stable and effective pharmaceutical formulations for troglitazone.