THz-TDS transflection measurements as a process analyser for tablet mass

Area of Science:

• Pharmaceutical Technology
• Analytical Chemistry
• Spectroscopy

Background:

• Tablet content uniformity is critical for drug efficacy and market release.
• Current methods for controlling tablet mass lack robustness, sensitivity, and speed.
• Process analytical technology (PAT) is essential for real-time pharmaceutical manufacturing control.

Purpose of the Study:

• To investigate terahertz time-domain spectroscopy (THz-TDS) as a process analytical tool for tablet mass measurement.
• To assess the feasibility of using THz-TDS for in-line monitoring of tablet physical attributes.
• To explore the potential of THz-TDS for simultaneous measurement of tablet mass and height.

Main Methods:

• Utilized terahertz time-domain spectroscopy (THz-TDS) in a reflection setup to analyze tablets.
• Measured the time delay of frontside reflection and backside transflection signals.
• Correlated the time delay of the backside transflection with tablet mass.

Main Results:

• An increase in tablet mass directly correlated with an increased time delay of the backside transflection signal.
• Achieved root mean squared errors of approximately 1 mg for tablet mass determination.
• Demonstrated the potential for high acquisition rates (50 Hz) for rapid analysis.
• Showcased simultaneous measurement of tablet height using frontside reflection.

Conclusions:

• THz-TDS is a viable and sensitive method for indirect tablet mass measurement.
• The technique enables in-line monitoring of tablet mass and height, supporting content uniformity strategies.
• This methodology facilitates real-time control of the tablet compression process based on physical attributes.