Thermal Analysis of Pharmaceuticals

The sample used was indium of calibration standard, purity > 99.999 percent.

Application

Standard application for calibration

Conditions

Measuring cell: DSC821^E

Pan: Aluminum 40 μl with a predrilled hole in the lid

Sample preparation: Indium pellet which is pressed flat, and premelted

DSC measurement: Heating was carried out from 120 °C to 180 °C at 10 K/min

Atmosphere: Nitrogen 50 cc/min

Interpretation

The DSC curve shows the melting pattern of indium, which like other pure metals melts at a clearly defined temperature called its melting point. This is considered the very beginning of the melting process which is denoted by the temperature at the point where the extrapolated slope of the melting curve intercepts the extension of the baseline.

Evaluation

This experiment determined the onset of melting (onset temperature) and heat of fusion of indium. This was a fully automated experiment and it performs a validation by making a comparison between the values obtained with each measurement and the published ones. If the measured values fall within acceptable limits the unit displays the message: “The DSC module is within specifications.”

Conclusion

The Indium check method is a rapid and easy way to evaluate the temperature and heat flow calibration of an instrument. The validation is carried out by automatic comparison of the results with the reference values. If instrument adjustment is needed, the display shows a message to this effect.

This information has been sourced, reviewed and adapted from materials provided by Mettler Toledo - Thermal Analysis.

For more information on this source, please visit Mettler Toledo - Thermal Analysis.