The Critical Formulation Temperature In Freeze-Drying

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•Presentation: The Critical Formulation Temperature In Freeze-Drying

In order to develop an optimized freeze-drying process, we must access the "critical temperature" of a formulation, using a technology that provides accurate and representative measurements.

In R&D, the glass transition temperature of the maximally freeze-concentrated solute (T_g') is often used as the critical temparature, although T_g' and the collapse temperature (T_c) are frequently reported to show a bias for 1 - 5⁰ C for the same formulation.

Important: a 1⁰C increase in product temperature may result in as much as a 13% increase in a primary drying rate and therefore, shorter drying time.

For a solute system which remains amorphous during freezing and drying, T_c is the maximally tolerable product temperature during primary drying which ensures an elegant cake.

Primary drying T_c may result in:

• an unacceptable appearance of the product
• prolonged reconstitution times and/or an imcomplete reconstitution
• elevated residual moisture levels in the product and
• instability during storage due to elevated mobility within the matrix (proteins,peptides etc.,)

Click Here To Download:
•Presentation: The Critical Formulation Temperature In Freeze-Drying