The operation of freezing and a product’s thermal history has influences in the moment to moment process in freeze drying. Depending upon the mode of freezing, the performance of the lyophilizer has to match conditions which generate the appropriate conditions required by product formulation and a particular freezing history.
As little as a 15 minute inappropriate shelf temperature excursion, or pressure excursion in an inappropriate way, may cause the product to lose efficacy, solubility and other traits or perhaps change the product in ways not considered by release criteria. A thorough understanding of heterogeneous and homogeneous nucleation, the synergistic effect that various solvents, impurities, cryo-protective additives, reconstitution additives, buffers, and position of the product inside the chamber during freezing, all work to produce these profound influences. It is the engineers task to carefully analyze and design the process envelope needed to produce a robust cycle, and consistent end product; batch after batch. Once nailed down, the process of freezing and freeze drying within the process envelope, can be repeated with powerful, positive, and acceptable results.
Applewood Scientific supplies assistance and analysis of your team’s chosen freezing regime, in association with known eutectic product behavior. We can work with your team to ensure the desired freezing effect or help your team develop the skills, find the appropriate equipment, suggest engineering changes to enhance freezing or locate service providers so that your team has the resources.