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Two breakthrough technologies offer freeze drying scientists tools to streamline cycle development and gain even greater control over the freeze drying process.
SMART Freeze Drying Technology™
SMART Freeze Drying Technology™ from SP Scientific enables the process of developing lyophilisation cycles to be streamlined.
Typical cycle development involves calculating a trial cycle from critical temperature data and then evaluating and refining the cycle over a series of runs based on detailed analysis of the process data. SMART uses inputted batch information to calculate a test cycle, which it then automatically refines using detailed process monitoring.
In addition to the its use in optimising freeze drying cycles, this system can also calculate and report a number of critical process and product parameters, including product resistance (Rp), sublimation rate (dm/dt) and dry layer thickness (Ldry) during primary drying.
SMART can return a safe, optimised cycle in as little as one or two runs, ready for scaling up to production.
Testing a series of experimental runs can consume large amounts of expensive active material.
Because SMART condenses this process to just one or two runs, material costs can also be greatly reduced.
Controlled Ice Nucleation
When conducting process development the focus is often the drying stages, however the freezing stage is also important. The structure of the ice crystals determines the structure of the dry or drying product and will consequently affect the rate of drying.
Across a freeze dryer chamber or shelf it is common for ice to nucleate at different times and at different rates. This can cause variances in the rate of drying between batches or even in the same batch, which can ultimately cause differences in the product quality.
ControLyo reliably controls ice nucleation in freeze drying. Not only can the product be frozen across the chamber at the same time, the size of the ice crystals can be controlled. The lower the nucleation temperature, the more super-cooling takes place. A high degree of super-cooling leads to small ice crystals, which in turn results in product morphology of small pores during and after sublimation.
These small pores create a high resistance (Rp) to mass flow (water vapour leaving product via sublimation). Because of the high resistance, primary drying is relatively slow. When nucleation is forced at higher temperatures with controlled-nucleation technology, larger ice crystals are formed, which result in larger pore structure. This morphology of larger pores allows for lower resistance to mass flow and faster primary drying rate.
Manometric temperature measurement (MTM) is another process analytical technology (PAT) available on certain freeze dryers. MTM can be used in conjunction with specialised monitoring software to provide an automated tool for identification and control of important process parameters during the primary drying phase of freeze drying.
The SP Scientific Lyostar has the capability to combine both automated SMART and ControLyo technologies. This provides a unique opportunity to implement controlled nucleation as part of cycle optimization as calculated and performed by the SMART software. The product related properties can be instantly linked to important process performance attributes.
To find out more about SMART Freeze Drying Technology™ or training on freeze drying process development , please contact us on firstname.lastname@example.org or +44 (0)1962 841092Tags: cycle development, freeze drying, freeze drying analysis, lyostar, process development