In crystalline solutions this is the eutectic point (Teu) and in amorphous products this is the collapse temperature (Tc). Information on how the product behaves as temperature increases is vital for successful freeze drying. Product that collapses during freeze drying can suffer from a range of problems including reduced shelf life, reduced activity and poor reconstitution.
Knowledge of a product’s collapse behavior is vital when:
Optimising existing processes
Developing a formulation for freeze drying
Developing a new cycle
Freeze Drying Microscopy
Freeze drying microscopy (FDM) was established in the 1960s as a technique for identifying critical formulation parameters and is the only method for reliably determining collapse temperatures. Historically FDM was used only for collapse / eutectic temperatures but the latest generation FDM can also enables identification of crystallisation phenomena, the potential for skin/crust formation, and the effects of annealing on ice crystal growth and solute structure.
Lyostat analysis uses just 2µl and is typically complete in under an hour. Lyostat is supplied fully validated as a complete working system against a series of standard solutions. Full installation and training is offered as standard. Uniquely, as well as instructing correct use of the equipment, our training provides practical tuition on interpretation of results from scientists with in-depth knowledge of freeze drying. Installation and operation qualification (IQ/OQ) packages are also available, and can be customised to bespoke specifications if required.
Lyostat is PC controlled to provide sophisticated image and data capture and analysis functions, which also allows the user to make a video of their sample under analysis. The software is also available in a 21CFR11 compliant version.
Take a look at this short presentation that looks at the key benefits that TASC (Thermal Analysis of Surface Characterisation) software offers to those who need to interpret thermal analysis results and the key principles of how it works.
What the Technique / Instrument Is:
Thermal Analysis by Surface Characterisation (TASC) is a software addition to the Lyostat that is used to analyse data files generated by the LINK software post-analysis.
It is suited to the high resolution (2.3MP) of the PointGrey colour camera and to the fixed and reproducible focus on the Lyostat imaging station.
How It Works:
TASC analyses incremental changes to successive images in the focus area by the brightness and colour of each pixel, to produce a normalised TASC trace overlay to the data graph.
It then looks at changes in the selected area and shows a change in the line based on the degree of collapse. If the collapse temperature is roughly known (by visual inspection of the data file) TASC can then pinpoint the start of this collapse in this region.
Accurate and quantitative analysis
Reduces operator error in the analysis of the precise collapse temperature
Can retrofit to previous results to check validity
Flexible analysis useful for many other application outside of freeze drying using the Lyostat5 – online resources available for more information