1. Firstly, improves freeze-thawing quality of biologic drug substances
2. Secondly, can be manufactured for different bottle sizes and shapes
3. Thirdly, it is easy to remove and reuse
Isothermal shield
The Isothermal Shield is the unique insulator that prevents both protein aggregation and container damage caused by pressure.
Designed for bottles and carboys, it is an insulating cover to prevent the development of an ice crust during freezing. Consequently, the ice crust can make it difficult for water to expand during freezing, thereby increasing pressure and mechanical stresses to proteins and containers. This can lead to protein aggregation and container failure.
Reducing interfacial and mechanical stresses in bottles.
At the top, the liquid rapidly freezes and forms an ice-crust that encloses the remaining liquid phase when the Isothermal Shield is not used. Meanwhile, this increases the pressure of the confined liquid.
As a result, the ice-crust entraps the liquid phase and pushes it, creating a mound-like structure at the top of the bottle on the right-hand side of the image. Additionally, air bubbles typically get entrapped within the ice-crust, forming a foamy-like ice structure that presents a higher interfacial tension.
The image demonstrates the performance of an Isothermal Shield at -80 °C, using a 0.5 L bottle with a 10% (w/w) sucrose solution. In contrast, the left-hand side of the image shows the result with the Isothermal Shield, highlighting a flat interface, while the right-hand side displays the result without shield, resulting in an ice-mound on the top.
improves protein stability
Comparison between bottles with and without Isothermal Shield.
From left to right-hand side, the images show:
- Magnetic Ressonance Imaging (MRI) of the ice matrix;
- Local concentration of protein (defined as C/C0), measured after sampling from the frozen solution;
- Local variation of Δ% of aggregates (relative to initial solution before freezing).