As well as our article on Rubber Stoppers having a big influence on the performance during freeze drying, selecting the right Glass Vial can also improve the efficiency of your freeze-drying cycle and the lyophilization cake.
What can be advisable is to check with a supplier of packaging that this is indeed an item that should be suitable for a freeze-dry application. If an injectable it needs to be Type I glass for example also very important is the method of manufacture, the future availability, etc since all have an influence on whether it will be suitable.
Freeze Dryer – Best Practice for vials
When freeze drying, ideally you want as flat and as thin a base to the vial as possible, to ensure optimal and consistent thermal transfer from the freeze dryer shelf. These are all attributes of tubular glass vials, which are available in many sizes.
Moulded glass vials can often have ribs around the edge of the base as well as a more concave bottom which means the base of the vial isn’t as close to the freeze dry shelf and so the product in the centre of the vial cools slower than the outsides. Additionally, the base of moulded vials can be very thick, and inconsistent in shape, meaning a variation as to how much liquid is near the freeze dry shelf and less than preferable heat-transfer. If the heat transfer takes longer, this can make the freeze dry cycle longer = more time / cost.
Choose the right vial glass
If you are working on a product for injection, or for a diagnostic application, then it often makes sense to do your development in a container that is both suitable for the product, and also could be used for commercial scale-up.
We have seen people do their development in a container that is not suitable for a pharma-application, spend a lot of time and money trying to get the product stable and compatible with the material, and then a few years later they have come to commercialize the product only to find that they need to transfer to a glass or alternative polymer vial to meet the relevant Pharmacopeia, and have to repeat many of the stability and validation runs to prove that the product is OK with a different container / closure. This takes time and money, and could mean a competitor could beat you to market.
Size does matter
Very small vials do exist (for the chromatography market for example), but just because you can buy them does not mean it is a good idea to use them for your lyophilization cycle.
In some cases, very small Type I glass can have the surface quality tested on the finished vial (hydrolytic resistance testing) and you might find that the glass no longer conforms to the Type I classification.
Best in quality vial glass - Valor® Glass
Corning Valor® Glass is a revolutionary primary pharmaceutical glass package.
Valor® pharmaceutical packaging meets USP Type I hydrolytic criteria with pristine, chemically durable drug contacting surface. The composition and uniform interior surface of Valor Glass containers eliminate delamination and have low extractable concentrations – making them ideally suited to protect drug products. Potentially harmful elements such as arsenic are not added to the Valor Glass composition.
Resist Damage and Breakage
Valor Glass packaging is the ultimate solution for all pharmaceutical filling environments. It is inherently strong and damage resistant, making it better able to withstand extreme events during pharmaceutical processing such as freeze drying cycle.
Reduce Glass Particulate Generation
Valor Glass vials are extremely damage resistant and significantly reduce particle generation Valor Glass containers have demonstrated up to a 96% reduction in peak particle counts on commercial filling lines, substantially reducing risk of particle contamination.
In addition to eliminating delamination and reducing the probability of cracks, breaks and the risk of contamination, the Valor® pharmaceutical packaging technology enables smoother filling operations.
Use of Valor Glass vials reduces line interventions, enabling lines to run at much higher speeds with improved yields. Improve yield has a tremendous impact on the total cost of ownership for a freeze drying line: being, as we all know, the equipment and the time very energy consuming.