Due to their size, special accommodations must be taken when connecting them to the collector and it is difficult to lyophilize large numbers of samples at the same time.Īn Ampule Valve Adapter allows a single ampule to be connected directly to a single valve. Traditionally, ampules are used for long-term storage making it critical they are sealed under vacuum. This creates an insulation of ice all the way around your sample that will lyophilize with your sample.Īmpules are glass tubes that are made for very small samples that will be heat sealed under vacuum. For samples in a tube, simply place the tube in a flask, fill the flask with water and freeze the entire flask. A flask can be wrapped with any sort of insulating material, such as packing foam, to create a barrier between the sample and room atmosphere. This creates an even air gap around the sample flask and slows the heat transfer from the room air to the sample.Īlternate options to avoid sample melt back are to insulate the sample container with other materials. Labconco offers Flask Holders that insulate a sample by holding a sample flask inside a larger flask. This is difficult when freeze drying in a flask, as the heat input is essentially the room temperature that cannot be easily regulated. The best way to prevent sample melt back is to limit the heat transferring into the sample. Unfortunately, sample melt back occurs frequently with several common sample types. Paired with an isolation valve and a clean bench, the Mini Stoppering Chamber can make stoppering under vacuum in a sterile environment easy. It accommodates small bottles and has a capacity of up to forty-eight 2 milliliter bottles or eight 30 milliliter serum bottles. It has an area of approximately 18 square inches and is ideal for very small sample sizes or just a few samples that need to be stoppered. This small chamber connects directly to the valve of a drying chamber or manifold like a flask. The smallest and most economical accessory for stoppering under vacuum is the Mini Stoppering Chamber. It holds fewer samples than the FreeZone Stoppering Tray Dryer and uses a more manual process, but the Clear Stoppering Chamber makes sense if your stoppering needs are infrequent or on a smaller scale. The Clear Stoppering Chamber has a handle that, when turned, applies pressure to the shelves, collapsing them onto one another and pushing the stoppers into the vials. Essentially, it is a clear chamber with two heated shelves (+40° C) that provide 158 square inches of area. The second option, less expensive than the first, is a stoppering chamber or shelf, which connects to the collector like a drying chamber. The FreeZone® Stoppering Tray Dryer has three temperature-controlled shelves (-40° C to +40° C) with 588 square inches of area on which to place samples, which can hold up to four hundred 2 ml serum bottles. Although they require a substantial investment, stoppering tray dryers can handle large quantities of samples and offer sophisticated programming capabilities. The first option is a stoppering tray dryer. There are three choices, and deciding which to use depends on the size and number of samples you have. Stoppering under vacuum is determined by your quantity and budget. Placing airtight seals on the vials before they are exposed to the atmosphere where they can absorb moisture keeps the samples drier. When samples are stoppered under vacuum, their shelf life is increased dramatically. Using accessories designed for specific samples and challenging applications helps make lyophilizing these samples easier. Freeze drying, or lyophilization, is a time consuming process that can be easy or difficult depending on the sample type, sample size and requirements.
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