Freeze drying (or lyophilization) of bacteria interrupts the metabolism of a bacterial culture putting into a dry powder resting state. Bacteria are revived from the dry powder by the addition of water and nutrient media. After lyophilization, bacteria in the dry state may be stored for a long period.
Difficulties in the freeze drying process lie in removing water while retaining the ability of the bacteria to be revived when rehydrated. Various sugars, proteins, small molecules and salts are used to formulate and protect the bacteria during the drying process and subsequent rehydration. Equally important are the methods used for freezing and evaporating the water. A well designed formulation and lyophilization cycle can produce a bacterial product that can be stored and revived on cue.
Bacterial stocks have been formulated and lyophilized as part of our standard operating procedures at List Labs for more than thirty years. Let us put our experience to work in formulating and drying your cell bank or live biotherapeutic.