Microbial Freeze Drying Buffer (Filter Sterilized) is a proprietary solution of hydrolyzed plant protein (a substitute for bovine serum albumin) and carbohydrate lyoprotectant meant for the long-term preservation of microorganisms, including both bacteria and fungi. This formulation evolved from Reagent 18, a proven solution for microbial freeze drying described in the ATCC lyophilization manual. Superior to traditional additives like sucrose and skim milk, Microbial Freeze Drying Buffer has a 90% viability of bacteria and is free of all animal products and proteins. This buffer maintains microorganisms’ viability through freezing, water removal, and subsequent storage of freeze dried microbial samples. While sucrose often collapses and shows slow dissolution, OPS Diagnostics’ buffer is less likely to collapse and the dissolution of freeze dried cells is quite rapid.
To use this reagent, cultured microorganisms (e.g. log-phase bacteria) are pelleted by centrifugation, the culture broth is decanted, and the pellet is resuspended in Microbial Freeze Drying Buffer. Next, freeze drying can be done using a protocol that is supplied with the buffer for one of two methods, either for simple culture preservation or for the preservation of a large number of cells. Lyophilization can be performed with both shelf and manifold type systems.
This freeze drying buffer is sterile filtered and aseptically packaged in 500 ml PET bottles. The shelf life is two years at room temperature with no loss of functionality if aseptic techniques are employed. Ready-to-use Microbial Freeze Drying Buffer from OPS Diagnostics is more cost effective than formulations containing BSA.
For more information on microbial freeze drying and preserving microorganisms, please visit the following pages:
Bacteria Freeze Drying Protocol
Bacteria Lyophilization Overview
Survival of Escherichia coli in Four Lyophilization Solutions
Lyophilization Reagents Shelf Life Study
A Guide to Bacterial Preservation: Refrigeration, Freezing and Freeze Drying