Historically, the need for biological storage was less extensive than is the case today and the measures employed consisted mainly of sealing specimens into sterile tubes or bottles and keeping them in a commercial refrigerator.  While this may have sufficed for blood and other body fluid samples awaiting culture or microscopic examination, the degree of preservation offered was, in most cases fairly limited and designed to meet the needs of any potential pathogens present in the specimen rather than those of the potentially infected material itself.

Today, the increasing need to preserve various forms of living tissue obtained from human subjects has necessitated the development of far more sophisticated technology of which cryopreservation tends to be that which is most commonly applied. For preserving living materials such as bone marrow for transplantation or ova and sperm used for in-vitro fertilisation, exceptional biological storage facilities are vital.

The limited cooling offered even by the most efficient commercial refrigerators is simply insufficient to prevent eventual damage to viable materials for more than relatively short periods. Cellular integrity in such samples can only be maintained under super-cooled conditions and to achieve this, a technology known as cryogenics was developed in which liquid nitrogen is used to generate ultra-low temperatures while avoiding the formation of ice crystals that might otherwise cause damage to delicate tissues during the process.

Once frozen in this manner, the stored samples must be continuously monitored so as to ensure that, for the duration of freezing, their temperature remains within the range that is deemed to be optimal for safe biological storage of the samples concerned. Thawing of the samples must also be undertaken with due precautions, if one is to minimise any risk of damage.

Cryopreservation then, is obviously a procedure that can only be undertaken with the specialised equipment designed for this purpose. Currently Chart and Planer, along with Cryo Bio System, are regarded as the world leader in this field and, in South Africa, their products are all available from and expertly supported by a single local specialist – IEPSA.

With close to 35 years in the business, we have expanded considerably since our early days of sourcing and supplying medical diagnostic reagents and equipment. Today, we also serve the needs of transplant surgeons, stem cell researchers, veterinarians, oncologists, assisted reproduction specialists, and anyone who may have a need for an efficient biological storage system.

Our policy is a simple but important one. We source only the very best quality items from the established industry leaders in this and the other fields that we serve which now include various other medical disciplines, the pharmaceutical industry and the manufacturers of processed foods and beverages.

In our Chart MVE Biological Systems range we offer the Lab Series with its super-insulated Dewars, seen as the most convenient and inexpensive means for storing and dispensing liquid nitrogen. In addition, the Doble Series features unique tanks deigned not just for liquid storage but are also suitable for vapour shipment while, the ETERNE liquid nitrogen vapour storage freezers provide the ultimate in sample security.

Best of all, whatever the circumstances, expert IEPSA technical support is always on hand to assist with the operation of your equipment whether for food analysis, diagnostic testing or biological storage.

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