1. The importance of cryogenic storage in the laboratory

What Items Need to Be Stored at Low Temperature?

  1. Most medical reagents, biologics, enzymes, vaccines and medicines.
  2. Specimens of bacteria, viruses or other animals and plants that need to be conserved or studied by hospitals and research institutes, as well as some special cells, skin, organs or other living specimens.
  3. Good breed gene or semen retained by livestock husbandry systems and aquaculture agriculture.
  4. Chemical industry for certain electronic components or precision instruments need low temperature treatment.
  5. Ordinary laboratory standard solution, reference substance, etc., microbial strains of bacteria and culture medium.

Cryogenic Preservation of Significance?

  1. In the low temperature conditions, to avoid certain drugs, biological agents, enzyme vaccines deteriorated by the influence of the external environment. Low temperature can slow down the denaturation or degradation of effective ingredients.
  2. For the living body, under low temperature conditions can slow cell division and metabolic activity, in a long period of time to maintain a good original state, greatly improving the survival rate.
  1. 2 Laboratory Cryogenic Storage Equipment

Cryogenic storage device classification
(A) Drugs cool cabinet / drug freezers
(B) blood freezer
(C) low temperature refrigerator / ultra-low temperature refrigerator
(D) liquid nitrogen tank

  1. Drug cool cabinet /Drug Freezers

A number of factors are crucial to ensure the quality of medicines, samples and reagents, namely storage temperature, expiration date, UV exposure and humidity.

The most important of these is the storage temperature. Usually we see the drug storage temperature, there are room temperature, shading cool, there are requirements for refrigeration, these conditions require the specific temperature is:

  1. Room temperature: 10 ℃ ~ 30 ℃
  2. Cool preservation temperature: not more than 20 ℃
  3. Refrigeration temperature: 2 ℃ ~ 10 ℃
  4. Not specified temperature requirements, generally refers to room temperature.
  5. Relative humidity should be maintained between 35% and 75%.

Drug cool cabinet (8℃~20℃)
It is a necessary storage equipment for all the drugstores. It is suitable for storing drugs, reagents and samples at 8 c ~20 C.
Main storage of drugs in the drugs cool cabinet are:
(1) cardiovascular and cerebrovascular drugs;
(2) antibiotics;
(3) eye drops and other liquid drugs;
(4) suppository creams that may soften above 20 ° C;
(5) children’s medication;
(6) vitamins and other nutritional drugs.

Drug Refrigerator (2 ℃ ~ 8 ℃)
It is a special refrigerating equipment for refrigerated medicine in the medical industry. It can also be used for refrigerating biological products, reagents, vaccines and so on. Apply to hospitals, pharmacies, clinics, CDC, universities, blood stations, inspection and quarantine agencies and pharmaceutical companies and so on.

Drug freezers are mainly used for: refrigerated vaccines, blood products, monoclonal antibodies, insulin, interferons, some antibiotics, other protein preparations.

The difference between a drug refrigerator and a household refrigerator

category Household refrigerator Drug freezers Medicines refrigerators advantage
temperature range 0-10 ° C 2-8 ° C Avoid freezing below 0 ℃ to prevent items from freezing
temperature control Mechanical temperature control Digital temperature control Accurate temperature control, not affected by ambient temperature, to avoid the risk of damage to the item
Cooling method Direct cooling Air-cooled Circulation fan and duct design, to ensure air-conditioning cycle, to avoid freezing caused items damaged
Alarm prompt No alarm There are alarms Multiple fault alarm, flashing light alarm, remote alarm can be accessed
Key components Strict cost control High-cost international brands Avoid the impact of low-cost components on professional performance
Storage purposes Storage food and beverage Store the reagent vaccine blood Professional storage equipment, high standards, storage rest assured
Storage time Storage time is not demanding Storage time is not demanding There is plenty of storage time to choose from, without worrying about the risk of short-term storage
  1. Blood bank refrigerator (4±1℃)

The blood refrigerator is a specialized refrigerated equipment for the medical industry to refrigerate blood (whole blood). It is suitable for the storage of blood in hospitals, blood stations and medical research departments.

  1. Low temperature freezers / ULT freezers

Low-temperature freezers, refers to the freezer which take use of mechanical refrigeration to get a certain temperature .According to the temperature can be divided into low-temperature freezers and ultra-low temperature freezers.
-25 ℃ low temperature freezer
-40 ℃ low temperature freezer
-60 ℃ low temperature freezer
-86 ℃ low temperature freezer
-105 ℃ low temperature freezer
-136 ℃ low temperature freezer
-152 ℃ low temperature freezer

Application of low temperature refrigerator
Mainly used in blood stations, hospitals, health and epidemic prevention systems, research institutes, electronics industry, chemical industry, biological engineering, university laboratories, military enterprises, offshore fishing companies.

  1. Food freezing: temperature range -18 ℃ ~ -28 ℃, for meat, fish, seafood and other refrigeration, storage period of 1-3 months; cold food and beverage industry
  2. Scientific research: temperature range -30 ℃ ~ -85 ℃, for the test of instrumentation products and electronic components in the low temperature environment performance changes ;
  3. Biomedical Engineering: Temperature range -30 ℃ ~ -85 ℃ (or lower), for the preservation of organs, skin, bacteria, viruses, sperm, blood, and other biological products.

4 Liquid nitrogen tank（-196℃）
As for the content of the liquid nitrogen tank, we have arranged very comprehensive content before:
The knowledge of liquid nitrogen tanks must be understood by the sales staff of the instrument
Application:
1, Livestock industry: livestock semen, frozen storage of embryos;
2, Medical profession: human stem cells, plasma, internal organs, biological samples, such as frozen storage and treatment of skin diseases;
3, Scientific research units: vaccines, viruses and other microorganisms incubator and storage equipment;
4, Industrial areas: industrial molds, knives, cutting tool cryogenic treatment, mechanical cold assembly.
5, Food: food frozen, liquid nitrogen ice cream, molecular cuisine, beverage processing  and so on.

Liquid Nitrogen Tank Category:
1, portable liquid nitrogen tank
Mainly used in the breeding of poultry husbandry and biological samples of portable transport;
2, stored liquid nitrogen tank
Mainly used for long-term static preservation of biological samples;
3, transport-type liquid nitrogen tank
For long-distance transport of liquid nitrogen or biological samples;
4, large-caliber laboratory liquid nitrogen tank
Mainly used for long-term preservation of biological samples but need frequent sample extraction;
5, air transport liquid nitrogen tank
Dedicated to transporting biological samples by aircraft such as aircraft.

The advantages and disadvantages of cryogenic refrigerator and liquid nitrogen tank to storage samples

Both cryogenic refrigerators and liquid nitrogen tanks can be used to freeze biological samples such as stem cells, plasma, semen, cells and strains. The difference is that:

1, Liquid nitrogen temperature is lower, can reach -196 ℃, life activities within the sample basically stopped at this temperature, the stability of the sample can be long-term preservation.
2, Ultra-low temperature refrigerator is electric cooling, cooling rate of electric cooling is lower than liquid nitrogen, once opened the container to pick up the sample easily lead to a wide range of temperature fluctuations, the temperature recovery time is relatively long, and therefore more suitable for less open to take sample situation. In addition, electric refrigerator must protect the power supply. Liquid nitrogen equipment is recommended to provide backup storage in the event of a power outage.
3, Liquid nitrogen container liquid sample storage needs further protection for cross-contamination between samples. Frozen tube lax seal, easily lead to liquid nitrogen penetration into the frozen tube to increase the risk of cross-contamination between samples. One solution to this problem is to use a special cryogenic tube to shrink the cryopreservation tube, or use a sealant membrane to wrap the tube around the cryopreservation tube cap for 2-3 turns.

  1. The type of Cryogenic storage sample in laboratory

Blood
（1） Blood preservation
1, Whole blood, red blood cells: (blood freezer)
Storage temperature: 2 ℃ ~ 6 ℃.
2, Frozen red blood cells:
Storage temperature: Frozen red blood cells containing 20% glycerol stored at below -120 ℃, frozen red blood cells containing 40% glycerol stored at below-65 ℃.
3, Platelets, granulocytes (platelet shaking preservation box)
Storage temperature: 22 ℃ ± 2 ℃, shake culture
4, Plasma: (low temperature refrigerator, liquid nitrogen tank)
Storage temperature: below -18 ℃.
After thawing, preservation at 2 ℃ ~ 6 ℃ , infusion should be within 24h
Drug
Drugs refer to those substances that are used to prevent, treat, diagnose, cure, and purposefully regulate the physiological function of the human body and provide indications or functions and indications, usage and dosage, including Chinese herbal medicines, traditional Chinese medicines prepared in ready-to-use forms, proprietary Chinese medicines, chemical raw materials and its preparations, antibiotics, biochemicals, radiopharmaceuticals, serums, vaccines, blood products and diagnostic drugs, etc.

Maintenance of common perishable dosage forms in drugs

1) Tablets, syrups, capsules: 8 ~ 20 ℃; (drugs cool cabinet)
2) Water, ointment, suppository, water injection, injection: room temperature 10 ~ 30 ℃
3) Antibiotics, biological products, enzymes and other injection: 2 ~ 8 ℃ (drug freezers)
Vaccine
Vaccine refers to biological products for inoculation which take use of various types of pathogenic microorganisms . Vaccines which are made of bacteria or spirochetes are also called bacterins. Vaccine is divided into live vaccine and dead vaccine. Commonly used live vaccine include BCG, poliomyelitis vaccine, measles vaccine, plague vaccine and so on. Commonly used dead vaccine include pertussis vaccine, typhoid vaccine, meningococcal vaccine, cholera vaccine and so on.

Vaccine storage temperature:
Live Vaccine: below -15 ℃ (low temperature refrigerator)
Inactivated vaccine (dead vaccine): 2 ~ 8 ℃ (drug freezers)