What is the purpose of Cryoguard™ indicators?

Cryoguard Thermal Exposure Indicators signal thermal exposure or temperature abuse in cryopreserved materials. The indicators are used to:

• Monitor frozen materials during shipping or storage.
• Signal temperature damage during removal and replacement of samples from freezers.
• Detect failures or fluctuations in refrigeration or freezers.

How do Cryoguard indicators work?

When an indicator is exposed to temperatures above its signal temperature, it irreversibly changes color from green to red (see signal temperature graph below). This irreversible color change signals temperature abuse of cryopreserved materials that might otherwise go undetected.

Signal Temperature Graph:

What type of materials do Cryoguard indicators monitor?

Customers use Cryoguard Thermal Exposure Indicators to monitor:

• Stem cells. Cord blood, bone marrow stem cells, peripheral blood stem cells & more
• Reproductive Samples. Sperm, embryos, vitrified oocytes “eggs,” testicular tissue & more
• Adhesives. Premixed epoxy resins  and polysulfide sealants for aerospace applications & more
• Vaccines
• Pharmaceuticals
• Bone grafts
• Tissue Samples
• Organs
• Blood Products
• Chemicals
• Refrigerated or Frozen Products
• Other Cryopreserved Materials

What signal temperatures are available?

Cryoguard Thermal Exposure Indicators are available with four (4) different pre-set "signal" temperatures, which correspond to a variety of scientific, medical and commercial applications:

• -40º C (M40 Buy Now!)
• -70º C (M70 Buy Now!)
• -100º C (M100 Buy Now!)
• -120º C (M120 Buy Now!)

Indicators should be chosen with signal temperatures at least 30ºC higher than that of the environment to be monitored. Thus, the M-40, M-70, M-100 and M-120 indicators are recommended for monitoring environments at or below -70ºC, -100ºC, -130ºC and -150ºC, respectively.

What exactly are Cryoguard indicators?

Each Cryoguard Thermal Exposure Indicator is a chemical formulation sealed in a cylindrical polycarbonate vial. The vials are about ½” in diameter and about 1” long.

How are Cryoguard indicators activated?

Indicators are activated by freezing them to at least 30°C below their signal temperature, and then depressing an activator pin in the bottom of the unit. (see Cryoguard indicator activation diagram.) For more information on activation, see the activation tips page.

What is the shelf life for Cryoguard indicators?

Cryoguard indicators have a shelf life of eight months. The shelf life applies whether the indicator is activated or unactivated. An expiration date appears on the label on each indicator.

With what type of shipping/storage containers are Cryoguard indicators compatible?

• liquid nitrogen dewars
• liquid nitrogen “dry shippers”
• liquid nitrogen (LN2) tanks
• MVE Biological Systems Products
• Foam coolers
• Insulated boxes
• Containers cooled by dry ice

How do Cryoguard indicators attach to cryogenic materials?

Cryoguard indicators can attach to frozen products in a number of convenient ways. See pictures.

• Fits in ½” partitions of freezer boxes
• Fits inside the lid of most cryovials
• For a better fit inside a cryobox, remove the lid from an empty cryovial, place a Cryoguard indicator into the top of the vial, and place the cryovial holding the Cryoguard indicator into one of the slots in the dividers within the cryobox. Optionally, add an alert label sticker (included with your purchase of Cryoguard indicators) on the outside of the cryobox. This warns the individuals handling the samples of the danger of thermal exposure and promotes quality assurance during removal and replacement of samples from freezers.
• Snaps onto cryovial freezer canes
• Can be wired to perishables

Why choose Cryoguard indicators?

Cryoguard Thermal Exposure Indicators are:

• Unique. No other temperature sensor provides an at-a-glance warning for thermal exposure at such low temperatures. Cryoguard indicators signal thermal exposure at subzero temperatures as low as -120˚C/-184˚F.

• Cost effective. Prices as low as $10.38 per indicator.

• Simple. See Cryoguard indicator results on the spot. Indicators irreversibly change from green to red when they encounter excessive exposure to temperatures above the signal range. No need to download temperature data onto a computer.

• Hassle Free. Cryoguard indicators are disposable. Save time and money wasted on recovering and returning thermal recorders.

• Versatile. So small, Cryoguard indicators fit in partitioned freezer boxes, attach to most cryovials or snap onto standard cryovial freezer canes.

Pairing Cryoguard indicators with a temperature data logger provides a real-time readout of thermal exposure prior to processing data from the temperature data logger.