What is freeze/thaw stability?

Freeze-thaw cycle testing is a part of stability testing that allows you to determine if your formula will remain stable under various conditions. This type of test puts your sample through a series of extreme, rapid temperature changes that it may encounter during normal shipping and handling processes.

How many freeze-thaw cycles for serum?

In the case of serum, it has been reported that VEGF levels are not affected by repeated freezing and thawing 13, 24; however, our study shows that VEGF levels were slightly elevated after five freeze–thaw cycles.

What is freeze/thaw degradation?

Freeze-thaw damage is a potentially serious deterioration process that occurs in concrete structures in cold climates. Premature damage to concrete slabs during freezing and thawing cycles represents a major challenge to pavement durability and resilience.

What is cyclic freezing?

Cyclical freeze–thaw causes the redistribution water and salt in soil. Temperature gradient is one of the external agents of the soil water movement. The salt migration is influenced by factors influencing water movement in addition to various physical and physicochemical matters.

How do you improve freeze/thaw stability?

A few tips on how to make your products freeze-thaw stable.

  1. Use materials that has the ability to bind water.
  2. Use efficient stabilizers that can keep the formulation ingredients in a dispersed and homogeneous position throughout the formulation and reduce structural changes that can occur after thawing.

How do you prevent freeze-thaw?

Some common methods for preventing freeze-thaw are:

  1. Using Deicing Chemicals. One of the simplest ways to prevent concrete freeze-thaw damage is with deicing chemicals.
  2. Reviewing Concrete Structure and Environment. High-quality concrete can also help to prevent deterioration.
  3. Applying a Sealer.

What are freeze/thaw cycles?

A freeze-thaw cycle is the freezing and thawing of water inside pipes associated with the winter months. The temperature even in winter is never uniform, and fluctuates frequently. This causes the water inside pipes to freeze in very frigid temperatures and thaw when temperatures rise a little.

Why repeated freeze/thaw of samples are not ideal?

For example, multiple rounds of freezing and thawing can damage protein structures, which can interfere with study protein kinetics using surface plasmon resonance. Even minor DNA damage can result in uninterpretable data from PCR. Your samples are not the only concern when it comes to freeze-thaw cycles.

What is freeze and thaw cycle?

What does freeze/thaw do to proteins?

During thawing, additional damage to proteins is caused by recrystallization process. Recrystallization exerts additional interfacial tension or shear on the entrapped proteins and hence causes additional damage to the latter.

How do you thaw frozen antibodies?

If the antibody arrives frozen, thaw it and place it on ice. If it is in liquid, immediately place it on ice. b. Gently vortex the antibody solution and spin briefly (at 5,000-10,000 x g for 10 seconds to pull down solution) in microcentrifuge to collect all liquid at bottom of tube.

How can the resistance against freeze and thaw be increased?

The resistance of concrete to freezing and thawing in a moist condition is significantly improved by the use of intentionally entrained air.

Can you freeze insulin?

The BD Diabetes site says that “once insulin is frozen, it loses its potency.” And the Wisconsin Department of Health agrees. But wait a sec. Endogenous human insulin can be frozen. In fact, blood samples for insulin level tests are supposed to be frozen.

Does insulin have a lower freezing point than alcohol?

So from all this comparative science, we cansafely infer that the freezing point of insulin is much closer to that of water than it is to wine (typically 13.5% alcohol) or to whiskey (typically 40% alcohol). Therefore the answer to your question is: Insulin is more like water than anti-freeze.

What is the concentration of glucose in thawing?

However in a study ( 11 ), glucose concentrations were found as increased from 11.8 to 14.0% in human serum refrozen and thawn even once. Protein stability is problematic.

How long are common clinical chemistry analytes stable after freezing?

As a result, common clinical chemistry analytes, with considering the variability of unstable analytes, showed adequote stability after 3 months of storage in sera at −20 °C, or up to ten times of freeze-thaw cycle. All the same, such analysis can only be performed for exceptional cases, and this should be taken into account while planning studies.