Inside a liquid nitrogen (LN₂) tank, the canisters—or lifting buckets—are the direct carriers of biological samples. While the tank provides insulation and long-term cryogenic conditions, the material of the canisters plays a crucial role in maintaining the integrity and safety of stored specimens.

Most LN₂ canisters are made from aluminum or stainless steel, chosen for their strength, durability, and resistance to low temperatures. Aluminum canisters are lightweight, easy to handle, and offer good thermal conductivity, ensuring rapid cooling of samples. However, they may be more susceptible to surface wear or corrosion if exposed to moisture or chemicals.

Stainless steel canisters, on the other hand, provide superior corrosion resistance and long-term durability. They are often preferred in medical and laboratory environments where repeated handling, sterilization, and strict hygiene are required. Their slightly higher weight makes them less convenient for frequent operations but enhances their robustness under demanding conditions.

The design and coating of canisters also influence sample safety. Smooth surfaces and protective finishes help reduce the risk of contamination, while well-engineered perforations ensure efficient nitrogen circulation for uniform cooling. Conversely, poorly made or low-quality canisters can lead to uneven temperatures, physical damage to vials, or even compromised sterility.

In addition, material choice affects trace element release. High-quality canisters minimize the risk of chemical leaching into samples, which is especially important for sensitive applications such as IVF, genetics, or biopharmaceutical storage.

In conclusion, the material of LN₂ tank canisters is more than a structural detail—it is a safeguard for sample reliability. Choosing durable, corrosion-resistant materials and ensuring high manufacturing standards is essential for protecting valuable biological resources during cryogenic storage.