How can you freeze a mouse? - briefly
Anesthetize the specimen, then submerge it in a pre‑cooled, temperature‑controlled chamber (e.g., a -80 °C freezer) while monitoring for uniform cooling; follow institutional animal‑care protocols throughout. Proper cryogenic equipment and validated procedures are essential to ensure humane and reproducible results.
How can you freeze a mouse? - in detail
Freezing a laboratory mouse requires strict adherence to ethical standards, proper preparation, and controlled temperature management. The procedure consists of three phases: humane euthanasia, rapid cooling, and long‑term storage.
The euthanasia stage must use an approved method, such as carbon dioxide exposure or overdose of a barbiturate, to ensure rapid loss of consciousness and minimize suffering. Verification of death is confirmed by the absence of heartbeat and respiration.
Rapid cooling follows immediately after death. Steps:
- Place the mouse in a sealed, labeled plastic bag to prevent contamination.
- Submerge the bag in a pre‑cooled isopropanol bath at –80 °C for 10–15 minutes to achieve uniform temperature decline.
- Transfer the sealed bag to a mechanical freezer set to –80 °C or to a liquid nitrogen dewar for cryogenic preservation.
For long‑term storage, maintain the specimen at a constant –80 °C or in liquid nitrogen vapor phase (approximately –150 °C). Record the specimen identifier, date, and storage conditions in a laboratory inventory system. Periodic temperature checks ensure that the storage environment remains within acceptable limits.
All personnel must wear appropriate protective equipment, follow institutional biosafety protocols, and document each step according to the relevant animal welfare regulations.