Final answer:
Medium risk drugs require specific conditions for storage to maintain their stability, with short-term room temperature suitable for immediate use, and ultra-low temperatures for long-term storage preservation. Repeated freeze-thaw cycles can degrade the substances, necessitating careful management of storage conditions.
Step-by-step explanation:
Medium risk drugs and other medical specimens require specific storage conditions to ensure their post-preparative stability. For long-term storage, these items are often kept at ultra-low temperatures, sometimes using liquid nitrogen tanks to maintain temperatures below -196°C or in ultra-low freezers that go down to around -70°C. Short-term temperature stability at room temperature is generally suitable for immediate use or short-term transport, but for more extended periods and to maintain the mean concentration within ±15% of its nominal value, colder storage is necessary. The freeze-thaw cycle is also a crucial factor; repeated freezing and thawing can degrade the substance, which is why proper storage techniques are essential. Examples of storage conditions include keeping nitrate reagents at 4°C or storing bacterial cultures in ultra-low temperatures for preservation.