What substance should cryostats used on a suspected CJD case be decontaminated with?

Cryostats, which are used to cut tissue samples for microscopic examination, must be properly decontaminated in cases where there is a suspicion of transmissible spongiform encephalopathies like Creutzfeldt-Jakob disease (CJD). The correct decontaminating agent is sodium hydroxide.

Sodium hydroxide is effective because it is a strong alkaline agent that can denature prion proteins, which are responsible for CJD. Prions are notoriously resistant to conventional disinfection methods, including alcohol and water, and they do not break down easily. Therefore, using sodium hydroxide is recommended to ensure that any potential infectious material is rendered non-viable.

In contrast, alcohol, water, and citric acid do not have the same potency against prions. Alcohol may effectively decontaminate other pathogens but is insufficient for prion inactivation. Water, while serving as a solvent, lacks the chemical properties needed to degrade prion structures. Citric acid, primarily utilized for its antimicrobial properties against bacteria and some viruses, similarly does not have the efficacy required against prions. Hence, sodium hydroxide stands out as the appropriate choice for decontamination in this specific context.