What is the primary active agent in unsaturated chemical vapor sterilization?

In unsaturated chemical vapor sterilization, the primary active agent is formaldehyde. This method involves the use of a mixture of chemical vapors, and formaldehyde serves as the key component due to its effectiveness in destroying bacteria, viruses, and fungi through the process of cross-linking proteins and nucleic acids.

The unsaturated chemical vapor sterilization process operates at lower temperatures compared to steam sterilization, making it suitable for heat-sensitive instruments. The formaldehyde vapor penetrates materials effectively, allowing for thorough sterilization without the moisture that is present in steam methods.

This method's efficiency is why it has been a standard practice in settings requiring sterilization of dental and medical instruments, especially those which cannot withstand high heat or moisture.

Other agents mentioned do not serve this same primary role within the context of unsaturated chemical vapor sterilization. For example, hydrogen peroxide is used in other sterilization processes, but not as the primary active agent in this vapor method.