Which method is preferred for storing samples to prevent contamination?

The preferred method for storing samples to prevent contamination is the use of brass or stainless steel tubes. These materials are non-reactive and help preserve the integrity of the samples by providing a sterile environment that minimizes the risk of contamination from external sources.

Stainless steel in particular is known for its durability, resistance to corrosion, and ease of cleaning, making it ideal for sample storage. It does not leach chemicals into the samples, which is crucial for maintaining their purity and ensuring accurate results in further analysis. Additionally, metal tubes can be securely sealed to prevent any contaminants from entering.

In contrast, the other options present various risks for contamination. Plastic containers with wide openings can allow for easier access to pollutants from the surrounding environment. Ceramic jars without lids do not offer any barrier against airborne contaminants or particulates. Open glass containers expose samples directly to the air and potential contaminants, significantly increasing the likelihood of sample compromise. Therefore, brass or stainless steel tubes are the most reliable choice for preserving sample integrity and preventing contamination.